A system for the clinical staging of lung cancer

The International Association for the Study of Lung Cancer Lung Cancer Staging Project: Proposals for Revision of the TNM Stage Groups in the Forthcoming (Ninth) Edition of the TNM Classification for Lung Cancer

INTRODUCTION

The TNM classification of lung cancer is periodically revised. The International Association for the Study of Lung Cancer collected and analyzed a new database to inform the forthcoming ninth edition of the TNM classification. The results are herewith presented.

METHODS

After exclusions, 76,518 patients from a total of 124,581 registered patients were available for analyses: 58,193 with clinical stage, 39,192 with pathologic stage, and 62,611 with best stage NSCLC. The proposed new N2 subcategories (N2a, involvement of single ipsilateral mediastinal or subcarinal nodal station, and N2b, involvement of multiple ipsilateral mediastinal nodal stations with or without involvement of the subcarinal nodal station) and the new M1c subcategories (M1c1, multiple extrathoracic metastases in one organ system, and M1c2, multiple extrathoracic metastases in multiple organ systems) were considered in the survival analyses. Several potential stage groupings were evaluated, using multiple analyses, including recursive partitioning, assessment of homogeneity within and discrimination between potential groups, clinical and statistical significance of survival differences, multivariable regression, and broad assessment of generalizability.

RESULTS

T1N1, T1N2a, and T3N2a subgroups are assigned to IIA, IIB, and IIIA stage groups, respectively. T2aN2b and T2bN2b subgroups are assigned to IIIB. M1c1 and M1c2 remain in stage group IVB. Analyses reveal consistent ordering, discrimination of prognosis, and broad generalizability of the proposed ninth edition stage classification of lung cancer.

CONCLUSIONS

The proposed stages for the ninth edition TNM improve the granularity of nomenclature about anatomic extent that has benefits as treatment approaches become increasingly differentiated and complex.

Investigating the Clinico-Molecular and Immunological Evolution of Lung Adenocarcinoma Using Pseudotime Analysis

Introduction

As the molecular features of lung adenocarcinoma (LUAD) have been evaluated as a cross-sectional study, the course of tumor characteristics has not been modeled. The temporal evolution of the tumor immune microenvironment (TIME), as well as the clinico-molecular features of LUAD, could provide a precise strategy for immunotherapy and surrogate biomarkers for the course of LUAD.

Methods

A pseudotime trajectory was constructed in patients with LUAD from the Cancer Genome Atlas and non-small cell lung cancer radiogenomics datasets. Correlation analyses were performed between clinical features and pseudotime. Genes associated with pseudotime were selected, and gene ontology analysis was performed. F-18 fluorodeoxyglucose positron emission tomography images of subjects were collected, and imaging parameters, including standardized uptake value (SUV), were obtained. Correlation analyses were performed between imaging parameters and pseudotime. Correlation analyses were performed between the enrichment scores of various immune cell types and pseudotime. In addition, correlation analyses were performed between the expression of PD-L1, tumor mutation burden, and pseudotime.

Results

Pseudotime trajectories of LUAD corresponded to clinical stages. Molecular profiles related to cell division and natural killer cell activity were changed along the pseudotime. The maximal SUV of LUAD tumors showed a positive correlation with pseudotime. Type 1 helper T (Th1) cells showed a positive correlation, whereas M2 macrophages showed a negative correlation with pseudotime. PD-L1 expression showed a negative correlation, whereas tumor mutation burden showed a positive correlation with pseudotime.

Conclusion

The estimated pseudotime associated with the stage suggested that it could reflect the clinico-molecular evolution of LUAD. Specific immune cell types in the TIME as well as cell division and glucose metabolism were dynamically changed according to the progression of the pseudotime. As a molecular progression of LUAD, different cellular targets should be considered for immunotherapy.

Lung Cancer Staging

Anatomic staging is a critical step in evaluation of patients with lung cancer. Accurate identification of stage based on features of primary tumor (T), regional nodes (N), and metastatic disease (M) is fundamental to determining appropriate care. In this article, the TNM components of the anatomic staging system and a framework for description of lung cancer with multiple pulmonary sites of involvement are discussed. TNM combinations are grouped according to prognosis, with patient-level, tumor-level, and environment-level factors also influencing survival outcomes. Although the staging system does not include molecular and immunologic information, anatomic staging remains the common language for communicating extent of disease.

Determination of prognostic factors of surgically treated pathological Stage IIIA non-small cell lung cancer

Background

This study aims to identify the prognostic factors in Stage IIIA non-small cell lung cancer and to investigate whether there was a significant difference in terms of overall survival and diseasefree survival among the subgroups belonging to this disease stage.

Methods

Between January 2010 and December 2018, a total of 144 patients (125 males, 19 females; median age 60 years; range, 41 to 80 years) who were operated for non-small cell lung cancer in our clinic and whose pathological stage was reported as IIIA were retrospectively analyzed. Data including demographic and clinical characteristics of the patients, histopathological diagnosis, the standardized uptake value of the mass on positron emission tomography-computed tomography, tumor diameter, type of surgery, lymph node metastasis status, visceral pleural invasion, and overall and disease-free survival rates were recorded.

Results

The median survival was 39 (range, 27.8 to 46.1) months and the five-year overall survival rate was 28%. The mean tumor diameter was 4.3±2.7 cm. The median disease-free survival was 37 (range, 28.1 to 48.6) months and the five-year disease-free survival rate was 26.9%. In the multivariate analysis, overall survival and disease-free survival in T2N2M0 subgroup were significantly worse than the other subgroups. The other poor prognostic factors of survival were the standardized uptake value of the tumor, pneumonectomy, and histopathological subtypes other than squamous cell carcinoma and adenocarcinoma. Parietal pleural invasion was significantly associated with worse disease-free survival rates.

Conclusion

Our results showed that there may be significant survival differences between subgroups created by tumor histopathology, lymph node invasion and the type of surgery in a heterogeneous lung cancer stage.

[Surgical Treatment of Lung Cancer: How Has the Introduction of the 8th Edition of the TNM Classification Affected Guideline-Based Therapy?]

STUDY AIM

The 8th edition of the TNM classification combined with the latest update of the S3-guideline (by AWMF/Scientific Medical Societies in Germany) on prevention, diagnosis, therapy and follow-up of lung cancer led to several changes in staging and treatment of lung cancer. The aim of this study was to identify differences in the distribution of patients due to changes from the 7th to the 8th edition that affected staging. The influence on surgical therapy will be discussed by using the recommendations of the latest S3 guideline.

METHODS

Prospective analysis of all primary cases at two thoracic surgical centres in the year 2016 and follow-up in March 2019. Comparison of the 7th edition of tumour classification for lung cancer with the 8th edition, focused on changes in tumour staging and its effects on the appropriate surgical therapy according to the latest S3 guideline.

RESULTS

A total of 432 primary cases comprised the study population. According to the 8th edition, 82 patients (7th edition: n = 85) in stage I, 43 (n = 49) patients in stage II, 100 (n = 91) patients in stage III and 207 (n = 207) patients are assigned to stage IV. 81 changes (18.7%) were detected (77 upgrades vs. 4 downgrades). 63 patients (14.6%) exhibited a different graduation within the stages. 18 patients (4.1%) were classified in different tumour stages. As a result, fewer patients (n = 12; 2.8%) should have surgery according to the latest S3 guidelines. 290 patients (67.1%) were classified to new subgroups (IA1-3, IIIC and IVA/B). Two-year survival was significantly higher in IVA (25.2%) vs. IVB (13.0%) patients (p < 0.05).

CONCLUSION

The 8th edition of the TNM-classification affords a higher level of differentiation. In this study, the new TNM classification led to a shift in the distribution, with a tendency to increase the tumour stage. This is mainly caused by changes in the T-descriptor and stage grouping. As a result, fewer patients in stage I - IIIA should have surgery according to the latest S3 guidelines. A significantly higher two-year survival rate was detected in stage IVA (M1a and M1b) compared to IVB and justifies the new differentiation due to the metastatic pattern.

Usefulness of Positron Emission Tomography in the Examination of Hilar and Mediastinal Lymphadenopathies in Patients with Suspicion of Lung Cancer

Introduction

Lung cancer is a major health problem. Mediastinal staging performed with the aid of imaging techniques is essential for appropriate disease treatment and prognosis. Accordingly, this study aimed to ascertain the usefulness of positron emission tomography (PET) in mediastinal staging, establish the best maximum standardized uptake value (SUV_max) cutoff point, compare its usefulness to that of computed tomography (CT), and determine the influence of histological tumour subtype.

Methods

We conducted a retrospective study across a period of 3 years on 128 patients with suspicion of lung cancer and analyzed their demographic and radiological characteristics using CT and PET to perform the mediastinal examination. Histology was regarded as the gold standard.

Results

PET displayed a high sensitivity (95%) and negative predictive value (NPV) (92%), outperforming CT (89% and 85%, respectively). Percentage agreement with histology was also higher (0.207 and 0.241 for CT and PET, respectively; p < 0.001). Taking an SUV_max value of 0.5 as that which would ensure greatest diagnostic accuracy, S and NPV were 100%, though percentage agreement did not increase (0.189; p < 0.001). PET discriminatory power was not affected by histological tumour subtype.

Conclusions

The results of our study indicate that PET might be a useful test for examination of the mediastinum in lung cancer patients. Its high NPV suggests that the absence of mediastinal uptake could be used to proceed to surgical treatment without the need for further tests or examinations. Nevertheless, studies directly aimed to answer this specific question are needed.

Possibilities of Combined Surgical Treatment of Lung Tumours and Heart Diseases

The purpose of the study was a retrospective evaluation of the outcome of surgical therapy of lung cancer in patients where there was concomitant cardiac disease and who underwent a cardiac operation either because of ischemic heart disease or because of valvular disease. These patients were operated on at various time intervals (two to ten months) after their cardiac operation. Some patients had their lung cancer surgery after the cardiac operation because of the high risk of possible cardiac postoperative complications; in one patient the lung operation preceded the cardiac one.

Current Controversies in Lung Cancer Staging

Lung cancer remains the leading cause of cancer-related mortality in the United States, and accurate staging of disease plays an important role in the formulation of treatment strategies and optimization of patient outcomes. The International Association for the Study of Lung Cancer has recently proposed changes to the upcoming eighth edition of the tumor, node, and metastasis (TNM-8) staging system used for lung cancer. This revised classification is based on significant differences in patient survival identified on analysis of a new large international database of lung cancer cases. Key changes include: further modifications to the T descriptors based on 1 cm increments in tumor size; grouping of tumors resulting in partial or complete lung atelectasis/pneumonitis; grouping of tumors involving a main bronchus with respect to distance from the carina; reassignment of diaphragmatic invasion; elimination of mediastinal pleural invasion as a descriptor; and further subdivision of metastatic disease into distinct descriptors based on the number of extrathoracic metastases and involved organs. Because of these changes, several new stage groups have been developed, and others have shifted. Although TNM-8 represents continued improvement upon modifications previously made to the staging system, reflecting an evolving understanding of tumor behavior and patient management, several limitations and unaddressed issues persist. Understanding the proposed revisions to TNM-8 and awareness of key limitations and potential controversial issues still unaddressed will allow radiologists to accurately stage patients with lung cancer and optimize treatment decisions.

Prognostic effects of preoperative obstructive pneumonitis or atelectasis and comparison with tumor size in non-small cell lung cancer

BACKGROUND

In the eighth TNM staging system proposal, lung cancer with part or complete obstructive pneumonitis/atelectasis was classified to T2 category, and dividing lines of T category were changed. We conducted this study to search prognostic effect of preoperative obstructive pneumonitis/atelectasis and its comparison with tumor size.

METHODS

We collected clinical characteristics, preoperative hematological indicators, follow-up information of 1,313 lung cancer patients. Chi-square test was used to search relationship between obstruction pneumonitis/atelectasis and other factors. Kaplan-Meier (K-M) curves and cox regression methods were used for survival analysis.

RESULTS

Preoperative obstructive pneumonitis/atelectasis indicated shorter OS (HR: 1.308; 95% CI: 1.058-1.619) and RFS (HR: 1.276; 95% CI: 1.032-1.579) as an independent factor. In comparison with tumor size, we found patients with obstructive pneumonitis/atelectasis and T1 size tumor had similar prognosis to those with T2 size but without obstructive pneumonitis/atelectasis, and OS, RFS of patients with obstructive pneumonitis/atelectasis and T2 size were significantly shorter than those with T2 tumor size but without obstructive pneumonitis/atelectasis, while similar to patients with T3 tumor size but without obstructive pneumonitis/atelectasis according to division by the eighth edition. We also found obstructive pneumonitis/atelectasis was significantly related to higher neutrophil (P<0.001), platelet (P<0.001), monocyte (P<0.001), NLR (P<0.001), PLR (P=0.002), ESR (P<0.001) and lower LMR (P<0.001).

CONCLUSIONS

Preoperative obstructive pneumonitis/atelectasis predicted poor survival independently in non-small cell lung cancer (NSCLC). And we suggested which T staging group the patients with obstructive pneumonitis/atelectasis would be divided to should depend on tumor size in the eighth TNM staging system.

Lung Cancer Staging and Prognosis

The seventh edition of the non-small cell lung cancer (NSCLC) TNM staging system was developed by the International Association for the Staging of Lung Cancer (IASLC) Lung Cancer Staging Project by a coordinated international effort to develop data-derived TNM classifications with significant survival differences. Based on these TNM groupings, current 5-year survival estimates in NSLCC range from 73 % in stage IA disease to 13 % in stage IV disease. TNM stage remains the most important prognostic factor in predicting recurrence rates and survival times, followed by tumor histologic grade, and patient sex, age, and performance status. Molecular prognostication in lung cancer is an exploding area of research where interest has moved beyond TNM stage and into individualized genetic tumor analysis with immunohistochemistry, microarray, and mutation profiles. However, despite intense research efforts and countless publications, no molecular prognostic marker has been adopted into clinical use since most fail in subsequent cross-validation with few exceptions. The recent interest in immunotherapy for NSCLC has identified new biomarkers with early evidence that suggests that PD-L1 is a predictive marker of a good response to new immunotherapy drugs but a poor prognostic indicator of overall survival. Future prognostication of outcomes in NSCLC will likely be based on a combination of TNM stage and molecular tumor profiling and yield more precise, individualized survival estimates and treatment algorithms.

[New TNM classification of lung tumors]

The TNM classification of lung tumors has undergone many changes in the seventh edition published in 2010. These changes reflect current data and are based on the findings of the International Association for the Study of Lung Cancer (IASLC) from 81,495 patients and concern definitions of the T and M categories as well as stage grouping. They include a better description of regional lymph nodes of the lungs based on uniformly accepted definitions by the IASLC. The changes can lead to problems in the use of the definitions and will be discussed.

The seventh tumour-node-metastasis staging system for lung cancer: Sequel or prequel?

Anatomical cancer extent is an important predictor of prognosis and determines treatment choices. In non-small-cell lung cancer (NSCLC) the tumour–node–metastasis (TNM) classification developed by Pierre Denoix replaced in 1968 the Veterans Administration Lung cancer Group (VALG) classification, which was still in use for small-cell lung cancer (SCLC). Clifton Mountain suggested several improvements based on a database of mostly surgically treated United States (US) patients from a limited number of centres. This database was pivotal for a uniform reporting of lung cancer extent by the American Joint Committee of Cancer (AJCC) and the International Union against Cancer (IUCC), but it suffered increasingly from obsolete diagnostic and staging procedures and did not reflect new treatment modalities. Moreover, its findings were not externally validated in large Japanese and European databases, resulting in persisting controversies which could not be solved with the available database. The use of different mediastinal lymph-node maps in Japan, the (US) and Europe facilitated neither the exchange nor the comparison of treatment results.

Peter Goldstraw, a United Kingdom (UK) thoracic surgeon, started the process of updating the sixth version in 1996 and brought it to a good end 10 years later. His goals were to improve the TNM system in lung cancer by addressing the ongoing controversies, to validate the modifications and additional descriptors, to validate the TNM for use in staging SCLC and carcinoid tumours, to propose a new uniform lymph-node map and to investigate the prognostic value of non-anatomical factors. A staging committee was formed within the International Association for the Study of Lung Cancer (IASLC) – which supervised the collection of the retrospective data from >100,000 patients with lung cancer – treated throughout the world between 1990 and 2000, analyse them with the help of solid statistics and validate externally with the Surveillance, Epidemiology and End Results (SEER) database.

The ten modifications and the mediastinal lymph-node map – which were proposed in 2007 and adopted by the AJCC and IUCC in their respective seventh revision of the TNM system – were implemented as of 2010 and were rapidly adopted by the thoracic oncology community and cancer registries. As expected, not all controversies could be fully addressed, and the need for a prospective data set containing more granular information was felt early on. This data set of 25,000 consecutive incident cases will form the base for the eighth revision in 2017 and is currently being collected. Other threats are the role of stage migration and the increasing number of biological factors interfering with disease extent for prognostication. The latter issue will be addressed by the creation of a prognostic index, including several prognostic factors, of which stage will be one.

For the time being, the seventh TNM classification is considered the gold standard for the description of disease extent, initial treatment allocation and the reporting of treatment results. The uniform use of the TNM descriptors and the lymph-node map by all involved in lung cancer care is to be considered a process indicator of quality.

New TNM classification: achievements and hurdles

The 7th edition of TNM for Lung Cancer represented a major advance from previous editions, in the process of revision, the size and breadth of the data base used, its international character, the intensity of the analysis and the critical nature of the internal and external validation undertaken before its launch in January 2010. This all came about by the involvement of the International Association for the Study of Lung Cancer (IASLC), which assumed the role previously performed by Dr. Mountain, of developing data-driven revisions for the Union for International Cancer Control (UICC) and the American Joint Committee on Cancer (AJCC). In taking on this task the IASLC made the global lung cancer community aware of the limitations of previous revisions and now stand accountable and subject to the same scrutiny. In this article we describe the achievements of the IASLC TNM and Prognostic Factors Committee, but also the short-comings of the 7th edition, as an essential step towards rectifying deficiencies and further improving the classification in future revisions.

Extended resections of non-small cell lung cancers invading the aorta, pulmonary artery, left atrium, or esophagus: can they be justified?

T4 tumors that invade the heart, great vessels, or esophagus comprise a heterogenous group of locally invasive lung cancers. Prognosis depends on nodal status; this relationship has been consistently demonstrated in many of the small series of extended resection. Current National Comprehensive Cancer Network guidelines do not recommend surgery for T4 extension with N2-3 disease (stage IIIB). However, biopsy-proven T4 N0-1 (stage IIIA) may be operable. Localized tumors with invasion of the aorta, pulmonary artery, left atrium, or esophagus represent a small subset of T4 disease. Acquiring sufficient randomized data to provide statistical proof of a survival advantage for patients undergoing extended resections for these neoplasms will likely never be possible.Therefore, we are left to critically analyze current documented experience to make clinical decisions on a case-by-case basis.It is clear that the operative morbidity and mortality of extended resections for locally advanced T4 tumors have significantly improved over time,yet the risks are still high. The indications for such procedures and the anticipated outcomes should be clearly weighed in terms of potential perioperative complications and expertise of the surgical team. Patients with T4 N0-1 have the best prognosis and with complete resection may have the potential for cure. The use of induction therapy and surgery for advanced T4 tumors may improve survival. Current data suggest that for tumors that invade the aorta, pulmonary artery,left atrium, or esophagus, resection should be considered in relation to multidisciplinary care.For properly selected patients receiving treatment at high volume, experienced centers, extended resections may be warranted.

[Lymphatic spread of lung cancer: anatomical lymph node chains unchained in zones]

Lung cancer is characterized by its lymphophilia. Its metastatic spread mainly occurs by tumor cells lymphatic drainage into the blood circulation. Initially, the lymph node TNM classification was based on clinical and therapeutic considerations, particularly concerning N2 involvement. The goals were to avoid futile exploratory thoracotomies without lung resection, to provide more accurate data from mediastinoscopy, and to take into account the radiation therapy fields. Since 1997, the international lymph node classification was more used to analyse the disparities within N1 and N2 groups. However, this attempt did not succeed in clarifying the lymphatic metastazing process, and was not progressing any more. Anatomy not being considered, it did not permit to grasp the anatomical and physiological significances of N2 and N3 involvement. In effect, this classification is now confined in zones and is lacking the anatomical and physiological descriptions that characterise the lymphatic pathways draining the lungs and their tumoral pathology. The stations proposed in numbers in cartographies should have gained in accuracy and in prognostic value if they had been expressed in their anatomical counterparts.

Lung cancer staging: clinical and radiologic perspectives

Published in 2009, the 7th edition of the American Joint Committee on Cancer TNM staging system is the culmination of an extensive worldwide initiative to standardize and validate lung cancer staging. Unlike prior editions, the new staging system is now inclusive of small cell carcinoma and carcinoid tumors. In addition, significant changes were made to the T and M descriptors, resulting in improved prognostic stratification of disease. This review article highlights these changes, the rationale for their inclusion in the new staging manual, and the role of the radiologist in determining stage.

New staging system: how does it affect our practice?

The anatomic extent of disease, as described by the TNM classification, remains the most powerful prognostic indicator for lung cancer. It is used daily by specialists in all branches of lung cancer care and research. Any new edition of the TNM classification is therefore an important event in the thoracic oncology community and one greeted with mixed feelings. The changes introduced in the seventh edition were the first for 13 years and arguably the most profound since the first data-driven revision more than 40 years earlier. Inevitably there will be concerns that any change in the T, N, or M descriptors and resultant stage groupings will have implications for previous treatment pathways. In this article, the changes to the classification are described, and their possible impacts on clinical care and research are discussed.

A pooled exploratory analysis of the effect of tumor size and KRAS mutations on survival benefit from adjuvant platinum-based chemotherapy in node-negative non-small cell lung cancer

INTRODUCTION

The staging of node-negative non-small-cell lung cancer is modified in the 7th edition TNM classification. Here, we pool data from the National Cancer Institute of Canada Clinical Trials Group JBR.10 trial and the Cancer and Leukemia Group B-9633 trial to explore the prognostic and predictive effects of the new T-size descriptors and KRAS mutation status.

METHODS

Node-negative patients were reclassified as T2a (>3-≤5 cm), T2b (>5-≤7 cm), T3 (>7 cm) or T ≤ 3 cm (≤3 cm, but other T2 characteristics).

RESULTS

Of 538 eligible patients, 288 (53.5%) were T2a, 111 (21%) T2b, 62 (11.5%) T3, whereas 77 (14%) T≤3 cm were excluded to avoid confounding. KRAS mutations were detected in 104 of 390 patients (27%). T-size was prognostic for disease-free survival (p = 0.03), but borderline for overall survival (OS; p = 0.10), on multivariable analysis. Significant interaction between the prognostic value of KRAS and tumor size was observed for OS (p = 0.01), but not disease-free survival (p = 0.10). There was a nonsignificant trend (p = 0.24) for increased chemotherapy effect on OS with advancing T-size (hazard ratio [HR] T2a 0.90, [0.63-1.30]; T2b 0.69, [0.38-1.24]; and T3 0.57, [0.28-1.17]). The HR for chemotherapy effect on OS in T2a patients with KRAS wild-type tumors was 0.81 (p = 0.36), whereas a trend for detrimental effect was observed in those with mutant tumors (HR 2.11; p = 0.09; interaction p = 0.05). Similar trends were observed in T2b to T3 patients with wild-type (HR 0.86; p = 0.62), and KRAS mutant tumors (HR 1.16; p = 0.74; interaction p = 0.58).

CONCLUSION

Chemotherapy effect seems to increase with tumor size. However, this small study could not identify subgroups of patients who did or did not derive significant benefit from adjuvant chemotherapy based on T-size or KRAS status.

Updated staging system for lung cancer

The seventh edition of TNM for Lung Cancer came into effect on the first of January 2011. Containing more than 100,000 cases of lung cancer treated by all modalities of care and from around the world, this is the largest database ever accumulated for this purpose. This edition allows detailed analysis and intensive validation such that the resultant classification aligns stage with prognosis more closely than ever before. There have been changes to certain tumor and metastasis descriptors and the resultant stage groupings. This article describes these changes, provides more in-depth discussion of the changes, and provides much additional information.

Revisions to the TNM staging of non-small cell lung cancer: rationale, clinicoradiologic implications, and persistent limitations

The International Association for the Study of Lung Cancer proposed changes to the 7th edition of the Tumor, Node, and Metastasis (TNM) staging manual of non-small cell lung cancer (NSCLC) to improve the prognostic relevance of its descriptors. These changes include the subdivision of T1 and T2 disease according to size cut points; reassignment of the T and M categories of same-lobe, ipsilateral, and contralateral malignant pulmonary nodules; reassignment of pleural disease to metastatic disease; and introduction of intra- and extrathoracic metastatic disease. Because of movement between T and M descriptors and resultant stage migration, new stage groupings that contain TNM subsets different from those of the previous edition were created. The new staging classification was created on the basis of statistical analysis of a large international database of cases of NSCLC. The new classification has many advantages; however, limitations remain. Problems with routine radiologic staging of NSCLC have not been addressed, the varied survival rates for patients with the different histologic subtypes is not reflected, the new classification is not compatible with the previous system, and application of treatment algorithms on the basis of evidence from the previous edition is less clear.

Lung T-cell subset composition at the time of surgical resection is a prognostic indicator in non-small cell lung cancer

NSCLC arises in the complex environment of chronic inflammation. Depending on lung immune polarization, infiltrating immune cells may either promote or suppress tumor growth. Despite the importance of the immune microenvironment, current staging techniques for NSCLC do not take into consideration the immune milieu in which the neoplasms arise. T-cell subset content was compared between paired tumor-bearing and contralateral lungs, patient and control peripheral blood. The relationship between T-cell subset distribution and survival were evaluated. CD4 and CD8+ T cells were subsetted by CD45RA/CD27 and analyzed for expression of activation, adhesion, and homing markers. Strikingly, T-cell content was indistinguishable between lungs. Compared with peripheral blood, naïve CD4 and CD8 T cells were rare in BAL. CD4+ BAL T cells showed increased CD95 (higher apoptotic potential) and CD103 expression (epithelial adhesion), but decreased CD38 (activation) and CCR7 expression (lymph node homing). CD8+ BAL T cells showed increased CD103 expression and decreased CD28 expression (co-stimulation). Differences in CD28, CD95, and CCR7 expression were more pronounced within memory cells, while differences in CD4+ CD103 expression were more prominent in effector/memory cells. Of these populations, the absence of lung CD4 T cells with an effector-like phenotype (CD45RA+/CD27-) emerged as a predictor of favorable outcome. Patients with a low proportion (≤0.44%) had 90% 5-year survival (n = 10, median survival 2,343 days), compared with 0% (n = 9, median survival 516 days) of patients with a higher proportion. Further study is required to confirm this association prospectively and define the function of this subpopulation.

[New TNM classification of malignant lung tumors 2009 from a pathology perspective]

Based on the IASLC multicenter data collected worldwide on 81495 patients diagnosed or registered with lung cancer between 1990 and 2000, the T, N, and M descriptors were analyzed and recommendations for changes in the seventh edition of the TNM classification were proposed on the basis of differences in survival. This new TNM classification replaces the old UICC classification and the staging system according to C. Mountain 1997. The changes principally affect the T and M classifications. For the T component, tumor size was found to have prognostic relevance and its analysis led to recommendations to subclassify T1 into T1a and T1b, and T2 tumors into T2a and T2b and to reclassify T2 tumor>7 cm into T3 tumors. In the M category, M1 was recommended to be subclassified into M1a (contralateral lung nodules and pleural dissemination) and M1b (distant metastasis). There is no change in the N category. The proposed changes for the new stage grouping are to upstage T2b N0 M0 from stage IB to stage IIA and to downstage T2a N1 M0 from stage IIB to stage IIA and T4 N0-N1 M0 from stage IIIB to stage IIIA. The particulars of the new classification are discussed in the context of practice-relevant aspects from a pathology perspective view.

An update on lung cancer staging

The staging committee of the International Association for the Study of Lung Cancer has recently published, in collaboration with the International Union Against Cancer and the American Joint Committee on Cancer, the recommendations for the upcoming 7th edition of the tumor, node, metastasis classification and staging manual. This article reviews the changes in criteria for the tumor, node, metastasis components and discusses the issues that will be faced by pathologists when examining lung cancer specimens, including recommendations for tumor measurement, differentiation of multiple primary tumors versus metastases, and visceral pleural invasion.

The IASLC Lung Cancer Staging Project: proposals for the revision of the TNM stage groupings in the forthcoming (seventh) edition of the TNM Classification of malignant tumours

INTRODUCTION

The seventh edition of the TNM Classification of Malignant Tumors is due to be published early in 2009. In preparation for this, the International Association for the Study of Lung Cancer established its Lung Cancer Staging Project in 1998. The recommendations of this committee for changes to the T, N, and M descriptors have been published. This report contains the proposals for the new stage groupings.

METHODS

Data were contributed from 46 sources in more than 19 countries. Adequate data were available on 67,725 cases of non-small cell lung cancer treated by all modalities of care between 1990 and 2000. The recommendations for changes to the T, N, and M descriptors were incorporated into TNM subsets. Candidate stage groupings were developed on a training subset and tested in a validation subset.

RESULTS

The suggestions include additional cutoffs for tumor size, with tumors >7 cm moving from T2 to T3; reassigning the category given to additional pulmonary nodules in some locations; and reclassifying pleural effusion as an M descriptor. In addition, it is suggested that T2b N0 M0 cases be moved from stage IB to stage IIA, T2a N1 M0 cases from stage IIB to stage IIA, and T4 N0-1 M0 cases from stage IIIB to stage IIIA.

CONCLUSIONS

Such changes, if accepted, will involve a reassessment of existing treatment algorithms. However, they are based on an intensive and validated analysis of the largest database to date. The proposed changes would improve the alignment of TNM stage with prognosis and, in certain subsets, with treatment.

The IASLC Lung Cancer Staging Project: validation of the proposals for revision of the T, N, and M descriptors and consequent stage groupings in the forthcoming (seventh) edition of the TNM classification of malignant tumours

INTRODUCTION

In 1996, the International Association for the Study of Lung Cancer (IASLC) launched a worldwide TNM staging project to inform the next edition (seventh) of the TNM lung cancer staging system. In this article, we describe the methods and validation approaches used and discuss the internal and external validity of the recommended changes.

METHODS

The International Staging Committee agreed on a number of general principles that guided the decision-making process. Internal validity was addressed by visually assessing the consistency of Kaplan-Meier curves across database types, geographic regions and addressing external validity, by assessing the similarity of curves generated using the population-based Surveillance Epidemiology and End Results cancer registry data to those generated using the project database. Cox proportional hazards regression was used to calculate hazard ratios between the proposed stage groupings with adjustment for cell type, sex, age, and region.

RESULTS

Calls for data by the International Staging Committee resulted in the creation of an international database containing information on more than 100,000 cases. The present work is based on analyses of the 67,725 cases of non-small cell lung cancer. Validation checks were robust, demonstrating that the suggested staging changes are stable within the data sources used and externally. For example, suggested changes based on tumor size were well supported, with statistically significant hazard ratios ranging from 1.14 to 1.51 between adjacent pairs in the Surveillance Epidemiology and End Results data.

CONCLUSIONS

Lung cancer stage definitions have never been subjected to such an intense validation process. We do accept, however, that this work is limited in ways that can only be addressed by a prospective database, which we intend to develop. In the meantime, we think that this new system will greatly improve the usefulness of TNM lung staging across all of its purposes.

Prognostic significance of the non-size-based AJCC T2 descriptors: visceral pleura invasion, hilar atelectasis, or obstructive pneumonitis in stage IB non-small cell lung cancer is dependent on tumor size

BACKGROUND

The T2 descriptor for staging non-small cell lung cancer (NSCLC) contains several non-size-based criteria. It remains unknown whether the prognostic significance of these non-size-based criteria is dependent on tumor size.

METHODS

A total of 10,545 patients with stage IB NSCLC from the California Cancer Registry between 1989 to 2003 were categorized into the following three nonoverlapping criteria: (1) tumor size (T2S); (2) visceral pleura invasion, hilar atelectasis, or obstructive pneumonitis (T2P); and (3) main bronchus involvement > or = 2 cm from the carina (T2C). Univariate survival analyses were performed using the Kaplan-Meier method. Multivariate survival analyses were performed using Cox proportional hazards ratios.

RESULTS

A total of 51.1% of patients with stage IB NSCLC were staged by T2S, 43.2% by T2P, and 5.7% by T2C; 2,224 stage IB patients (total, 21.1%; 18.9% T2P + 2.2% T2C) had tumors < or = 3 cm in size. The 5-year survival rate and the median survival time of these stage IB patients with tumors < or = 3 cm in size were as follows: T2P, 51.2% and 64 months, respectively; T2C, 49.0% and 58 months, respectively. These values were similar to the 53.2% 5-year survival rate and 67-month median survival time for patients with stage IA NSCLC (p = 0.40). Cox proportional hazards model revealed T2P of > 3 cm was a poor prognostic factor for survival (vs T2S; hazard ratio [HR], 1.16; 95% confidence interval [CI], 1.08 to 1.24). Conversely, T2P < or = 3 cm was a favorable prognostic factor for survival (vs T2S; HR, 0.89; 95% CI, 0.82 to 0.96). T2C was not an independent prognostic factor for survival.

CONCLUSIONS

Prognostic significance of the non-size-based T2 descriptor T2P is dependent on tumor size.

[Historic landmarks in the study of lung cancer]

This study reviews the milestones which have been reached in the study of lung cancer, from its first early descriptions up until the end of the twentieth century. The study accompanies the birth of this new clinical entity, underlining the difficulties inherent in its diagnosis, its ever-growing increase and traces the growth of its aetiological factors, placing particular emphasis on smoking. In tandem with this, the study delves into the clinical aspects, along with new discoveries in imaging techniques and endoscopic and bioscopic techniques. It also looks at the histopathological classifications of bronchopulmonary tumours and the various staging systems which have been used over the course of time as well as the importance of mapping the disease and the different treatment weapons which have successively become available in the fight against it. The study also takes a look at the scales used in evaluating patients' physiological condition, the criteria used in evaluating response to oncostatic treatment and the role some international and national scientific societies and medical associations have played in adding to the increasing medical knowledge of lung cancer. The study clearly shows to whom we are indebted for each advance. This is a fascinating sweep of history - as is the story of all medical progress - and one we feel is important to understand, in order for us to see more clearly where we are now.

[Lung cancer and lymph drainage]

Lung cancer is lymphophile and may involve lymph nodes (LN) belonging to lung lymph drainage. LN metastases are figured within stations numbered 1 to 14. These stations are located along lymph vessels. The lymph vessels and the LN are forming together anatomical chains. Lymph vessels are valved and pulsatile and travel to the cervical venous confluence where they pour the lung lymph into the blood circulation. They may be totally or partly nodeless along their travel, anastomose with each other around the trachea, and connect with the thoracic duct within the mediastinum. Within the anatomical LN chains, LN are variable in number and in size from one individual to another. They may be absent from one or several stations of the international mapping. Stations are located along the anatomical chains: pulmonary ligament (9), tracheal bifurcation(8 and 7), right paratracheal (4R, 2R and 1), preaortic (5 and 6), left paratracheal (4L, 2L and 1). Station 3 is located on 2 differents chains (phrenic and right esophagotracheal). Station 10 are located at the beginning of the mediastinal lymph nodes chains. Each chain connects with the blood circulation, anastomoses with he neighbouring chains and behave as an own entity whatever the number of its LN. International station mapping misknowns this anatomy and occults the true pronostic value of lung lymph drainage.