Pattern and predictive factors of occult contralateral central lymph node metastases in unilateral papillary thyroid carcinoma with ipsilateral clinical lymph node metastasis

Pattern and predictive factors of occult contralateral central lymph node metastases in unilateral papillary thyroid carcinoma with ipsilateral clinical lymph node metastasis | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Pattern and predictive factors of occult contralateral central lymph node metastases in unilateral papillary thyroid carcinoma with ipsilateral clinical lymph node metastasis Chunhao Liu, Hao Zhao, Ying Lu, Yu Xia, Ziwen Liu, Ge Chen, Yuewu Liu, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4210730/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 3 You are reading this latest preprint version Abstract Background No significant difference in disease-specific survival and recurrence-free survival exists between papillary thyroid cancer (PTC) patients with high-risk features subjected to lobectomy and thyroidectomy. However, it is unclear which type of patients with unilateral PTC combined with ipsilateral clinical involved lymph nodes (cN1) can receive a less aggressive treatment. Methods We collected the medical records of 631 patients diagnosed with unilateral PTC and ipsilateral cN1. These patients initially underwent total thyroidectomy and bilateral central lymph node dissection (LND), with or without lateral LND. We conducted an analysis to investigate the associations between contralateral occult central lymph node metastasis (CLNM) and clinicopathologic factors. Results The proportion of contralateral occult CLNM was 38.9%. age ≤ 45 years, tumor diameter > 1 cm, obesity, and involvement of lymph node regions ≥ 2 were independent risk factors for contralateral occult CLNM. Multifocality and ipsilateral neck high-volume lymph node metastases were independent risk factors among the postoperative pathological factors. A predicting model was developed to quantify the risk of each factor, which revealed that patients without any of the risk factors mentioned above had a 20–30% probability of contralateral occult CLNM, whereas the probability was greater than 60% when all factors were present. Conclusion Although the rate of contralateral occult CLNM was not low in patients with unilateral PTC combined with ipsilateral cN1, the scope of surgery could be reduced for non-obese patients with over 45 years old, tumor diameter ≤ 1 cm, and only one preoperative lymph node region involved. papillary thyroid carcinoma occult lymph node metastasis lymph node dissection pattern predictive factors Figures Figure 1 Figure 2 Introduction Papillary thyroid cancer (PTC) is the most common type of thyroid neoplasm, accounting for over 90% of cases ( 1 , 2 ). It is generally known to have an indolent disease course and good prognosis ( 3 ). However, a significant proportion of PTC patients, ranging between 30–90%, have lymph node metastasis (LNM) at the time of their initial surgery, with even higher rates in those with clinically involved LNs (cN1) ( 4 , 5 ). The current guidelines recommend total thyroidectomy for PTC patients with high-risk features, which include those with primary tumor above 4 cm, gross extrathyroidal extension, acroscopic multifocality, and confirmed nodal metastasis including pathological lateral neck metastasis (pN1b) and more than five central lymph node metastases (CLNMs) ( 6 ). These recommendations arise from the fact that these patients may benefit from postoperative radioiodine ablation and thyroglobulin follow-up, due to the relatively high possibility of recurrence ( 6 ). However, some studies revealed no significant difference in disease-specific survival and recurrence-free survival in PTC patients with high-risk features between the lobectomy and total thyroidectomy groups ( 7 , 8 ). In addition, PTC patients with high-risk features may not require 131 I treatment after an appropriate treatment ( 9 , 10 ). All this may lead to considering a less aggressive treatment for PTC patients with high-risk features. It is currently unclear which type of unilateral PTC patients with ipsilateral cN1 can receive less aggressive treatment that still ensures a good oncological outcome and reduces the risk of surgical complications. Previous studies showed that only approximately one-third of patients with unilateral PTC and ipsilateral cN1b have occult CLNM ( 5 ). Additionally, the risk of occult CLNM is lower in PTC patients with a tumor diameter less than 1 cm. Therefore, lobectomy plus ipsilateral neck lymph node dissection (LND) is a viable surgical option since most of the patients do not have occult CLNM. A complete resection of the lesion with a less aggressive surgical extent can be performed after careful evaluation, resulting in good long-term treatment outcomes and fewer complications. However, the research on the correct selection of patients who may benefit from less aggressive treatment is scarce. This study analyzed the clinical data of patients with unilateral malignant lesions and ipsilateral cN1 detected by preoperative examination to explore which of them can be subjected to a less aggressive surgical approach (such as unilateral lobectomy and ipsilateral LND), which still ensures good oncological outcomes ( 7 , 8 ), reduces complications and unnecessary treatments, and provides reference for clinical decision-making. Methods The medical records of the following consecutive PTC patients were retrospectively collected: patients who underwent total thyroidectomy plus bilateral central LND with or without ipsilateral lateral neck LND from January 2013 to December 2020. Preoperative ultrasound performed in all patients provided data on the extent of thyroid disease and suspicious cervical central and lateral lymphadenopathy. Patients with unilateral suspicious malignant lesions and ipsilateral cN1 were selected according to the preoperative evaluation and the confirmation as PTC by postoperative pathological examination. The exclusion criteria where the following: a. other pathologic types of thyroid malignancies; b. presence of suspicious contralateral central LNM by physical examination; preoperative US or CT; c. presence of malignant lesions in both thyroid lobes by preoperative imaging. This study was approved by the Ethics Committee of Peking Union Medical College Hospital and all patients provided a signed informed consent. The determination of cN1 was performed by professional thyroid ultrasound physicians. The criteria were as follows: enlargement and round shape, loss of the fatty hilum, peripheral vascularity, hyperechogenicity, cystic aspect and microcalcifications; the presence of at least 3 of the above criteria defined the cN1. The presence and number of metastatic lymph nodes were determined by postoperative pathology. High-volume LNMs were defined as more than 5 metastatic lymph nodes. Central neck LND was extended superiorly to the hyoid bone, inferiorly to the innominate vein, laterally to the carotid sheaths, and dorsally to the prevertebral fascia. After central neck LND was finished, the sample was divided into 3 portions and labeled as follows: pretracheal, ipsilateral, and contralateral paratracheal. The pretracheal and paratracheal region ipsilateral to the tumor location was defined as the ipsilateral central compartment and the paratracheal region contralateral to the tumor location was defined as the contralateral central compartment. Comprehensive LND in the lateral neck was performed using the usual fashion from level II to level V, sparing the internal jugular vein, spinal accessory nerve, and sternocleidomastoid muscle ( 11 ). LND specimens were also separated by the surgeon according to the neck levels and were then sent to the pathology department for permanent section and additional analysis. Statistical analysis was performed using SPSS 22.0 statistical software (SPSS Inc, Chicago, IL, USA). Results are expressed as mean ± standard deviation (SD). Differences between categorical variables were analyzed by the chi-squared (c2) test. The risk factors for LNM in the contralateral central neck compartment (contralateral level VI) were identified by multivariate logistic regression analysis. The odds ratios (ORs) and confidence intervals (CIs) were calculated. A value of p < 0.05 was considered statistically significant. Variables with p < 0.05 in the multivariate analysis were then used to construct the risk prediction model nomogram using the R software. The discriminative power and the consensus of our established prediction model were evaluated using the receiver operating characteristic curve The performance of the nomogram was further evaluated by the calibration chart, which plotted the predicted probability of the nomogram against the observed probability. The possibility of contralateral CLNM and ipsilateral high-volume LNMs were quantified as a risk score using the nomogram. Results 1. Clinicopathological features This study included a total of 631 patients, of which 405 were females (64.2%). The mean age was 36 years, ranging from 18 to 77 years, and 72.3% of the patients were ≤ 45 years old. The diameter of the largest tumor was 1.58±0.88 cm, and 196 patients (31.1%) had a diameter less than or equal to 1 cm. The involved lymph node regions in the neck were the following: central neck only (25.3%), lateral neck only (37.5%), and central + lateral neck (37.2%). The diameter of the largest involved lymph node detected by ultrasound was 1.48±0.88 cm, and 215 patients (34.1%) had a diameter less than or equal to 1 cm. A total of 202 (32.0%) patients were diagnosed with chronic lymphocytic thyroiditis. The postoperative pathology revealed that the proportion of patients with multiple foci was 31.7%, while the proportion of patients with contralateral occult lesions was 19.1%. The proportion of patients with capsular invasion was 69.7%. The proportions of ipsilateral LNM and high-volume LNMs were 91.2% and 57.5%, respectively. The proportions of contralateral occult CLNM and high-volume CLNMs were 38.9% and 3.9%, respectively (Table 1). 2. Correlation between preoperative involved lymph node regions and postoperative pathological LNM. The preoperative involved lymph node regions were the following: a. central neck only: the proportion of ipsilateral CLNM was 79.4% and the contralateral occult CLNM was 32.3%; b. lateral neck only: the proportion of ipsilateral CLNM was 82.5%, the ipsilateral lateral neck LNM（LLNM） was 83.9%, and the contralateral occult CLNM was 37.4%; c. both central and lateral neck: the proportion of ipsilateral CLNM was 91.4%, ipsilateral LLNM was 87.1% and contralateral occult CLNM was 50.9%. The proportion of ipsilateral CLNM（91.4% vs 79.4%, 91.4% vs 82.5%, p < 0.05）and contralateral occult CLNM（50.9% vs 32.3%, 50.9% vs . 37.4%, p < 0.05）were significantly higher in patients with preoperative involved lymph node regions in both the central and lateral neck, compared to those with lymph nodes only in the central or lateral neck regions. Among the 56 patients who did not have pathological LNM in the ipsilateral compartment, 5 (8.9%) had contralateral occult CLNM, and among them, 3 had occult PTC lesions in the contralateral lobe (Table 2). 3. Univariate and multivariate analyses of contralateral occult CLNM and ipsilateral high-volume LNMs The relationship between contralateral occult CLNM and clinicopathological factors was assessed in 631 cN1 PTC patients. The proportion of patients with contralateral occult CLNM was significantly higher in male (45.6% vs 35.3%, p = 0.011), patients with age ≤ 45 years (43.0% vs 28.6%, p = 0.001), patients with the largest tumor diameter > 1 cm (43.7% vs 28.6%, p = 0.001), patients with the largest involved lymph node diameter > 1 cm (42.3% vs 32.6%, p = 0.017), patients with absent chronic lymphocytic thyroiditis (42.7% vs 31.2%, p = 0.006), patients with a BMI ≥ 27.9 (54.4% vs 36.4%, p = 0.001), and patients with involved lymph node regions ≥ 2 (46.9% vs 32.0%, p < 0.001). Postoperative pathological factors such as multifocality (47.0% vs 35.3%, p = 0.016), contralateral occult lesion (48.8% vs 36.7%, p = 0.014), ipsilateral neck LNM (41.9% vs 8.9%, p < 0.001), and ipsilateral neck high volume LNMs (52.3% vs 20.9%, p 1 cm (OR = 1.259), BMI ≥ 27.9 (OR = 1.745), and involved lymph node regions ≥ 2 (OR = 1.573) were independent risk factors for contralateral occult CLNM, while chronic lymphocytic thyroiditis (OR = 0.608) was a protective factor. The multivariate analysis performed among the postoperative pathological factors showed that multifocality (OR = 1.568) and ipsilateral neck high-volume LNM (OR = 3.636) were independent risk factors for contralateral occult CLNM, while chronic lymphocytic thyroiditis (OR = 0.577) was also a protective factor (Table 3 and 4). Since the ipsilateral high-volume LNM was an important risk factors of contralateral occult CLNM, the risk factors for ipsilateral high-volume LNMs were further analyzed. The univariate analysis revealed that male (66.1% vs 52.7%, p = 0.011), age ≤ 45 years (61.8% vs 46.3%, p 1 cm (62.5% vs 46.4%, p 1 cm (66.3% vs 40.5%, p < 0.001), BMI ≥ 27.9 (72.5% vs 55.0%, p = 0.002), and preoperative involved lymph node regions ≥ 2 (72.8% vs 42.4%, p < 0.001), were significantly associated with an increased incidence of ipsilateral high-volume LNMs. The multivariate analysis revealed that male (OR = 1.482), age ≤ 45 years (OR = 1.994), tumor diameter > 1 cm (OR = 1.798), largest involved lymph node diameter > 1 cm (OR = 2.071), BMI ≥ 27.9 (OR = 1.828), and preoperative involved lymph node regions ≥ 2 (OR = 3.196) were independent risk factors for ipsilateral high-volume LNMs (Table 3 and 4). the relationship between ipsilateral/contralateral LNM and immediate response to therapy was also analyzed in 110 cN1 PTC patients who were subjected to surgery by the same surgeon (Dr. Li XY). The results showed no statistical difference in the immediate response to therapy between patients with or without contralateral occult CLNM, with a proportion of structural incomplete response of 8.1% and 2.7%, respectively. Patients with ipsilateral neck high-volume LNMs had a higher probability to develop a structural incomplete response (8.7% vs 0.0%, p < 0.05) or biochemical incomplete response (10.5% vs 1.9%, p < 0.05). Among the 5 patients with structural incomplete response, 4 had lung metastasis and 1 had a local LNM; all 5 patients had ipsilateral neck high-volume LNMs, and 2 of them also had contralateral occult CLNM (Table 3). 4. Nomogram for predicting contralateral occult CLNM and ipsilateral high-volume LNMs A nomogram was constructed to predict the individual risk of contralateral CLNM and ipsilateral high-volume LNMs according to the independent factors evaluated by multivariate analysis. The risk of each factor was quantified in our predicting model (the score of each factor is shown in Figure 1A and 1B) to predict the presence of contralateral CLNM and ipsilateral high-volume LNMs in unilateral PTC patients with ipsilateral cN1. The receiver operating characteristics (ROC) curve and area under the ROC curve (AUC) are shown in Figure 2A and 2B. Furthermore, a calibration plot for our nomogram was constructed, and a favorable agreement was found between the actual probability and the estimated one of the contralateral CLNM and ipsilateral high-volume LNMs (Supplementary Figure 1 and 2). Discussion Total thyroidectomy is often recommended in patients diagnosed with PTC who have a solitary lobe lesion and clinical LNM, according to numerous guidelines. This approach removes any hidden lesions on the opposite side and facilitate postoperative radioiodine ablation followed by thyroglobulin follow-up. The goal of this approach is to minimize the risk of recurrence, lower mortality rates, and ameliorate the overall prognosis ( 6 ). However, recent studies showed that PTC patients with high-risk characteristics who underwent lobectomy and total thyroidectomy do not show any statistically significant difference in 10-year disease-specific survival and disease-free survival ( 7 , 8 ). A study showed that nearly 70% of patients with unilateral PTC combined with ipsilateral cN1b do not have occult CLNM ( 5 ). However, lobectomy performed in specific patients may still result in the complete removal of the lesion, achieving results similar to total thyroidectomy. Our study explored the manner to select feasible patients for lobectomy, and the results showed that the proportion of contralateral occult CLNM was 38.9% among patients with a preoperative evaluation of unilateral malignant lesions and concurrent cN1 on the same side. The proportion of contralateral occult CLNM in patients with preoperative involved lymph node regions ≥ 2, especially those with the involvement of central and lateral neck and postoperative ipsilateral neck high-volume LNMs, reached 46.9%, 50.9%, and 52.3%, respectively. The postoperative ipsilateral neck high-volume LNMs were the most important risk factor for contralateral occult CLNM; it was also closely related to poor postoperative immediate response to therapy, and the proportion of structural incomplete response in patients with ipsilateral neck high-volume LNMs was significantly higher than that in non-high-volume LNM patients. Clinical factors related to contralateral occult CLNM in patients with unilateral PTC with ipsilateral cN1 may help the preoperative decision of performing contralateral thyroidectomy and LND ( 5 , 12 ). Previous studies showed that age ≤ 45 years, male sex, tumor diameter > 1 cm, multifocality, ipsilateral CLNM, and presence of LNM in the lateral neck region were independent risk factors for contralateral occult CLNM ( 4 , 5 , 13 , 14 ). This study also identified some risk factors reported in previous studies. However, the risk factor "preoperative involved lymph node regions ≥ 2" is not mentioned in the literature. The rate of contralateral occult CLNM in patients with cN1b in our group was similar to the proportion reported by Bon et al ( 5 ). However, the rate of contralateral occult CLNM significantly increased and was significantly higher than that in patients without these characteristics when patients had preoperative involved lymph node regions ≥ 2, especially when the central and lateral neck regions were simultaneously involved. The present study highlighted the important finding of a significantly higher rate of contralateral occult CLNM in obese patients compared to non-obese patients. Obesity is also an independent risk factor for contralateral occult CLNM. Hence, a more aggressive surgical approach should be considered for such patients, including total thyroidectomy and bilateral central LND, with a careful intraoperative lymph node clearance to reduce the probability of residual metastatic foci and minimize the risk of recurrence. Currently, the association between obesity and the aggressiveness of thyroid cancer remains controversial ( 15 , 16 , 17 , 18 ), although a greater risk of developing thyroid cancer showing more invasive pathological features exists in obese patients ( 19 , 20 , 21 , 22 ), as well as a significant correlation with tumor recurrence ( 23 ). The present study also supports the notion that obesity is associated with the invasiveness of PTC, especially an increased risk of LNM. This study found that the ipsilateral neck high-volume LNM was the most important independent risk factor for contralateral occult CLNM when the postoperative factors were included in the analysis. Patients with this condition not only had a significantly higher proportion of contralateral occult CLNM, but the postoperative immediate response to therapy was also poorer, especially in those with structural incomplete response, while contralateral occult CLNM was not related to postoperative immediate response to therapy. Thus, patients with ipsilateral neck high-volume LNMs should receive more active diagnosis and treatment. However, the presence of high-volume LNMs could only be confirmed after operation. Therefore, a model to predict the probability of its occurrence was established according to the relevant risk factors. Our results showed that the risk factors for high-volume LNMs and the predictive results of the model were similar to those for contralateral occult CLNM, with the important risk factors being age ≤ 45 years, tumor diameter > 1 cm, obesity, and preoperative involved lymph node regions ≥ 2. Although the efficiency of the predictive model was not perfect, the probability of ipsilateral high-volume LNMs and contralateral occult CLNM when all the above risk factors are present was over 75% and 60%, respectively, while the probability of ipsilateral high-volume LNMs and contralateral occult CLNM was 20–30% when none of the above risk factors was present. Therefore, our recommendation is that patients with all the above risk factors should undergo total thyroidectomy + bilateral central LND, while it is feasible to narrow the scope of the operation, such as lobectomy plus ipsilateral neck LND in those patients without the above risk factors. The limitations of this study are the following: this was a single-center, retrospective study, which might result in selection bias. Only a small number of patients in this study had an immediate evaluation of the postoperative therapeutic response, and more comprehensive data are still needed. In addition, the data of the follow-up are missing, thus, it was not possible to evaluate the differences in long-term treatment outcomes. Conclusions In conclusion, although the rate of contralateral occult CLNM was not low in patients with unilateral PTC combined with ipsilateral cN1, the risk of ipsilateral high-volume LNMs and contralateral occult CLNM was small when non-obese patients were over 45 years old, tumor diameter was less than 1 cm, and only one preoperative lymph node region was involved. Thus, the scope of surgery could be reduced for such patients. Declarations Ethics approval and consent to participate This study was approved by the Ethics Committee of Peking Union Medical College Hospital and all patients provided a signed informed consent. Conflict of Interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Consent for publication Not applicable. Availability of data and materials All data generated or analysed during this study are included in this published article. Competing interests The authors declare that they have no competing interests. Funding This work was supported by the Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences (grant numbers: 2019XK320011) and the National High Level Hospital Clinical Research Funding (grant numbers: 2022-PUMCH-B-003) Author Contributions Study conception and design: CL, XL; Acquisition of data: CL, HZ, YL, ZL, GC, YL, SL, LG; Analysis and interpretation of data: CL, YX, XL; Drafting of manuscript: CL Critical revision and final approval: XL. Acknowledgments The authors thank Mr. Yanlong Li for statistical guidance. References Sung H, Ferlay J, Siegel RL, et al. Global Cancer Statistics 2020: GLOBOCAN Estimates of Incidence and Mortality Worldwide for 36 Cancers in 185 Countries. CA Cancer J Clin. 2021;71(3):209-49. Lim H, Devesa SS, Sosa JA, et al. Trends in Thyroid Cancer Incidence and Mortality in the United States, 1974-2013. JAMA. 2017;317(13):1338-48. Lundgren CI, Hall P, Dickman PW, et al. 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Clinicopathological features Item Number（%） Sex Male 226（35.8%） Female 405（64.2%） Age, y Mean ± SD 38.5 ± 10.9 Median（Range） 36 （18-77） ≤ 45 456（72.3%） ＞45 175（27.7%） Involved lymph node regions in the neck central neck（VI） 126（20.0%） lateral neck（II/III/IV） 342（54.2%） central and lateral neck (VI+ II/III/IV) 163（25.8%） No. of involved lymph node regions in the neck one involved region 337（53.4%） ≥2 involved regions 294（46.6%） Diameter of clinical metastatic LN（cm） 1.48 ± 0.88 ≤1cm/＞1cm 215（34.1%）/ 416（65.9%） ≤2cm/＞2cm 521（82.6%）/ 110（17.4%） ≤3cm/＞3cm 605（95.9%）/ 26 （4.1%） Diameter of largest tumor（cm） 1.58 ± 0.88 ≤1cm/＞1cm 196（31.1%）/ 435（68.9%） ≤2cm/＞2cm 484（76.7%）/ 147（23.3%） Number of suspicious malignant lesions Multifocality 141（22.3%） Solitary 490（77.7%） Chronic lymphocytic thyroiditis Presence 202（32.0%） Absence 429（68.0%） Body mass index Underweight (< 18.5) 30 （4.8%） Normal weight (18.5~23.9) 312（49.4%） Overweight (24~27.9) 198（31.4%） Obese (≥ 27.9) 91 （14.4%） BRAF mutation Negative 63 （10.0%） Positive 275（43.6%） NA 292（46.4%） Operation TT + bilateral CLND 126（19.9%） TT + bilateral CLND+ ipsilateral LLND 505（80.1%） Pathological subtype Classic 522（82.7%） Follicular variant 98 （15.5%） Solid variant. 8 （1.3%） Diffuse sclerosing variant 1 （0.16%） Clear cell variant 1 （0.16%） Hobnail variant 1 （0.16%） Multifocality Presence 200（31.7%） Unilateral 79 (12.5%) Bilateral 121 (19.2%) Absence 431（68.3%） Capsule invasion Absence 191（30.3%） Presence 440（69.7%） Pathological LNM Absence 51 (8.0%) Presence 580 (92%) 1-5 metastatic LNs 191 (33.7%) ＞5 metastatic LNs 389 (57.5%) Ipsilateral neck Absence 56 (8.8%) Presence 575 (91.2%) 1-5 metastatic LNs 212 (33.7%) ＞5 metastatic LNs 363 (57.5%) Contralateral neck Absence 385 (61.1%) Presence 246 (38.9%) 1-5 metastatic LNs 221 (35.0%) ＞5 metastatic LNs 25 (3.9%) TT total thyroidectomy; CLND, central lymph node dissection; LLND, lateral lymph node dissection; NA, not available; LNs, lymph nodes. Table 2. Relationship between Involved lymph node regions and postoperative pathological lymph node metastasis. Item Involved lymph node regions in the neck P -value Central (N=126) Lateral (N=342) Central + Lateral (N=163) Postoperative pathological lymph node metastasis Ipsilateral central neck Number of dissected lymph nodes 10.98±5.43 9.19±5.76 10.77±5.93 Absence 26 （20.6%） 60 （17.5%） 14 （8.6%） 0.009 Presence 100（79.4%） 282（82.5%） 149（91.4%） 1-5 metastatic LNs 68 （54.0%） 187（54.7%） 69 （42.3%） <0.001 ＞5 metastatic LNs 32 （25.4%） 95 （27.8%） 80 （49.1%） Number of metastatic LNs of patients with pN (+) 4.76±3.25 4.81±3.75 6.68±4.28 Ipsilateral lateral neck Number of dissected lymph nodes - 22.85 ± 11.61 24.29 ± 12.47 Absence - 55 （16.1%） 21 （12.9%） 0.347 Presence - 287（83.9%） 142（87.1%） 1-5 metastatic LNs - 192（56.1%） 90 （55.2%） 0.340 ＞5 metastatic LNs - 95 （27.8%） 52 （31.9%） Number of metastatic LNs of patients with pN (+) - 4.82±3.66 5.55±4.38 0.070 Contralateral central neck Number of dissected lymph nodes 5.61±3.56 4.35 ± 3.71 4.56 ± 3.70 Absence 91 （72.2%） 214（62.6%） 80 （49.1%） <0.001 Presence 35 （27.8%） 128（37.4%） 83 （50.9%） 1-5 metastatic LNs 33 （30.5%） 111（32.5%） 157（47.2%） 0.245 ＞5 metastatic LNs 2 （1.5%） 17 （4.9%） 6 （3.7%） Number of metastatic LNs of patients with pN (+) 2.34±1.66 2.80 ± 2.75 2.48 1.83 pN+, pathological lymph node positive; LNs, lymph nodes. Table 3. Univariate Logistic Regression for Contralateral Central LNM and Ipsilateral high-volume LNMs Item Contralateral CLNM, no. (%) P-value Ipsilateral high-volume LNMs, no. (%) P -value Absence（N=385） Presence （N=246） Absence（N=268） Presence（N=363） Sex Male 123（54.4%） 103（45.6%） 0.011 77（33.9%） 150（66.1%） 0.001 Female 262（64.7%） 143（35.3%） 191（47.3%） 213（52.7%） Age, y ≤ 45 260（57.0%） 196（43.0%） 0.001 174（38.2%） 282（61.8%） <0.001 ＞45 125（71.4%） 50 （28.6%） 94（53.7%） 81 （46.3%） Diameter of largest tumor（cm） ≤ 1 140（71.4%） 56 （28.6%） <0.001 105（53.6%） 91 （46.4%） <0.001 ＞1 245（56.3%） 190（43.7%） 163（37.5%） 272（62.5%） ≤2 316（65.3%） 168（34.7%） <0.001 230（47.5%） 254（52.5%） <0.001 ＞2 69 （46.9%） 78 （53.1%） 38 （25.9%） 109（74.1%） Number of suspicious malignant lesions Multifocality 78 （55.3%） 63 （44.7%） 0.116 51 （44.3%） 90 （55.7%） 0.086 Solitary 307（62.7%） 183（37.3%） 217（36.2%） 273（63..8%） Diameter of clinical metastatic LN（cm） ≤1 145（67.4%） 70 （32.6%） 0.017 128（59.5%） 87 （40.5%） <0.001 ＞1 240（57.7%） 176（42.3%） 140（33.7%） 276（66.3%） Involved lymph node regions in the neck Central 91 （72.2%） 35 （27.8%） <0.001 94（74.6%） 32 （25.4%） <0.001 Lateral 214（62.6%） 128（37.4%） 139（40.6%） 203（59.4%） Central + Lateral 80 （49.1%） 83 （50.9%） 35 （21.5%） 128 （78.5%） No. of involved lymph node regions in the neck one involved region 229（68.0%） 108（32.0%） <0.001 194（57.6%） 143（42.4%） <0.001 ≥ 2 involved regions 156（53.1%） 138（46.9%） 74（25.2%） 220（74.8%） Chronic lymphocytic thyroiditis Presence 139（68.8） 63 （31.2%） 0.006 183（42.7%） 246 （57.3%） 0.891 Absence 246（57.3） 183（42.7%） 85 （42.1%） 117 （57.9%） BRAF mutation Negative 42 （66.7%） 21 （33.3%） 0.080 19 （30.2%） 44 （69.8%） 0.162 Positive 150（54.5%） 125（45.5%） 109（39.6%） 166（60.4%） Body mass index Underweight / Normal weight / Overweight 343（63.5%） 197（36.5%） 0.002 243（45.0%） 297（55.0%） 0.002 Obese 42（46.2%） 49（53.8%） 25（27.5%） 66（72.5%） Multifocality Presence 106（53.0%） 94 （47.0%） 0.016 79 （39.5%） 121 （60.5%） 0.304 Unilateral 44 （55.7%） 35 （44.3%） 24 （30.4%） 55 （69.6%） Bilateral 62 （51.2%） 59 （48.8%） 55 （45.5%） 66 （54.5%） Absence 279（64.7%） 152（35.3%） 189（64.7%） 242（35.3%） Capsule invasion Absence 120（62.8%） 71 （37.2%） 0.538 93（48.7%） 98 （51.3%） 0.037 Presence 265（60.2%） 175（39.8%） 175（39.8%） 265（60.2%） Ipsilateral pathological LNM Absence 51 （91.1%） 5 （8.9%） <0.001 - - - Presence 334（58.1%） 241（41.9%） - - Ipsilateral pathological high-volume LNMs Absence 212（79.1%） 56 （20.9%） <0.001 - - - Presence 173（47.7%） 190（52.3%） - - Response to therapy（n=110） Excellent response 33（78.6%） 9（21.4%） 0.091 27（64.3%） 15（35.7%） 0.006 Indeterminate response 35（62.5%） 21（37.5%） 25（44.6%） 31（55.4%） Biochemical Incomplete response 3（42.9%） 4（57.1%） 1（14.3%） 6（85.7%） Structural Incomplete response 2（40.0%） 3（60.0%） 0（0.0%） 5（100.0%） LN, lymph node; LNM, lymph node metastasis, LNMs, lymph node metastases Table 4. Multivariate Logistic Regression for Contralateral Central LNM and Ipsilateral high-volume LNMs Item Sig Exp(B) 95% CI Contralateral CLNM Preoperative factors Male 0.292 1.217 0.845-1.754 Age ≤ 45 years old 0.001 1.978 1.339-2.924 Tumor diameter ＞ 1cm 0.001 1.913 1.311-2.791 Diameter of involved lymph node >1cm 0.230 1.259 0.864-1.835 Chronic lymphocytic thyroiditis 0.009 0.608 0.417-0.885 Obese 0.024 1.745 1.075-2.833 No. of involved lymph node regions in the neck > 2 0.012 1.573 1.105-2.239 Postoperative factors Male 0.514 1.135 0.776-1.662 Age ≤ 45 years old 0.010 1.711 1.138-2.571 Tumor diameter ＞ 1cm 0.004 1.780 1.203-2.635 Chronic lymphocytic thyroiditis 0.006 0.577 0.392-0.851 Obese 0.106 1.514 0.915-2.504 Multifocality 0.018 1.568 1.082-2.272 Ipsilateral pathological high-volume LNMs <0.001 3.636 2.501-5.284 Ipsilateral high-volume LNMs Preoperative factors Male 0.042 1.482 1.014-2.164 Age ≤ 45 years old 1cm <0.001 2.071 1.426-3.007 Obese 0.032 1.828 1.052-3.177 No. of involved lymph node regions in the neck ≥2 <0.001 3.196 2.218-4.605 CLNM, central lymph node metastasis; LNM, lymph node metastasis; LNMs, lymph node metastases Additional Declarations No competing interests reported. Supplementary Files Supplementaryfigure1.tif Supplementary Figure 1. Calibration plot for our nomogram for contralateral central neck LNM and ipsilateral high-volume LNM.CCLNM, contralateral central neck lymph node metastasis; ip-hvLNMs, ipsilateral high volume lymph node metastases. Cite Share Download PDF Status: Under Review Version 1 posted Editor assigned by journal 06 Apr, 2024 Submission checks completed at journal 04 Apr, 2024 First submitted to journal 03 Apr, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4210730","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":288228554,"identity":"fafe35a9-a2a3-4c6c-8aa2-27e971d84ff0","order_by":0,"name":"Chunhao Liu","email":"","orcid":"","institution":"Chinese Academy of Medical Sciences \u0026 Peking Union Medical College","correspondingAuthor":false,"prefix":"","firstName":"Chunhao","middleName":"","lastName":"Liu","suffix":""},{"id":288228555,"identity":"d9c38d41-76ab-43c5-a3e8-b26bb62707b7","order_by":1,"name":"Hao Zhao","email":"","orcid":"","institution":"Chinese Academy of Medical Sciences \u0026 Peking Union Medical College","correspondingAuthor":false,"prefix":"","firstName":"Hao","middleName":"","lastName":"Zhao","suffix":""},{"id":288228556,"identity":"f32c9f68-ec5c-4108-84af-26808172179f","order_by":2,"name":"Ying Lu","email":"","orcid":"","institution":"Chinese Academy of Medical Sciences \u0026 Peking Union Medical College","correspondingAuthor":false,"prefix":"","firstName":"Ying","middleName":"","lastName":"Lu","suffix":""},{"id":288228557,"identity":"2b9d2318-8cef-4185-95f8-2a9afcdeb0f4","order_by":3,"name":"Yu Xia","email":"","orcid":"","institution":"Chinese Academy of Medical Sciences \u0026 Peking Union Medical College","correspondingAuthor":false,"prefix":"","firstName":"Yu","middleName":"","lastName":"Xia","suffix":""},{"id":288228558,"identity":"cb32299b-b65f-474b-80c5-831b79e0ce1a","order_by":4,"name":"Ziwen Liu","email":"","orcid":"","institution":"Chinese Academy of Medical Sciences \u0026 Peking Union Medical College","correspondingAuthor":false,"prefix":"","firstName":"Ziwen","middleName":"","lastName":"Liu","suffix":""},{"id":288228559,"identity":"e40f7df7-8f5a-4ee9-b28b-978f4fa4940f","order_by":5,"name":"Ge Chen","email":"","orcid":"","institution":"Chinese Academy of Medical Sciences \u0026 Peking Union Medical College","correspondingAuthor":false,"prefix":"","firstName":"Ge","middleName":"","lastName":"Chen","suffix":""},{"id":288228560,"identity":"8f398ca5-dd35-4430-8f28-024a242883a2","order_by":6,"name":"Yuewu Liu","email":"","orcid":"","institution":"Chinese Academy of Medical Sciences \u0026 Peking Union Medical College","correspondingAuthor":false,"prefix":"","firstName":"Yuewu","middleName":"","lastName":"Liu","suffix":""},{"id":288228561,"identity":"a0cc6706-ab8d-440b-a6a7-32ddcb667ce4","order_by":7,"name":"Shuzhou Liu","email":"","orcid":"","institution":"Hainan General Hospital","correspondingAuthor":false,"prefix":"","firstName":"Shuzhou","middleName":"","lastName":"Liu","suffix":""},{"id":288228562,"identity":"1d5fb16a-c31c-4f15-bf51-5df3e93c4fa6","order_by":8,"name":"Luying Gao","email":"","orcid":"","institution":"Chinese Academy of Medical Sciences \u0026 Peking Union Medical College","correspondingAuthor":false,"prefix":"","firstName":"Luying","middleName":"","lastName":"Gao","suffix":""},{"id":288228563,"identity":"5631b42c-d083-40f2-8d27-685b6ca1dbe0","order_by":9,"name":"Xiaoyi Li","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA0UlEQVRIiWNgGAWjYBACPmYgkQDEbOzNBx9+IEYLG1wLz7FkYwkgg4egFjhLIsdMgIcoLewMbBIPamwS+yQfmDFIMNyRsyfCYcwGCcfSEtukE9IeFDA8MyZsCzMD44MEtsMgLccNJBgOJ/YQoYXhQMI/oBbJg20SPAyH64nRwvggsQ2oRYKZDaQlgQiHMTYbJPalGbfxpDEbSxgcNuw5QEALP//hY5I/vtnIzm8///Hhh4rD8uwNhKxhYAQrcYQoNCCoHAEIxsYoGAWjYBSMYAAAG8E2PxzmeXEAAAAASUVORK5CYII=","orcid":"","institution":"Chinese Academy of Medical Sciences \u0026 Peking Union Medical College","correspondingAuthor":true,"prefix":"","firstName":"Xiaoyi","middleName":"","lastName":"Li","suffix":""}],"badges":[],"createdAt":"2024-04-03 07:28:42","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4210730/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4210730/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":54519322,"identity":"543568c7-15bc-4dfd-ac55-b71338dad23b","added_by":"auto","created_at":"2024-04-11 17:44:49","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":485145,"visible":true,"origin":"","legend":"\u003cp\u003eClinicopathological characteristics-based nomogram used for prediction of Contralateral CLNM (1A) and ipsilateral high-volume LNMs (1B). T-Diameter, tumor diameter; L-Diameter, lymph node diameter; CLNM, central lymph node metastasis; high-volume LNMs, high volume lymph node metastases; Age (years); Obese (BMI ≥ 27.9); Regions (No. of involved lymph node regions in the neck)\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-4210730/v1/aa12a627f6995b9cc2f88fb9.png"},{"id":54519169,"identity":"9cf7d947-f400-4f2d-8621-f510b485e34f","added_by":"auto","created_at":"2024-04-11 17:36:49","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":376046,"visible":true,"origin":"","legend":"\u003cp\u003eThe receiver operating characteristics (ROC) curve and area under the ROC curve (AUC) for contralateral central neck LNM and ipsilateral high-volume LNM.\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-4210730/v1/aa5204249774e93c262eaf64.png"},{"id":54519957,"identity":"0e377c56-9e98-4160-b50c-0156e283bd84","added_by":"auto","created_at":"2024-04-11 17:52:49","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":525802,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4210730/v1/d92b71fb-f2cf-4fed-a099-9e555d254c95.pdf"},{"id":54519167,"identity":"d9d69faa-27d0-4f45-bf4f-e4645ebbe1e0","added_by":"auto","created_at":"2024-04-11 17:36:49","extension":"tif","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":489356,"visible":true,"origin":"","legend":"\u003cp\u003eSupplementary Figure 1. Calibration plot for our nomogram for contralateral central neck LNM and ipsilateral high-volume LNM.CCLNM, contralateral central neck lymph node metastasis; ip-hvLNMs, ipsilateral high volume lymph node metastases.\u003c/p\u003e","description":"","filename":"Supplementaryfigure1.tif","url":"https://assets-eu.researchsquare.com/files/rs-4210730/v1/a4624cfa17029ef8c01cf1d9.tif"}],"financialInterests":"No competing interests reported.","formattedTitle":"Pattern and predictive factors of occult contralateral central lymph node metastases in unilateral papillary thyroid carcinoma with ipsilateral clinical lymph node metastasis","fulltext":[{"header":"Introduction","content":"\u003cp\u003ePapillary thyroid cancer (PTC) is the most common type of thyroid neoplasm, accounting for over 90% of cases (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). It is generally known to have an indolent disease course and good prognosis (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). However, a significant proportion of PTC patients, ranging between 30\u0026ndash;90%, have lymph node metastasis (LNM) at the time of their initial surgery, with even higher rates in those with clinically involved LNs (cN1) (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). The current guidelines recommend total thyroidectomy for PTC patients with high-risk features, which include those with primary tumor above 4 cm, gross extrathyroidal extension, acroscopic multifocality, and confirmed nodal metastasis including pathological lateral neck metastasis (pN1b) and more than five central lymph node metastases (CLNMs) (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). These recommendations arise from the fact that these patients may benefit from postoperative radioiodine ablation and thyroglobulin follow-up, due to the relatively high possibility of recurrence (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). However, some studies revealed no significant difference in disease-specific survival and recurrence-free survival in PTC patients with high-risk features between the lobectomy and total thyroidectomy groups (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). In addition, PTC patients with high-risk features may not require \u003csup\u003e131\u003c/sup\u003eI treatment after an appropriate treatment (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e). All this may lead to considering a less aggressive treatment for PTC patients with high-risk features.\u003c/p\u003e \u003cp\u003eIt is currently unclear which type of unilateral PTC patients with ipsilateral cN1 can receive less aggressive treatment that still ensures a good oncological outcome and reduces the risk of surgical complications. Previous studies showed that only approximately one-third of patients with unilateral PTC and ipsilateral cN1b have occult CLNM (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). Additionally, the risk of occult CLNM is lower in PTC patients with a tumor diameter less than 1 cm. Therefore, lobectomy plus ipsilateral neck lymph node dissection (LND) is a viable surgical option since most of the patients do not have occult CLNM. A complete resection of the lesion with a less aggressive surgical extent can be performed after careful evaluation, resulting in good long-term treatment outcomes and fewer complications. However, the research on the correct selection of patients who may benefit from less aggressive treatment is scarce. This study analyzed the clinical data of patients with unilateral malignant lesions and ipsilateral cN1 detected by preoperative examination to explore which of them can be subjected to a less aggressive surgical approach (such as unilateral lobectomy and ipsilateral LND), which still ensures good oncological outcomes (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e), reduces complications and unnecessary treatments, and provides reference for clinical decision-making.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eThe medical records of the following consecutive PTC patients were retrospectively collected: patients who underwent total thyroidectomy plus bilateral central LND with or without ipsilateral lateral neck LND from January 2013 to December 2020. Preoperative ultrasound performed in all patients provided data on the extent of thyroid disease and suspicious cervical central and lateral lymphadenopathy. Patients with unilateral suspicious malignant lesions and ipsilateral cN1 were selected according to the preoperative evaluation and the confirmation as PTC by postoperative pathological examination. The exclusion criteria where the following: a. other pathologic types of thyroid malignancies; b. presence of suspicious contralateral central LNM by physical examination; preoperative US or CT; c. presence of malignant lesions in both thyroid lobes by preoperative imaging. This study was approved by the Ethics Committee of Peking Union Medical College Hospital and all patients provided a signed informed consent.\u003c/p\u003e \u003cp\u003eThe determination of cN1 was performed by professional thyroid ultrasound physicians. The criteria were as follows: enlargement and round shape, loss of the fatty hilum, peripheral vascularity, hyperechogenicity, cystic aspect and microcalcifications; the presence of at least 3 of the above criteria defined the cN1. The presence and number of metastatic lymph nodes were determined by postoperative pathology. High-volume LNMs were defined as more than 5 metastatic lymph nodes. Central neck LND was extended superiorly to the hyoid bone, inferiorly to the innominate vein, laterally to the carotid sheaths, and dorsally to the prevertebral fascia. After central neck LND was finished, the sample was divided into 3 portions and labeled as follows: pretracheal, ipsilateral, and contralateral paratracheal. The pretracheal and paratracheal region ipsilateral to the tumor location was defined as the ipsilateral central compartment and the paratracheal region contralateral to the tumor location was defined as the contralateral central compartment. Comprehensive LND in the lateral neck was performed using the usual fashion from level II to level V, sparing the internal jugular vein, spinal accessory nerve, and sternocleidomastoid muscle (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e). LND specimens were also separated by the surgeon according to the neck levels and were then sent to the pathology department for permanent section and additional analysis.\u003c/p\u003e \u003cp\u003eStatistical analysis was performed using SPSS 22.0 statistical software (SPSS Inc, Chicago, IL, USA). Results are expressed as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation (SD). Differences between categorical variables were analyzed by the chi-squared (c2) test. The risk factors for LNM in the contralateral central neck compartment (contralateral level VI) were identified by multivariate logistic regression analysis. The odds ratios (ORs) and confidence intervals (CIs) were calculated. A value of \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant. Variables with \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05 in the multivariate analysis were then used to construct the risk prediction model nomogram using the R software. The discriminative power and the consensus of our established prediction model were evaluated using the receiver operating characteristic curve The performance of the nomogram was further evaluated by the calibration chart, which plotted the predicted probability of the nomogram against the observed probability. The possibility of contralateral CLNM and ipsilateral high-volume LNMs were quantified as a risk score using the nomogram.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003e1. Clinicopathological features\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study included a total of 631 patients, of which 405 were females (64.2%). The mean age was 36 years, ranging from 18 to 77 years, and 72.3% of the patients were \u0026le; 45 years old. The diameter of the largest tumor was 1.58\u0026plusmn;0.88 cm, and 196 patients (31.1%) had a diameter less than or equal to 1 cm. The involved lymph node regions in the neck were the following: central neck only (25.3%), lateral neck only (37.5%), and central + lateral neck (37.2%). The diameter of the largest involved lymph node detected by ultrasound was 1.48\u0026plusmn;0.88 cm, and 215 patients (34.1%) had a diameter less than or equal to 1 cm. A total of 202 (32.0%) patients were diagnosed with chronic lymphocytic thyroiditis. The postoperative pathology revealed that the proportion of patients with multiple foci was 31.7%, while the proportion of patients with contralateral occult lesions was 19.1%. The proportion of patients with capsular invasion was 69.7%. The proportions of ipsilateral LNM and high-volume LNMs were 91.2% and 57.5%, respectively. The proportions of contralateral occult CLNM and high-volume CLNMs were 38.9% and 3.9%, respectively (Table 1).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2. Correlation between preoperative involved lymph node regions and postoperative pathological LNM.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe preoperative involved lymph node regions were the following: a. central neck only: the proportion of ipsilateral CLNM was 79.4% and the contralateral occult CLNM was 32.3%; b. lateral neck only: the proportion of ipsilateral CLNM was 82.5%, the ipsilateral lateral neck LNM（LLNM）\u0026nbsp;was 83.9%, and the contralateral occult CLNM was 37.4%; c. both central and lateral neck: the proportion of ipsilateral CLNM was 91.4%, ipsilateral LLNM was 87.1% and contralateral occult CLNM was 50.9%. The proportion of ipsilateral CLNM（91.4% \u003cem\u003evs\u003c/em\u003e 79.4%,\u0026nbsp;91.4% \u003cem\u003evs\u003c/em\u003e 82.5%,\u0026nbsp;\u003cem\u003ep\u003c/em\u003e \u0026lt; 0.05）and contralateral occult CLNM（50.9% \u003cem\u003evs\u003c/em\u003e 32.3%,\u0026nbsp;50.9% \u003cem\u003evs\u003c/em\u003e. 37.4%,\u0026nbsp;\u003cem\u003ep\u003c/em\u003e \u0026lt; 0.05）were significantly higher in patients with preoperative involved lymph node regions in both the central and lateral neck, compared to those with lymph nodes only in the central or lateral neck regions. Among the 56 patients who did not have pathological LNM in the ipsilateral compartment, 5 (8.9%) had contralateral occult CLNM, and among them, 3 had occult PTC lesions in the contralateral lobe (Table 2).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3. Univariate and multivariate analyses of contralateral occult CLNM and ipsilateral high-volume LNMs\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe relationship between contralateral occult CLNM and clinicopathological factors was assessed in 631 cN1 PTC patients. The proportion of patients with contralateral occult CLNM was significantly higher in male (45.6% \u003cem\u003evs\u003c/em\u003e 35.3%, \u003cem\u003ep\u003c/em\u003e = 0.011), patients with age \u0026le; 45 years (43.0% \u003cem\u003evs\u003c/em\u003e 28.6%, \u003cem\u003ep\u003c/em\u003e = 0.001), patients with the largest tumor diameter \u0026gt; 1 cm (43.7% \u003cem\u003evs\u003c/em\u003e 28.6%, \u003cem\u003ep\u003c/em\u003e = 0.001), patients with the largest involved lymph node diameter \u0026gt; 1 cm (42.3% \u003cem\u003evs\u003c/em\u003e 32.6%, \u003cem\u003ep\u003c/em\u003e = 0.017), patients with absent chronic lymphocytic thyroiditis (42.7% \u003cem\u003evs\u003c/em\u003e 31.2%, \u003cem\u003ep\u003c/em\u003e = 0.006), patients with a BMI \u0026ge; 27.9 (54.4% \u003cem\u003evs\u003c/em\u003e 36.4%, \u003cem\u003ep\u003c/em\u003e = 0.001), and patients with involved lymph node regions \u0026ge; 2 (46.9% \u003cem\u003evs\u003c/em\u003e 32.0%, \u003cem\u003ep\u003c/em\u003e \u0026lt; 0.001). Postoperative pathological factors such as multifocality (47.0% \u003cem\u003evs\u003c/em\u003e 35.3%, \u003cem\u003ep\u003c/em\u003e = 0.016), contralateral occult lesion (48.8% \u003cem\u003evs\u003c/em\u003e 36.7%, \u003cem\u003ep\u003c/em\u003e = 0.014), ipsilateral neck LNM (41.9% \u003cem\u003evs\u003c/em\u003e 8.9%, \u003cem\u003ep\u003c/em\u003e \u0026lt; 0.001), and ipsilateral neck high volume LNMs (52.3% \u003cem\u003evs\u003c/em\u003e 20.9%, \u003cem\u003ep\u003c/em\u003e \u0026lt; 0.001) were also significantly associated with contralateral occult CLNM. The multivariate analysis revealed that age \u0026le; 45 years (OR = 1.978), largest tumor diameter \u0026gt; 1 cm (OR = 1.259), BMI \u0026ge; 27.9 (OR = 1.745), and involved lymph node regions \u0026ge; 2 (OR = 1.573) were independent risk factors for contralateral occult CLNM, while chronic lymphocytic thyroiditis (OR = 0.608) was a protective factor. The multivariate analysis performed among the postoperative pathological factors showed that multifocality (OR = 1.568) and ipsilateral neck high-volume LNM (OR = 3.636) were independent risk factors for contralateral occult CLNM, while chronic lymphocytic thyroiditis (OR = 0.577) was also a protective factor (Table 3 and 4).\u003c/p\u003e\n\u003cp\u003eSince the ipsilateral high-volume LNM was an important risk factors of contralateral occult CLNM, the risk factors for ipsilateral high-volume LNMs were further analyzed. The univariate analysis revealed that male (66.1% \u003cem\u003evs\u003c/em\u003e 52.7%, \u003cem\u003ep\u003c/em\u003e = 0.011), age \u0026le; 45 years (61.8% \u003cem\u003evs\u003c/em\u003e 46.3%, \u003cem\u003ep\u003c/em\u003e \u0026lt; 0.001), tumor diameter \u0026gt; 1 cm (62.5% \u003cem\u003evs\u003c/em\u003e 46.4%, \u003cem\u003ep\u003c/em\u003e \u0026lt; 0.001), largest involved lymph node diameter \u0026gt; 1 cm (66.3% \u003cem\u003evs\u003c/em\u003e 40.5%, \u003cem\u003ep\u003c/em\u003e \u0026lt; 0.001), BMI \u0026ge; 27.9 (72.5% \u003cem\u003evs\u003c/em\u003e 55.0%, \u003cem\u003ep\u003c/em\u003e = 0.002), and preoperative involved lymph node regions \u0026ge; 2 (72.8% \u003cem\u003evs\u003c/em\u003e 42.4%, \u003cem\u003ep\u003c/em\u003e \u0026lt; 0.001), were significantly associated with an increased incidence of ipsilateral high-volume LNMs. The multivariate analysis revealed that male (OR = 1.482), age \u0026le; 45 years (OR = 1.994), tumor diameter \u0026gt; 1 cm (OR = 1.798), largest involved lymph node diameter \u0026gt; 1 cm (OR = 2.071), BMI \u0026ge; 27.9 (OR = 1.828), and preoperative involved lymph node regions \u0026ge; 2 (OR = 3.196) were independent risk factors for ipsilateral high-volume LNMs (Table 3 and 4).\u003c/p\u003e\n\u003cp\u003ethe relationship between ipsilateral/contralateral LNM and immediate response to therapy was also analyzed in 110 cN1 PTC patients who were subjected to surgery by the same surgeon (Dr. Li XY). The results showed no statistical difference in the immediate response to therapy between patients with or without contralateral occult CLNM, with a proportion of structural incomplete response of 8.1% and 2.7%, respectively. Patients with ipsilateral neck high-volume LNMs had a higher probability to develop a structural incomplete response (8.7% \u003cem\u003evs\u003c/em\u003e 0.0%, \u003cem\u003ep\u003c/em\u003e \u0026lt; 0.05) or biochemical incomplete response (10.5% \u003cem\u003evs\u003c/em\u003e 1.9%, \u003cem\u003ep\u003c/em\u003e \u0026lt; 0.05). Among the 5 patients with structural incomplete response, 4 had lung metastasis and 1 had a local LNM; all 5 patients had ipsilateral neck high-volume LNMs, and 2 of them also had contralateral occult CLNM (Table 3).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e4. Nomogram for predicting\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003econtralateral occult CLNM and ipsilateral high-volume LNMs\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA nomogram was constructed to predict the individual risk of contralateral CLNM and ipsilateral high-volume LNMs according to the independent factors evaluated by multivariate analysis. The risk of each factor was quantified in our predicting model (the score of each factor is shown in Figure 1A and 1B) to predict the presence of contralateral CLNM and ipsilateral high-volume LNMs in unilateral PTC patients with ipsilateral cN1. The receiver operating characteristics (ROC) curve and area under the ROC curve (AUC) are shown in Figure 2A and 2B. Furthermore, a calibration plot for our nomogram was constructed, and a favorable agreement was found between the actual probability and the estimated one of the contralateral CLNM and ipsilateral high-volume LNMs (Supplementary Figure 1 and 2).\u0026nbsp;\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003e Total thyroidectomy is often recommended in patients diagnosed with PTC who have a solitary lobe lesion and clinical LNM, according to numerous guidelines. This approach removes any hidden lesions on the opposite side and facilitate postoperative radioiodine ablation followed by thyroglobulin follow-up. The goal of this approach is to minimize the risk of recurrence, lower mortality rates, and ameliorate the overall prognosis (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). However, recent studies showed that PTC patients with high-risk characteristics who underwent lobectomy and total thyroidectomy do not show any statistically significant difference in 10-year disease-specific survival and disease-free survival (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). A study showed that nearly 70% of patients with unilateral PTC combined with ipsilateral cN1b do not have occult CLNM (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). However, lobectomy performed in specific patients may still result in the complete removal of the lesion, achieving results similar to total thyroidectomy. Our study explored the manner to select feasible patients for lobectomy, and the results showed that the proportion of contralateral occult CLNM was 38.9% among patients with a preoperative evaluation of unilateral malignant lesions and concurrent cN1 on the same side. The proportion of contralateral occult CLNM in patients with preoperative involved lymph node regions\u0026thinsp;\u0026ge;\u0026thinsp;2, especially those with the involvement of central and lateral neck and postoperative ipsilateral neck high-volume LNMs, reached 46.9%, 50.9%, and 52.3%, respectively. The postoperative ipsilateral neck high-volume LNMs were the most important risk factor for contralateral occult CLNM; it was also closely related to poor postoperative immediate response to therapy, and the proportion of structural incomplete response in patients with ipsilateral neck high-volume LNMs was significantly higher than that in non-high-volume LNM patients.\u003c/p\u003e \u003cp\u003eClinical factors related to contralateral occult CLNM in patients with unilateral PTC with ipsilateral cN1 may help the preoperative decision of performing contralateral thyroidectomy and LND (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e). Previous studies showed that age\u0026thinsp;\u0026le;\u0026thinsp;45 years, male sex, tumor diameter\u0026thinsp;\u0026gt;\u0026thinsp;1 cm, multifocality, ipsilateral CLNM, and presence of LNM in the lateral neck region were independent risk factors for contralateral occult CLNM (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e). This study also identified some risk factors reported in previous studies. However, the risk factor \"preoperative involved lymph node regions\u0026thinsp;\u0026ge;\u0026thinsp;2\" is not mentioned in the literature. The rate of contralateral occult CLNM in patients with cN1b in our group was similar to the proportion reported by Bon et al (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). However, the rate of contralateral occult CLNM significantly increased and was significantly higher than that in patients without these characteristics when patients had preoperative involved lymph node regions\u0026thinsp;\u0026ge;\u0026thinsp;2, especially when the central and lateral neck regions were simultaneously involved.\u003c/p\u003e \u003cp\u003eThe present study highlighted the important finding of a significantly higher rate of contralateral occult CLNM in obese patients compared to non-obese patients. Obesity is also an independent risk factor for contralateral occult CLNM. Hence, a more aggressive surgical approach should be considered for such patients, including total thyroidectomy and bilateral central LND, with a careful intraoperative lymph node clearance to reduce the probability of residual metastatic foci and minimize the risk of recurrence. Currently, the association between obesity and the aggressiveness of thyroid cancer remains controversial (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e), although a greater risk of developing thyroid cancer showing more invasive pathological features exists in obese patients (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e), as well as a significant correlation with tumor recurrence (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e). The present study also supports the notion that obesity is associated with the invasiveness of PTC, especially an increased risk of LNM.\u003c/p\u003e \u003cp\u003eThis study found that the ipsilateral neck high-volume LNM was the most important independent risk factor for contralateral occult CLNM when the postoperative factors were included in the analysis. Patients with this condition not only had a significantly higher proportion of contralateral occult CLNM, but the postoperative immediate response to therapy was also poorer, especially in those with structural incomplete response, while contralateral occult CLNM was not related to postoperative immediate response to therapy. Thus, patients with ipsilateral neck high-volume LNMs should receive more active diagnosis and treatment. However, the presence of high-volume LNMs could only be confirmed after operation. Therefore, a model to predict the probability of its occurrence was established according to the relevant risk factors. Our results showed that the risk factors for high-volume LNMs and the predictive results of the model were similar to those for contralateral occult CLNM, with the important risk factors being age\u0026thinsp;\u0026le;\u0026thinsp;45 years, tumor diameter\u0026thinsp;\u0026gt;\u0026thinsp;1 cm, obesity, and preoperative involved lymph node regions\u0026thinsp;\u0026ge;\u0026thinsp;2. Although the efficiency of the predictive model was not perfect, the probability of ipsilateral high-volume LNMs and contralateral occult CLNM when all the above risk factors are present was over 75% and 60%, respectively, while the probability of ipsilateral high-volume LNMs and contralateral occult CLNM was 20\u0026ndash;30% when none of the above risk factors was present. Therefore, our recommendation is that patients with all the above risk factors should undergo total thyroidectomy\u0026thinsp;+\u0026thinsp;bilateral central LND, while it is feasible to narrow the scope of the operation, such as lobectomy plus ipsilateral neck LND in those patients without the above risk factors.\u003c/p\u003e \u003cp\u003eThe limitations of this study are the following: this was a single-center, retrospective study, which might result in selection bias. Only a small number of patients in this study had an immediate evaluation of the postoperative therapeutic response, and more comprehensive data are still needed. In addition, the data of the follow-up are missing, thus, it was not possible to evaluate the differences in long-term treatment outcomes.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eIn conclusion, although the rate of contralateral occult CLNM was not low in patients with unilateral PTC combined with ipsilateral cN1, the risk of ipsilateral high-volume LNMs and contralateral occult CLNM was small when non-obese patients were over 45 years old, tumor diameter was less than 1 cm, and only one preoperative lymph node region was involved. Thus, the scope of surgery could be reduced for such patients.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was approved by the Ethics Committee of Peking Union Medical College Hospital and all patients provided a signed informed consent.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of Interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll data generated or analysed during this study are included in this published article.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported by the Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences (grant numbers: 2019XK320011) and the National High Level Hospital Clinical Research Funding (grant numbers: 2022-PUMCH-B-003)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contributions\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eStudy conception and design: CL, XL; Acquisition of data: CL, HZ, YL, ZL, GC, YL, SL, LG; Analysis and interpretation of data: CL, YX, XL; Drafting of manuscript: CL Critical revision and final approval: XL.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors thank Mr. Yanlong Li for statistical guidance.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eSung H, Ferlay J, Siegel RL, et al. Global Cancer Statistics 2020: GLOBOCAN Estimates of Incidence and Mortality Worldwide for 36 Cancers in 185 Countries. CA Cancer J Clin. 2021;71(3):209-49.\u003c/li\u003e\n\u003cli\u003eLim H, Devesa SS, Sosa JA, et al. Trends in Thyroid Cancer Incidence and Mortality in the United States, 1974-2013. JAMA. 2017;317(13):1338-48.\u003c/li\u003e\n\u003cli\u003eLundgren CI, Hall P, Dickman PW, et al. Clinically significant prognostic factors for differentiated thyroid carcinoma: a population-based, nested case-control study. Cancer. 2006;106(3):524-31.\u003c/li\u003e\n\u003cli\u003eNam IC, Park JO, Joo YH, et al. Pattern and predictive factors of regional lymph node metastasis in papillary thyroid carcinoma: a prospective study. Head Neck. 2013;35(1):40-5.\u003c/li\u003e\n\u003cli\u003eKoo BS, Choi EC, Park YH, et al. Occult contralateral central lymph node metastases in papillary thyroid carcinoma with unilateral lymph node metastasis in the lateral neck. J Am Coll Surg. 2010;210(6):895-900.\u003c/li\u003e\n\u003cli\u003eHaugen BR, Alexander EK, Bible KC, et al. 2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: The American Thyroid Association Guidelines Task Force on Thyroid Nodules and Differentiated Thyroid Cancer. Thyroid. 2016;26(1):1-133.\u003c/li\u003e\n\u003cli\u003eXu S, Huang H, Wang X, et al. Long-term outcomes of lobectomy for papillary thyroid carcinoma with high-risk features. Br J Surg. 2021;108(4):395-402.\u003c/li\u003e\n\u003cli\u003eXu S, Huang H, Huang Y, et al. Comparison of Lobectomy vs Total Thyroidectomy for Intermediate-Risk Papillary Thyroid Carcinoma With Lymph Node Metastasis. JAMA Surg. 2023;158(1):73-9.\u003c/li\u003e\n\u003cli\u003eZhao H, Liu CH, Cao Y, et al. An immediate postoperative response to therapy assessment can help avoid unnecessary RAI therapy. 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Occult Contralateral Lateral Lymph Node Metastases in Unilateral N1b Papillary Thyroid Carcinoma. World J Surg. 2019;43(3):818-23.\u003c/li\u003e\n\u003cli\u003eO\u0026apos;Neill RJ, Abd Elwahab S, Kerin MJ, et al. Association of BMI with Clinicopathological Features of Papillary Thyroid Cancer: A Systematic Review and Meta-Analysis. World J Surg. 2021;45(9):2805-15.\u003c/li\u003e\n\u003cli\u003eTresallet C, Seman M, Tissier F, et al. The incidence of papillary thyroid carcinoma and outcomes in operative patients according to their body mass indices. Surgery. 2014;156(5):1145-52.\u003c/li\u003e\n\u003cli\u003eKim SK, Woo JW, Park I, et al. Influence of Body Mass Index and Body Surface Area on the Behavior of Papillary Thyroid Carcinoma. Thyroid. 2016;26(5):657-66.\u003c/li\u003e\n\u003cli\u003eMatrone A, Ceccarini G, Beghini M, et al. Potential Impact of BMI on the Aggressiveness of Presentation and Clinical Outcome of Differentiated Thyroid Cancer. J Clin Endocrinol Metab. 2020;105(4).\u003c/li\u003e\n\u003cli\u003eEconomides A, Giannakou K, Mamais I, et al. Association Between Aggressive Clinicopathologic Features of Papillary Thyroid Carcinoma and Body Mass Index: A Systematic Review and Meta-Analysis. Front Endocrinol (Lausanne). 2021;12:692879.\u003c/li\u003e\n\u003cli\u003eXu L, Port M, Landi S, et al. Obesity and the risk of papillary thyroid cancer: a pooled analysis of three case-control studies. Thyroid. 2014;24(6):966-74.\u003c/li\u003e\n\u003cli\u003eRahman ST, Pandeya N, Neale RE, et al. Obesity Is Associated with BRAF(V600E)-Mutated Thyroid Cancer. Thyroid. 2020;30(10):1518-27.\u003c/li\u003e\n\u003cli\u003eSchmid D, Ricci C, Behrens G, et al. Adiposity and risk of thyroid cancer: a systematic review and meta-analysis. Obes Rev. 2015;16(12):1042-54.\u003c/li\u003e\n\u003cli\u003eKim JM. The clinical importance of overweight or obesity on tumor recurrence in papillary thyroid carcinoma. Gland Surg. 2022;11(1):35-41.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTable 1. Clinicopathological features\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eItem\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003eNumber（%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eSex\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e226（35.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eFemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e405（64.2%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eAge, y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026nbsp; Mean \u0026plusmn; SD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e38.5 \u0026plusmn; 10.9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026nbsp; Median（Range）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e36\u0026nbsp;（18-77）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026le; 45\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e456（72.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e＞45\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e175（27.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eInvolved lymph node regions in the neck\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026nbsp; central neck（VI）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e126（20.0%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026nbsp; lateral neck（II/III/IV）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e342（54.2%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003ecentral and lateral neck (VI+ II/III/IV)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e163（25.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eNo. of involved lymph node regions in the neck\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eone involved region\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e337（53.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026ge;2 involved regions\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e294（46.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eDiameter of clinical metastatic LN（cm）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e1.48 \u0026plusmn; 0.88\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026le;1cm/＞1cm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e215（34.1%）/ 416（65.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026le;2cm/＞2cm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e521（82.6%）/ 110（17.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026le;3cm/＞3cm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e605（95.9%）/ 26\u0026nbsp;（4.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eDiameter of largest tumor（cm）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e1.58 \u0026plusmn; 0.88\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026le;1cm/＞1cm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e196（31.1%）/ 435（68.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026le;2cm/＞2cm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e484（76.7%）/ 147（23.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eNumber of suspicious malignant lesions\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eMultifocality\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e141（22.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eSolitary\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e490（77.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eChronic lymphocytic thyroiditis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003ePresence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e202（32.0%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eAbsence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e429（68.0%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eBody mass index\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eUnderweight\u0026nbsp;(\u0026lt; 18.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e30\u0026nbsp;（4.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eNormal weight\u0026nbsp;(18.5~23.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e312（49.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eOverweight\u0026nbsp;(24~27.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e198（31.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eObese\u0026nbsp;(\u0026ge; 27.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e91\u0026nbsp;（14.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eBRAF mutation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eNegative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e63\u0026nbsp;（10.0%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003ePositive\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e275（43.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e292（46.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eOperation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eTT + bilateral CLND\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e126（19.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eTT + bilateral CLND+ ipsilateral LLND\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e505（80.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003ePathological subtype\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eClassic\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e522（82.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eFollicular variant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e98\u0026nbsp;（15.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eSolid variant.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e8 \u0026nbsp;（1.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eDiffuse sclerosing variant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e1 \u0026nbsp;（0.16%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eClear cell variant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e1 \u0026nbsp;（0.16%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eHobnail variant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e1 \u0026nbsp;（0.16%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eMultifocality\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003ePresence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e200（31.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eUnilateral\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e79 (12.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eBilateral\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e121 (19.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eAbsence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e431（68.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eCapsule invasion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003eAbsence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e191（30.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003ePresence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e440（69.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003ePathological LNM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;Absence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e51 (8.0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003ePresence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e580 (92%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 1-5 metastatic LNs\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e191 (33.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; ＞5 metastatic LNs\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e389 (57.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026nbsp; Ipsilateral neck\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026nbsp; Absence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e56 (8.8%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003ePresence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e575 (91.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 1-5 metastatic LNs\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e212 (33.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; ＞5 metastatic LNs\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e363 (57.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026nbsp;Contralateral neck\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Absence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e385 (61.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003ePresence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e246 (38.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 1-5 metastatic LNs\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e221 (35.0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.8878842676311%\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; ＞5 metastatic LNs\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.1121157323689%\"\u003e\n \u003cp\u003e25 (3.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eTT total thyroidectomy; CLND, central lymph node dissection; LLND, lateral lymph node dissection; NA, not available; LNs, lymph nodes.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 2. Relationship between Involved lymph node regions and postoperative pathological lymph node metastasis.\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eItem\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\"\u003e\n \u003cp\u003eInvolved lymph node regions in the neck\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e-value\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eCentral (N=126)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eLateral (N=342)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eCentral + Lateral (N=163)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003ePostoperative pathological lymph node metastasis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eIpsilateral central neck\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNumber of dissected lymph nodes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e10.98\u0026plusmn;5.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e9.19\u0026plusmn;5.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e10.77\u0026plusmn;5.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Absence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e26\u0026nbsp;（20.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e60\u0026nbsp;（17.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e14\u0026nbsp;（8.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.009\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003ePresence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e100（79.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e282（82.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e149（91.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 1-5 metastatic LNs\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e68\u0026nbsp;（54.0%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e187（54.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e69\u0026nbsp;（42.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;＞5 metastatic LNs\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e32\u0026nbsp;（25.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e95\u0026nbsp;（27.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e80\u0026nbsp;（49.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNumber of metastatic LNs of patients with pN (+)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4.76\u0026plusmn;3.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4.81\u0026plusmn;3.75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e6.68\u0026plusmn;4.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eIpsilateral lateral neck\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNumber of dissected lymph nodes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e22.85 \u0026plusmn; 11.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e24.29 \u0026plusmn; 12.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Absence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e55\u0026nbsp;（16.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e21\u0026nbsp;（12.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.347\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003ePresence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e287（83.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e142（87.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 1-5 metastatic LNs\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e192（56.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e90\u0026nbsp;（55.2%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.340\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;＞5 metastatic LNs\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e95\u0026nbsp;（27.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e52\u0026nbsp;（31.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNumber of metastatic LNs of patients with pN (+)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4.82\u0026plusmn;3.66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5.55\u0026plusmn;4.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.070\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eContralateral central neck\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNumber of dissected lymph nodes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5.61\u0026plusmn;3.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4.35 \u0026plusmn; 3.71\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4.56 \u0026plusmn; 3.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Absence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e91\u0026nbsp;（72.2%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e214（62.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e80\u0026nbsp;（49.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003ePresence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e35\u0026nbsp;（27.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e128（37.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e83\u0026nbsp;（50.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 1-5 metastatic LNs\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e33\u0026nbsp;（30.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e111（32.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e157（47.2%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.245\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;＞5 metastatic LNs\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2 \u0026nbsp;（1.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e17\u0026nbsp;（4.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e6 \u0026nbsp;（3.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNumber of metastatic LNs of patients with pN (+)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.34\u0026plusmn;1.66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.80 \u0026plusmn; 2.75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cul\u003e\n \u003cli\u003e2.48\u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;1.83\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003epN+, pathological lymph node positive; LNs, lymph nodes.\u003c/p\u003e\n\u003cp\u003eTable 3.\u0026nbsp;Univariate Logistic Regression for Contralateral Central LNM and\u0026nbsp;Ipsilateral high-volume LNMs\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003eItem\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\"\u003e\n \u003cp\u003eContralateral CLNM, no. (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003eP-value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\"\u003e\n \u003cp\u003eIpsilateral high-volume LNMs, no. (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e-value\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eAbsence（N=385）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003ePresence\u003c/p\u003e\n \u003cp\u003e（N=246）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eAbsence（N=268）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003ePresence（N=363）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eSex\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e123（54.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e103（45.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.011\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e77（33.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e150（66.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eFemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e262（64.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e143（35.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e191（47.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e213（52.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eAge, y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026le; 45\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e260（57.0%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e196（43.0%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e174（38.2%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e282（61.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e＞45\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e125（71.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e50\u0026nbsp;（28.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e94（53.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e81\u0026nbsp;（46.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eDiameter of largest tumor（cm）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026le; 1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e140（71.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e56\u0026nbsp;（28.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e105（53.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e91\u0026nbsp;（46.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e＞1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e245（56.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e190（43.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e163（37.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e272（62.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026le;2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e316（65.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e168（34.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e230（47.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e254（52.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e＞2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e69\u0026nbsp;（46.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e78\u0026nbsp;（53.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e38\u0026nbsp;（25.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e109（74.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNumber of suspicious malignant lesions\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eMultifocality\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e78\u0026nbsp;（55.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e63\u0026nbsp;（44.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.116\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e51\u0026nbsp;（44.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e90\u0026nbsp;（55.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.086\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eSolitary\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e307（62.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e183（37.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e217（36.2%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e273（63..8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eDiameter of clinical metastatic LN（cm）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026le;1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e145（67.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e70\u0026nbsp;（32.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.017\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e128（59.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e87\u0026nbsp;（40.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e＞1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e240（57.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e176（42.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e140（33.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e276（66.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eInvolved lymph node regions in the neck\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; Central\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e91\u0026nbsp;（72.2%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e35\u0026nbsp;（27.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e94（74.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e32\u0026nbsp;（25.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; Lateral\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e214（62.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e128（37.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e139（40.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e203（59.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eCentral + Lateral\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e80\u0026nbsp;（49.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e83\u0026nbsp;（50.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e35\u0026nbsp;（21.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e128\u0026nbsp;（78.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNo. of involved lymph node regions in the neck\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eone involved region\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e229（68.0%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e108（32.0%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e194（57.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e143（42.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026ge; 2 involved regions\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e156（53.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e138（46.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e74（25.2%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e220（74.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eChronic lymphocytic thyroiditis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003ePresence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e139（68.8）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e63\u0026nbsp;（31.2%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.006\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e183（42.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e246\u0026nbsp;（57.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.891\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eAbsence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e246（57.3）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e183（42.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e85\u0026nbsp;（42.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e117\u0026nbsp;（57.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eBRAF mutation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNegative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e42\u0026nbsp;（66.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e21\u0026nbsp;（33.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.080\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e19\u0026nbsp;（30.2%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e44\u0026nbsp;（69.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.162\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003ePositive\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e150（54.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e125（45.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e109（39.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e166（60.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eBody mass index\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eUnderweight\u0026nbsp;/\u0026nbsp;Normal weight\u0026nbsp;/\u0026nbsp;Overweight\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e343（63.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e197（36.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e243（45.0%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e297（55.0%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eObese\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e42（46.2%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e49（53.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e25（27.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e66（72.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eMultifocality\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003ePresence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e106（53.0%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e94\u0026nbsp;（47.0%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.016\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e79\u0026nbsp;（39.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e121\u0026nbsp;（60.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.304\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eUnilateral\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e44\u0026nbsp;（55.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e35\u0026nbsp;（44.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e24\u0026nbsp;（30.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e55\u0026nbsp;（69.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eBilateral\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e62\u0026nbsp;（51.2%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e59\u0026nbsp;（48.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e55\u0026nbsp;（45.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e66\u0026nbsp;（54.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eAbsence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e279（64.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e152（35.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e189（64.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e242（35.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eCapsule invasion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eAbsence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e120（62.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e71\u0026nbsp;（37.2%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.538\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e93（48.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e98\u0026nbsp;（51.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.037\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003ePresence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e265（60.2%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e175（39.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e175（39.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e265（60.2%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eIpsilateral pathological LNM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eAbsence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e51\u0026nbsp;（91.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5 \u0026nbsp;（8.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003ePresence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e334（58.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e241（41.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eIpsilateral pathological high-volume LNMs\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eAbsence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e212（79.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e56\u0026nbsp;（20.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003ePresence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e173（47.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e190（52.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eResponse to\u0026nbsp;therapy（n=110）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eExcellent\u0026nbsp;response\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e33（78.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e9（21.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.091\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e27（64.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e15（35.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.006\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eIndeterminate\u0026nbsp;response\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e35（62.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e21（37.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e25（44.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e31（55.4%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eBiochemical\u0026nbsp;Incomplete\u0026nbsp;response\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3（42.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4（57.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1（14.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e6（85.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eStructural\u0026nbsp;Incomplete\u0026nbsp;response\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2（40.0%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3（60.0%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0（0.0%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5（100.0%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eLN, lymph node; LNM, lymph node metastasis, LNMs, lymph node metastases\u003c/p\u003e\n\u003cp\u003eTable 4.\u0026nbsp;Multivariate Logistic Regression for Contralateral Central LNM and\u0026nbsp;Ipsilateral high-volume LNMs\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"98%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003e\u003cstrong\u003eItem\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003eSig\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003eExp(B)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e95% CI\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003e\u003cstrong\u003eContralateral CLNM\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003e\u003cstrong\u003ePreoperative factors\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e0.292\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e1.217\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e0.845-1.754\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eAge\u0026nbsp;\u0026le;\u0026nbsp;45 years old\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e1.978\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e1.339-2.924\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eTumor diameter\u0026nbsp;＞\u0026nbsp;1cm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e1.913\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e1.311-2.791\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eDiameter of involved lymph node \u0026gt;1cm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e0.230\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e1.259\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e0.864-1.835\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eChronic lymphocytic thyroiditis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e0.009\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e0.608\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e0.417-0.885\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eObese\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e0.024\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e1.745\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e1.075-2.833\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eNo. of involved lymph node regions in the neck \u0026gt; 2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e0.012\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e1.573\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e1.105-2.239\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003e\u003cstrong\u003ePostoperative factors\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e0.514\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e1.135\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e0.776-1.662\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eAge\u0026nbsp;\u0026le;\u0026nbsp;45 years old\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e0.010\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e1.711\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e1.138-2.571\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eTumor diameter\u0026nbsp;＞\u0026nbsp;1cm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e0.004\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e1.780\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e1.203-2.635\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eChronic lymphocytic thyroiditis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e0.006\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e0.577\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e0.392-0.851\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eObese\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e0.106\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e1.514\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e0.915-2.504\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eMultifocality\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e0.018\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e1.568\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e1.082-2.272\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eIpsilateral pathological high-volume LNMs\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e3.636\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e2.501-5.284\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003e\u003cstrong\u003eIpsilateral high-volume LNMs\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003ePreoperative factors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e0.042\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e1.482\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e1.014-2.164\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eAge\u0026nbsp;\u0026le;\u0026nbsp;45 years old\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e1.994\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e1.354-2.937\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eTumor diameter\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e＞\u0026nbsp;1cm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e1.798\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e1.237-2.615\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eDiameter of involved lymph node \u0026gt; 1cm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e2.071\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e1.426-3.007\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eObese\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e0.032\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e1.828\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e1.052-3.177\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"57.142857142857146%\"\u003e\n \u003cp\u003eNo. of involved lymph node regions in the neck\u0026nbsp;\u0026ge;2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.26530612244898%\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.285714285714286%\"\u003e\n \u003cp\u003e3.196\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.306122448979592%\"\u003e\n \u003cp\u003e2.218-4.605\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eCLNM, central lymph node metastasis; LNM, lymph node metastasis; LNMs, lymph node metastases\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"world-journal-of-surgical-oncology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"wjso","sideBox":"Learn more about [World Journal of Surgical Oncology](http://wjso.biomedcentral.com)","snPcode":"12957","submissionUrl":"https://submission.nature.com/new-submission/12957/3","title":"World Journal of Surgical Oncology","twitterHandle":"@OncoBioMed","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"papillary thyroid carcinoma, occult lymph node metastasis, lymph node dissection, pattern, predictive factors","lastPublishedDoi":"10.21203/rs.3.rs-4210730/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4210730/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eNo significant difference in disease-specific survival and recurrence-free survival exists between papillary thyroid cancer (PTC) patients with high-risk features subjected to lobectomy and thyroidectomy. However, it is unclear which type of patients with unilateral PTC combined with ipsilateral clinical involved lymph nodes (cN1) can receive a less aggressive treatment.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eWe collected the medical records of 631 patients diagnosed with unilateral PTC and ipsilateral cN1. These patients initially underwent total thyroidectomy and bilateral central lymph node dissection (LND), with or without lateral LND. We conducted an analysis to investigate the associations between contralateral occult central lymph node metastasis (CLNM) and clinicopathologic factors.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe proportion of contralateral occult CLNM was 38.9%. age\u0026thinsp;\u0026le;\u0026thinsp;45 years, tumor diameter\u0026thinsp;\u0026gt;\u0026thinsp;1 cm, obesity, and involvement of lymph node regions\u0026thinsp;\u0026ge;\u0026thinsp;2 were independent risk factors for contralateral occult CLNM. Multifocality and ipsilateral neck high-volume lymph node metastases were independent risk factors among the postoperative pathological factors. A predicting model was developed to quantify the risk of each factor, which revealed that patients without any of the risk factors mentioned above had a 20\u0026ndash;30% probability of contralateral occult CLNM, whereas the probability was greater than 60% when all factors were present.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eAlthough the rate of contralateral occult CLNM was not low in patients with unilateral PTC combined with ipsilateral cN1, the scope of surgery could be reduced for non-obese patients with over 45 years old, tumor diameter\u0026thinsp;\u0026le;\u0026thinsp;1 cm, and only one preoperative lymph node region involved.\u003c/p\u003e","manuscriptTitle":"Pattern and predictive factors of occult contralateral central lymph node metastases in unilateral papillary thyroid carcinoma with ipsilateral clinical lymph node metastasis","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-04-11 17:36:44","doi":"10.21203/rs.3.rs-4210730/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorAssigned","content":"","date":"2024-04-06T13:00:55+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-04-04T14:51:29+00:00","index":"","fulltext":""},{"type":"submitted","content":"World Journal of Surgical Oncology","date":"2024-04-03T07:27:20+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"world-journal-of-surgical-oncology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"wjso","sideBox":"Learn more about [World Journal of Surgical Oncology](http://wjso.biomedcentral.com)","snPcode":"12957","submissionUrl":"https://submission.nature.com/new-submission/12957/3","title":"World Journal of Surgical Oncology","twitterHandle":"@OncoBioMed","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"a096b1d1-61f1-42a2-ae8c-544165c61e16","owner":[],"postedDate":"April 11th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2024-04-11T17:36:44+00:00","versionOfRecord":[],"versionCreatedAt":"2024-04-11 17:36:44","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4210730","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4210730","identity":"rs-4210730","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}