TNM Classification For Lung Cancer Research Articles

The International Association for the Study of Lung Cancer Lung Cancer Staging Project: Proposals for Revision of the Classification of Residual Tumor After Resection for the Forthcoming (Ninth) Edition of the TNM Classification of Lung Cancer

IntroductionThe goal of surgical resection is to completely remove a cancer; it is useful to have a system to describe how well this was accomplished. This is captured by the residual tumor (R) classification, which is separate from the TNM classification that describes the anatomic extent of a cancer independent of treatment. The traditional R-classification designates as R0 a complete resection, as R1 a macroscopically complete resection but with microscopic tumor at the surgical margin, and as R2 a resection that leaves gross tumor behind. For lung cancer, an additional category encompasses situations in which the presence of residual tumor is uncertain. MethodsThis paper represents a comprehensive review of evidence regarding these R categories and the descriptors thereof, focusing on studies published after the year 2000 and with adjustment for potential confounders. ResultsConsistent discrimination between complete, uncertain, and incomplete resection is revealed with respect to overall survival. Evidence regarding specific descriptors is generally somewhat limited and only partially consistent; nevertheless, the data suggest retaining all descriptors but with clarifications to address ambiguities. ConclusionOn the basis of this review, the R-classification for the ninth edition of stage classification of lung cancer is proposed to retain the same overall framework and descriptors, with more precise definitions of descriptors. These refinements should facilitate application and further research.

Introduction to the 9th edition of TNM classification for lung cancer

Lung cancer is the second commonly diagnosed cancer and remained the leading cause of cancer-related death, with an estimated 1.8 million deaths in 2020. The identification of driver gene mutation and administration of corresponding tyrosine kinase inhibitor have improved overall survival and quality of life in advanced lung cancer patients. Check point inhibitor has revolutionized treatment strategy of driver gene negative advanced NSCLC patients. TNM staging system is the most widely used classification method, providing an international common language during academic communication and important tool for predicting prognosis and subsequent treatment decision making. Accumulating knowledge about prognostic factors in lung cancer promotes the update of TNM classification. In the World Conference on Lung Cancer (WCLC) held in Singapore, September, 2023, International Association for Study of Lung Cancer (IASLC) released the forthcoming 9th edition of TNM classification for lung cancer, which is supposed to be adopted at January, 2024. The manuscript discussed the history, data resource and limitation of the TNM staging system.

The International Association for the Study of Lung Cancer (IASLC) Staging Project for Lung Cancer: Recommendation to Introduce Spread Through Air Spaces as a Histologic Descriptor in the Ninth Edition of the TNM Classification of Lung Cancer. Analysis of 4061 Pathologic Stage I NSCLC

IntroductionSpread through air spaces (STAS) consists of lung cancer tumor cells that are identified beyond the edge of the main tumor in the surrounding alveolar parenchyma. It has been reported by meta-analyses to be an independent prognostic factor in the major histologic types of lung cancer, but its role in lung cancer staging is not established. MethodsTo assess the clinical importance of STAS in lung cancer staging, we evaluated 4061 surgically resected pathologic stage I R0 NSCLC collected from around the world in the International Association for the Study of Lung Cancer database. We focused on whether STAS could be a useful additional histologic descriptor to supplement the existing ones of visceral pleural invasion (VPI) and lymphovascular invasion (LVI). ResultsSTAS was found in 930 of 4061 of the pathologic stage I NSCLC (22.9%). Patients with tumors exhibiting STAS had a significantly worse recurrence-free and overall survival in both univariate and multivariable analyses involving cohorts consisting of all NSCLC, specific histologic types (adenocarcinoma and other NSCLC), and extent of resection (lobar and sublobar). Interestingly, STAS was independent of VPI in all of these analyses. ConclusionsThese data support our recommendation to include STAS as a histologic descriptor for the Ninth Edition of the TNM Classification of Lung Cancer. Hopefully, gathering these data in the coming years will facilitate a thorough analysis to better understand the relative impact of STAS, LVI, and VPI on lung cancer staging for the Tenth Edition TNM Stage Classification.

The International Association for the Study of Lung Cancer Staging Project for Lung Cancer: Proposals for the Revision of the M Descriptors in the Forthcoming Ninth Edition of the TNM Classification for Lung Cancer

IntroductionThis study analyzed all metastatic categories of the current TNM classification of NSCLC to propose modifications of the M component in the next edition (ninth) of the classification. MethodsA database of 124,581 patients diagnosed between 2011 and 2019 was established; of these, 14,937 with NSCLC in stages IVA to IVB were available for this analysis. Overall survival was calculated using the Kaplan-Meier method, and prognosis was assessed using multivariable-adjusted Cox proportional hazards regression. ResultsThe eighth edition M categories revealed good discrimination in the ninth edition data set. Assessments revealed that an increasing number of metastatic lesions were associated with decreasing prognosis; because this seems to be a continuum and adjustment for confounders was not possible, no specific lesion number was deemed appropriate for stage classification. Among tumors involving multiple metastases, decreasing prognosis was found with an increasing number of organ systems involved. Multiple assessments, including after adjustment for potential confounders, revealed that M1c patients who had metastases to a single extrathoracic organ system were prognostically distinct from M1c patients who had involvement of multiple extrathoracic organ systems. ConclusionsThese data validate the eighth edition M1a and M1b categories, which are recommended to be maintained. We propose the M1c category be divided into M1c1 (involvement of a single extrathoracic organ system) and M1c2 (involvement of multiple extrathoracic organ systems).

The International Association for the Study of Lung Cancer Lung Cancer Staging Project: Proposals for the Revisions of the T-Descriptors in the Forthcoming Ninth Edition of the TNM Classification for Lung Cancer

IntroductionAn international database was created by the International Association for the Study of Lung Cancer to inform on the ninth edition of the TNM classification of lung cancer. The present analyses concern its T component. MethodsData on 124,581 patients diagnosed with lung cancer from January 1, 2011 to December 31, 2019 were submitted to the International Association for the Study of Lung Cancer database. Of these, 33,982 met the inclusion criteria for the clinical T analysis, and 30,715 met the inclusion criteria for the pathologic postsurgical analysis. Survival was measured from the date of diagnosis or operation for clinically and pathologically staged tumors, respectively. T descriptors were evaluated in univariate analysis and multivariable Cox regression analysis adjusted for age, sex, pathologic type, and geographic region. ResultsComprehensive survival analysis revealed that the existing eighth edition T component criteria performed adequately in the ninth edition data set. Although pathologic chest wall or parietal pleura involvement (PL 3) yielded a worse survival compared with the other T3 descriptors, with a similar survival as T4 tumors, this difference was not observed for clinical chest wall or PL 3 tumors. Because of these inconsistent findings, no reallocation of chest wall or PL 3 tumors is advised. ConclusionsThe T subcommittee members proposed not to implement any changes and keep the current eighth-edition T descriptors for the ninth edition.

Development and validation of a nomogram prognostic model for small cell lung cancer optimized by age and metastatic pattern

Background: The objective of this study is to establish and validate a novel nomogram by optimizing the eighth edition of the TNM classification by adding age and metastatic pattern. Methods: Clinical data of 1085 patients with small cell lung cancer (SCLC) from a Chinese multi-institutional registry were subjected to bootstrap external validation based on a prognostic nomogram built by integrating significant prognostic factors for survival from 21,707 cases from the Surveillance, Epidemiology, and End Results (SEER) database (training cohort). Kaplan–Meier survival analyses and concordance index (c-index) were used to test the application of the risk stratification system. Results: Both cohorts exhibited significant mortality increases with age (SEER hazard ratio [HR], 1.319; China HR, 1.237; both P < 0.001). The patterns of organ metastasis, liver (HR = 3.219), lung (HR = 1.750), brain (HR = 1.509), and bone (HR = 2.614), had significantly disparate prognoses. The nomogram based on the TNM classification of lung cancer was optimized by age and organ metastatic pattern, with an improvement in the C-index (from 0.617 to 0.661 in the training cohort and from 0.620 to 0.668 in the external validation cohort). Conclusion: This model provides useful quantitative tool for physicians to make critical diagnostic and treatment decisions for patients with SCLC.

The International Association for the Study of Lung Cancer Staging Project for Lung Cancer: Proposals for the Revision of the N Descriptors in the Forthcoming Ninth Edition of the TNM Classification for Lung Cancer

IntroductionThe accurate assessment of nodal (N) status is crucial to the management and prognostication of nonmetastatic NSCLC. We sought to determine whether the current N descriptors should be maintained or revised for the upcoming ninth edition of the international TNM lung cancer staging system. MethodsData were assembled by the International Association for the Study of Lung Cancer on patients with NSCLC, detailing both clinical and pathologic N status, with information about anatomical location and individual station-level identification. Survival was calculated by the Kaplan-Meier method and prognostic groups were assessed by a Cox regression analysis. ResultsData for clinical N and pathologic N status were available in 45,032 and 35,009 patients, respectively. The current N0 to N3 descriptors for both clinical N and pathologic N categories reflect prognostically distinct groups. Furthermore, single-station N2 involvement (N2a) exhibited a better prognosis than multistation N2 involvement (N2b) in both clinical and pathologic classifications, and the differences between all neighboring nodal subcategories were highly significant. The prognostic differences between N2a and N2b were robust and consistent across resection status, histologic type, T category, and geographic region. ConclusionsThe current N descriptors should be maintained, with the addition of new subdescriptors to N2 for single-station involvement (N2a) and multiple-station involvement (N2b).

A problem with clinical T factor in the 8th TNM edition: Prognosis and EGFR mutation status of small sized lung cancers with difficulty to measure the diameter of solid component in part-solid tumor

ObjectiveClinical T factors in the 8th TNM classification of lung cancer have a practical problem. In some cases, it is difficult to measure the size of the solid components in part-solid tumors, and the classification of these tumors is controversial. MethodsWe evaluated 590 resected cT1N0M0 stage IA non-small-cell lung cancers based on the 7th edition between 2009 and 2012. Tumor and solid component diameters were measured using thin-section computed tomography (CT). We defined tumors with difficulty in measuring the size of the solid components as lung cancers with scattered or mixed consolidation (LCSMCs). LCSMCs were observed in 79 (13.4%) patients. Other tumors were classified as cTis, cT1mi, cT1a, cT1b, and cT1c, according to the 8th edition. We compared prognosis and epidermal growth factor receptor mutations (EGFRm) status of LCSMCs with those of cT1a, cT1b, and cT1c. ResultsThe difference in overall survival (OS) among cT1a, cT1b, and cT1c was significant (5-year-OS: 96.9% vs. 76.8% vs. 65.0%). There was no significant difference in prognosis between LCSCs and cT1a (5-year-OS: 92.4% vs. 96.9%). A significant difference was observed in the frequency of EGFRm between cT1a, cT1b, and cT1c (52.4%, 42.4%, and 29.8%). The incidence of EGFRm in LCSMCs was 54.8% and there was no significant difference between LCSMCs and cT1a. ConclusionsThe prognosis and frequency of EGFRm in LCSMCs were close to those in cT1a. As we cannot measure the diameter of the solid component in subsolid lung cancers, it may be appropriate to classify these tumors as cT1a tumors.

68Ga-SSO-120 PET for Initial Staging of Small Cell Lung Cancer Patients: A Single-Center Retrospective Study.

PET imaging using the somatostatin receptor 2 (SSTR2) antagonist satoreotide trizoxetan (SSO-120, previously OPS-202) could offer accurate tumor detection and screening for SSTR2-antagonist radionuclide therapy in patients with SSTR2-expressing small cell lung cancer (SCLC). The aim of this single-center study was to investigate tumor uptake and detection rates of 68Ga-SSO-120 in comparison to 18F-FDG PET in the initial staging of SCLC patients. Methods: Patients with newly diagnosed SCLC who underwent additional whole-body 68Ga-SSO-120 PET/CT during the initial diagnostic workup were retrospectively included. The mean administered activity was 139 MBq, and the mean uptake time was 60 min. Gold-standard staging 18F-FDG PET/CT was evaluated if available within 2 wk before or after 68Ga-SSO-120 PET if morphologic differences in CT images were absent. 68Ga-SSO-120- or 18F-FDG-positive lesions were reported in 7 anatomic regions (primary tumor, thoracic lymph node metastases, and distant metastases including pleural, contralateral pulmonary, liver, bone, and other) according to the TNM classification for lung cancer (eighth edition). Consensus TNM staging (derived from CT, endobronchial ultrasound-guided transbronchial needle aspiration, PET, and brain MRI) by a clinical tumor board served as the reference standard. Results: Thirty-one patients were included, 12 with limited and 19 with extensive disease according to the Veterans Administration Lung Study Group classification. 68Ga-SSO-120-positive tumor was detected in all patients (100%) and in 90 of the 217 evaluated regions (41.5%). Thirteen patients (42.0%) had intense average 68Ga-SSO-120 uptake (region-based mean SUVmax ≥ 10); 28 patients (90.3%) had average 68Ga-SSO-120 uptake greater than liver uptake (region-based mean peak tumor-to-liver ratio > 1). In 25 patients with evaluable 18F-FDG PET, primary tumor, thoracic lymph node metastases, and distant metastases were detected in 100%, 92%, and 64%, respectively, of all investigated patients by 68Ga-SSO-120 and in 100%, 92%, and 56%, respectively, by 18F-FDG PET. 68Ga-SSO-120 PET detected additional contralateral lymph node, liver, and brain metastases in 1, 1, and 2 patients, respectively (no histopathology available), and 18F-FDG PET detected additional contralateral lymph node metastases in 3 patients (1 confirmed, 1 systematic endobronchial ultrasound-guided transbronchial needle aspiration-negative, and 1 without available histopathology). None of these differences altered Veterans Administration Lung Study Group staging. The region-based monotonic correlation between 68Ga-SSO-120 and 18F-FDG uptake was low (Spearman ρ = 0.26-0.33). Conclusion: 68Ga-SSO-120 PET offers high diagnostic precision with comparable detection rates and additional complementary information to the gold standard, 18F-FDG PET. Consistent uptake in most patients warrants exploration of SSTR2-directed radionuclide therapy.

IASLC Lung Cancer Staging Project: The New Database to Inform Revisions in the Ninth Edition of the TNM Classification of Lung Cancer

In the past 20 years, the International Association for the Study of Lung Cancer (IASLC) has been working on a global project to revise the TNM classification of lung cancer. The first and second phases of the staging projects proposed recommendations for revision of the TNM classification, which were adopted by the Union for International Cancer Control and the American Joint Committee on Cancer as their seventh and eighth editions of the TNM classifications of lung cancer. For the third phase of the IASLC Staging Project, a new database of lung cancer cases diagnosed between January 2011 and December 2019 has been established. The Staging and Prognostic Factors Committee of the IASLC is in charge of the process of proposing new recommendations. The newly established database consisted of 124,581 cases. The data were obtained from Asia and Australia (56.0%), Europe (24.7%), North America (15.7%), South/Central America (3.4%), and Africa and the Middle East (0.1%). After cases with incomplete data are excluded, 87,043 cases were enrolled in the analysis, of which 52,069 (59.8%) were invasive adenocarcinoma and 15,872 (18.2%) were squamous cell carcinoma. Both clinical and pathologic stages were available in 44,831 (51.5%) cases. Analyses of this database are expected to provide proposals for changing the TNM classification toward the ninth edition, which is scheduled to be in use in January 2024. This newly established global database on lung cancer is described to provide fundamental elements for revisions of the TNM rules for staging lung cancer.

External validation of the eighth edition of the TNM classification for lung cancer in small cell lung cancer

ObjectivesThe newly released eighth edition of the American Joint Committee on Cancer TNM staging system for lung cancer seeks to improve prognostic accuracy but lacks external validation for small cell lung cancer (SCLC). Moreover, previous studies posed a few questions concerning survival differences for patients with specific site N3 node involvement or single-site metastasis (SSM) in different distant organs. The aim of this study was to validate the eighth edition of the TNM classification for SCLC in an independent multi-institutional cohort from China and answer the questions raised by the previous research. MethodsPatients with SCLC from four Chinese cancer centers between 2009 and 2019 were reclassified according to the seventh and eighth edition of the TNM classification. Survival was estimated using the Kaplan-Meier method. Comparisons between adjacent categories and stage groups were performed using Cox proportional hazard regression. R2 statistics were calculated to evaluate the discriminating performance of editions. ResultsOf 3384 enrolled cases, 3358 had clinical stage, 537 had pathological stage, and 511 had both. Progressive deterioration of survival was observed with advancing of TNM categories and stages both in the seventh and the eighth edition. The eighth edition stages had a higher R2 statistic than the seventh edition (0.207 versus 0.197). Newly defined categories M1b and M1c and stages IIIC, IVA and IVB in the eighth edition discriminated groups with significantly different prognosis. Patients with N3 contralateral supraclavicular nodes had a significantly worse prognosis than those without (p = 0.032). For patients with single-site metastasis, liver involvement showed a worse prognosis compared to brain involvement (p = 0.030). ConclusionsOur study provided an external validation of the eighth edition of the TNM classification for lung cancer in Chinese patients with SCLC, and confirmed its improved prognostic accuracy compared with the seventh edition. Patients with N3 and M1b might represent heterogeneous populations that warrant further research.

Prognosis of pulmonary lymphangitic carcinomatosis in patients with non-small cell lung cancer.

BackgroundThe eighth edition of the TNM classification for lung cancer does not provide a definite guideline for pulmonary lymphangitic carcinomatosis. The purpose of this retrospective case-control study is to evaluate the prognosis of pulmonary lymphangitic carcinomatosis in patients with non-small cell lung cancer compared with those with intrapulmonary metastases.MethodsNon-small cell lung cancer (NSCLC) patients with pulmonary lymphangitic carcinomatosis detected on chest computed tomography scan during staging evaluation between 2000 and 2016 were included. The extent of pulmonary lymphangitic carcinomatosis was classified as being around the primary tumor (cLy1), at a distance from the tumor but confined to the same lobe (cLy2), in other ipsilateral lobes (cLy3), or affecting the contralateral lung (cLy4). Overall survival rates of the subjects were compared with those with intrapulmonary metastases.ResultsA total of 103 subjects with pulmonary lymphangitic carcinomatosis were analysed. The 5-year overall survival rates of the subjects with pulmonary lymphangitic carcinomatosis (n=103) and intrapulmonary metastases (n=111) were 33% and 21%, respectively. The 5-year overall survival rates of cLy1 (n=28), cLy2 (n=40), cLy3 (n=26) and cLy4 (n=9) were 54%, 35%, 12% and 11%, respectively. On multivariable analyses after adjusting for possible confounders, the subjects with cLy1 and cLy2 had better overall survival (adjusted hazard ratio for death, 0.34 and 0.49; 95% confidence interval, 0.24–0.73 and 0.30–0.80; P<0.001 and 0.004, respectively) and the subjects with cLy4 had worse overall survival (adjusted hazard ratio, 2.21; 95% confidence interval, 1.03–4.70; P=0.040) compared with those with intrapulmonary metastases.ConclusionsThe subjects with cLy1/2 had better overall survival than those with cLy3/4 or intrapulmonary metastases. cLy1/2 seems to be a T descriptor (T3/4) rather than an M1 descriptor.

Systemic immune-inflammation index is a stage-dependent prognostic factor in patients with operable non-small cell lung cancer.

BackgroundImmune function is a key component affecting tumor progression in patients with cancer. The purpose of this study was to identify the prognostic value of systemic immune-inflammation index (SII) in patients with non-small cell lung cancer (NSCLC) and the differences of its prognostic value in patients with distinct characteristics.MethodsPatients with completely resected NSCLC were reviewed according to the eighth TNM classification of lung cancer. Patients were further categorized into the low- and high-SII groups. Cox proportional hazard analyses were performed to identify the independent prognostic factors.ResultsA total of 3984 patients with NSCLC were enrolled in this study. Kaplan-Meier analyses demonstrated that high SII was associated with worse recurrence-free survival (RFS) (P<0.001) and overall survival (OS) (P<0.001). Cox proportional hazard analyses revealed that SII was an independent risk factor for worse RFS (P=0.038) and OS (P=0.043). Further analyses demonstrated that the prognostic value of SII was observed only in patients with stage I disease (P<0.001), solid nodules (P=0.002), or adenocarcinoma (P<0.001). Sensitivity analyses using multiple imputation and competing risk analyses also confirmed similar results.ConclusionsSII was associated with worse survival independently, and its prognostic role was exhibited solely in NSCLC patients with stage I disease, solid nodules, and adenocarcinoma. This study helped us specify the target population for clinical use of SII.

Commemorating the Silver Anniversary of the International Association for the Study of Lung Cancer International Workshop on Intrathoracic Staging

Commemorating the Silver Anniversary of the International Association for the Study of Lung Cancer International Workshop on Intrathoracic Staging

Evaluation of Eighth AJCC TNM Sage for Lung Cancer NSCLC: A Meta-analysis.

The AJCC 8th edition TNM classification for lung cancer was released in 2017. This edition has made major changes in many tumor descriptors including sites of metastasis. The new staging system has been a subject of multiple validation studies, of which many have had mixed results. The present study is designed to critically evaluate the results of these external validation studies. A metaanalysis of these external validation studies was performed to critically evaluate the new staging system. Out of 12 studies, 8 were found to fulfill the eligibility criteria, with 654,185 patients being included in the analysis. Hazard ratios (HRs) and associated 95% confidence intervals (CI) extracted from these studies were utilized for analysis. The primary outcomes were survival discrimination and prognostic ability of the 8th edition compared with the 7th edition. The HRs for the 8th edition staging system were 1.41 in IB, 1.64 in IIA, 1.24 in IIB, 1.95 in IIIA, 3.96 in IIIB, and 4.82 in IIIC compared with IA. The new edition fared better than the 7th edition in survival discrimination in all but stage IIA and IIB. The C-index of the 8th and 7th editions was 0.690 and 0.688, respectively, suggesting almost similar prognostic values. This study shows that the survival discrimination of the 8th edition fared better than the 7th edition in all but stage IIA and IIB. The prognostic value of the two staging systems is similar, with no added advantage of the new edition.

The 8th Edition of the TNM Classification for Lung Cancer

The 8th Edition of the TNM Classification for Lung Cancer

8th Edition Tumor, Node, and Metastasis T-Stage Prognosis Discrepancies: Solid Component Diameter Predicts Prognosis Better than Invasive Component Diameter.

The biggest change in the 8th edition of the tumor, lymph node, and metastasis (TNM) classification is the recommendation of the solid component diameter and invasive size for determining the clinical and pathological T-factor, respectively. Here, we validated new proposals for the Lung Cancer TNM classification’s revision and compared clinical and pathological T-stages. We retrospectively analyzed 177 cases of non-small cell lung cancers without lymph node metastasis, and involving complete resection, that occurred in our department between January 2017 and March 2019. We reviewed the overall tumor diameter, solid component diameter, and clinical T-factor on computed tomography (CT), and the pathological tumor diameter, pathological invasion diameter, pathological T-factor, and prognosis. The difference between the pathological invasive size and solid size on CT was within 5 mm in 99 cases (56%). At a two-year recurrence-free survival rate, the clinical T-stage demonstrated a better prognostic outcome than the pathological T-stage. Despite including the benign findings, the solid component diameter was better correlated with prognosis than the invasive size. Therefore, in cases of discrepancies of clinically and pathologically detected tumor size, the solid CT size should also be used for the pathological T classification.

Risk Factors for Occult Lymph Node Metastasis in Peripheral Non-Small Cell Lung Cancer with Invasive Component Size 3cm or Less.

In the seventh edition TNM staging system for lung cancer, a high maximum standardized uptake value (SUVmax) on positron emission tomography was regarded as a risk factor for occult lymph node metastasis in clinical T1N0 non-small cell lung cancer (NSCLC). However, in the eighth edition TNM classification, tumors are classified according to the size of the invasive component only, and those with invasive component size ≤3cm are diagnosed as stage T1. The aim of this study was to reassess the risk factors for occult lymph node metastasis under the eighth edition TNM classification for lung cancer. From 2010 to 2017, 553 patients with clinical N0 peripheral NSCLC with invasive component size ≤3cm underwent anatomical lobectomy with systematic lymph node dissection. We analyzed these cases retrospectively to identify risk factors for postoperative nodal upstaging. Among 553 study patients, 54 (9.8%) had nodal upstaging after surgery. In multivariate analysis adopting the eighth edition TNM classification for lung cancer, serum carcinoembryonic antigen (CEA) level (hazard ratio [HR] = 1.113, p = 0.002), invasive component size (HR = 2.398, p = 0.004), visceral pleural invasion (HR = 2.901, p = 0.005), and lymphatic invasion (HR = 9.336, p < 0.001) were significant risk factors for nodal upstaging, but SUVmax was not. SUVmax is not a predictor of nodal upstaging in clinical N0 peripheral NSCLC with invasive component size ≤3cm under the eighth edition TNM classification for lung cancer. Significant risk factors of occult lymph node metastasis are serum CEA level, tumor invasive component size, visceral pleural invasion, and lymphatic invasion.

T4 disease: exploring changes in the 8th edition of the TNM classification of lung cancer and pushing the limits.

T4 disease: exploring changes in the 8th edition of the TNM classification of lung cancer and pushing the limits.

WS04.02 Challenges in Imaging Evaluation to Enter Data in the IASLC Database

Soon after the publication of the proposals for the 8thedition of the TNM staging system, the International Association for the Study of Lung Cancer (IASLC) opened a new database for data collection for the next iteration of the lung cancer staging system (1). The database contains more than 450 fields, which address data on patient characteristics, baseline laboratory values, as well as the results of pulmonary function, imaging, and pathological tests. As the database collects the data about lung cancer newly diagnosed between January 1, 2011, and December 31, 2019, the data entered might be predominantly retrospectively collected in some centers. From an imaging perspective, this might lead to a number of problems. First, at least some of the elements required by the database might not be mentioned in the radiological reports. This may necessitate a re-evaluation of the imaging studies by an experienced radiologist, which might not be possible in all centers. Furthermore, the levels of training of the radiologists and reporting across different countries may be variable and thus introduce some degree of imprecision into the quality of the data. As an example, in T staging, particular attention has to be paid to thorough measurements to ensure that the largest diameter in the axial, coronal, or sagittal plane is measured (2). Caution should also be taken not to overdiagnose additional pulmonary nodules as metastases. In N staging, particular attention has to be paid to the lymph node atlas-mining, particularly the well-known pitfall in the correct assignment of lymph nodes at levels 4 and 10 (3-5). Furthermore, the quality of imaging and the availability of more advanced/expensive imaging techniques may also vary from country to country. As an example, the availabilities of PET/CT and/or MRI are not homogenous all over the globe. However, if PET/CT is not performed routinely in operable patients, as many as 20% of unexpected distant metastases might be missed (6). Future staging projects should specifically address these issues in order to further improve the the quality of data necessary to improve the next iteration of the staging system. 1. Giroux DJ, Van Schil P, Asamura H, Rami-Porta R, Chansky K, Crowley JJ, et al. The IASLC Lung Cancer Staging Project: A Renewed Call to Participation. J Thorac Oncol. 2018;13(6):801-9. 2. Travis WD, Asamura H, Bankier AA, Beasley MB, Detterbeck F, Flieder DB, et al. The IASLC Lung Cancer Staging Project: Proposals for Coding T Categories for Subsolid Nodules and Assessment of Tumor Size in Part-Solid Tumors in the Forthcoming Eighth Edition of the TNM Classification of Lung Cancer. J Thorac Oncol. 2016. 3. El-Sherief AH, Lau CT, Obuchowski NA, Mehta AC, Rice TW, Blackstone EH. Cross-Disciplinary Analysis of Lymph Node Classification in Lung Cancer on CT Scanning. Chest. 2017;151(4):776-85. 4. El-Sherief AH, Lau CT, Wu CC, Drake RL, Abbott GF, Rice TW. International association for the study of lung cancer (IASLC) lymph node map: radiologic review with CT illustration. Radiographics. 2014;34(6):1680-91. 5. Aviram G, Revel MP. Misclassification of Lymph Nodes in Lung Cancer Staging: Can We Improve? Chest. 2017;151(4):733-4. 6. Fischer B, Lassen U, Mortensen J, Larsen S, Loft A, Bertelsen A, et al. Preoperative Staging of Lung Cancer with Combined PET-CT. N Engl J Med. 2009;361(1):32-9. staging, TNM, Lung cancer