{"paper_id":"6159f40a-9395-482b-8588-0e1cface8a7e","body_text":"Overuse of Follow-up Chest Computed Tomography in Patients With Incidentally Identified Nodules Suspicious for Lung Cancer | 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 Overuse of Follow-up Chest Computed Tomography in Patients With Incidentally Identified Nodules Suspicious for Lung Cancer Ran Guo, Yang Zhang, Zelin Ma, Chaoqiang Deng, Fangqiu Fu, Hong Hu, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-259864/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 08 Jul, 2021 Read the published version in Journal of Cancer Research and Clinical Oncology → Version 1 posted 4 You are reading this latest preprint version Abstract Purpose : Regardless of professional societies agreed that CT screening inconsistent with recommendation leads to radiation-related cancer and unexpected cost, many patients undergo unnecessary chest CT before treatment. The goal of this study was to assess the overuse of Chest CT in different type of patients. Methods: Data on 1853 patients who underwent pulmonary resection from May 2019 to May 2020 were retrospectively analyzed. Data collected include age, sex, follow-up time, density and size of nodules and frequency of undergoing Chest CT. Pearson χ2 test and logistic regression were conducted to compare the receipt of CT screening. Results : Among 1853 patients in the study, 689 (37.2%) had overused Chest CT during follow-up of the lung cancer. This rate was 16.2% among patients with solid nodules, 57.5% among patients with pure ground glass opacity (pGGO), and 41.4% among patients with mixed ground glass opacity (mGGO) (P<.001). 50.7% in the “age ≤40” group, 39.8% in the “41≤age ≤50” group, 38.7% in the “51≤age ≤60” group, 32.3% in the “61≤age ≤70” group, 27.8% in the “>70” group underwent unnecessary CT (P<.001). Female get more unnecessary CT than male (40.6% vs 32.8%, P <.001). Factors associated with a greater likelihood of Chest CT is the density of nodules (odds ratios [ORs] of 0.53 for mGGO; 0.15 for solid nodule, P<.0001, vs patients with pGGO). Conclusion : roughly 37% patients with pulmonary nodules received Chest CT too frequently despite national recommendations against the practice. Closer adherence to clinical guidelines is likely to result in more cost-effective care. Cancer Biology Oncology Non–small cell lung cancer lung cancer screening Safety Chest CT Figures Figure 1 Introduction Lung cancer is the leading cause of cancer death worldwide, with an estimated 1.6 million deaths annually. 1 Since a high range of lung cancer occurs and develops without any symptom until end-stage, screening becomes significant method of spotting lung cancer. As the US National Lung Screening Trial (NLST), Nederlands–Leuvens Longkanker Screenings Onderzoek (NELSON) and other trial revealed that Computed Tomography (CT) can produce more effect compared with X-ray, Chest CT becomes the first choice of lung cancer screening. 2-5 However, CT is not a perfect choice for lung cancer screening. According to John Brodersen, 49% of detected cancers by Low-dose CT (LDCT) may be overdiagnosed, 6-7 and researchers also mentioned that risk of radiation-induced cancers can be a potentially harmful effect of Chest CT which is cumulative over a lifetime. 2,8-11 . Another concern is the cost-effectiveness of the Chest CT. The NLST results suggested that screening with low-dose CT cost $100,000 per QALY gained, but study of William C. Black showed that screening conducted outside the trial may be costlier if patients’ counseling and follow-up are properly accounted for the price. 2,12 The cost could become more considerable if the number of unnecessary CT scans increase, making a heavy burden for patients and economy of healthcare. To minimize the risk of radiation and unnecessary cost, multiple specialty societies have issued recommendations against Chest CT for patients with suspicious pulmonary nodules. 13-15 Although specific recommendations differ somewhat, all societies agreed that CT screening is not an examination which can be experienced without limitation. But even with these numerous guidelines and recommendations, overuse of Chest CT is routinely performed in patients with nodule suspicious for pulmonary tumor. The goal of this study was to assess the use of Chest CT in patients with pulmonary nodules, and identify the demographic and clinical factors associated with receipt of Chest CT. Materials And Methods Patients and samples From May 2019 to May 2020, we consecutively procured data of lung cancer patients who underwent pulmonary resection in the Department of Thoracic Surgery, Fudan University Shanghai Cancer Center, Shanghai, China. The frequency of CT screening is collected by telephone follow-up and checking medical history. Subjects eligible for this study had to meet the following criteria: complete follow-up history and clinical data. Patients who received neoadjuvant chemotherapy were excluded from the study because of inconsistencies of the reason they get Chest CT. Patients with a recurrent lung cancer, with multiple concurrent cancers, and with former other malignancies were also excluded from the study. Patients who underwent Chest CT because of symptoms related to lung cancer were excluded since the NCCN guideline cannot apply to them. This research was approved by the Institutional Review Board of the Fudan University Shanghai Cancer Center, Shanghai, China. Written informed consent was obtained from all patients. As different patients need different strategies of CT screening, we used the guideline of NCCN which gave the advice for patients who incidentally found nodules suspicious for lung cancer, 13 and then grouped them into two groups: abiding by the guideline or not. Statistical Analysis All the statistical analyses were performed in the SPSS for Windows (Version 16.0, Chicago, IL). We assessed the baseline characteristics of patients included in our sample, grouped them by following the guideline or not. Age, sex, density and size of nodules are modeled as categorical variables. Variables were reported as counts and percentages, and groups were compared using chi-square tests for significance. We used the Pearson χ2 test to compare the lung cancer detection rate. Finally, we performed a multivariable logistic regression for the likelihood of overusing Chest CT for staging. P-values were two-tailed for all the tests. Statistical significance was set as p<0.05. Results Among 2667 patients with nodules suspicious for lung cancer, a total of 1853 patients met inclusion criteria (Figure 1). All patients were Chinese. Baseline demographic and clinical characteristics of the cohort are summarized in Table 1. Table.1 Baseline Demographic and Clinical Characteristics variable Overall Cohort n (%) Not abiding by the guildline n (%) abiding by the guildline n (%) P value * Total, n 1853 (100) 689 (37.2) 1164(62.8) Sex <0.001 Male 816(44.0) 268 (32.8) 548 (67.2) Female 1037 (56.0) 421 (40.6) 618 (59.4) Age, y <0.001 ≤40 209 (11.3) 106 (50.7) 103 (49,3) 41～50 324 (17.5) 129 (39.8) 195 (60.2) 51～60 561 (30.3) 217 (38.7) 344 (61.3) 61～70 572 (30.9) 185 (32.3) 387 (67.7) >70 187 (10.1) 52 (27.8) 135 (72.2) Nodule density <0.001 pGGO 478 (25.8) 275 (57.5） 203(42.5) mGGO 759 (40.9) 314 (41.4) 445 (58.6) Solid nodule 616(33.2) 100 (16.2) 516 (83.8) Abbreviations: pGGO: pure ground glass opacity. mGGO: mixed ground glass opacity. *Bold indicates statistically significant P values (P<0.05) Overall, during the 12-months study period, around 37.2% of our patients underwent excessive CT. The proportion of females was 56.0%. 40.6% of them ignored the recommendation, while this rate changed to 32.8% among males. The percentage of patients ≤40 years, 41 to 50 years, 51 to 60 years, 61 to 70 years and >70 years were11.3%, 17.5%, 30.3%, 30.9% and 10.1%, and 50.7%, 39.8%, 38.7%, 32,3%, 27.8% of them received unnecessary examination. As for density of nodules, 25.8% found pure ground glass opacity(pGGO), 40.9% found mixed ground glass opacity (mGGO), and 32.2% found solid nodules during their screening. 57.5%, 41.4%, and 16.2% of them did not abide by the guideline of NCCN. Table 2. Required following-up times for different density of nodule variable Overall Cohort n (%) Not abiding by the guildline n (%) abiding by the guildline n (%) P value * pGGO <0.001 0 167 (34.9) 93 (55.7) 74 (44.3) 1 243 (50.8) 125 (51.4) 118 (48.6) 2 48 (10.0) 39 (81.3) 9 (18.8) 3 11 (2.3) 10 (90.9) 1 (9.1) >3 9 (1.9) 8(88.9) 1 (10.1) mGGO <0.001 0 295 (37.3) 144 (50.9) 139 (49.1) 1 274 (33.9) 62(24.1) 195 (75.9) 2 84 (10.9) 49 (59.0) 34 (41.0) 3 71 (9.4) 29 (40.8) 42 (59.2) >3 65 (8.6) 30 (46.2) 35 (53.8) Solid nodule <0.001 0 440 (56.6) 39 (11.2) 310(88.8) 1 182 (22.1) 16 (11.8) 120(88.2) >1 152 (21.3) 45 (34.4) 86 (65.6) Abbreviations: pGGO: pure ground glass opacity. mGGO: mixed ground glass opacity. *Bold indicates statistically significant P values (P<0.05) Since different density of nodules need different screening strategies, we grouped patients by their density of nodules and assessed how many patients who need different follow-up time were inconsistent with NCCN (Table 2). As a result, for patients with pGGO, 55.7% of patients who need 0 follow-up violated the recommendation, and this rate ranged into 51.4%, 81.3%, 90.9%, 88.9% for who need 1, 2, 3 and more than 3 follow-ups. As for patients with mGGO, 50.9%, 24.1%, 59.0%, 40.8%, 46.2% patients who need 0, 1, 2, 3 and more than 3 follow-ups were not adhere to the guideline, and 11.2%, 11.8%, 34.4% patients with solid nodules who need 0, 1, 2 follow-ups underwent unnecessary Chest CT for screening. In univariable analysis, factors associated with greater use of CT included younger age (odds ratios [ORs] of 0.64 for 41–50 years, P=.014; 0.62 for 51–60 years, P=.003; 0.47 for 61–70 years, P<.001; and 0.37 for ≥71 years, P<.0001; vs ≤40 years), female sex (OR, 1.40; P <.001) and lower nodule density(ORs of 0.52 for mGGO, P<.001; 0.14 for solid nodule, P<.001)(Table 3). In terms of the following-up time, patients tended to abide by the guideline when the first follow-up was recommended (ORs of 0.84 for patients with pure GGO, P=.040; 0.30 for mGGO, P<.001). Correlations among patients’ unnecessary CT scan with clinical features were further evaluated by multivariable analysis using logistic regression analysis (Table 4). The result suggested that density of the nodules were independent predictors of overusing Chest CT (ORs of 0.53 for mGGO, P<.0001; 0.15 for solid nodule, P<.0001, vs patients with pGGO). Table 3. Univariable analysis of Associations with Chest CT Characteristic OR P value * Age, y ≤40 Ref 41～50 0.64 (0.45 – 0.91) 0.014 51～60 0.62 (0.45 – 0.85) 0.003 61～70 0.47 (0.34 – 0.64) <0.001 ≥71 0.37 (0.25 – 0.57) <0.001 Sex Male Ref Female 1.40 (1.15 - 1.70) <0.001 Nodule density pGGO Ref mGGO 0.52 (0.41 – 0.65) <0.001 Solid nodule 0.14 (0.11 – 0.19) <0.001 Required following-up times for different density of nodule pGGO 0 Ref 1 0.84 (0.39 – 0.91) 0.40 2 3.45 (2.27 – 8.63) 0.002 3 7.96 (1.82 – 21.82) 0.050 >3 6..37(0.78-52.04) 0.084 mGGO 0 Ref 1 0.30 (0.21 – 0.44) <0.001 2 1.39 (0.85 – 2.28) 0.192 3 0.67 (0.39 – 1.13) 0.132 >3 0.83 (0.48 – 1.42) 0.492 Solid nodule 0 Ref 1 1.12 (0.61 – 2.07) 0.70 >1 4.16 (2.55 – 6.80) <0.001 Abbreviations: OR: odds ratio. pGGO: pure ground glass opacity. mGGO: mixed ground glass opacity. *Bold indicates statistically significant P values (P<0.05) Table 4. Multivariable analysis of Associations with Chest CT Characteristic OR P value * Age, y 41～50 0.83 (0.57 – 1.20) 0.320 51～60 0.93 (0.66 – 1.31) 0.658 61～70 0.83 (0.59 – 1.19) 0.318 ≥71 0.80 (0.50 – 1.26) 0.328 Sex Female 0.99 (0.81 - 1.22) 0.941 Nodule density mGGO 0.53 (0.42 – 0.68) <0.001 Solid nodule 0.15 (0.11 – 0.20) <0.001 Abbreviations: OR: odds ratio. mGGO: mixed ground glass opacity. *Bold indicates statistically significant P values (P<0.05) Discussion Despite the mention of risk about overuse of Chest CT by specialty societies, patients were still willing to get the examination as many as possible. In this retrospective cohort study, we found that almost 1 in 3 patients received unnecessary lung cancer screening, and the rate dramatically varied by different characteristics. Previous study suggested the disadvantage of unnecessary Chest CT, and there were studies about overuse of Chest CT in patients with breast cancer or studies about lung cancer screening inconsistent with USPSTF, 16-18 but to our knowledge, this is the first study to assess the overuse of Chest CT during follow-up after finding nodules suspicious for lung cancer. Our study finally showed that overuse of CT is likely to happen in patients with less density, and patients with pGGO most tend to undergo CT scan which is inconsistent with recommendation. As a fact, there is no perfect method to distinguish malignant and benign GGO with accurate certainty. A period of follow-up may be helpful for diagnosis, but the interval of follow-up can be longer than 1 year. Lee et al reported that pure GGO lesions ≤10 mm have a volume-doubling time of more than 400 days, and a study from Japan also suggested that the optimal observation period for patients with multiple GGOs is 36 months. 19-20 NCCN guidelines recommended that both pGGO and mGGO <6 mm do not require any follow up and that pure GGOs ≥6 mm should be followed every 2 years, for up to 5 years. 13 But since a percentage of GGNs disappear spontaneously in short term, 21 some medical workers routinely ask patients to get examination again in 3 months after they found pulmonary opacities to check if the GGO is only an inflammation, leading to a potential risk of overusing CT scan. Another study of Lee et al suggested that 2 of 90 GGNs (2.2%) followed up for more than 4 years showed significant growth after 4 years, and whether patients need Chest CT after 5 years follow-up still remains a problem. 22 These can be reasons for undergoing Chest CT without complying with the recommendation. Female and younger patients also showed higher rate of inconsistence with NCCN, but this factor may not be the true influencer of unnecessary Chest CT as percentage of GGO is also higher among these groups in our study. 30.8% of females found pGGO during their Chest CT screening, whereas only 14.8% of males found pGGO nodules. This result is in line with those reported by Huang et al. 23 Their study revealed that pGGO is associated with females, and although there is not significance difference, younger age patients get more pGGO in the research. Given that our analysis relied on data of Fudan University Shanghai Cancer Center and telephone following-up, there are some incumbent limitations to consider. Prior studies have already revealed significant geographic variation about screening and therapy protocol in clinical practice. 24-25 A certain level of recalling bias should be acknowledged, and furthermore, our conclusions only apply to the population analyzed – patients who got pulmonary resection in Fudan University Shanghai Cancer Center. We also excluded patients who had history of other malignant tumors or neoadjuvant therapy, which can lead to selection bias. These patients usually have more advanced disease, and were more likely to get examination for accurate diagnosis, but the purpose of CT for them could be evaluating the therapeutic effect instead of screening, so their examination history shouldn’t be judged by the guideline. It would be interest to evaluate the variations among different area and hospitals, and further research in this aspect is warranted. Conclusion This retrospective analysis of the data suggests overuse of unnecessary Chest CT in patients with lung nodules suspicious for lung cancer, and this rate vary by radiologic density of the nodules. This dissimilarity may stem from clinical uncertainty, general lack of familiarity with national recommendations and patients’ anxious about tumor. Efforts to disseminate evidence-based best practices and adherence to the guidelines will not only spare patients’ unnecessary radiation, also curb excessive spending. Declarations Funding : This work was supported by the National Natural Science Foundation of China (81930073), Shanghai Science and Technology Innovation Action Project (20JC1417200), Shanghai Municipal Science and Technology Major Project (2017SHZDZX01, VBH1323001/026), Shanghai Municipal Key Clinical Specialty Project (SHSLCZDZK02104), and Pilot Project of Fudan University (IDF159045). Conflicts of interest/Competing interests : We declare that there is no professional or other personal interest of any nature or kind in any product Availability of data and material: all data and material is applicable. Code availability: we used SPSS to analyze our data, and the software is applicable. Ethics approval : This research was approved by the Institutional Review Board of the Fudan University Shanghai Cancer Center, Shanghai, China. Consent to participate : Written informed consent was obtained from all patients. Consent for publication : Written informed consent for publication was obtained from all patients. Acknowledgements This work was supported by the National Natural Science Foundation of China (81930073), Shanghai Science and Technology Innovation Action Project (20JC1417200), Shanghai Municipal Science and Technology Major Project (2017SHZDZX01, VBH1323001/026), Shanghai Municipal Key Clinical Specialty Project (SHSLCZDZK02104), and Pilot Project of Fudan University (IDF159045) . References International Agency for Research on Cancer, World Health Organization. Lung cancer. In: GLOBOCAN 2012: estimated cancer incidence, mortality and prevalence worldwide in 2012. Lyon, France: International Agency for Research on Cancer, World Health Organization; 2013 National Lung Screening Trial Research Team, Aberle DR, Adams AM, et al. Reduced lung-cancer mortality with low-dose computed tomographic screening. N Engl J Med. 2011;365(5):395-409. doi:10.1056/NEJMoa1102873 Yousaf-Khan U, van der Aalst C, de Jong PA, et al. 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Overuse of Diagnostic Brain Imaging Among Patients With Stage IA Non-Small Cell Lung Cancer. J Natl Compr Canc Netw. 2020;18(5):547-554. doi:10.6004/jnccn.2019.7384 Cite Share Download PDF Status: Published Journal Publication published 08 Jul, 2021 Read the published version in Journal of Cancer Research and Clinical Oncology → Version 1 posted Editorial decision: Major revisions needed 16 Apr, 2021 Reviewers invited by journal 10 Mar, 2021 Editor assigned by journal 22 Feb, 2021 First submitted to journal 19 Feb, 2021 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {\"props\":{\"pageProps\":{\"initialData\":{\"identity\":\"rs-259864\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":false,\"archivedVersions\":[],\"articleType\":\"Research Article\",\"associatedPublications\":[],\"authors\":[{\"id\":16180065,\"identity\":\"35deab2e-f56c-4909-a7bc-f124b467ae2f\",\"order_by\":0,\"name\":\"Ran Guo\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Fudan University Shanghai Cancer Center\",\"correspondingAuthor\":false,\"submittingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Ran\",\"middleName\":\"\",\"lastName\":\"Guo\",\"suffix\":\"\"},{\"id\":16180066,\"identity\":\"35ef04cf-d1a6-4a80-aee7-ac3339223184\",\"order_by\":1,\"name\":\"Yang 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Center\",\"correspondingAuthor\":false,\"submittingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Chaoqiang\",\"middleName\":\"\",\"lastName\":\"Deng\",\"suffix\":\"\"},{\"id\":16180069,\"identity\":\"20190fdb-35de-49d2-ad8f-bfa1b4c1e493\",\"order_by\":4,\"name\":\"Fangqiu Fu\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Fudan University Shanghai Cancer Center\",\"correspondingAuthor\":false,\"submittingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Fangqiu\",\"middleName\":\"\",\"lastName\":\"Fu\",\"suffix\":\"\"},{\"id\":16180070,\"identity\":\"1159ebd3-717d-4b39-919c-002c461cac67\",\"order_by\":5,\"name\":\"Hong Hu\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Fudan University Shanghai Cancer Center\",\"correspondingAuthor\":false,\"submittingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Hong\",\"middleName\":\"\",\"lastName\":\"Hu\",\"suffix\":\"\"},{\"id\":16180071,\"identity\":\"e720b9cb-e8c7-42c8-a902-7476d4109944\",\"order_by\":6,\"name\":\"Yihua Sun\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Fudan University Shanghai Cancer Center\",\"correspondingAuthor\":false,\"submittingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Yihua\",\"middleName\":\"\",\"lastName\":\"Sun\",\"suffix\":\"\"},{\"id\":16180072,\"identity\":\"34de22bf-022d-4329-93ad-4bb88b9e841c\",\"order_by\":7,\"name\":\"Haiquan Chen\",\"email\":\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAu0lEQVRIiWNgGAWjYBACAwYGNiAlIcfAwEOaFgtjkrVUJDYQrcWcPfnZg487JNI3HD978MEHBjs53QYCWix7npkbzjwjkbvhTF6y4QyGZGOzA4QcdiOHTZq3DajlQI6ZNA/DgcRtRGn52yaRbnD+DSlaGNskEoAMYrWceWYm2dsmYTjzxhtjwxkGxPjlePIziZ9tdfJ853MMH3yosJMjqIWBIQFCKYBVGhBUjqRFvoEo1aNgFIyCUTASAQCwLEFVnx8p0wAAAABJRU5ErkJggg==\",\"orcid\":\"https://orcid.org/0000-0002-1305-971X\",\"institution\":\"Fudan University Shanghai Cancer Center\",\"correspondingAuthor\":true,\"submittingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Haiquan\",\"middleName\":\"\",\"lastName\":\"Chen\",\"suffix\":\"\"}],\"badges\":[],\"createdAt\":\"2021-02-20 18:02:07\",\"currentVersionCode\":1,\"declarations\":\"\",\"doi\":\"10.21203/rs.3.rs-259864/v1\",\"doiUrl\":\"https://doi.org/10.21203/rs.3.rs-259864/v1\",\"draftVersion\":[],\"editorialEvents\":[{\"content\":\"https://doi.org/10.1007/s00432-021-03692-6\",\"type\":\"published\",\"date\":\"2021-07-08T15:00:39+00:00\"}],\"editorialNote\":\"\",\"failedWorkflow\":false,\"files\":[{\"id\":7034488,\"identity\":\"21e0c4de-1c37-417f-b28c-93923ed2563e\",\"added_by\":\"auto\",\"created_at\":\"2021-03-16 22:24:42\",\"extension\":\"png\",\"order_by\":1,\"title\":\"Figure 1\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":119295,\"visible\":true,\"origin\":\"\",\"legend\":\"Study Cohort\",\"description\":\"\",\"filename\":\"Fig01.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-259864/v1/ebc7edabaffa4c51a0e531cd.png\"},{\"id\":13680810,\"identity\":\"3dd8075d-d570-4908-af48-af5a4388293a\",\"added_by\":\"auto\",\"created_at\":\"2021-09-17 11:48:37\",\"extension\":\"pdf\",\"order_by\":0,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"manuscript-pdf\",\"size\":371363,\"visible\":true,\"origin\":\"\",\"legend\":\"\",\"description\":\"\",\"filename\":\"manuscript.pdf\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-259864/v1/32656f01-cf7f-4a6a-8181-68b6b3386c82.pdf\"}],\"financialInterests\":\"\",\"formattedTitle\":\"\\u003cp\\u003eOveruse of Follow-up Chest Computed Tomography in Patients With Incidentally Identified Nodules Suspicious for Lung Cancer\\u003c/p\\u003e\",\"fulltext\":[{\"header\":\"Introduction\",\"content\":\"\\u003cp\\u003eLung cancer is the leading cause of\\u0026nbsp;cancer death worldwide, with an estimated 1.6 million deaths annually. \\u003csup\\u003e1\\u003c/sup\\u003e Since a high range of lung cancer occurs and develops without any symptom until end-stage, screening becomes significant method of spotting lung cancer. As the US National Lung Screening Trial\\u0026nbsp;(NLST), Nederlands\\u0026ndash;Leuvens Longkanker Screenings Onderzoek (NELSON) and other trial revealed that Computed Tomography (CT) can produce more effect compared with X-ray, Chest CT becomes the first choice of lung cancer screening. \\u003csup\\u003e2-5\\u003c/sup\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eHowever, CT is not a perfect choice for lung cancer screening. According to John Brodersen, 49% of detected cancers by Low-dose CT (LDCT) may be overdiagnosed, \\u003csup\\u003e6-7\\u003c/sup\\u003eand researchers also mentioned that risk of radiation-induced cancers can be a potentially harmful effect of Chest CT which is cumulative over a lifetime. \\u003csup\\u003e2,8-11\\u003c/sup\\u003e. Another concern is the cost-effectiveness of the Chest CT. The NLST results suggested that screening with low-dose CT cost $100,000 per QALY gained, but study of William C. Black showed that screening conducted outside the trial may be costlier if patients\\u0026rsquo; counseling and follow-up are properly accounted for the price. \\u003csup\\u003e2,12\\u003c/sup\\u003e The cost could become more considerable if the number of unnecessary CT scans increase, making a heavy burden for patients and economy of healthcare.\\u003c/p\\u003e\\n\\u003cp\\u003eTo minimize the risk of radiation and unnecessary cost, multiple specialty societies have issued recommendations against\\u0026nbsp;Chest CT for patients with suspicious pulmonary nodules. \\u003csup\\u003e13-15\\u003c/sup\\u003e Although specific recommendations differ somewhat, all societies agreed that CT screening is not an examination which can be experienced without limitation. But even with these numerous guidelines and recommendations, overuse of Chest CT is routinely performed in patients with nodule suspicious for pulmonary tumor. The goal of this study was to assess the use of Chest CT in patients with pulmonary nodules, and identify the demographic and clinical factors associated with receipt of Chest CT.\\u003c/p\\u003e\"},{\"header\":\"Materials And Methods\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003ePatients and samples\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eFrom May 2019 to May 2020, we consecutively procured data of lung cancer patients who underwent pulmonary resection in the Department of Thoracic Surgery, Fudan University Shanghai Cancer Center, Shanghai, China. The frequency of CT screening is collected by telephone follow-up and checking medical history. Subjects eligible for this study had to meet the following criteria: complete follow-up history and clinical data. Patients who received neoadjuvant chemotherapy were excluded from the study because of inconsistencies of the reason they get Chest CT. Patients with a recurrent lung cancer, with multiple concurrent cancers, and with former other malignancies were also excluded from the study. Patients who underwent Chest CT because of symptoms related to lung cancer were excluded since the NCCN guideline cannot apply to them. This research was approved by the Institutional Review Board of the Fudan University Shanghai Cancer Center, Shanghai, China. Written informed consent was obtained from all patients.\\u003c/p\\u003e\\n\\u003cp\\u003eAs different patients need different strategies of CT screening, we used the guideline of NCCN which gave the advice for patients who incidentally found nodules suspicious for lung cancer, \\u003csup\\u003e13\\u003c/sup\\u003e and then grouped them into two groups: abiding by the guideline or not.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eStatistical Analysis\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003e\\u0026nbsp;All the statistical analyses were performed in the SPSS for Windows (Version 16.0, Chicago, IL). We assessed the baseline characteristics of patients included in our sample, grouped them by following the guideline or not. Age, sex, density and size of nodules are modeled as categorical variables. Variables were reported as counts and percentages, and groups were compared using chi-square tests for significance. We used the Pearson \\u0026chi;2\\u0026nbsp;test to compare the lung cancer detection rate. Finally, we performed a multivariable logistic regression for the likelihood of overusing Chest CT for staging. P-values were two-tailed for all the tests. Statistical significance was set as\\u0026nbsp;p\\u0026lt;0.05.\\u003c/p\\u003e\"},{\"header\":\"Results\",\"content\":\"\\u003cp\\u003eAmong 2667 patients with nodules suspicious for lung cancer, a total of 1853 patients met inclusion criteria (Figure 1). All patients were Chinese. Baseline demographic and clinical characteristics of the cohort are summarized in Table 1.\\u003c/p\\u003e\\n\\u003ctable border=\\\"1\\\"\\u003e\\n\\u003ctbody\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"5\\\" width=\\\"100%\\\"\\u003e\\n\\u003cp\\u003eTable.1 Baseline Demographic and Clinical Characteristics\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003evariable\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003eOverall Cohort\\u003c/p\\u003e\\n\\u003cp\\u003en (%)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003eNot abiding by the guildline\\u003c/p\\u003e\\n\\u003cp\\u003en (%)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003eabiding by the guildline\\u003c/p\\u003e\\n\\u003cp\\u003en (%)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003eP value\\u003csup\\u003e*\\u003c/sup\\u003e\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003eTotal, n\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e1853 (100)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e689 (37.2)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e1164(62.8)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"4\\\" width=\\\"80%\\\"\\u003e\\n\\u003cp\\u003eSex\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026lt;0.001\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; Male\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e816(44.0)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e268 (32.8)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e548 (67.2)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; Female\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e1037 (56.0)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e421 (40.6)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e618 (59.4)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"4\\\" width=\\\"80%\\\"\\u003e\\n\\u003cp\\u003eAge, y\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026lt;0.001\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; \\u0026le;40\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e209 (11.3)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e106 (50.7)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e103 (49,3)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; 41～50\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e324 (17.5)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e129 (39.8)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e195 (60.2)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; 51～60\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e561 (30.3)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e217 (38.7)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e344 (61.3)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; 61～70\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e572 (30.9)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e185 (32.3)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e387 (67.7)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; \\u0026gt;70\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e187 (10.1)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e52 (27.8)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e135 (72.2)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"4\\\" width=\\\"80%\\\"\\u003e\\n\\u003cp\\u003eNodule density\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026lt;0.001\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; pGGO\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e478 (25.8)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e275 (57.5）\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e203(42.5)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; mGGO\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e759 (40.9)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e314 (41.4)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e445 (58.6)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; Solid nodule\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e616(33.2)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e100 (16.2)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e516 (83.8)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003c/tbody\\u003e\\n\\u003c/table\\u003e\\n\\u003cp\\u003eAbbreviations:\\u003c/p\\u003e\\n\\u003cp\\u003epGGO: pure ground glass opacity.\\u003c/p\\u003e\\n\\u003cp\\u003emGGO: mixed ground glass opacity.\\u003c/p\\u003e\\n\\u003cp\\u003e*Bold indicates statistically significant P values (P\\u0026lt;0.05)\\u003c/p\\u003e\\n\\u003cp\\u003eOverall, during the 12-months study period, around 37.2% of our patients underwent excessive CT. The proportion of females was 56.0%. 40.6% of them ignored the recommendation, while this rate changed to 32.8% among males. The percentage of patients \\u0026le;40\\u0026nbsp;years, 41 to 50\\u0026nbsp;years, 51 to 60\\u0026nbsp;years, 61 to 70\\u0026nbsp;years and \\u0026gt;70\\u0026nbsp;years\\u0026nbsp;were11.3%, 17.5%, 30.3%, 30.9% and 10.1%, and 50.7%, 39.8%, 38.7%, 32,3%, 27.8% of them received unnecessary examination.\\u003c/p\\u003e\\n\\u003cp\\u003eAs for density of nodules, 25.8% found pure ground glass opacity(pGGO), 40.9% found mixed ground glass opacity (mGGO), and 32.2% found solid nodules during their screening. 57.5%, 41.4%, and 16.2% of them did not abide by the guideline of NCCN.\\u003c/p\\u003e\\n\\u003ctable border=\\\"1\\\"\\u003e\\n\\u003ctbody\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"5\\\" width=\\\"100%\\\"\\u003e\\n\\u003cp\\u003eTable 2. Required following-up times for different density of nodule\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003evariable\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003eOverall Cohort\\u003c/p\\u003e\\n\\u003cp\\u003en (%)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003eNot abiding by the guildline\\u003c/p\\u003e\\n\\u003cp\\u003en (%)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003eabiding by the guildline\\u003c/p\\u003e\\n\\u003cp\\u003en (%)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003eP value\\u003csup\\u003e*\\u003c/sup\\u003e\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"4\\\" width=\\\"80%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;pGGO\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026lt;0.001\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e167 (34.9)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e93 (55.7)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e74 (44.3)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 1\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e243 (50.8)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e125 (51.4)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e118 (48.6)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 2\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e48 (10.0)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e39 (81.3)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e9 (18.8)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 3\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e11 (2.3)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e10 (90.9)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e1 (9.1)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; \\u0026gt;3\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e9 (1.9)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e8(88.9)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e1 (10.1)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"4\\\" width=\\\"80%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; mGGO\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026lt;0.001\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e295 (37.3)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e144 (50.9)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e139 (49.1)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 1\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e274 (33.9)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e62(24.1)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e195 (75.9)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 2\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e84 (10.9)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e49 (59.0)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e34 (41.0)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 3\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e71 (9.4)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e29 (40.8)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e42 (59.2)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; \\u0026gt;3\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e65 (8.6)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e30 (46.2)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e35 (53.8)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"4\\\" width=\\\"80%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; Solid nodule\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026lt;0.001\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e440 (56.6)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e39 (11.2)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e310(88.8)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 1\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e182 (22.1)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e16 (11.8)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e120(88.2)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"22%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; \\u0026gt;1\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e152 (21.3)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e45 (34.4)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e86 (65.6)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"19%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003c/tbody\\u003e\\n\\u003c/table\\u003e\\n\\u003cp\\u003eAbbreviations:\\u003c/p\\u003e\\n\\u003cp\\u003epGGO: pure ground glass opacity.\\u003c/p\\u003e\\n\\u003cp\\u003emGGO: mixed ground glass opacity.\\u003c/p\\u003e\\n\\u003cp\\u003e*Bold indicates statistically significant P values (P\\u0026lt;0.05)\\u003c/p\\u003e\\n\\u003cp\\u003eSince different density of nodules need different screening strategies, we grouped patients by their density of nodules and assessed how many patients who need different follow-up time were inconsistent with NCCN (Table 2). As a result, for patients with pGGO, 55.7% of patients who need 0 follow-up violated the recommendation, and this rate ranged into 51.4%, 81.3%, 90.9%, 88.9% for who need 1, 2, 3 and more than 3 follow-ups. As for patients with mGGO, 50.9%, 24.1%, 59.0%, 40.8%, 46.2% patients who need 0, 1, 2, 3 and more than 3 follow-ups were not adhere to the guideline, and 11.2%, 11.8%, 34.4% patients with solid nodules who need 0, 1, 2 follow-ups underwent unnecessary Chest CT for screening.\\u003c/p\\u003e\\n\\u003cp\\u003eIn univariable analysis, factors associated with greater use of CT included younger age (odds ratios [ORs] of 0.64 for 41\\u0026ndash;50 years,\\u0026nbsp;P=.014; 0.62 for 51\\u0026ndash;60 years,\\u0026nbsp;P=.003; 0.47 for 61\\u0026ndash;70 years,\\u0026nbsp;P\\u0026lt;.001; and 0.37 for \\u0026ge;71 years,\\u0026nbsp;P\\u0026lt;.0001; vs \\u0026le;40 years), female sex (OR, 1.40;\\u0026nbsp;\\u003cem\\u003eP\\u003c/em\\u003e\\u0026lt;.001) and lower nodule density(ORs of 0.52 for mGGO, P\\u0026lt;.001; 0.14 for solid nodule, P\\u0026lt;.001)(Table 3). In terms of the following-up time, patients tended to abide by the guideline when the first follow-up was recommended (ORs of 0.84 for patients with pure GGO, P=.040; 0.30 for mGGO, P\\u0026lt;.001).\\u003c/p\\u003e\\n\\u003cp\\u003eCorrelations among patients\\u0026rsquo; unnecessary CT scan with clinical features were further evaluated by multivariable analysis using logistic regression analysis (Table 4). The result suggested that density of the nodules were independent predictors of overusing Chest CT (ORs of 0.53 for mGGO, P\\u0026lt;.0001; 0.15 for solid nodule, P\\u0026lt;.0001, vs patients with pGGO).\\u003c/p\\u003e\\n\\u003ctable border=\\\"1\\\"\\u003e\\n\\u003ctbody\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"3\\\" width=\\\"553\\\"\\u003e\\n\\u003cp\\u003eTable 3. Univariable analysis of Associations with Chest CT\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003eCharacteristic\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003eOR\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003eP value\\u003csup\\u003e*\\u003c/sup\\u003e\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"3\\\" width=\\\"553\\\"\\u003e\\n\\u003cp\\u003eAge, y\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; \\u0026le;40\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003eRef\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; 41～50\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.64 (0.45 \\u0026ndash; 0.91)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.014\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; 51～60\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.62 (0.45 \\u0026ndash; 0.85)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.003\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; 61～70\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.47 (0.34 \\u0026ndash; 0.64)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026lt;0.001\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; \\u0026ge;71\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.37 (0.25 \\u0026ndash; 0.57)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026lt;0.001\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"3\\\" width=\\\"553\\\"\\u003e\\n\\u003cp\\u003eSex\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; Male\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003eRef\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; Female\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e1.40 (1.15 - 1.70)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026lt;0.001\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"3\\\" width=\\\"553\\\"\\u003e\\n\\u003cp\\u003eNodule density\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; pGGO\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003eRef\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; mGGO\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.52 (0.41 \\u0026ndash; 0.65)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026lt;0.001\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; Solid nodule\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.14 (0.11 \\u0026ndash; 0.19)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026lt;0.001\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"3\\\" width=\\\"553\\\"\\u003e\\n\\u003cp\\u003eRequired following-up times for different density of nodule\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"3\\\" width=\\\"553\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; pGGO\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003eRef\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 1\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.84 (0.39 \\u0026ndash; 0.91)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.40\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 2\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e3.45 (2.27 \\u0026ndash; 8.63)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.002\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 3\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e7.96 (1.82 \\u0026ndash; 21.82)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.050\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; \\u0026gt;3\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e6..37(0.78-52.04)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.084\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"3\\\" width=\\\"553\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; mGGO\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003eRef\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 1\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.30 (0.21 \\u0026ndash; 0.44)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026lt;0.001\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 2\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e1.39 (0.85 \\u0026ndash; 2.28)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.192\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 3\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.67 (0.39 \\u0026ndash; 1.13)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.132\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; \\u0026gt;3\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.83 (0.48 \\u0026ndash; 1.42)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.492\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"3\\\" width=\\\"553\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; Solid nodule\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003eRef\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 1\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e1.12 (0.61 \\u0026ndash; 2.07)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.70\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; \\u0026gt;1\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e4.16 (2.55 \\u0026ndash; 6.80)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026lt;0.001\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003c/tbody\\u003e\\n\\u003c/table\\u003e\\n\\u003cp\\u003eAbbreviations:\\u003c/p\\u003e\\n\\u003cp\\u003eOR: odds ratio.\\u003c/p\\u003e\\n\\u003cp\\u003epGGO: pure ground glass opacity.\\u003c/p\\u003e\\n\\u003cp\\u003emGGO: mixed ground glass opacity.\\u003c/p\\u003e\\n\\u003cp\\u003e*Bold indicates statistically significant P values (P\\u0026lt;0.05)\\u003c/p\\u003e\\n\\u003ctable border=\\\"1\\\"\\u003e\\n\\u003ctbody\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"3\\\" width=\\\"553\\\"\\u003e\\n\\u003cp\\u003eTable 4. Multivariable analysis of Associations with Chest CT\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003eCharacteristic\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003eOR\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003eP value\\u003csup\\u003e*\\u003c/sup\\u003e\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"3\\\" width=\\\"553\\\"\\u003e\\n\\u003cp\\u003eAge, y\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"3\\\" width=\\\"553\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; 41～50\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.83 (0.57 \\u0026ndash; 1.20)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.320\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; 51～60\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.93 (0.66 \\u0026ndash; 1.31)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.658\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; 61～70\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.83 (0.59 \\u0026ndash; 1.19)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.318\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; \\u0026ge;71\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.80 (0.50 \\u0026ndash; 1.26)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.328\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"3\\\" width=\\\"553\\\"\\u003e\\n\\u003cp\\u003eSex\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; Female\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.99 (0.81 - 1.22)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.941\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"3\\\" width=\\\"553\\\"\\u003e\\n\\u003cp\\u003eNodule density\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; mGGO\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.53 (0.42 \\u0026ndash; 0.68)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026lt;0.001\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; Solid nodule\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e0.15 (0.11 \\u0026ndash; 0.20)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"184\\\"\\u003e\\n\\u003cp\\u003e\\u0026lt;0.001\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003c/tbody\\u003e\\n\\u003c/table\\u003e\\n\\u003cp\\u003eAbbreviations:\\u003c/p\\u003e\\n\\u003cp\\u003eOR: odds ratio.\\u003c/p\\u003e\\n\\u003cp\\u003emGGO: mixed ground glass opacity.\\u003c/p\\u003e\\n\\u003cp\\u003e*Bold indicates statistically significant P values (P\\u0026lt;0.05)\\u003c/p\\u003e\"},{\"header\":\"Discussion\",\"content\":\"\\u003cp\\u003eDespite the mention of risk about overuse of Chest CT by specialty societies, patients were still willing to get the examination as many as possible. In this retrospective cohort study, we found that almost 1 in 3 patients received unnecessary lung cancer screening, and the rate dramatically varied by different characteristics. Previous study suggested the disadvantage of unnecessary Chest CT, and there were studies about overuse of Chest CT in patients with breast cancer or studies about lung cancer screening inconsistent with USPSTF, \\u003csup\\u003e16-18\\u003c/sup\\u003e but to our knowledge, this is the first study to assess the overuse of Chest CT during follow-up after finding nodules suspicious for lung cancer.\\u003c/p\\u003e\\n\\u003cp\\u003eOur study finally showed that overuse of CT is likely to happen in patients with less density, and patients with pGGO most tend to undergo CT scan which is inconsistent with recommendation. As a fact, there is no perfect method to distinguish malignant and benign GGO with accurate certainty. A period of follow-up may be helpful for diagnosis, but the interval of follow-up can be longer than 1 year. Lee et al reported that pure GGO lesions \\u0026le;10 mm have a volume-doubling time of more than 400 days, and a study from Japan also suggested that the optimal observation period for patients with multiple GGOs is 36 months. \\u003csup\\u003e19-20\\u003c/sup\\u003e NCCN guidelines recommended that both pGGO and mGGO \\u0026lt;6 mm do not require any follow up and that pure GGOs \\u0026ge;6 mm should be followed every 2 years, for up to 5 years. \\u003csup\\u003e13\\u003c/sup\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eBut since a percentage of GGNs disappear spontaneously in short term, \\u003csup\\u003e21 \\u003c/sup\\u003esome medical workers routinely ask patients to get examination again in 3 months after they found pulmonary opacities to check if the GGO is only an inflammation, leading to a potential risk of overusing CT scan. Another study of Lee et al suggested that 2 of 90 GGNs (2.2%) followed up for more than 4 years showed significant growth after 4 years, and whether patients need Chest CT after 5 years follow-up still remains a problem. \\u003csup\\u003e22\\u003c/sup\\u003e These can be reasons for undergoing Chest CT without complying with the recommendation.\\u003c/p\\u003e\\n\\u003cp\\u003eFemale and younger patients also showed higher rate of inconsistence with NCCN, but this factor may not be the true influencer of unnecessary Chest CT as percentage of GGO is also higher among these groups in our study. 30.8% of females found pGGO during their Chest CT screening, whereas only 14.8% of males found pGGO nodules. This result is in line with those reported by Huang et al. \\u003csup\\u003e23\\u003c/sup\\u003e Their study revealed that pGGO is associated with females, and although there is not significance difference, younger age patients get more pGGO in the research.\\u003c/p\\u003e\\n\\u003cp\\u003eGiven that our analysis relied on data of Fudan University Shanghai Cancer Center and telephone following-up, there are some incumbent limitations to consider. Prior studies have already revealed significant geographic variation about screening and therapy protocol in clinical practice. \\u003csup\\u003e24-25\\u003c/sup\\u003e A certain level of recalling bias should be acknowledged, and furthermore, our conclusions only apply to the population analyzed \\u0026ndash; patients who got pulmonary resection in Fudan University Shanghai Cancer Center. We also excluded patients who had history of other malignant tumors or neoadjuvant therapy, which can lead to selection bias. These patients usually have more advanced disease, and were more likely to get examination for accurate diagnosis, but the purpose of CT for them could be evaluating the therapeutic effect instead of screening, so their examination history shouldn\\u0026rsquo;t be judged by the guideline. It would be interest to evaluate the variations among different area and hospitals, and further research in this aspect is warranted.\\u003c/p\\u003e\"},{\"header\":\"Conclusion\",\"content\":\"\\u003cp\\u003eThis retrospective analysis of the data suggests overuse of unnecessary Chest CT in patients with lung nodules suspicious for lung cancer, and this rate vary by radiologic density of the nodules. This dissimilarity may stem from clinical uncertainty, general lack of familiarity with national recommendations and patients\\u0026rsquo; anxious about tumor. Efforts to disseminate evidence-based best practices and adherence to the guidelines will not only spare patients\\u0026rsquo; unnecessary radiation, also curb excessive spending.\\u003c/p\\u003e\"},{\"header\":\"Declarations\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003eFunding\\u003c/strong\\u003e: This work was supported by the National Natural Science Foundation of China (81930073), Shanghai Science and Technology Innovation Action Project (20JC1417200), Shanghai Municipal Science and Technology Major Project (2017SHZDZX01, VBH1323001/026), Shanghai Municipal Key Clinical Specialty Project (SHSLCZDZK02104), and Pilot Project of Fudan University (IDF159045).\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eConflicts of interest/Competing interests\\u003c/strong\\u003e: We declare that there is no professional or other personal interest of any nature or kind in any product\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAvailability of data and material: \\u003c/strong\\u003eall data and material is applicable.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eCode availability: \\u003c/strong\\u003ewe used SPSS to analyze our data, and the software is applicable.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eEthics approval\\u003c/strong\\u003e: This research was approved by the Institutional Review Board of the Fudan University Shanghai Cancer Center, Shanghai, China.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eConsent to participate\\u003c/strong\\u003e: Written informed consent was obtained from all patients.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eConsent for publication\\u003c/strong\\u003e: \\u0026nbsp;Written informed consent for publication was obtained from all patients.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAcknowledgements\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThis work was supported by the \\u003cem\\u003eNational Natural Science Foundation of China (81930073), Shanghai Science and Technology Innovation Action Project (20JC1417200), Shanghai Municipal Science and Technology Major Project (2017SHZDZX01, VBH1323001/026), Shanghai Municipal Key Clinical Specialty Project (SHSLCZDZK02104), and Pilot Project of Fudan University (IDF159045)\\u003c/em\\u003e.\\u003c/p\\u003e\"},{\"header\":\"References\",\"content\":\"\\u003col\\u003e\\n\\u003cli\\u003eInternational Agency for Research on Cancer, World Health Organization. Lung cancer. In: GLOBOCAN\\u0026nbsp;2012: estimated cancer incidence, mortality and prevalence worldwide in 2012. Lyon, France: International Agency for Research on Cancer, World Health Organization; 2013\\u003c/li\\u003e\\n\\u003cli\\u003eNational Lung Screening Trial Research Team, Aberle DR, Adams AM, et al. Reduced lung-cancer mortality with low-dose computed tomographic screening.\\u0026nbsp;N Engl J Med. 2011;365(5):395-409. doi:10.1056/NEJMoa1102873\\u0026nbsp;\\u003c/li\\u003e\\n\\u003cli\\u003eYousaf-Khan U, van der Aalst C, de Jong PA, et al. Risk stratification based on screening history: the NELSON lung cancer screening study.\\u0026nbsp;Thorax. 2017;72(9):819-824. doi:10.1136/thoraxjnl-2016-209892\\u003c/li\\u003e\\n\\u003cli\\u003ePastorino U, Sverzellati N, Sestini S, et al. Ten-year results of the Multicentric Italian Lung Detection trial demonstrate the safety and efficacy of biennial lung cancer screening.\\u0026nbsp;Eur J Cancer. 2019;118:142-148. doi:10.1016/j.ejca.2019.06.009\\u003c/li\\u003e\\n\\u003cli\\u003ede Koning HJ, van der Aalst CM, de Jong PA, et al. Reduced Lung-Cancer Mortality with Volume CT Screening in a Randomized Trial.\\u0026nbsp;N Engl J Med. 2020;382(6):503-513. doi:10.1056/NEJMoa1911793\\u003c/li\\u003e\\n\\u003cli\\u003evan der Aalst CM, Ten Haaf K, de Koning HJ. Lung cancer screening: latest developments and unanswered questions.\\u0026nbsp;Lancet Respir Med. 2016;4(9):749-761. doi:10.1016/S2213-2600(16)30200-4\\u003c/li\\u003e\\n\\u003cli\\u003eBrodersen J, Voss T, Martiny F, Siersma V, Barratt A, Heleno B. Overdiagnosis of lung cancer with low-dose computed tomography screening: meta-analysis of the randomised clinical trials. Breathe (Sheff). 2020 Mar;16(1):200013. doi: 10.1183/20734735.0013-2020. PMID: 32194774; PMCID: PMC7078745.\\u003c/li\\u003e\\n\\u003cli\\u003eBach PB, Mirkin JN, Oliver TK, et al. Benefits and harms of CT screening for lung cancer: a systematic review [published correction appears in JAMA. 2012 Oct 3;308(13):1324] [published correction appears in JAMA. 2013 Jun 5;309(21):2212].\\u0026nbsp;JAMA. 2012;307(22):2418-2429. doi:10.1001/jama.2012.5521\\u003c/li\\u003e\\n\\u003cli\\u003eRampinelli C, De Marco P, Origgi D, et al. Exposure to low dose computed tomography for lung cancer screening and risk of cancer: secondary analysis of trial data and risk-benefit analysis.\\u0026nbsp;BMJ. 2017;356:j347. Published 2017 Feb 8. doi:10.1136/bmj.j347\\u003c/li\\u003e\\n\\u003cli\\u003eKalra MK, Maher MM, Rizzo S, Kanarek D, Shepard JA. Radiation exposure from chest CT: issues and strategies [published correction appears in J Korean Med Sci. 2004 Jun;19(3):487. Shephard JA [corrected to Shepard JA]].\\u0026nbsp;J Korean Med Sci. 2004;19(2):159-166. doi:10.3346/jkms.2004.19.2.159\\u003c/li\\u003e\\n\\u003cli\\u003eBoard on Radiation Effects Research, Division on Earth and Life Studies, National Research Council of the National Academies.\\u0026nbsp;Health risks from exposure to low levels of ionizing radiation. BEIR VII, Phase 2.\\u0026nbsp;Washington, DC:\\u0026nbsp;National Academies Press;\\u0026nbsp;2005.\\u003c/li\\u003e\\n\\u003cli\\u003eBlack WC, Gareen IF, Soneji SS, et al. Cost-effectiveness of CT screening in the National Lung Screening Trial.\\u0026nbsp;N Engl J Med. 2014;371(19):1793-1802. doi:10.1056/NEJMoa1312547\\u003c/li\\u003e\\n\\u003cli\\u003eEttinger\\u0026nbsp;DS,\\u0026nbsp;Argiris\\u0026nbsp;A,\\u0026nbsp;Bepler\\u0026nbsp;G.\\u0026nbsp;NCCN Clinical Practice Guidelines in Oncology: Non\\u0026ndash;Small Cell Lung Cancer. Version 1.2004. Obtained with permission from NCCN February 2, 2019. To view the most recent version, visit\\u0026nbsp;\\u003ca href=\\\"https://webvpn.fudan.edu.cn/http/77726476706e69737468656265737421ded462b2693f7a57\\\"\\u003eorg\\u003c/a\\u003e.\\u003c/li\\u003e\\n\\u003cli\\u003eKazerooni EA, Armstrong MR, Amorosa JK, et al. ACR CT accreditation program and the lung cancer screening program designation.\\u0026nbsp;J Am Coll Radiol. 2015;12(1):38-42. doi:10.1016/j.jacr.2014.10.002\\u0026nbsp;\\u003c/li\\u003e\\n\\u003cli\\u003eWender R, Fontham ET, Barrera E Jr, et al. American Cancer Society lung cancer screening guidelines.\\u0026nbsp;CA Cancer J Clin. 2013;63(2):107-117. doi:10.3322/caac.21172\\u003c/li\\u003e\\n\\u003cli\\u003eDull B, Linkugel A, Margenthaler JA, Cyr AE. Overuse of Chest CT in Patients With Stage I and II Breast Cancer: An Opportunity to Increase Guidelines Compliance at an NCCN Member Institution.\\u0026nbsp;J Natl Compr Canc Netw. 2017;15(6):783-789. doi:10.6004/jnccn.2017.0104\\u003c/li\\u003e\\n\\u003cli\\u003eRichards TB, Doria-Rose VP, Soman A, et al. Lung Cancer Screening Inconsistent With U.S. Preventive Services Task Force Recommendations.\\u0026nbsp;Am J Prev Med. 2019;56(1):66-73. doi:10.1016/j.amepre.2018.07.030\\u003c/li\\u003e\\n\\u003cli\\u003eFarjah F, Monsell SE, Gould MK, et al. Association of the Intensity of Diagnostic Evaluation With Outcomes in Incidentally Detected Lung Nodules [published online ahead of print, 2021 Jan 19].\\u0026nbsp;JAMA Intern Med. 2021;e208250. doi:10.1001/jamainternmed.2020.8250.\\u003c/li\\u003e\\n\\u003cli\\u003eSato Y, Fujimoto D, Morimoto T, et al. Natural history and clinical characteristics of multiple pulmonary nodules with ground glass opacity.\\u0026nbsp;Respirology. 2017;22(8):1615-1621. doi:10.1111/resp.13089\\u003c/li\\u003e\\n\\u003cli\\u003eOh JY, Kwon SY, Yoon HI, et al. Clinical significance of a solitary ground-glass opacity (GGO) lesion of the lung detected by chest CT.\\u0026nbsp;Lung Cancer. 2007;55(1):67-73. doi:10.1016/j.lungcan.2006.09.009\\u003c/li\\u003e\\n\\u003cli\\u003eLee SW, Leem CS, Kim TJ, et al. The long-term course of ground-glass opacities detected on thin-section computed tomography.\\u0026nbsp;Respir Med. 2013;107(6):904-910. doi:10.1016/j.rmed.2013.02.014\\u003c/li\\u003e\\n\\u003cli\\u003eHuang C, Wang C, Wang Y, et al. The Prognostic Significance of Pure Ground Glass Opacities in Lung Cancer Computed Tomographic Images.\\u0026nbsp;J Cancer. 2019;10(27):6888-6895. Published 2019 Nov 17. doi:10.7150/jca.33132\\u003c/li\\u003e\\n\\u003cli\\u003eBalekian AA, Fisher JM, Gould MK. Brain Imaging for Staging of Patients With Clinical Stage IA Non-small Cell Lung Cancer in the National Lung Screening Trial: Adherence With Recommendations From the Choosing Wisely\\u0026nbsp;Campaign.\\u0026nbsp;Chest. 2016;149(4):943-950. doi:10.1378/chest.15-1140\\u003c/li\\u003e\\n\\u003cli\\u003eMilligan MG, Cronin AM, Colson Y, et al. Overuse of Diagnostic Brain Imaging Among Patients With Stage IA Non-Small Cell Lung Cancer.\\u0026nbsp;J Natl Compr Canc Netw. 2020;18(5):547-554. doi:10.6004/jnccn.2019.7384\\u003c/li\\u003e\\n\\u003c/ol\\u003e\"}],\"fulltextSource\":\"\",\"fullText\":\"\",\"funders\":[],\"hasAdminPriorityOnWorkflow\":false,\"hasManuscriptDocX\":true,\"hasOptedInToPreprint\":true,\"hasPassedJournalQc\":\"\",\"hasAnyPriority\":false,\"hideJournal\":false,\"highlight\":\"\",\"institution\":\"\",\"isAcceptedByJournal\":true,\"isAuthorSuppliedPdf\":false,\"isDeskRejected\":\"\",\"isHiddenFromSearch\":false,\"isInQc\":false,\"isInWorkflow\":true,\"isPdf\":false,\"isPdfUpToDate\":true,\"isWithdrawnOrRetracted\":false,\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"journal-of-cancer-research-and-clinical-oncology\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"jocr\",\"sideBox\":\"Learn more about [Journal of Cancer Research and Clinical Oncology](https://www.springer.com/journal/432)\",\"snPcode\":\"432\",\"submissionUrl\":\"https://submission.nature.com/new-submission/432/3\",\"title\":\"Journal of Cancer Research and Clinical Oncology\",\"twitterHandle\":\"\",\"acdcEnabled\":true,\"dfaEnabled\":true,\"editorialSystem\":\"em\",\"reportingPortfolio\":\"Springer Hybrid\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":false},\"keywords\":\"Non–small cell lung cancer, lung cancer screening, Safety, Chest CT\",\"lastPublishedDoi\":\"10.21203/rs.3.rs-259864/v1\",\"lastPublishedDoiUrl\":\"https://doi.org/10.21203/rs.3.rs-259864/v1\",\"license\":{\"name\":\"CC BY 4.0\",\"url\":\"https://creativecommons.org/licenses/by/4.0/\"},\"manuscriptAbstract\":\"\\u003cp\\u003e\\u003cstrong\\u003ePurpose\\u003c/strong\\u003e: Regardless of professional societies agreed that CT screening inconsistent with recommendation leads to radiation-related cancer and unexpected cost, many patients undergo unnecessary chest CT before treatment. The goal of this study was to assess the overuse of Chest CT in different type of patients.\\u003c/p\\u003e\\u003cp\\u003e\\u003cstrong\\u003eMethods:\\u003c/strong\\u003e Data on 1853 patients who underwent pulmonary resection from May 2019 to May 2020 were retrospectively analyzed. Data collected include age, sex, follow-up time, density and size of nodules and frequency of undergoing Chest CT. Pearson χ2\\u0026nbsp;test and logistic regression were conducted to compare the receipt of CT screening.\\u003c/p\\u003e\\u003cp\\u003e\\u003cstrong\\u003eResults\\u003c/strong\\u003e: Among 1853 patients in the study, 689 (37.2%) had overused Chest CT during follow-up of the lung cancer. This rate was 16.2% among patients with solid nodules, 57.5% among patients with pure ground glass opacity (pGGO), and 41.4% among patients with mixed ground glass opacity (mGGO) (P\\u0026lt;.001). 50.7% in the “age ≤40” group, 39.8% in the “41≤age ≤50” group, 38.7% in the “51≤age ≤60” group, 32.3% in the “61≤age ≤70” group, 27.8% in the “\\u0026gt;70” group underwent unnecessary CT (P\\u0026lt;.001). Female get more unnecessary CT than male (40.6% vs 32.8%,\\u0026nbsp;\\u003cem\\u003eP\\u003c/em\\u003e\\u0026lt;.001). Factors associated with a greater likelihood of Chest CT is the density of nodules (odds ratios [ORs] of 0.53 for mGGO; 0.15 for solid nodule, P\\u0026lt;.0001, vs patients with pGGO).\\u003c/p\\u003e\\u003cp\\u003e\\u003cstrong\\u003eConclusion\\u003c/strong\\u003e: roughly 37% patients with pulmonary nodules received Chest CT too frequently despite national recommendations against the practice. Closer adherence to clinical guidelines is likely to result in more cost-effective care.\\u003c/p\\u003e\",\"manuscriptTitle\":\"Overuse of Follow-up Chest Computed Tomography in Patients With Incidentally Identified Nodules Suspicious for Lung Cancer\",\"msid\":\"\",\"msnumber\":\"\",\"nonDraftVersions\":[{\"code\":1,\"date\":\"2021-03-16 22:24:40\",\"doi\":\"10.21203/rs.3.rs-259864/v1\",\"editorialEvents\":[{\"type\":\"communityComments\",\"content\":0},{\"type\":\"decision\",\"content\":\"Major revisions needed\",\"date\":\"2021-04-16T12:12:20+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"reviewersInvited\",\"content\":\"\",\"date\":\"2021-03-11T00:00:00+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorAssigned\",\"content\":\"\",\"date\":\"2021-02-23T00:00:00+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"submitted\",\"content\":\"Journal of Cancer Research and Clinical Oncology\",\"date\":\"2021-02-19T11:09:35+00:00\",\"index\":\"\",\"fulltext\":\"\"}],\"status\":\"published\",\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"journal-of-cancer-research-and-clinical-oncology\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"jocr\",\"sideBox\":\"Learn more about [Journal of Cancer Research and Clinical Oncology](https://www.springer.com/journal/432)\",\"snPcode\":\"432\",\"submissionUrl\":\"https://submission.nature.com/new-submission/432/3\",\"title\":\"Journal of Cancer Research and Clinical Oncology\",\"twitterHandle\":\"\",\"acdcEnabled\":true,\"dfaEnabled\":true,\"editorialSystem\":\"em\",\"reportingPortfolio\":\"Springer Hybrid\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":false}}],\"origin\":\"\",\"ownerIdentity\":\"0c1842cf-cc6b-4027-8c3c-74be322f12a9\",\"owner\":[],\"postedDate\":\"March 16th, 2021\",\"published\":true,\"recentEditorialEvents\":[],\"rejectedJournal\":[],\"revision\":\"\",\"amendment\":\"\",\"status\":\"published-in-journal\",\"subjectAreas\":[{\"id\":2998079,\"name\":\"Cancer Biology\"},{\"id\":2998080,\"name\":\"Oncology\"}],\"tags\":[],\"updatedAt\":\"2021-08-10T15:04:00+00:00\",\"versionOfRecord\":{\"articleIdentity\":\"rs-259864\",\"link\":\"https://doi.org/10.1007/s00432-021-03692-6\",\"journal\":{\"identity\":\"journal-of-cancer-research-and-clinical-oncology\",\"isVorOnly\":false,\"title\":\"Journal of Cancer Research and Clinical Oncology\"},\"publishedOn\":\"2021-07-08 15:00:39\",\"publishedOnDateReadable\":\"July 8th, 2021\"},\"versionCreatedAt\":\"2021-03-16 22:24:40\",\"video\":\"\",\"vorDoi\":\"10.1007/s00432-021-03692-6\",\"vorDoiUrl\":\"https://doi.org/10.1007/s00432-021-03692-6\",\"workflowStages\":[]},\"version\":\"v1\",\"identity\":\"rs-259864\",\"journalConfig\":\"researchsquare\"},\"__N_SSP\":true},\"page\":\"/article/[identity]/[[...version]]\",\"query\":{\"redirect\":\"/article/rs-259864\",\"identity\":\"rs-259864\",\"version\":[\"v1\"]},\"buildId\":\"-HB7Z8yhvgn0wM9Nzuekk\",\"isFallback\":false,\"isExperimentalCompile\":false,\"dynamicIds\":[84888],\"gssp\":true,\"scriptLoader\":[]}","source_license":"CC-BY-4.0","license_restricted":false}