Sufficient Intraoperative Exposure of Parathyroid Glands Protects Long‑Term Parathyroid Function After Total Thyroidectomy plus Central Lymph Node Dissection for Papillary Thyroid Carcinoma

Sufficient Intraoperative Exposure of Parathyroid Glands Protects Long‑Term Parathyroid Function After Total Thyroidectomy plus Central Lymph Node Dissection for Papillary Thyroid Carcinoma | 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 Sufficient Intraoperative Exposure of Parathyroid Glands Protects Long‑Term Parathyroid Function After Total Thyroidectomy plus Central Lymph Node Dissection for Papillary Thyroid Carcinoma Xinguang Jin, Zehang Xu, Liping Wen, Xianmeng Chen, Weibin Wang, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7446726/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 10 You are reading this latest preprint version Abstract Background: Hypoparathyroidism (HypoPT) is the most common complication after total thyroidectomy (TT) and central lymph node dissection (CLND) for thyroid carcinoma. However, there’s still no effective surgical strategy to prevent its incidence. This study evaluated the impact of sufficient intraoperative exposure of the parathyroid glands (PG) on postoperative parathyroid function, the rate of parathyroid autotransplantation, and incidental parathyroidectomy. Methods: Prospective data from 133 consecutive patients who underwent TT and CLND by a single surgeon at the First Affiliated Hospital of Zhejiang University School of Medicine were systematically collected. All patients were categorized into sufficient exposure (exposed) group and insufficient exposure (control) group based on whether all 4 PGs were identified during surgery. PG exposure and autotransplantation were recorded intraoperatively, while incidental parathyroidectomy was determined via routine pathology reports. Postoperative parathyroid hormone (PTH) levels, serum calcium levels, and hypocalcemia-related symptoms (limb numbness/tetany) were monitored for at least six months. Continuous variables were compared using independent samples t-test for normally distributed data., while categorical variables were analyzed using Pearson’s chi-square test. A two-sided P-value < 0.05 was considered statistically significant. Results: No patients in the sufficient exposure group developed permanent hypoPT, while 2 patients in the insufficient exposure group exhibited biochemical hypoPT. Mean PTH levels were significantly higher in the sufficient exposure group (33.22 ± 16.48 pg/ml vs. 26.48 ± 10.94 pg/ml, P = 0.048) within six months. Parathyroid autotransplantation was more frequent in the sufficient exposure group (26.0% vs. 8.3%, P = 0.008). For transient hypoPT, incidental parathyroidectomy or clinical symptoms, there was no significant difference between groups (P > 0.05). Conclusion: Sufficient exposure of the PGs during surgery can potentially protect parathyroid function in terms of PTH level without increasing transient hypoPT, indicating PG sufficient exposure is a practical way to protect parathyroid function. Hypoparathyroidism Parathyroid Gland Preservation Total Thyroidectomy Parathyroid Autotransplantation Figures Figure 1 1. Introduction Hypoparathyroidism (HypoPT) is the most common complication following total thyroidectomy (TT), with 20–30% of patients experiencing transient hypoPT and 0.8–7.3% developing permanent hypoPT. 1 – 4 In patients with thyroid carcinoma undergoing prophylactic or therapeutic central lymph node dissection (CLND), the incidence rates can further increase to at least 14% for transient hypoPT, while permanent hypoPT may even reach up to 16.2%. 5–7 Reasons of postoperative hypoPT include intraoperative parathyroid glands (PG) mechanical injury, such as incidental parathyroidectomy, traction, compression, and interruption of the gland's blood supply. 8 , 9 It commonly presents with acute hypocalcemia symptoms due to decreased parathyroid hormone (PTH) levels, characterized by neuromuscular hyperexcitability, such as limb numbness and tetany. These symptoms severely affect postoperative quality of life and increase the financial burden on patients, especially in cases of permanent hypoPT. Long-term consequences of permanent hypoPT include chronic kidney disease, basal ganglia calcification, and an increased risk of infections, further complicating patient outcomes. Therefore, preventing postoperative hypoPT is an urgent concern for thyroid surgeons. 1 , 10 , 11 The debate remains on whether more extensive exposure of the PGs during surgery causes more damage or offers better protection. Some studies suggest that active identification and preservation of PGs can reduce the risk of incidental parathyroidectomy and improve long-term gland function. 2 , 3 , 12 Conversely, other reports indicate that excessive manipulation may compromise the gland’s vascular supply, leading to transient or permanent dysfunction. 13 , 14 Current literature presents mixed conclusions regarding whether PGs should be actively exposed and fully identified during thyroid surgery. The American Thyroid Association (ATA) statement on postoperative hypoparathyroidism emphasizes the need for standardized surgical approaches to mitigate the risk of hypoPT but does not provide a consensus on the degree of PG exposure required during thyroidectomy. 1 This current study is to explore the impact of all 4 PGs exposure on postoperative parathyroid function, focusing on both transient and permanent hypoPT outcomes. 2. Materials and methods 2.1. Study design This prospective study analyzed data from patients undergoing TT and CLND (including lateral lymph node dissection, LLND) at the Department of Surgical Oncology, First Affiliated Hospital of Zhejiang University School of Medicine, between January 2020 and June 2024. A total of 211 patients were initially enrolled, all of whom were over 18 years old and operated on by a single surgeon to ensure consistency in surgical technique. A comprehensive thyroid surgery database was established and regularly updated to include surgical details, preoperative and postoperative laboratory tests, and pathological findings, such as intraoperative PG exposure, gland location, evidence of damage or excision, serum calcium levels, and parathyroid hormone (PTH) concentrations. Patients were divided into two groups according to whether the PGs were systematically exposed: the sufficient exposure group (all 4 PGs exposed) and the insufficient exposure group (fewer than 4 glands exposed). The primary outcomes assessed were hypoPT, categorized as transient or permanent (with a 6-month cutoff), intraoperative parathyroid autotransplantation, and incidental parathyroidectomy (defined as parathyroid tissue identified in routine pathology reports without prior autotransplantation). HypoPT was further classified as biochemical hypoPT (PTH < 12 pg/mL accompanied by new-onset hypocalcemia, defined as serum calcium < 2.11 mmol/L) or clinical hypoPT (biochemical hypoPT with associated symptoms and/or signs of hypocalcemia). 1 Exclusion criteria included a history of thyroid surgery, preoperative thyroid or parathyroid dysfunction, distant metastasis, and incomplete follow-up data. After applying these criteria, 133 patients were included in the final analysis, allowing for a focused evaluation of the relationship between PG exposure and postoperative outcomes. 2.2. Surgical Technique Thyroidectomies were performed using the capsular dissection technique. This method involves careful dissection of the soft tissue from the thyroid capsule to preserve the PGs in situ after retraction of the fascia and muscles and elevation of the thyroid’s upper and lower poles. Special attention was given to identifying PGs located on or adjacent to the thyroid capsule, particularly near the Zuckerkandl tubercle and the recurrent laryngeal nerve. 13 Once identified, the PGs were meticulously dissected away from the thyroid while preserving their vascular supply as much as possible. Each operation aimed to expose all 4 PGs. Thyroidectomy specimens were carefully examined to identify PGs that were either adherent to or embedded within the thyroid tissue. Similarly, the thyroid bed was inspected for PGs that were completely devascularized or appeared discolored. As described, any devascularized or discolored glands, as well as inadvertently excised parathyroid tissue, were autotransplanted into the ipsilateral sternocleidomastoid muscle. 15 , 16 All autotransplanted PGs were confirmed intraoperatively by frozen section analysis of a representative portion of the excised tissue. Central neck dissection (level VI) was performed en bloc, extending from the hyoid bone to the innominate vein and laterally to the carotid sheaths, including prelaryngeal, pretracheal, and bilateral paratracheal nodes. Lateral neck dissection (levels II–Vb) involved systematic removal of fibrofatty tissue within anatomical compartments, preserving the sternocleidomastoid muscle, internal jugular vein, and spinal accessory nerve. Dissection proceeded from level IIa superiorly to level Vb inferiorly, guided by preoperative imaging and intraoperative findings. 17 , 18 Each nodal basin was submitted separately for pathological evaluation. 2.3. Data Collection Collected data included patient demographics (gender, age, medical history), preoperative and postoperative laboratory values (PTH, serum calcium, phosphorus, magnesium, and potassium levels), and surgical details (extent of surgery—number of PGs exposed intraoperatively, whether CLND or LLND was performed, and whether parathyroid autotransplantation was conducted). Clinical follow-up data were gathered through outpatient visits and telephone consultations, with a minimum follow-up duration of six months for all patients. Patients were considered lost to follow-up if three telephone attempts at different times were unsuccessful. The presence of incidental parathyroidectomy was initially identified by reviewing postoperative pathology reports and was further corroborated through cross-referencing with surgical records, intraoperative frozen section analyses, and final pathology evaluations. This multilayered verification aimed to enhance the accuracy of incidental parathyroidectomy detection and minimize reporting errors. 2.4. Statistical Analysis Data were analyzed using SPSS version 27.0. Descriptive statistics, including counts and percentages, were employed to summarize patient characteristics and surgical outcomes. Continuous variables were compared using independent samples t-tests, while categorical variables were analyzed with chi-square tests in univariate analyses. A two-sided significance threshold was set at 0.05 for all statistical tests. All the figures in this article were drawn using Python 3.10.13. 3. Results 3.1. Baseline Characteristics of the Patients Enrolled The baseline characteristics and relevant laboratory test results of the enrolled patients are summarized in Table 1. A total of 133 patients undergoing total thyroidectomy were included in the final analysis. All patients were newly diagnosed, over 18 years of age, and had confirmed malignant tumors via postoperative pathological examination. All patients underwent lymph node dissection. The mean age was 45.4 ± 11.2 years, with a predominance of female patients (90/133, 67.7%). Patients were stratified into two groups: the sufficient exposure group (all 4 PGs exposed intraoperatively) and the insufficient exposure group (fewer than 4 glands exposed). No significant differences were observed between the two groups concerning age, gender, tumor multifocality, bilaterality, lymph node dissection extent, capsule invasion, extrathyroidal extension, TNM stage, or history of radioactive iodine treatment (P > 0.05). Table 1. Baseline characteristics of patients enrolled. Variables Classification All cases (N =133, %) Sufficient exposure P Yes (N=73, %) No (N=60, %) Total 133(100) 73(100) 60(100) Gender Male 43(32.3) 24(32.9) 19(31.7) 0.882 Female 90(67.7) 49(67.1) 41(68.3) Age ＜55y 99(74.4) 57(78.1) 42(70) 0.288 ≥55y 34(25.6) 16(21.9) 18(30) No. of parathyroids exposure 2 11(8.3) 0(0) 11(18.3) NA 3 49(36.8) 0(0) 49(81.7) 4 73(54.9) 73(100) 0(0) Multifocality Yes 83(62.4) 46(63) 37(61.7) 0.873 No 50(37.6) 27(37) 23(38.3) Bilaterality Yes 75(56.4) 43(58.9) 32(53.3) 0.519 No 58(43.6) 30(41.1) 28(46.7) Lymph node dissection CLND 104(78.2) 56(76.7) 48(80) 0.648 CLND+LLND 29(21.8) 17(23.3) 12(20) Capsule invasion Yes 96(72.2) 52(71.2) 44(73.3) 0.788 No 37(27.8) 21(28.8) 16(26.7) gETE Yes 15(11.3) 9(12.3) 6(10) 0.673 No 118(88.7) 64(87.7) 54(90) T stage T1 101(75.9) 57(78.1) 44(73.3) 0.267 T2 8(6) 6(8.2) 2(3.3) T3+T4 24(18) 10(13.7) 14(23.3) N stage N0 56(42.1) 32(43.8) 24(40) 0.410 N1a 50(37.6) 24(32.9) 26(43.3) N1b 27(20.3) 17(23.3) 10(16.7) Abbreviation: CLND, central lymph node dissection; LLND, lateral lymph node dissection; gETE, gross extrathyroidal extension; NA, not available 3.2. Parathyroid Function in Both Groups Among the 133 patients, the sufficient exposure group demonstrated a transient biochemical hypoPT rate of 15.1% (n=11/73) compared to 16.7% (n=10/60) in the insufficient exposure group (P=0.801). Similarly, clinical manifestations of transient hypoPT were observed in 9.6% (n=7/73) of the sufficient exposure group versus 11.7% (n=7/60) of the insufficient exposure group (P=0.698). Regarding permanent hypoparathyroidism, the insufficient exposure group showed a 3.3% incidence rate (n= 2/60) for biochemical hypoparathyroidism, while no cases (0%) were identified in the sufficient exposure group (P=0.202). Neither group reported any cases of clinically apparent permanent hypoPT (Table 2). Table 2. Incidence of postoperative complications according to parathyroid gland sufficient exposure. Complications Sufficient exposure P Yes (N=73, %) No (N=60, %) Transient changes (<6months) Biochemical hypoPT 11(15.1) 10(16.7) 0.801 Clinical hypoPT 7(9.6) 7(11.7) 0.698 Hypocalcemia 22(30.1) 21(35) 0.551 PTH level(<12pg/ml) 39(53.4) 28(46.7) 0.438 Numbness/Tetany 13(17.8) 10(16.7) 0.862 Permanent changes (≥6 months) Biochemical hypoPT 0(0) 2(3.3) 0.202 Clinical hypoPT 0(0) 0(0) NA Hypocalcemia 2(2.7) 5(8.3) 0.243 PTH level(<12ng/ml) 2(2.7) 2(3.3) 1.000 Numbness/Tetany 1(1.4) 2(3.3) 0.589 Abbreviations: hypoPT, hypoparathyroidism; PTH, parathyroid hormone; NA, not available Follow-up analyses of PTH and serum calcium levels showed no significant differences between the two groups at 1 day, 1 month, and 3 months postoperatively. However, at 6 months post-surgery, PTH levels were significantly higher in the sufficient exposure group (33.22 ± 16.48 pg/ml vs. 26.48 ± 10.94 pg/ml, P = 0.048) (Figure 1). 3.3. Parathyroid Autotransplantation in Both Groups Intraoperative parathyroid autotransplantation was performed in 24 patients (18.0%). Of these, 19 cases occurred in the sufficient exposure group, while only 5 cases were reported in the insufficient exposure group. The sufficient exposure group, which showed a significantly higher rate of autotransplantation (26.0% vs. 8.3%, P = 0.008), was associated with more timely intraoperative identification of compromised PGs. However, parathyroid autotransplantation was found significantly associated with a higher incidence of clinical symptoms within 6 months (37.5% vs. 12.8%, P = 0.007) and transient clinical hypoPT specifically (25.0% vs. 7.3%, P = 0.021) (Table 3), but no significant differences were observed in PTH and serum calcium levels between patients who underwent autotransplantation and those who did not within the first six months postoperatively (P > 0.05). Table 3. Incidence of postoperative outcomes according to number of parathyroid autotransplantation. Complications Parathyroid autotransplantation P Yes (N=24, %) No (N=109, %) Transient changes (<6months) Biochemical hypoPT 2(8.3) 19(17.4) 0.364 Clinical hypoPT 6(25) 8(7.3) 0.021 Hypocalcemia 4(16.7) 39(35.8) 0.070 PTH level(<12pg/ml) 13(54.2) 56(51.4) 0.804 Numbness/Tetany 9(37.5) 14(12.8) 0.007 Permanent changes (≥6 months) Biochemical hypoPT1 0(0) 2(1.8) 1.000 Clinical hypoPT 0(0) 0(0) NA Hypocalcemia 3(12.5) 4(3.7) 0.111 PTH level(<12ng/ml) 2(8.3) 2(1.8) 0.149 Numbness/Tetany 1(4.2) 2(1.8) 0.452 Abbreviations: hypoPT, hypoparathyroidism; PTH, parathyroid hormone; NA, not available 3.4. Rate of Incidental Parathyroidectomy in Both Groups Chi-square analysis indicated no significant difference in the occurrence of incidental parathyroidectomy between the sufficient and insufficient exposure groups (17.8% vs. 18.3%, P = 0.938). The overall incidence of incidental parathyroidectomy was 17.8%(n=13/73). The accuracy of visual identification for PGs during thyroidectomy was 82.2%, as determined by postoperative pathological confirmation. 4. Discussion In this prospective study including 133 patients who underwent TT and CLND, exposure of all 4 PGs neither increased transient hypoPT (15.1 % vs. 16.7 %; P = 0.801) nor permanent hypoPT (0 % vs. 3.3 %; P=0.202). More importantly, the fully exposed cohort exhibited a higher mean serum PTH concentration at six months (33.2 ± 16.5 vs. 26.5 ± 10.9 pg/mL; P = 0.048), underscoring that deliberate visualization safeguards immediate endocrine integrity and accelerates long-term functional recovery. To our knowledge, this is the first report confined to a TT + CLND population, a setting intrinsically more demanding than the mixed or pure thyroidectomy cohorts previously studied. The safety signal we observed echoes findings from Mehta et al. (transient hypocalcemia 18.0 % with ≥2 glands identified vs. 19.2 % with ≤1 gland; P = 0.84) and Sitges-Serra et al. (14.3 % vs. 15.8 %; P = 0.78), whereas Riordan et al. linked identification of ≥3 glands to a 70 % higher odds of biochemical hypocalcemia (OR 1.7, 95 % CI 1.1–2.9). That series, however, excluded CLND, thereby examining a less complex surgical situation. Our data therefore extend earlier work by demonstrating that, even under the heightened ischemic risk imposed by CLND, visualization does not confer harm and may in fact be protective. Systematic exposure inevitably heightened intra-operative recognition of devascularized glands, yielding a higher autotransplantation rate in our cohort (26.0 % vs. 8.3 %). Although graft recipients experienced more transient symptomatic hypocalcemia, this trade-off mirrors prior endoscopic TT + CLND data—Cheng et al. reported a similar early dip in PTH yet no disadvantage beyond the first postoperative week. 19 By 1 month, re-implanted tissue begins secreting hormone; experimental perfusion studies show functional recovery is largely complete within 4–8 weeks, with serum PTH rising in parallel. 20 Consistent with these kinetics, a population study of 342 thyroidectomies found that autotransplantation shortened the median time to biochemical normalization from 32 days to 7 days and eliminated permanent hypoPT. 21 By contrast, two recent single-center analyses failed to demonstrate a reduction in permanent disease; their cohorts transplanted predominantly “doubtful” tissue after prolonged manipulation, a practice associated with lower graft viability. 22,23 Collectively, prompt reimplantation of PGs effectively speed endocrine recovery and may avert permanent hypoPT. This study has several limitations. As a single-center study, the findings may not be generalizable to broader clinical settings. In addition, the relatively small number of patients with permanent hypoPT limited the ability to draw definitive conclusions regarding long-term outcomes. Larger, multicenter studies with extended follow-up are needed to validate these results and to further investigate factors influencing postoperative parathyroid function. 5. Conclusion In patients undergoing TT+CLND for thyroid cancer, sufficient exposure of PGs is beneficial to the recovery of postoperative PTH level, and does not increase the incidence of temporary hypoPT. While our findings support the safety of sufficient PG exposure in CLND-containing procedures, future studies should aim to establish the optimal balance between adequate visualization for gland preservation and excessive dissection that might compromise vascular integrity. Declarations Ethical approval This study was conducted following the ethical standards of the 1964 Declaration of Helsinki and approved by the Ethics Review Committee of the First Affiliated Hospital of Zhejiang University, Ethical approval number: [2025B] IIT Ethics Approval No.0386. Clinical trial number Not applicable. Consent to Publish declaration Not applicable. Author Disclosure Statement Xinguang Jin, Zehang Xu, Liping Wen, Xianmeng Chen, Weibin Wang, Shitu Chen, Haijie Huang, Lisong Teng, and Xiongfei Yu declare no conflicts of interest and no competing financial interests exist. Consent to participate Informed consent was obtained from all participants of the study. Data Availability Statement The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions. Funding This research was supported by Zhejiang Medical Association Clinical Medicine Research Special Fund Project (No.2022ZYC-A200) . References Orloff, L. A. et al. American Thyroid Association Statement on Postoperative Hypoparathyroidism: Diagnosis, Prevention, and Management in Adults. Thyroid 28 , 830–841 (2018). Ponce De León-Ballesteros, G. et al. Hypoparathyroidism After Total Thyroidectomy: Importance of the Intraoperative Management of the Parathyroid Glands. World J. Surg. 43 , 1728–1735 (2019). Pattou, F. et al. Hypocalcemia following Thyroid Surgery: Incidence and Prediction of Outcome. World J. Surg. 22 , 718–724 (1998). Rafferty, M. A. et al. Completion Thyroidectomy Versus Total Thyroidectomy: Is There a Difference in Complication Rates? An Analysis of 350 Patients. J. Am. Coll. Surg. 205 , 602–607 (2007). Sitges-Serra, A. Etiology and Diagnosis of Permanent Hypoparathyroidism after Total Thyroidectomy. J. Clin. Med. 10 , 543 (2021). Hundahl, S. A. et al. Initial results from a prospective cohort study of 5583 cases of thyroid carcinoma treated in the United States during 1996: An American College of Surgeons Commission on Cancer patient care evaluation study. Cancer 89 , 202–217 (2000). Su, A. et al. Risk factors of hypoparathyroidism following total thyroidectomy with central lymph node dissection. Medicine (Baltimore) 96 , e8162 (2017). Thomusch, O. et al. Multivariate Analysis of Risk Factors for Postoperative Complications in Benign Goiter Surgery: Prospective Multicenter Study in Germany. World J. Surg. 24 , 1335–1341 (2000). Winged, D. J., Friesen, S. R., Ilkqoulos, J. I., Pierce, G. E. & Thomas, J. H. Post-Thyroidectomy tiypocalcemia. Am. J. Surg. Dolores, S. Hypoparathyroidism. N. Engl. J. Med. (2008). Wang, X. et al. Postoperative hypoparathyroidism after thyroid operation and exploration of permanent hypoparathyroidism evaluation. Front. Endocrinol. 14 , 1182062 (2023). Thomusch, O. et al. The impact of surgical technique on postoperative hypoparathyroidism in bilateral thyroid surgery: A multivariate analysis of 5846 consecutive patients. Surgery 133 , 180–185 (2003). Riordan, F., Murphy, M. S., Feeley, L. & Sheahan, P. Association between number of parathyroid glands identified during total thyroidectomy and functional parathyroid preservation. Langenbecks Arch. Surg. 407 , 297–303 (2022). Sheahan, P., Mehanna, R., Basheeth, N. & Murphy, M. S. Is systematic identification of all four parathyroid glands necessary during total thyroidectomy?: A prospective study: Identifying Parathyroid During Thyroidectomy. The Laryngoscope 123 , 2324–2328 (2013). Lorente-Poch, L., Sancho, J. J., Ruiz, S. & Sitges-Serra, A. Importance of in situ preservation of parathyroid glands during total thyroidectomy. Br. J. Surg. 102 , 359–367 (2015). Mehta, S., Dhiwakar, M. & Swaminathan, K. Outcomes of parathyroid gland identification and autotransplantation during total thyroidectomy. Eur. Arch. Otorhinolaryngol. 277 , 2319–2324 (2020). Haugen, B. R. 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 26 , 1–133 (2016). Randolph, G. W. et al. The Prognostic Significance of Nodal Metastases from Papillary Thyroid Carcinoma Can Be Stratified Based on the Size and Number of Metastatic Lymph Nodes, as Well as the Presence of Extranodal Extension. Thyroid 22 , 1144–1152 (2012). Cheng, X., Li, Y. & Chen, L. Efficacy of parathyroid autotransplantation in endoscopic total thyroidectomy with CLND. Front. Endocrinol. 14 , 1193851 (2023). Ge, G. et al. Effectiveness of parathyroid autotransplantation during total thyroidectomy and functional recovery post-operation: A retrospective study. Eur. J. Surg. Oncol. 51 , 110007 (2025). Yazıcıoğlu, M. Ö., Yılmaz, A., Kocaöz, S., Özçağlayan, R. & Parlak, Ö. Risks and prediction of postoperative hypoparathyroidism due to thyroid surgery. Sci. Rep. 11 , 11876 (2021). Kasmirski, J. A. et al. Does Parathyroid Autotransplantation Prevent Hypoparathyroidism after Thyroid Surgery? Ann. Surg. (2025) doi:10.1097/SLA.0000000000006631. Koimtzis, G., Stefanopoulos, L., Geropoulos, G. & Papavramidis, T. The outcomes of parathyroid gland autotransplantation during thyroid surgery: a systematic review, meta-analysis and trial sequential analysis. Endocrine 87 , 27–38 (2024). Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 24 Feb, 2026 Reviews received at journal 24 Feb, 2026 Reviewers agreed at journal 18 Feb, 2026 Reviews received at journal 03 Oct, 2025 Reviewers agreed at journal 23 Sep, 2025 Reviewers invited by journal 18 Sep, 2025 Editor invited by journal 03 Sep, 2025 Editor assigned by journal 30 Aug, 2025 Submission checks completed at journal 30 Aug, 2025 First submitted to journal 24 Aug, 2025 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-7446726","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":516883060,"identity":"530275e2-ec46-457e-9f94-bffa2d89d997","order_by":0,"name":"Xinguang Jin","email":"","orcid":"","institution":"Zhejiang University","correspondingAuthor":false,"prefix":"","firstName":"Xinguang","middleName":"","lastName":"Jin","suffix":""},{"id":516883063,"identity":"af07c21f-7963-48cc-858c-b4f92b925a43","order_by":1,"name":"Zehang Xu","email":"","orcid":"","institution":"Zhejiang University","correspondingAuthor":false,"prefix":"","firstName":"Zehang","middleName":"","lastName":"Xu","suffix":""},{"id":516883065,"identity":"2d1c13b7-8c0a-4785-8e88-7db8f3193d45","order_by":2,"name":"Liping Wen","email":"","orcid":"","institution":"Zhejiang University","correspondingAuthor":false,"prefix":"","firstName":"Liping","middleName":"","lastName":"Wen","suffix":""},{"id":516883066,"identity":"5aa0f4a6-8787-4548-9334-2db35ee154e2","order_by":3,"name":"Xianmeng Chen","email":"","orcid":"","institution":"Zhejiang University","correspondingAuthor":false,"prefix":"","firstName":"Xianmeng","middleName":"","lastName":"Chen","suffix":""},{"id":516883067,"identity":"d81b9ae8-f8e0-41c0-8dbb-95c012cb919e","order_by":4,"name":"Weibin Wang","email":"","orcid":"","institution":"Zhejiang University","correspondingAuthor":false,"prefix":"","firstName":"Weibin","middleName":"","lastName":"Wang","suffix":""},{"id":516883068,"identity":"e8fe7866-0f94-4923-9284-b9bece84086f","order_by":5,"name":"Shitu Chen","email":"","orcid":"","institution":"Zhejiang University","correspondingAuthor":false,"prefix":"","firstName":"Shitu","middleName":"","lastName":"Chen","suffix":""},{"id":516883070,"identity":"e9ac2160-84fa-40bb-8f03-b7457da19fdf","order_by":6,"name":"Haijie Huang","email":"","orcid":"","institution":"Haining People’s Hospital","correspondingAuthor":false,"prefix":"","firstName":"Haijie","middleName":"","lastName":"Huang","suffix":""},{"id":516883071,"identity":"bbaea4b5-8f28-42f7-b963-4cb0b6685dac","order_by":7,"name":"Lisong Teng","email":"","orcid":"","institution":"Zhejiang University","correspondingAuthor":false,"prefix":"","firstName":"Lisong","middleName":"","lastName":"Teng","suffix":""},{"id":516883072,"identity":"d18980d4-1347-43ee-ba8b-23a681130b2d","order_by":8,"name":"Xiongfei Yu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAy0lEQVRIiWNgGAWjYBACNmbGhgMJPDZyDAwHQFwitPCxMx988EEmzZh4LXL8bMmGM2wOJTZALCXKYTxm0jw5B9LnN54xYPhQdpiBf3YDMVrO3MltbDhjwDjj3GEGiTsHiNDC2/Mst5nhjAEzb9thBgOJBGK0/DuczgbS8pc4LSDv8xxO4AFpYSROCyiQedIMZzAcKzjYcy6dR+IGAS3y/QfBUSkvP+Pwxgc/yqzl+GcQ0IIAEgfAkclDrHog4G8gQfEoGAWjYBSMKAAAEPxASkfzK+YAAAAASUVORK5CYII=","orcid":"","institution":"Zhejiang University","correspondingAuthor":true,"prefix":"","firstName":"Xiongfei","middleName":"","lastName":"Yu","suffix":""}],"badges":[],"createdAt":"2025-08-24 14:23:14","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7446726/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7446726/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":91815422,"identity":"18e7ce5b-425a-4257-9c6f-064a13500f4c","added_by":"auto","created_at":"2025-09-22 06:24:59","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":184646,"visible":true,"origin":"","legend":"","description":"","filename":"Textrevisedver.2.docx","url":"https://assets-eu.researchsquare.com/files/rs-7446726/v1/8df9cc1484a7452c7504e1f0.docx"},{"id":91815887,"identity":"5491a80c-fa76-4e48-b423-accf05f3dfd4","added_by":"auto","created_at":"2025-09-22 06:32:59","extension":"json","order_by":1,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":10450,"visible":true,"origin":"","legend":"","description":"","filename":"762cb6b11ba84e3c865c48da1a2faeff.json","url":"https://assets-eu.researchsquare.com/files/rs-7446726/v1/88683b48b97a582b9d210aa2.json"},{"id":91815425,"identity":"d1ae016f-8c13-47e5-8613-4138529e48d0","added_by":"auto","created_at":"2025-09-22 06:24:59","extension":"xml","order_by":2,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":82425,"visible":true,"origin":"","legend":"","description":"","filename":"762cb6b11ba84e3c865c48da1a2faeff1enriched.xml","url":"https://assets-eu.researchsquare.com/files/rs-7446726/v1/04c414d695742f16598e5d96.xml"},{"id":91815888,"identity":"c53d2735-7c6f-4600-9ca5-15897e7bb58d","added_by":"auto","created_at":"2025-09-22 06:32:59","extension":"jpeg","order_by":3,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":110200,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7446726/v1/ed64494b1bef723abc820f45.jpeg"},{"id":91815890,"identity":"561bef05-a4d4-4003-bda9-bf6eeaac9234","added_by":"auto","created_at":"2025-09-22 06:32:59","extension":"png","order_by":4,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":82904,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-7446726/v1/54d66ea7cc3129209ee26e8a.png"},{"id":91815448,"identity":"7e276f1c-0e3f-4f39-add6-876f6c0bd841","added_by":"auto","created_at":"2025-09-22 06:24:59","extension":"xml","order_by":5,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":79970,"visible":true,"origin":"","legend":"","description":"","filename":"762cb6b11ba84e3c865c48da1a2faeff1structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-7446726/v1/a1214841da4c51b87d331be3.xml"},{"id":91815891,"identity":"b4110abb-0307-48d0-8748-b2046b582a43","added_by":"auto","created_at":"2025-09-22 06:33:00","extension":"html","order_by":6,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":89141,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7446726/v1/02f3b0fb7cec2f1aa72e2935.html"},{"id":91815420,"identity":"2e58a4e3-81ca-404e-b775-a0bb943409e8","added_by":"auto","created_at":"2025-09-22 06:24:59","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":132909,"visible":true,"origin":"","legend":"\u003cp\u003ePTH and serum calcium values before and after surgery. (a) PTH level. (b) Serum calcium level. The asterisk (*) denotes P value less than 0.05. Abbreviation: PTH, parathyroid hormone\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7446726/v1/f258558566751131166e801c.jpeg"},{"id":91816447,"identity":"08c68b0c-a954-4fe9-97af-18c38ed3078f","added_by":"auto","created_at":"2025-09-22 06:40:59","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":987058,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7446726/v1/cef87a62-c7fc-4ba3-a2c7-3e8a79dbfc91.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Sufficient Intraoperative Exposure of Parathyroid Glands Protects Long‑Term Parathyroid Function After Total Thyroidectomy plus Central Lymph Node Dissection for Papillary Thyroid Carcinoma","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eHypoparathyroidism (HypoPT) is the most common complication following total thyroidectomy (TT), with 20\u0026ndash;30% of patients experiencing transient hypoPT and 0.8\u0026ndash;7.3% developing permanent hypoPT.\u003csup\u003e\u003cspan additionalcitationids=\"CR2 CR3\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e In patients with thyroid carcinoma undergoing prophylactic or therapeutic central lymph node dissection (CLND), the incidence rates can further increase to at least 14% for transient hypoPT, while permanent hypoPT may even reach up to 16.2%.\u003csup\u003e5\u0026ndash;7\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eReasons of postoperative hypoPT include intraoperative parathyroid glands (PG) mechanical injury, such as incidental parathyroidectomy, traction, compression, and interruption of the gland's blood supply.\u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e,\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u003c/sup\u003e It commonly presents with acute hypocalcemia symptoms due to decreased parathyroid hormone (PTH) levels, characterized by neuromuscular hyperexcitability, such as limb numbness and tetany. These symptoms severely affect postoperative quality of life and increase the financial burden on patients, especially in cases of permanent hypoPT. Long-term consequences of permanent hypoPT include chronic kidney disease, basal ganglia calcification, and an increased risk of infections, further complicating patient outcomes. Therefore, preventing postoperative hypoPT is an urgent concern for thyroid surgeons.\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e,\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e,\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eThe debate remains on whether more extensive exposure of the PGs during surgery causes more damage or offers better protection. Some studies suggest that active identification and preservation of PGs can reduce the risk of incidental parathyroidectomy and improve long-term gland function.\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e,\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e,\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e Conversely, other reports indicate that excessive manipulation may compromise the gland\u0026rsquo;s vascular supply, leading to transient or permanent dysfunction.\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e,\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e Current literature presents mixed conclusions regarding whether PGs should be actively exposed and fully identified during thyroid surgery. The American Thyroid Association (ATA) statement on postoperative hypoparathyroidism emphasizes the need for standardized surgical approaches to mitigate the risk of hypoPT but does not provide a consensus on the degree of PG exposure required during thyroidectomy.\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003eThis current study is to explore the impact of all 4 PGs exposure on postoperative parathyroid function, focusing on both transient and permanent hypoPT outcomes.\u003c/p\u003e"},{"header":"2. Materials and methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003e2.1. Study design\u003c/h2\u003e\u003cp\u003eThis prospective study analyzed data from patients undergoing TT and CLND (including lateral lymph node dissection, LLND) at the Department of Surgical Oncology, First Affiliated Hospital of Zhejiang University School of Medicine, between January 2020 and June 2024. A total of 211 patients were initially enrolled, all of whom were over 18 years old and operated on by a single surgeon to ensure consistency in surgical technique. A comprehensive thyroid surgery database was established and regularly updated to include surgical details, preoperative and postoperative laboratory tests, and pathological findings, such as intraoperative PG exposure, gland location, evidence of damage or excision, serum calcium levels, and parathyroid hormone (PTH) concentrations.\u003c/p\u003e\u003cp\u003ePatients were divided into two groups according to whether the PGs were systematically exposed: the sufficient exposure group (all 4 PGs exposed) and the insufficient exposure group (fewer than 4 glands exposed). The primary outcomes assessed were hypoPT, categorized as transient or permanent (with a 6-month cutoff), intraoperative parathyroid autotransplantation, and incidental parathyroidectomy (defined as parathyroid tissue identified in routine pathology reports without prior autotransplantation). HypoPT was further classified as biochemical hypoPT (PTH\u0026thinsp;\u0026lt;\u0026thinsp;12 pg/mL accompanied by new-onset hypocalcemia, defined as serum calcium\u0026thinsp;\u0026lt;\u0026thinsp;2.11 mmol/L) or clinical hypoPT (biochemical hypoPT with associated symptoms and/or signs of hypocalcemia).\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eExclusion criteria included a history of thyroid surgery, preoperative thyroid or parathyroid dysfunction, distant metastasis, and incomplete follow-up data. After applying these criteria, 133 patients were included in the final analysis, allowing for a focused evaluation of the relationship between PG exposure and postoperative outcomes.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\u003ch2\u003e2.2. Surgical Technique\u003c/h2\u003e\u003cp\u003eThyroidectomies were performed using the capsular dissection technique. This method involves careful dissection of the soft tissue from the thyroid capsule to preserve the PGs in situ after retraction of the fascia and muscles and elevation of the thyroid\u0026rsquo;s upper and lower poles. Special attention was given to identifying PGs located on or adjacent to the thyroid capsule, particularly near the Zuckerkandl tubercle and the recurrent laryngeal nerve.\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e Once identified, the PGs were meticulously dissected away from the thyroid while preserving their vascular supply as much as possible. Each operation aimed to expose all 4 PGs. Thyroidectomy specimens were carefully examined to identify PGs that were either adherent to or embedded within the thyroid tissue. Similarly, the thyroid bed was inspected for PGs that were completely devascularized or appeared discolored. As described, any devascularized or discolored glands, as well as inadvertently excised parathyroid tissue, were autotransplanted into the ipsilateral sternocleidomastoid muscle.\u003csup\u003e\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e,\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e All autotransplanted PGs were confirmed intraoperatively by frozen section analysis of a representative portion of the excised tissue.\u003c/p\u003e\u003cp\u003eCentral neck dissection (level VI) was performed en bloc, extending from the hyoid bone to the innominate vein and laterally to the carotid sheaths, including prelaryngeal, pretracheal, and bilateral paratracheal nodes. Lateral neck dissection (levels II\u0026ndash;Vb) involved systematic removal of fibrofatty tissue within anatomical compartments, preserving the sternocleidomastoid muscle, internal jugular vein, and spinal accessory nerve. Dissection proceeded from level IIa superiorly to level Vb inferiorly, guided by preoperative imaging and intraoperative findings.\u003csup\u003e\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e,\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e Each nodal basin was submitted separately for pathological evaluation.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\u003ch2\u003e2.3. Data Collection\u003c/h2\u003e\u003cp\u003eCollected data included patient demographics (gender, age, medical history), preoperative and postoperative laboratory values (PTH, serum calcium, phosphorus, magnesium, and potassium levels), and surgical details (extent of surgery\u0026mdash;number of PGs exposed intraoperatively, whether CLND or LLND was performed, and whether parathyroid autotransplantation was conducted). Clinical follow-up data were gathered through outpatient visits and telephone consultations, with a minimum follow-up duration of six months for all patients. Patients were considered lost to follow-up if three telephone attempts at different times were unsuccessful.\u003c/p\u003e\u003cp\u003eThe presence of incidental parathyroidectomy was initially identified by reviewing postoperative pathology reports and was further corroborated through cross-referencing with surgical records, intraoperative frozen section analyses, and final pathology evaluations. This multilayered verification aimed to enhance the accuracy of incidental parathyroidectomy detection and minimize reporting errors.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e\u003ch2\u003e2.4. Statistical Analysis\u003c/h2\u003e\u003cp\u003eData were analyzed using SPSS version 27.0. Descriptive statistics, including counts and percentages, were employed to summarize patient characteristics and surgical outcomes. Continuous variables were compared using independent samples t-tests, while categorical variables were analyzed with chi-square tests in univariate analyses. A two-sided significance threshold was set at 0.05 for all statistical tests. All the figures in this article were drawn using Python 3.10.13.\u003c/p\u003e\u003c/div\u003e"},{"header":"3. Results","content":"\u003cp\u003e\u003cstrong\u003e3.1. Baseline Characteristics of the Patients Enrolled\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe baseline characteristics and relevant laboratory test results of the enrolled patients are summarized in Table 1. A total of 133 patients undergoing total thyroidectomy were included in the final analysis. All patients were newly diagnosed, over 18 years of age, and had confirmed malignant tumors via postoperative pathological examination. All patients underwent lymph node dissection. The mean age was 45.4 \u0026plusmn; 11.2 years, with a predominance of female patients (90/133, 67.7%).\u003c/p\u003e\n\u003cp\u003ePatients were stratified into two groups: the sufficient exposure group (all 4 PGs exposed intraoperatively) and the insufficient exposure group (fewer than 4 glands exposed). No significant differences were observed between the two groups concerning age, gender, tumor multifocality, bilaterality, lymph node dissection extent, capsule invasion, extrathyroidal extension, TNM stage, or history of radioactive iodine treatment (P \u0026gt; 0.05).\u003c/p\u003e\n\u003cp\u003eTable 1. Baseline characteristics of patients enrolled.\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"552\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 86px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariables\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eClassification\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAll cases\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;(N =133, %)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 220px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSufficient exposure\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 47px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eP\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eYes (N=73, %)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo (N=60, %)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eTotal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e133(100)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e73(100)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e60(100)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eGender\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e43(32.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e24(32.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e19(31.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\n \u003cp\u003e0.882\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eFemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e90(67.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e49(67.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e41(68.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eAge\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e＜55y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e99(74.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e57(78.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e42(70)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\n \u003cp\u003e0.288\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026ge;55y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e34(25.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e16(21.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e18(30)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eNo. of parathyroids exposure\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e11(8.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e0(0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e11(18.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e49(36.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e0(0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e49(81.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e73(54.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e73(100)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e0(0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eMultifocality\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e83(62.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e46(63)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e37(61.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\n \u003cp\u003e0.873\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e50(37.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e27(37)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e23(38.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eBilaterality\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e75(56.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e43(58.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e32(53.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\n \u003cp\u003e0.519\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e58(43.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e30(41.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e28(46.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eLymph node dissection\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eCLND\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e104(78.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e56(76.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e48(80)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\n \u003cp\u003e0.648\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eCLND+LLND\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e29(21.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e17(23.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e12(20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eCapsule invasion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e96(72.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e52(71.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e44(73.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\n \u003cp\u003e0.788\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e37(27.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e21(28.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e16(26.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003egETE\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e15(11.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e9(12.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e6(10)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\n \u003cp\u003e0.673\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e118(88.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e64(87.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e54(90)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eT stage\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eT1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e101(75.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e57(78.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e44(73.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\n \u003cp\u003e0.267\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eT2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e8(6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e6(8.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e2(3.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eT3+T4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e24(18)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e10(13.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e14(23.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eN stage\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eN0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e56(42.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e32(43.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e24(40)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\n \u003cp\u003e0.410\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eN1a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e50(37.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e24(32.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e26(43.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003eN1b\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e27(20.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e17(23.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 116px;\"\u003e\n \u003cp\u003e10(16.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 47px;\"\u003e\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eAbbreviation: CLND, central lymph node dissection; LLND, lateral lymph node dissection; gETE, gross extrathyroidal extension; NA, not available\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.2. Parathyroid Function in Both Groups\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAmong the 133 patients, the sufficient exposure group demonstrated a transient biochemical hypoPT rate of 15.1% (n=11/73) compared to 16.7% (n=10/60) in the insufficient exposure group (P=0.801). Similarly, clinical manifestations of transient hypoPT were observed in 9.6% (n=7/73) of the sufficient exposure group versus 11.7% (n=7/60) of the insufficient exposure group (P=0.698). Regarding permanent hypoparathyroidism, the insufficient exposure group showed a 3.3% incidence rate (n= 2/60) for biochemical hypoparathyroidism, while no cases (0%) were identified in the sufficient exposure group (P=0.202). Neither group reported any cases of clinically apparent permanent hypoPT (Table 2).\u003c/p\u003e\n\u003cp\u003eTable 2. Incidence of postoperative complications according to parathyroid gland sufficient exposure.\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"551\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 98px;\"\u003e\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 143px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eComplications\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 234px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSufficient exposure\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eP\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eYes (N=73, %)\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo (N=60, %) \u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"5\" valign=\"top\" style=\"width: 98px;\"\u003e\n \u003cp\u003eTransient changes\u003c/p\u003e\n \u003cp\u003e(\u0026lt;6months)\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\u0026nbsp;\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003eBiochemical hypoPT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e11(15.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e10(16.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e0.801\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003eClinical hypoPT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e7(9.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e7(11.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.698\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003eHypocalcemia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e22(30.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e21(35)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.551\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003ePTH level(\u0026lt;12pg/ml)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e39(53.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e28(46.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.438\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003eNumbness/Tetany\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e13(17.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e10(16.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.862\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"5\" valign=\"top\" style=\"width: 98px;\"\u003e\n \u003cp\u003ePermanent changes\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;(\u0026ge;6 months)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003eBiochemical hypoPT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e0(0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e2(3.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.202\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003eClinical hypoPT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e0(0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e0(0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003eHypocalcemia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e2(2.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e5(8.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.243\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003ePTH level(\u0026lt;12ng/ml)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e2(2.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e2(3.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e1.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003eNumbness/Tetany\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e1(1.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e2(3.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.589\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eAbbreviations: hypoPT, hypoparathyroidism; PTH, parathyroid hormone; NA, not available\u003c/p\u003e\n\u003cp\u003eFollow-up analyses of PTH and serum calcium levels showed no significant differences between the two groups at 1 day, 1 month, and 3 months postoperatively. However, at 6 months post-surgery, PTH levels were significantly higher in the sufficient exposure group (33.22 \u0026plusmn; 16.48 pg/ml vs. 26.48 \u0026plusmn; 10.94 pg/ml, P = 0.048) (Figure 1).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.3. Parathyroid Autotransplantation in Both Groups\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIntraoperative parathyroid autotransplantation was performed in 24 patients (18.0%). Of these, 19 cases occurred in the sufficient exposure group, while only 5 cases were reported in the insufficient exposure group. The sufficient exposure group, which showed a significantly higher rate of autotransplantation (26.0% vs. 8.3%, P = 0.008), was associated with more timely intraoperative identification of compromised PGs. However, parathyroid autotransplantation was found significantly associated with a higher incidence of clinical symptoms within 6 months (37.5% vs. 12.8%, P = 0.007) and transient clinical hypoPT specifically (25.0% vs. 7.3%, P = 0.021) (Table 3), but no significant differences were observed in PTH and serum calcium levels between patients who underwent autotransplantation and those who did not within the first six months postoperatively (P \u0026gt; 0.05).\u003c/p\u003e\n\u003cp\u003eTable 3. Incidence of postoperative outcomes according to number of parathyroid autotransplantation.\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"551\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 98px;\"\u003e\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 143px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eComplications\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 234px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eParathyroid autotransplantation\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eP\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eYes (N=24, %)\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo (N=109, %) \u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"5\" valign=\"top\" style=\"width: 98px;\"\u003e\n \u003cp\u003eTransient changes\u003c/p\u003e\n \u003cp\u003e(\u0026lt;6months)\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\u0026nbsp;\u0026nbsp;\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003eBiochemical hypoPT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e2(8.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e19(17.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e0.364\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003eClinical hypoPT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e6(25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e8(7.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.021\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003eHypocalcemia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e4(16.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e39(35.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.070\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003ePTH level(\u0026lt;12pg/ml)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e13(54.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e56(51.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.804\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003eNumbness/Tetany\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e9(37.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e14(12.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.007\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"5\" valign=\"top\" style=\"width: 98px;\"\u003e\n \u003cp\u003ePermanent\u003c/p\u003e\n \u003cp\u003echanges\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;(\u0026ge;6 months)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003eBiochemical hypoPT1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e0(0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e2(1.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e1.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003eClinical hypoPT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e0(0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e0(0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003eHypocalcemia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e3(12.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e4(3.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.111\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003ePTH level(\u0026lt;12ng/ml)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e2(8.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e2(1.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.149\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003eNumbness/Tetany\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e1(4.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 117px;\"\u003e\n \u003cp\u003e2(1.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.452\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eAbbreviations: hypoPT, hypoparathyroidism; PTH, parathyroid hormone; NA, not available\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.4. Rate of Incidental Parathyroidectomy in Both Groups\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eChi-square analysis indicated no significant difference in the occurrence of incidental parathyroidectomy between the sufficient and insufficient exposure groups (17.8% vs. 18.3%, P = 0.938). The overall incidence of incidental parathyroidectomy was 17.8%(n=13/73). The accuracy of visual identification for PGs during thyroidectomy was 82.2%, as determined by postoperative pathological confirmation.\u003c/p\u003e"},{"header":"4. Discussion","content":"\u003cp\u003eIn this prospective study including 133 patients who underwent TT and CLND, exposure of all 4 PGs neither increased transient\u0026nbsp;hypoPT (15.1 % vs. 16.7 %; P = 0.801) nor permanent hypoPT (0 % vs. 3.3 %; P=0.202). More importantly, the fully exposed cohort exhibited a higher mean serum PTH concentration at six months (33.2 \u0026plusmn; 16.5 vs. 26.5 \u0026plusmn; 10.9 pg/mL; \u003cem\u003eP\u003c/em\u003e = 0.048), underscoring that deliberate visualization safeguards immediate endocrine integrity and accelerates long-term functional recovery.\u003c/p\u003e\n\u003cp\u003eTo our knowledge, this is the first report confined to a TT + CLND population, a setting intrinsically more demanding than the mixed or pure thyroidectomy cohorts previously studied.\u0026nbsp;The safety signal we observed echoes findings from Mehta et al. (transient hypocalcemia 18.0 % with \u0026ge;2 glands identified vs. 19.2 % with \u0026le;1 gland; P = 0.84) and Sitges-Serra et al. (14.3 % vs. 15.8 %; P = 0.78), whereas Riordan et al. linked identification of \u0026ge;3 glands to a 70 % higher odds of biochemical hypocalcemia (OR 1.7, 95 % CI 1.1\u0026ndash;2.9). That series, however, excluded CLND, thereby examining a less complex surgical situation. Our data therefore extend earlier work by demonstrating that, even under the heightened ischemic risk imposed by CLND, visualization does not confer harm and may in fact be protective.\u003c/p\u003e\n\u003cp\u003eSystematic exposure inevitably heightened intra-operative recognition of devascularized glands, yielding a higher autotransplantation rate in our cohort (26.0 % vs. 8.3 %). Although graft recipients experienced more transient symptomatic hypocalcemia, this trade-off mirrors prior endoscopic TT + CLND data\u0026mdash;Cheng \u003cem\u003eet al.\u003c/em\u003e reported a similar early dip in PTH yet no disadvantage beyond the first postoperative week.\u003csup\u003e19\u003c/sup\u003e By 1 month, re-implanted tissue begins secreting hormone; experimental perfusion studies show functional recovery is largely complete within 4\u0026ndash;8 weeks, with serum PTH rising in parallel.\u0026nbsp;\u003csup\u003e20\u003c/sup\u003e Consistent with these kinetics, a population study of 342 thyroidectomies found that autotransplantation shortened the median time to biochemical normalization from 32 days to 7 days and eliminated permanent hypoPT.\u003csup\u003e21\u003c/sup\u003e By contrast, two recent single-center analyses failed to demonstrate a reduction in permanent disease; their cohorts transplanted predominantly \u0026ldquo;doubtful\u0026rdquo; tissue after prolonged manipulation, a practice associated with lower graft viability.\u003csup\u003e22,23\u003c/sup\u003e Collectively, prompt reimplantation of PGs effectively speed endocrine recovery and may avert permanent hypoPT.\u003c/p\u003e\n\u003cp\u003eThis study has several limitations. As a single-center study, the findings may not be generalizable to broader clinical settings. In addition, the relatively small number of patients with permanent hypoPT limited the ability to draw definitive conclusions regarding long-term outcomes. Larger, multicenter studies with extended follow-up are needed to validate these results and to further investigate factors influencing postoperative parathyroid function.\u003c/p\u003e"},{"header":"5. Conclusion","content":"\u003cp\u003eIn patients undergoing TT+CLND for thyroid cancer, sufficient exposure of PGs is beneficial to the recovery of postoperative PTH level, and does not increase the incidence of temporary hypoPT. While our findings support the safety of sufficient PG exposure in CLND-containing procedures, future studies should aim to establish the optimal balance between adequate visualization for gland preservation and excessive dissection that might compromise vascular integrity.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthical approval\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was conducted following the ethical standards of the 1964 Declaration of Helsinki and approved by the Ethics Review Committee of the First Affiliated Hospital of Zhejiang University, Ethical approval number: [2025B] IIT Ethics Approval No.0386.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical trial number\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to Publish declaration\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Disclosure Statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eXinguang Jin, Zehang Xu, Liping Wen, Xianmeng Chen, Weibin Wang, Shitu Chen, Haijie Huang, Lisong Teng, and Xiongfei Yu declare no conflicts of interest and no competing financial interests exist.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eInformed consent\u0026nbsp;was obtained from all participants of the study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability Statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research was supported by Zhejiang Medical Association Clinical Medicine Research Special Fund Project (No.2022ZYC-A200)\u003cstrong\u003e.\u003c/strong\u003e\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eOrloff, L. A. \u003cem\u003eet al.\u003c/em\u003e American Thyroid Association Statement on Postoperative Hypoparathyroidism: Diagnosis, Prevention, and Management in Adults. \u003cem\u003eThyroid\u003c/em\u003e \u003cstrong\u003e28\u003c/strong\u003e, 830\u0026ndash;841 (2018).\u003c/li\u003e\n\u003cli\u003ePonce De Le\u0026oacute;n-Ballesteros, G. \u003cem\u003eet al.\u003c/em\u003e Hypoparathyroidism After Total Thyroidectomy: Importance of the Intraoperative Management of the Parathyroid Glands. \u003cem\u003eWorld J. Surg.\u003c/em\u003e \u003cstrong\u003e43\u003c/strong\u003e, 1728\u0026ndash;1735 (2019).\u003c/li\u003e\n\u003cli\u003ePattou, F. \u003cem\u003eet al.\u003c/em\u003e Hypocalcemia following Thyroid Surgery: Incidence and Prediction of Outcome. \u003cem\u003eWorld J. Surg.\u003c/em\u003e \u003cstrong\u003e22\u003c/strong\u003e, 718\u0026ndash;724 (1998).\u003c/li\u003e\n\u003cli\u003eRafferty, M. A. \u003cem\u003eet al.\u003c/em\u003e Completion Thyroidectomy Versus Total Thyroidectomy: Is There a Difference in Complication Rates? An Analysis of 350 Patients. \u003cem\u003eJ. Am. Coll. Surg.\u003c/em\u003e \u003cstrong\u003e205\u003c/strong\u003e, 602\u0026ndash;607 (2007).\u003c/li\u003e\n\u003cli\u003eSitges-Serra, A. Etiology and Diagnosis of Permanent Hypoparathyroidism after Total Thyroidectomy. \u003cem\u003eJ. Clin. Med.\u003c/em\u003e \u003cstrong\u003e10\u003c/strong\u003e, 543 (2021).\u003c/li\u003e\n\u003cli\u003eHundahl, S. A. \u003cem\u003eet al.\u003c/em\u003e Initial results from a prospective cohort study of 5583 cases of thyroid carcinoma treated in the United States during 1996: An American College of Surgeons Commission on Cancer patient care evaluation study. \u003cem\u003eCancer\u003c/em\u003e \u003cstrong\u003e89\u003c/strong\u003e, 202\u0026ndash;217 (2000).\u003c/li\u003e\n\u003cli\u003eSu, A. \u003cem\u003eet al.\u003c/em\u003e Risk factors of hypoparathyroidism following total thyroidectomy with central lymph node dissection. \u003cem\u003eMedicine (Baltimore)\u003c/em\u003e \u003cstrong\u003e96\u003c/strong\u003e, e8162 (2017).\u003c/li\u003e\n\u003cli\u003eThomusch, O. \u003cem\u003eet al.\u003c/em\u003e Multivariate Analysis of Risk Factors for Postoperative Complications in Benign Goiter Surgery: Prospective Multicenter Study in Germany. \u003cem\u003eWorld J. Surg.\u003c/em\u003e \u003cstrong\u003e24\u003c/strong\u003e, 1335\u0026ndash;1341 (2000).\u003c/li\u003e\n\u003cli\u003eWinged, D. J., Friesen, S. R., Ilkqoulos, J. I., Pierce, G. E. \u0026amp; Thomas, J. H. Post-Thyroidectomy tiypocalcemia. \u003cem\u003eAm. J. Surg.\u003c/em\u003e\u003c/li\u003e\n\u003cli\u003eDolores, S. Hypoparathyroidism. \u003cem\u003eN. Engl. J. Med.\u003c/em\u003e (2008).\u003c/li\u003e\n\u003cli\u003eWang, X. \u003cem\u003eet al.\u003c/em\u003e Postoperative hypoparathyroidism after thyroid operation and exploration of permanent hypoparathyroidism evaluation. \u003cem\u003eFront. Endocrinol.\u003c/em\u003e \u003cstrong\u003e14\u003c/strong\u003e, 1182062 (2023).\u003c/li\u003e\n\u003cli\u003eThomusch, O. \u003cem\u003eet al.\u003c/em\u003e The impact of surgical technique on postoperative hypoparathyroidism in bilateral thyroid surgery: A multivariate analysis of 5846 consecutive patients. \u003cem\u003eSurgery\u003c/em\u003e \u003cstrong\u003e133\u003c/strong\u003e, 180\u0026ndash;185 (2003).\u003c/li\u003e\n\u003cli\u003eRiordan, F., Murphy, M. S., Feeley, L. \u0026amp; Sheahan, P. Association between number of parathyroid glands identified during total thyroidectomy and functional parathyroid preservation. \u003cem\u003eLangenbecks Arch. Surg.\u003c/em\u003e \u003cstrong\u003e407\u003c/strong\u003e, 297\u0026ndash;303 (2022).\u003c/li\u003e\n\u003cli\u003eSheahan, P., Mehanna, R., Basheeth, N. \u0026amp; Murphy, M. S. Is systematic identification of all four parathyroid glands necessary during total thyroidectomy?: A prospective study: Identifying Parathyroid During Thyroidectomy. \u003cem\u003eThe Laryngoscope\u003c/em\u003e \u003cstrong\u003e123\u003c/strong\u003e, 2324\u0026ndash;2328 (2013).\u003c/li\u003e\n\u003cli\u003eLorente-Poch, L., Sancho, J. J., Ruiz, S. \u0026amp; Sitges-Serra, A. Importance of \u003cem\u003ein situ\u003c/em\u003e preservation of parathyroid glands during total thyroidectomy. \u003cem\u003eBr. J. Surg.\u003c/em\u003e \u003cstrong\u003e102\u003c/strong\u003e, 359\u0026ndash;367 (2015).\u003c/li\u003e\n\u003cli\u003eMehta, S., Dhiwakar, M. \u0026amp; Swaminathan, K. Outcomes of parathyroid gland identification and autotransplantation during total thyroidectomy. \u003cem\u003eEur. Arch. Otorhinolaryngol.\u003c/em\u003e \u003cstrong\u003e277\u003c/strong\u003e, 2319\u0026ndash;2324 (2020).\u003c/li\u003e\n\u003cli\u003eHaugen, B. R. \u003cem\u003eet al.\u003c/em\u003e 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. \u003cem\u003eThyroid\u003c/em\u003e \u003cstrong\u003e26\u003c/strong\u003e, 1\u0026ndash;133 (2016).\u003c/li\u003e\n\u003cli\u003eRandolph, G. W. \u003cem\u003eet al.\u003c/em\u003e The Prognostic Significance of Nodal Metastases from Papillary Thyroid Carcinoma Can Be Stratified Based on the Size and Number of Metastatic Lymph Nodes, as Well as the Presence of Extranodal Extension. \u003cem\u003eThyroid\u003c/em\u003e \u003cstrong\u003e22\u003c/strong\u003e, 1144\u0026ndash;1152 (2012).\u003c/li\u003e\n\u003cli\u003eCheng, X., Li, Y. \u0026amp; Chen, L. Efficacy of parathyroid autotransplantation in endoscopic total thyroidectomy with CLND. \u003cem\u003eFront. Endocrinol.\u003c/em\u003e \u003cstrong\u003e14\u003c/strong\u003e, 1193851 (2023).\u003c/li\u003e\n\u003cli\u003eGe, G. \u003cem\u003eet al.\u003c/em\u003e Effectiveness of parathyroid autotransplantation during total thyroidectomy and functional recovery post-operation: A retrospective study. \u003cem\u003eEur. J. Surg. Oncol.\u003c/em\u003e \u003cstrong\u003e51\u003c/strong\u003e, 110007 (2025).\u003c/li\u003e\n\u003cli\u003eYazıcıoğlu, M. \u0026Ouml;., Yılmaz, A., Koca\u0026ouml;z, S., \u0026Ouml;z\u0026ccedil;ağlayan, R. \u0026amp; Parlak, \u0026Ouml;. Risks and prediction of postoperative hypoparathyroidism due to thyroid surgery. \u003cem\u003eSci. Rep.\u003c/em\u003e \u003cstrong\u003e11\u003c/strong\u003e, 11876 (2021).\u003c/li\u003e\n\u003cli\u003eKasmirski, J. A. \u003cem\u003eet al.\u003c/em\u003e Does Parathyroid Autotransplantation Prevent Hypoparathyroidism after Thyroid Surgery? \u003cem\u003eAnn. Surg.\u003c/em\u003e (2025) doi:10.1097/SLA.0000000000006631.\u003c/li\u003e\n\u003cli\u003eKoimtzis, G., Stefanopoulos, L., Geropoulos, G. \u0026amp; Papavramidis, T. The outcomes of parathyroid gland autotransplantation during thyroid surgery: a systematic review, meta-analysis and trial sequential analysis. \u003cem\u003eEndocrine\u003c/em\u003e \u003cstrong\u003e87\u003c/strong\u003e, 27\u0026ndash;38 (2024).\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"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":"bmc-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bsur","sideBox":"Learn more about [BMC Surgery](http://bmcsurg.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bsur/default.aspx","title":"BMC Surgery","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Hypoparathyroidism, Parathyroid Gland Preservation, Total Thyroidectomy, Parathyroid Autotransplantation","lastPublishedDoi":"10.21203/rs.3.rs-7446726/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7446726/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground:\u003c/h2\u003e\u003cp\u003eHypoparathyroidism (HypoPT) is the most common complication after total thyroidectomy (TT) and central lymph node dissection (CLND) for thyroid carcinoma. However, there\u0026rsquo;s still no effective surgical strategy to prevent its incidence. This study evaluated the impact of sufficient intraoperative exposure of the parathyroid glands (PG) on postoperative parathyroid function, the rate of parathyroid autotransplantation, and incidental parathyroidectomy.\u003c/p\u003e\u003ch2\u003eMethods:\u003c/h2\u003e\u003cp\u003eProspective data from 133 consecutive patients who underwent TT and CLND by a single surgeon at the First Affiliated Hospital of Zhejiang University School of Medicine were systematically collected. All patients were categorized into sufficient exposure (exposed) group and insufficient exposure (control) group based on whether all 4 PGs were identified during surgery. PG exposure and autotransplantation were recorded intraoperatively, while incidental parathyroidectomy was determined via routine pathology reports. Postoperative parathyroid hormone (PTH) levels, serum calcium levels, and hypocalcemia-related symptoms (limb numbness/tetany) were monitored for at least six months. Continuous variables were compared using independent samples t-test for normally distributed data., while categorical variables were analyzed using Pearson\u0026rsquo;s chi-square test. A two-sided P-value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e\u003ch2\u003eResults:\u003c/h2\u003e\u003cp\u003eNo patients in the sufficient exposure group developed permanent hypoPT, while 2 patients in the insufficient exposure group exhibited biochemical hypoPT. Mean PTH levels were significantly higher in the sufficient exposure group (33.22\u0026thinsp;\u0026plusmn;\u0026thinsp;16.48 pg/ml vs. 26.48\u0026thinsp;\u0026plusmn;\u0026thinsp;10.94 pg/ml, P\u0026thinsp;=\u0026thinsp;0.048) within six months. Parathyroid autotransplantation was more frequent in the sufficient exposure group (26.0% vs. 8.3%, P\u0026thinsp;=\u0026thinsp;0.008). For transient hypoPT, incidental parathyroidectomy or clinical symptoms, there was no significant difference between groups (P\u0026thinsp;\u0026gt;\u0026thinsp;0.05).\u003c/p\u003e\u003ch2\u003eConclusion:\u003c/h2\u003e\u003cp\u003eSufficient exposure of the PGs during surgery can potentially protect parathyroid function in terms of PTH level without increasing transient hypoPT, indicating PG sufficient exposure is a practical way to protect parathyroid function.\u003c/p\u003e","manuscriptTitle":"Sufficient Intraoperative Exposure of Parathyroid Glands Protects Long‑Term Parathyroid Function After Total Thyroidectomy plus Central Lymph Node Dissection for Papillary Thyroid Carcinoma","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-22 06:24:54","doi":"10.21203/rs.3.rs-7446726/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-02-24T09:25:54+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-24T05:28:08+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"117089940234619211337014862007904728560","date":"2026-02-18T07:17:27+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-03T15:59:50+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"268477588444100926368507435962782138083","date":"2025-09-23T19:15:57+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-09-18T06:32:48+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-09-03T19:00:44+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-08-30T13:10:14+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-08-30T13:09:11+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Surgery","date":"2025-08-24T14:14:13+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bsur","sideBox":"Learn more about [BMC Surgery](http://bmcsurg.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bsur/default.aspx","title":"BMC Surgery","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"3791bb06-e965-4244-b19a-e16e07100b01","owner":[],"postedDate":"September 22nd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[],"tags":[],"updatedAt":"2026-05-15T07:26:05+00:00","versionOfRecord":[],"versionCreatedAt":"2025-09-22 06:24:54","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7446726","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7446726","identity":"rs-7446726","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}