Survival and characteristics of lymph node involvement in patients with N1 non-small cell lung cancer

Lymph Node Metastasis Prediction From In Situ Lung Squamous Cell Carcinoma Histopathology Images Using Deep Learning

Lung squamous cell carcinoma (LUSC), a subtype of non-small cell lung cancer, represents a significant portion of lung cancer cases with distinct histologic patterns impacting prognosis and treatment. The current pathological assessment methods face limitations such as interobserver variability, necessitating more reliable techniques. This study seeks to predict lymph node metastasis in LUSC using deep learning models applied to histopathology images of primary tumors, offering a more accurate and objective method for diagnosis and prognosis. Whole slide images (WSIs) from the Outdo-LUSC and the cancer genome atlas cohorts were used to train and validate deep learning models. Multiinstance learning was applied, with patch-level predictions aggregated into WSI-level outcomes. The study employed the ResNet-18 network, transfer learning, and rigorous data preprocessing. To represent WSI features, innovative techniques like patch likelihood histogram and bag of words were used, followed by training of machine learning classifiers, including the ExtraTrees algorithm. The diagnostic model for lymph node metastasis showed strong performance, particularly using the ExtraTrees algorithm, as demonstrated by receiver operating characteristic curves and gradient-weighted class activation mapping visualizations. The signature generated by the ExtraTrees algorithm, named lymph node status-related in situ LUSC histopathology (LN_ISLUSCH), achieved an area under the curve of 0.941 (95% CI: 0.926-0.955) in the training set and 0.788 (95% CI: 0.748-0.827) in the test set. Kaplan-Meier analyses confirmed that the LN_ISLUSCH model was a significant prognostic factor (P = .02). This study underscores the potential of artificial intelligence in enhancing diagnostic precision in pathology. The LN_ISLUSCH model stands out as a promising tool for predicting lymph node metastasis and prognosis in LUSC. Future studies should focus on larger and more diverse cohorts and explore the integration of additional omics data to further refine predictive accuracy and clinical utility.

Deep learning-based prediction of nodal metastasis in lung cancer using endobronchial ultrasound

Objective

Endobronchial ultrasound-guided transbronchial needle aspiration is a vital tool for mediastinal and hilar lymph node staging in patients with lung cancer. Despite its high diagnostic performance and safety, it has a limited negative predictive value. Our objective was to evaluate the diagnostic performance of deep learning-based prediction of lung cancer lymph node metastases using convolutional neural networks developed from automatically extracted images of endobronchial ultrasound videos without supervision of the lymph node location.

Methods

Patient and lymph node data were collected from a single-center database. The diagnosis of metastasis was confirmed with endobronchial ultrasound-guided transbronchial needle aspiration and/or surgically resected specimens; the diagnosis of normal lymph node was confirmed with surgically resected specimens only. An annotation system facilitated automated image extraction from endobronchial ultrasound videos. Image frames were randomly selected and split into training and validation datasets on a per-patient basis. A deep learning model with convolutional neural networks, SqueezeNet, was used for image classification via transfer learning based on pretraining from ImageNet. Adaptive moment estimation and stochastic gradient descent were applied as optimizers.

Results

SqueezeNet, with adaptive moment estimation, achieved a sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of 96.7% each after 300 epochs, whereas SqueezeNet with stochastic gradient descent achieved 91.1% each. However, SqueezeNet with stochastic gradient descent demonstrated more stable performance than with adaptive moment estimation.

Conclusions

Deep learning-based image classification using convolutional neural networks showed promising diagnostic accuracy for lung cancer nodal metastasis. Future clinical trials are warranted to validate the algorithm's efficacy in a prospective, large-cohort study.

A multi-kernel and multi-scale learning based deep ensemble model for predicting recurrence of non-small cell lung cancer

Predicting recurrence in patients with non-small cell lung cancer (NSCLC) before treatment is vital for guiding personalized medicine. Deep learning techniques have revolutionized the application of cancer informatics, including lung cancer time-to-event prediction. Most existing convolutional neural network (CNN) models are based on a single two-dimensional (2D) computational tomography (CT) image or three-dimensional (3D) CT volume. However, studies have shown that using multi-scale input and fusing multiple networks provide promising performance. This study proposes a deep learning-based ensemble network for recurrence prediction using a dataset of 530 patients with NSCLC. This network assembles 2D CNN models of various input slices, scales, and convolutional kernels, using a deep learning-based feature fusion model as an ensemble strategy. The proposed framework is uniquely designed to benefit from (i) multiple 2D in-plane slices to provide more information than a single central slice, (ii) multi-scale networks and multi-kernel networks to capture the local and peritumoral features, (iii) ensemble design to integrate features from various inputs and model architectures for final prediction. The ensemble of five 2D-CNN models, three slices, and two multi-kernel networks, using 5 × 5 and 6 × 6 convolutional kernels, achieved the best performance with an accuracy of 69.62%, area under the curve (AUC) of 72.5%, F1 score of 70.12%, and recall of 70.81%. Furthermore, the proposed method achieved competitive results compared with the 2D and 3D-CNN models for cancer outcome prediction in the benchmark studies. Our model is also a potential adjuvant treatment tool for identifying NSCLC patients with a high risk of recurrence.

The International Association for the Study of Lung Cancer Lung Cancer Staging Project: Overview of Challenges and Opportunities in Revising the Nodal Classification of Lung Cancer

The status of lymph node involvement is a major component of the TNM staging system. The N categories for lung cancer have remained unchanged since the fourth edition of the TNM staging system, partly because of differences in nodal mapping nomenclature, partly because of insufficient details to verify possible alternative approaches for staging. In preparation for the rigorous analysis of the International Association for the Study of Lung Cancer database necessary for the ninth edition TNM staging system, members of the N-Descriptors Subcommittee of the International Association for the Study of Lung Cancer Staging and Prognostic Factors Committee reviewed the evidence for alternative approaches to categorizing the extent of lymph node involvement with lung cancer, which is currently based solely on the anatomical location of lymph node metastasis. We reviewed the literature focusing on NSCLC to stimulate dialogue and mutual understanding among subcommittee members engaged in developing the ninth edition TNM staging system for lung cancer, which has been proposed for adoption by the American Joint Committee on Cancer and Union for International Cancer Control in 2024. The discussion of the range of possible revision options for the N categories, including the pros and cons of counting lymph nodes, lymph node stations, or lymph node zones, also provides transparency to the process, explaining why certain options may be discarded, others deferred for future consideration. Finally, we provide a preliminary discussion of the future directions that the N-Descriptors Subcommittee might consider for the 10th edition and beyond.

Peripheral Tumor Location Predicts a Favorable Prognosis in Patients with Resected Small Cell Lung Cancer

BACKGROUND

Small cell lung cancer (SCLC) is an aggressive malignancy. Surgical resection is currently only recommended for clinical stage I patients who have been carefully staged. The clinical outcomes of patients with resected SCLCs vary because the disease is highly heterogeneous, suggesting that selected patients could be considered for surgical resection depending on their clinical and/or molecular characteristics.

METHODS

We collected data on a retrospective cohort of 119 limited-stage SCLC patients who underwent lobectomy with mediastinal lymph node dissection from March 2013 to March 2020 at Harbin Medical University Cancer Hospital. Correlations were derived using Fisher's exact test. Models of 2-year and 3-year survival were evaluated by deriving the area under receiver operating characteristic curves. Kaplan-Meier and Cox regression analyses were used to evaluate significant differences between the survival curves and hazard ratios.

RESULTS

The median disease-free survival (DFS) was 35.9 months (range 0.9-105.3 months), and the median overall survival (OS) was 45.2 months (range 4.8-105.3 months). Univariate analysis showed that TNM stage was significantly correlated with DFS and OS. The 2-year disease-free rates of patients with stage I, II, and III disease were 76.4%, 50.5%, and 36.1%, respectively, and the 3-year OS rates were 75.9%, 57.7%, and 34.4%, respectively. In pN + patients, multiple (or multiple-station) lymph node involvement significantly increased recurrence and reduced survival compared with patients with single or single-station metastases. Patients with peripheral SCLCs evidenced significantly better DFS and OS than did patients with central tumors. Multivariate analysis showed that TNM stage and tumor location were independently prognostic in Chinese patients with resected limited-stage SCLC. A combination of TNM stage and tumor location was helpful for prognosis.

CONCLUSIONS

TNM stage and tumor location were independently prognostic in Chinese patients with resected SCLCs. Patient stratification by tumor location should inform the therapeutic strategy. The role of surgical resection for limited-stage SCLC patients must be reevaluated, as this may be appropriate for some patients.

Controversies in Mediastinal Staging for Nonsmall Cell Lung Cancer

Mediastinal lymph nodal involvement in nonsmall cell lung cancer plays a crucial role in deciding treatment strategy. Survival falls markedly with increasing involvement of mediastinal nodal stations. Hence, accurate staging of the mediastinum with lowest morbidity is of utmost importance. A wide array of invasive and noninvasive modalities that complement each other in assessing the nodes are available at our disposal. Guidelines recommend noninvasive imaging as the initial step in the staging algorithm for all tumors, followed by invasive staging. No single modality has proven to be the ideal method to stage the mediastinum when used alone. In the present decade, minimally invasive endobronchial ultrasound (EBUS) has challenged the position of surgical mediastinoscopy, which has been the gold standard, historically. However, a negative EBUS needs to be confirmed by surgical mediastinoscopy. Video-assisted mediastinoscopic lymphadenectomy has also come to the forefront in last two decades and has shown exceptional results, when performed in experienced centers. This review details the various modalities of mediastinal staging and the controversies surrounding the optimal method of staging, restaging after neoadjuvant therapy, and the most cost-effective strategy.

Minimizing residual occult nodal metastasis in NSCLC: recent advances, current status and controversies

Introduction: Nodal involvement in lung cancer is a significant determinant of prognosis and treatment management. New evidence exists regarding the management of occult lymph node metastasis and residual disease in the fields of imaging, mediastinal staging, and operative management.Areas covered: This review summarizes the latest body of knowledge on the identification and management of occult lymph node metastasis in NSCLC. We focus on tumor-specific characteristics; imaging modalities; invasive mediastinal staging; and operative management including, technique, degree of resection, and lymph node examination.Expert opinion: Newly identified risk-factors associated with nodal metastasis including tumor histology, location, radiologic features, and metabolic activity are not included in professional societal guidelines due to the heterogeneity of their reporting and uncertainty on how to adopt them into practice. Imaging as a sole diagnostic method is limited. We recommend confirmation with invasive mediastinal staging. EBUS-FNA is the best initial method, but adoption has not been uniform. The diagnostic algorithm is less certain for re-staging of mediastinal nodes after neoadjuvant therapy. Mediastinal node sampling during lobectomy remains the gold-standard, but evidence supports the use of minimally invasive techniques. More study is warranted regarding sublobar resection. No consensus exists regarding lymph node examination, but new evidence supports reexamination of current quality metrics.

Prognostic relevance of regional lymph-node distribution in patients with N1-positive non-small cell lung cancer: A retrospective single-center analysis

OBJECTIVE

Lymph node (LN) metastases predict survival in patients with non-small cell lung cancer (NSCLC) treated with curative surgery. Nevertheless, prognostic differences within the same nodal (N) status have been reported. Consequently, the International Association for the Study of Lung Cancer (IASLC) proposed to stratify patients with limited nodal disease (pN1) from low (pN1a) to high (pN1b) nodal tumor burden. This study aimed to validate the IASLC proposal in a large single-center surgical cohort of patients with pN1 NSCLC.

MATERIAL AND METHODS

Data from 317 patients with pN1 NSCLC treated between January 2012 and December 2016, were retrospectively analyzed. Associations between distribution of LN metastases and survival were analyzed for different classification models-toward nodal extension (pN1a: one station involved; pN1b: multiple stations involved) and toward location (pN1 in the hilar [LN#10/11] or peripheral zone [LN#12-14]).

RESULTS

Tumor-specific survival (TSS) in the entire pN1 cohort was 67.1% at five years. Five-year TSS rates for pN1a and pN1b patients were comparable (67.6% vs. 66.5%, p = 0.623). Significant survival differences from pN1a to pN1b were observed only in patients with adenocarcinoma histology and completed adjuvant chemotherapy (5-year TSS: pN1a, 80.4% vs. pN1b, 49.6%; p = 0.005). TSS for LN metastases in the hilar zone/peripheral zone or in both zones was 68.2% and 59.9%, respectively (p = 0.068). In multivariate analysis, adjuvant chemotherapy, squamous cell histology, and nodal disease limited to one zone nodal disease were identified as independent beneficial prognostic factors (p < 0.05).

CONCLUSION

pN1 in only one region (hilar or lobar) was associated with better outcome than metastatic affection of both regions after surgery and adjuvant therapy. A stratification towards single (pN1a) and multiple (pN1b) N1-metastases was found of prognostic relevance only in adenocarcinoma. Prospective multicenter analysis of prognostic subgroups in N1 NSCLC is required to evaluate its clinical impact for consideration in future TNM classification.

Prognostic Impact of the Number of Metastatic Lymph Nodes on the Eighth Edition of the TNM Classification of NSCLC

INTRODUCTION

Current nodal staging of NSCLC is defined only by anatomical location of lymph nodes (LNs). The aim of this study is to investigate prognostic impacts of the number of metastatic LNs by stratifying the present N classification.

METHODS

We analyzed 1989 patients with NSCLC who underwent complete resection by lobectomy or pneumonectomy involving dissection of the hilar and mediastinal LNs from 2003 to 2012. We classified patients according to the number of metastatic nodes and stations and their current category of metastatic LNs. We analyzed the overall survival in each group and assessed the survival impact of the combination of them.

RESULTS

In the multivariate analyses of all patients, pathological N1 (pN1) (reference [ref.] pN2) and single-node metastasis (ref. multiple-node) were independent prognostic factors whereas single-station metastasis (ref. multiple-station) was not. In the respective multivariate analyses of pN1 and pN2 disease, multiple-node metastasis (ref. single-node) was an independent prognostic factor in pN1 disease (hazard ratio: 1.41, p = 0.04), but not in pN2 disease. Investigation for other boundaries of a number of metastatic LNs of three or more (ref. one to two), four or more (ref. one to three), and five or more (ref. one to four) found that all of them were independent prognostic factors in both pN1 and pN2 diseases.

CONCLUSIONS

The number of metastatic LNs had a strong impact on survival in addition to the current pN classification. To clarify its prognostic impact, further study is needed in other datasets including patients treated by nonsurgical modalities.

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 and Predictive Effects of Positive Lymph Node Number or Ratio in NSCLC

In the eighth TNM staging system proposal for NSCLC recently, classification of N stage is based on anatomical position of positive lymph nodes. We aimed to expand the sample volume to identify the value of positive lymph node number or ratio in prognosis and predictive effect for postoperative radiation. Clinicopathological characters of 109026 NSCLC patients were collected from the SEER Database. Kaplan-Meier curves and cox regression methods were used for survival analysis. Compared with positive lymph node number equal to 0, 1–3 and >3 groups were independent prognostic factors (1–3: HR 2.856, p < 0.001; >3: HR 3.358, p < 0.001), so as the 0–50% and >50% positive lymph node ratio groups (0–50%: HR 2.124, p < 0.001; >50%: HR 3.358, p < 0.001). And in the groups of N2&positive lymph node number ≥4 and N2&positive lymph node ratio >50%, postoperative radiation related to positive prognosis of NSCLC patients. In conclusion, positive lymph node number or ratio was associated with survival as an independent indicator in NSCLC. They also had predictive effects for postoperative radiation, while N nodal stage not.

Prognostic factors in non-small cell lung cancer patients who received neoadjuvant therapy and curative resection

BACKGROUND

Lung cancer is the leading cause of cancer deaths in the world, and more and more treatment modalities have been introduced in order to improve patients' survival. For patients with advanced non-small cell lung cancer (NSCLC), survival prognosis is poor and multimodality neoadjuvant therapies are given to improve patients' survival. However, the possibility of occult metastases may lead to discrepancy between clinical and pathologic staging and underestimation of the disease severity. This discrepancy could be the reason for poor survival prediction reported by previous studies which conducted their analysis from the point of view of clinical stage. The aim of this study was to analyze the relationship between clinico-pathologic factors and survival from the pathologic point of view and to try to identify survival prognostic factors.

METHODS

From January 2005 to June 2011, 88 patients received neoadjuvant therapy because of initial locally advanced disease, followed by anatomic resection and mediastinal lymph node (LN) dissection. All their clinico-pathologic data were collected from a retrospective review of the medical records and subjected to further analysis.

RESULTS

We found that total metastatic LN ratio (P=0.01) and tumor size (P=0.02) were predictive factors for disease free survival (DFS). We used these two prognostic factors to stratify all patients into four groups. Group 4 (tumor size ≤5, total metastatic LN ratio ≤0.065) had the best DFS curve, while the DFS curve progressively deteriorated across group 3 (tumor size ≤5, total metastatic LN ratio >0.065), group 2 (tumor size >5, total metastatic LN ratio ≤0.065) and group 1 (tumor size >5, total metastatic LN ratio >0.065). However, no definitive prognostic factor could be identified in this study.

CONCLUSIONS

In conclusion, tumor size greater than 5 cm and total metastatic LN ratio greater than 0.065 could predict the DFS of patients with advanced NSCLC after multimodality therapies followed by surgical resection. Tumor size plays a more important role than total metastatic LN ratio in DFS. Moreover, patients identified with these factors need active post-operation surveillance and additional aggressive adjuvant therapies.

Prognostic value of metastatic N1 lymph node ratio and angiolymphatic invasion in patients with pathologic stage IIA non-small cell lung cancer

With regard to pathologic stage IIA (pIIA) non-small cell lung cancer (NSCLC), there is a paucity of literature evaluating the risk factors for disease-free survival (DFS) and overall survival (OS). The aim of this study was to identify the prognostic factors of DFS and OS in patients with NSCLC pIIA.We performed a retrospective review of 98 stage II patients (7th edition of the American Joint Committee on Cancer) who underwent lung resection from January 2005 to February 2011. Of these, 23 patients were excluded for this study because of loss of follow-up or different substage, and 75 patients with pIIA were included for further univariate and multivariate analysis. Risk factors for DFS and OS were analyzed, including age, gender, smoking history, operation method, histology, differential grade, visceral pleural invasion, angiolymphatic invasion, and metastatic N1 lymph node ratio (LNR).Of the 75 patients with pIIA NSCLC who were examined, 29 were female and 46 were male, with a mean age of 61.8 years (range: 34-83 years). The average tumor size was 3.188 cm (range: 1.10-6.0 cm). Under univariate analysis, angiolymphatic invasion and metastatic N1 LNR were risk factors for DFS (P = 0.011, P = 0.007). Under multivariate analysis, angiolymphatic invasion and metastatic N1 LNR were all independent risk factors for DFS, while adjuvant chemotherapy and higher metastatic N1 LNR were independent prognostic factors for OS.For patients with pIIA, higher metastatic N1 LNR and angiolymphatic invasion were related to poor DFS. In addition to DFS, higher metastatic N1 LNR was also a poor prognostic factor for OS rates and adjuvant therapy effectiveness. Clinical physicians should devise different postsurgical follow-up programs depending on these factors, especially for patients with high risk.

The impact of a novel lung gross dissection protocol on intrapulmonary lymph node retrieval from lung cancer resection specimens

Although thorough pathologic nodal staging provides the greatest prognostic information in patients with potentially curable non-small cell lung cancer, N1 nodal metastasis is frequently missed. We tested the impact of corrective intervention with a novel pathology gross dissection protocol on intrapulmonary lymph node retrieval. This study is a retrospective review of consecutive lobectomy, or greater, lung resection specimens over a period of 15 months before and 15 months after training pathologist's assistants on the novel dissection protocol. One hundred forty one specimens were examined before and 121 specimens after introduction of the novel dissection protocol. The median number of intrapulmonary lymph nodes retrieved increased from 2 to 5 (P<.0001), and the 75th to 100th percentile range of detected intrapulmonary lymph node metastasis increased from 0 to 5 to 0 to 17 (P=.0003). In multivariate analysis, the extent of resection, examination period (preintervention or postintervention), and pathologic N1 (vs N0) status were most strongly associated with a higher number of intrapulmonary lymph nodes examined. A novel pathology dissection protocol is a feasible and effective means of improving the retrieval of intrapulmonary lymph nodes for examination. Further studies to enhance dissemination and implementation of this novel pathology dissection protocol are warranted.

Prognostic significance of the extent of lymph node involvement in stage II-N1 non-small cell lung cancer

BACKGROUND

The non-small cell lung cancer (NSCLC) staging system (published in 2009 in the seventh edition of the cancer staging manuals of the Union for International Cancer Control and American Joint Commission on Cancer) did not include any changes to current N descriptors for NSCLC. However, the prognostic significance of the extent of lymph node (LN) involvement (including the LN zones involved [hilar/interlobar or peripheral], cancer-involved LN ratios [LNRs], and the number of involved LNs) remains unknown. The aim of this report is to evaluate the extent of LN involvement and other prognostic factors in predicting outcome after definitive surgery among Chinese patients with stage II-N1 NSCLC.

METHODS

We retrospectively reviewed the clinicopathologic characteristics of 206 patients with stage II (T1a-T2bN1M0) NSCLC who had undergone complete surgical resection at Shanghai Chest Hospital from June 1999 to June 2009. Overall survival (OS) and disease-free survival (DFS) were compared using Kaplan-Meier statistical analysis. Stratified and Cox regression analyses were used to evaluate the relationship between the LN involvement and survival.

RESULTS

Peripheral zone LN involvement, cancer-involved LNR, smaller tumor size, and squamous cell carcinoma were shown to be statistically significant indicators of higher OS and DFS by univariate analyses. Visceral pleural involvement was also shown to share a statistically significant relationship with DFS by univariate analyses. Multivariate analyses showed that tumor size and zone of LN involvement were significant predictors of OS.

CONCLUSIONS

Zone of N1 LN, LN ratios, and tumor size were found to provide independent prognostic information in patients with stage II NSCLC. This information may be used to stratify patients into groups by risk for recurrence.

Differential prognostic significance of extralobar and intralobar nodal metastases in patients with surgically resected stage II non-small cell lung cancer

OBJECTIVES

We sought to determine the prognostic significance of extralobar nodal metastases versus intralobar nodal metastases in patients with lung cancer and pathologic stage N1 disease.

METHODS

A retrospective review of a prospectively maintained lung resection database identified 230 patients with pathologic stage II, N1 non-small cell lung cancer from 1997 to 2011. The surgical pathology reports were reviewed to identify the involved N1 stations. The outcome variables included recurrence and death. Univariate and multivariate analyses were performed using the R statistical software package.

RESULTS

A total of 122 patients had extralobar nodal metastases (level 10 or 11); 108 patients were identified with intralobar nodal disease (levels 12-14). The median follow-up was 111 months. The baseline characteristics were similar in both groups. No significant differences were noted in the surgical approach, anatomic resections performed, or adjuvant therapy rates between the 2 groups. Overall, 80 patients developed recurrence during follow-up: 33 (30%) of 108 in the intralobar and 47 (38%) of 122 in the extralobar cohort. The median overall survival was 46.9 months for the intralobar cohort and 24.4 months for the extralobar cohort (P < .001). In a multivariate Cox proportional hazard model that included the presence of extralobar nodal disease, age, tumor size, tumor histologic type, and number of positive lymph nodes, extralobar nodal disease independently predicted both recurrence-free and overall survival (hazard ratio, 1.96; 95% confidence interval, 1.36-2.81; P = .001).

CONCLUSIONS

In patients who underwent surgical resection for stage II non-small cell lung cancer, the presence of extralobar nodal metastases at level 10 or 11 predicted significantly poorer outcomes than did nodal metastases at stations 12 to 14. This finding has prognostic importance and implications for adjuvant therapy and surveillance strategies for patients within the heterogeneous stage II (N1) category.

Risk factors for locoregional recurrence in patients with resected N1 non-small cell lung cancer: a retrospective study to identify patterns of failure and implications for adjuvant radiotherapy

Background

Meta-analysis of randomized trials has shown that postoperative radiotherapy (PORT) had a detrimental effect on overall survival (OS) in patients with resected N1 non–small cell lung cancer (NSCLC). Conversely, the locoregional recurrence (LR) rate is reported to be high without adjuvant PORT in these patients. We have evaluated the pattern of failure, actuarial risk and risk factors for LR in order to identify the subset of N1 NSCLC patients with the highest risk of LR. These patients could potentially benefit from PORT.

Methods

We conducted a retrospective study on 199 patients with pathologically confirmed T1–3N1M0 NSCLC who underwent surgery. None of the patients had positive surgical margins or received preoperative therapy or PORT. The median follow-up was 53.8 months. Complete mediastinal lymph node (MLN) dissection and examination was defined as ≥3 dissected and examined MLN stations; incomplete MLN dissection or examination (IMD) was defined as <3 dissected or examined MLN stations. The primary end point of this study was freedom from LR (FFLR). Differences between patient groups were compared and risk factors for LR were identified by univariate and multivariate analyses.

Results

LR was identified in 41 (20.6%) patients, distant metastasis (DM) was identified in 79 (39.7%) patients and concurrent LR and DM was identified in 25 (12.6%) patients. The 3- and 5-year OS rates in patients with resected N1 NSCLC were 78.4% and 65.6%, respectively. The corresponding FFLR rates were 80.8% and 77.3%, respectively. Univariate analyses identified that nonsmokers, ≤23 dissected lymph nodes, visceral pleural invasion and lymph node ratio >10% were significantly associated with lower FFLR rates (P < 0.05). Multivariate analyses further confirmed positive lymph nodes at station 10 and IMD as risk factors for LR (P < 0.05). The 5-year LR rate was highest in patients with both these risk factors (48%).

Conclusions

The incidence of LR in patients with surgically resected T1–3N1M0 NSCLC is high. Patients with IMD and positive lymph nodes at station 10 have the highest risk of LR, and may therefore benefit from adjuvant PORT. Further investigations of PORT in this subset of patients are warranted.

The role of segmental nodes in the pathological staging of non-small cell lung cancer

Background

Segmental nodes are not examined routinely in current clinical practice for lung cancer, the role of segmental nodes in pathological staging of non-small cell lung cancer after radical resection was investigated.

Methods

A total of 113 consecutive non-small cell lung cancer patients who underwent radical resection between June 2009 and December 2011 were retrospectively reviewed. All the operations were performed by the same group of surgeons. N2 nodes, hilar nodes, interlobar nodes and some lobar nodes were collected during surgery. The removed lung lobes were dissected routinely along lobar and segmental bronchi to collect lobar nodes and segmental nodes. The collected lymph nodes were separately labeled for histological examination.

Results

The detection rates of hilar nodes, interlobar nodes, lobar nodes and segmental nodes were 61.1%, 85.0%, 75.2% and 80.5%, respectively. The metastasis rates of hilar nodes, interlobar nodes, lobar nodes and segmental nodes were 5.3%, 10.5%, 16.8% and 14.2%, respectively. There were 68 cases of N0 disease, 16 cases of N1 disease and 29 cases of N2 disease. If an analysis of segmental lymph nodes had been omitted, six patients (37.5% of N1 disease) would have been down-staged to N0, and two cases of multiple-zone N1 disease would have been misdiagnosed as single-zone N1 disease, one patient would have been misdiagnosed as N2 disease with skip metastases.

Conclusion

Segmental nodes play an important role in the accurate staging of non-small cell lung cancer, and routinely dissecting the segmental bronchi to collect the lymph nodes is feasible and may be necessary.

The prognostic value of ratio-based lymph node staging in resected non-small-cell lung cancer

INTRODUCTION

Assessment of lymph node status is a critical issue in the surgical management of non-small-cell lung cancer (NSCLC). We sought to determine the prognostic value of metastatic lymph node ratio (LNR) in patients with radical surgery for NSCLC.

METHODS

We abstracted data from 480 consecutive patients undergoing radical surgery for NSCLC between 2006 and 2008 in our institution. Kaplan-Meier estimated the survival function using the number of metastatic lymph node (MLN) and LNR as categorized variables. The prognostic value of age, sex, smoking status, location of tumor, histology, pathology T stage, pathology N stage, surgical procedure, chemotherapy, MLN, and LNR were assessed using a multivariate Cox proportional hazards model for overall survival (OS) and disease-free survival (DFS).

RESULTS

The median numbers of examined lymph nodes and MLNs were 15 and 5, respectively. Optimal cutpoints of the LNR were calculated as 0, 0 to 0.35, and greater than 0.35. Patients with higher LNR were associated with worse OS and DFS in the whole series, whereas there was no significant difference in the OS and DFS of those patients classified as pathology N2. A multivariate analysis showed that the LNR staging, smoking status, and chemotherapy were revealed to be independent prognostic factors.

CONCLUSIONS

LNR is an independent predictor of survival in patients with NSCLC undergoing radical resection; the prognostic significance is more valuable in patients classified as pathology N1.

Vascular endothelial growth factor receptor-3 directly interacts with phosphatidylinositol 3-kinase to regulate lymphangiogenesis

Background

Dysfunctional lymphatic vessel formation has been implicated in a number of pathological conditions including cancer metastasis, lymphedema, and impaired wound healing. The vascular endothelial growth factor (VEGF) family is a major regulator of lymphatic endothelial cell (LEC) function and lymphangiogenesis. Indeed, dissemination of malignant cells into the regional lymph nodes, a common occurrence in many cancers, is stimulated by VEGF family members. This effect is generally considered to be mediated via VEGFR-2 and VEGFR-3. However, the role of specific receptors and their downstream signaling pathways is not well understood.

Methods and Results

Here we delineate the VEGF-C/VEGF receptor (VEGFR)-3 signaling pathway in LECs and show that VEGF-C induces activation of PI3K/Akt and MEK/Erk. Furthermore, activation of PI3K/Akt by VEGF-C/VEGFR-3 resulted in phosphorylation of P70S6K, eNOS, PLCγ1, and Erk1/2. Importantly, a direct interaction between PI3K and VEGFR-3 in LECs was demonstrated both in vitro and in clinical cancer specimens. This interaction was strongly associated with the presence of lymph node metastases in primary small cell carcinoma of the lung in clinical specimens. Blocking PI3K activity abolished VEGF-C-stimulated LEC tube formation and migration.

Conclusions

Our findings demonstrate that specific VEGFR-3 signaling pathways are activated in LECs by VEGF-C. The importance of PI3K in VEGF-C/VEGFR-3-mediated lymphangiogenesis provides a potential therapeutic target for the inhibition of lymphatic metastasis.

Validation of the lymph node ratio as a prognostic factor in patients with N1 nonsmall cell lung cancer

BACKGROUND

The number of positive lymph nodes (LNs) has been proposed as a prognostic indicator in N1 nonsmall cell lung cancer (NSCLC). However, the number of positive LNs is confounded by the number of LNs resected during surgery. The lymph node ratio (LNR) (the ratio of the number of positive LNs divided by the number of LNs resected) can circumvent this limitation. The prognostic significance of the LNR has been demonstrated in elderly patients with NSCLC. The objective of the current study was to evaluate whether a higher LNR is a marker of worse survival in patients with NSCLC aged ≤65 years who have N1 disease.

METHODS

The Surveillance, Epidemiology, and End Results database was used to identify 4004 patients who underwent resection for N1 NSCLC. Patients were classified into 3 groups according to LNR (≤0.15, 0.16-0.5, and >0.5). Associations of the LNR with lung cancer-specific and overall mortality were evaluated using the Kaplan-Meier method. Stratified and Cox regression analyses were used to assess correlations between the LNR and survival after adjusting for other prognostic factors.

RESULTS

Unadjusted analysis indicated that a higher LNR was associated with worse lung cancer-specific survival (P < .0001) and overall survival (P < .0001). Stratified and multivariate analyses also indicated that the LNR was an independent predictor of survival after controlling for potential confounders.

CONCLUSIONS

The current results confirmed that the LNR is an independent prognostic factor for survival in patients with N1 NSCLC. This information may be used to identify patients who are at greater risk of cancer recurrence.

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.

The number of lymph node metastases as a prognostic factor in patients with N1 non-small cell lung cancer

BACKGROUND

Lymph node (LN) status is an important component of staging; it provides valuable prognostic information and influences treatment decisions. However, the prognostic significance of the number of positive LNs in N1 non-small cell lung cancer (NSCLC) remains unclear. In this study we evaluated whether a higher number of positive LNs results in worse survival among patients with N1 disease.

METHODS

The Surveillance, Epidemiology, and End Results database was used to identify 3,399 patients who underwent resection for N1 NSCLC. Subjects were categorized into groups based on the number of positive nodes: one, two to three, four to eight, and more than eight positive LNs. The prognostic significance of the number of positive LNs in relation to survival was evaluated using the Kaplan-Meier method. Stratified and Cox regression analysis were used to evaluate the relationship between the number of positive LNs and survival after adjusting for potential confounders.

RESULTS

Unadjusted survival analysis showed that a greater number of N1 LNs was associated with worse lung cancer-specific (P < .0001) and overall (P < .0001) survival. Mean lung cancer-specific survival was 8.8, 8.2, 6.0, and 3.9 years for patients with one, two to three, four to eight, and more than eight positive LNs, respectively. Stratified and adjusted analysis also showed the number of N1 LNs was an independent predictor of survival after controlling for potential confounders.

CONCLUSION

The number of positive LNs is an independent prognostic factor of survival in patients with N1 NSCLC. This information may be used to further stratify patients with respect to risk of recurrence in order to determine postoperative management.

Lymph node ratio as a prognostic factor in elderly patients with pathological N1 non-small cell lung cancer

BACKGROUND

Lymph node (LN) metastasis is an important predictor of survival for patients with non-small cell lung cancer (NSCLC). However, the prognostic significance of the extent of LN involvement among patients with N1 disease remains unknown. A study was undertaken to evaluate whether involvement of a higher number of N1 LNs is associated with worse survival independent of known prognostic factors.

METHODS

Using the Surveillance, Epidemiology and End Results-Medicare database, 1682 resected patients with N1 NSCLC diagnosed between 1992 and 2005 were identified. As the number of positive LNs is confounded by the total number of LNs sampled, the cases were classified into three groups according to the ratio of positive to total number of LNs removed (LN ratio (LNR)): ≤0.15, 0.16-0.5 and >0.5. Lung cancer-specific and overall survival was compared between these groups using Kaplan-Meier curves. Stratified and Cox regression analyses were used to evaluate the relationship between the LNR and survival after adjusting for potential confounders.

RESULTS

Lung cancer-specific and overall survival was lower among patients with a high LNR (p<0.0001 for both comparisons). Median lung cancer-specific survival was 47 months, 37 months and 21 months for patients in the ≤0.15, 0.16-0.5 and >0.5 LNR groups, respectively. In stratified and adjusted analyses, a higher LNR was also associated with worse lung cancer-specific and overall survival.

CONCLUSIONS

The extent of LN involvement provides independent prognostic information in patients with N1 NSCLC. This information may be used to identify patients at high risk of recurrence who may benefit from aggressive postoperative therapy.

Relapse in resected lung cancer revisited: does intensified follow up really matter? A prospective study

Background

beside the well known predominance of distant vs. loco-regional relapse, several aspects of the relapse pattern still have not been fully elucidated.

Methods

prospective, controlled study on 88 patients operated for non-small cell lung cancer (NSCLC) in a 15 months period. Stage IIIA existed in 35(39.8%) patients, whilst stages IB, IIA and IIB existed in 10.2%, 4.5% and 45.5% patients respectively. Inclusion criteria: stage I-IIIA, complete resection, systematic lymphadenectomy with at least 6 lymph node groups examined, no neoadjuvant therapy, exact data of all aspects of relapse, exact data about the outcome of the treatment.

Results

postoperative lung cancer relapse occurred in 50(56.8%) patients. Locoregional, distant and both types of relapse occurred in 26%, 70% and 4% patients respectively. Postoperative cancer relapse occurred in 27/35(77.1%) pts. in the stage IIIA and in 21/40(52.55) pts in the stage IIB. In none of four pts. in the stage IIA cancer relapse occurred, unlike 22.22% pts. with relapse in the stage IB. The mean disease free interval in the analysed group was 34.38 ± 3.26 months.

The mean local relapse free and distant relapse free intervals were 55 ± 3.32 and 41.62 ± 3.47 months respectively Among 30 pts. with the relapse onset inside the first 12 month after the lung resection, in 20(66.6%) pts. either T3 tumours or N2 lesions existed. In patients with N0, N1 and N2 lesions, cancer relapse occurred in 30%, 55.6% and 70.8% patients respectively

Radiographic aspect T stage, N stage and extent of resection were found as significant in terms of survival. Related to the relapse occurrence, although radiographic aspect and extent of resection followed the same trend as in the survival analysis, only T stage and N stage were found as significant in the same sense as for survival. On multivariate, only T and N stage were found as significant in terms of survival.

Specific oncological treatment of relapse was possible in 27/50(54%) patients.

Conclusion

the intensified follow up did not increase either the proportion of patients detected with asymptomatic relapse or the number of patients with specific oncological treatment of relapse.

Prognostic significance of surgical-pathologic N1 lymph node involvement in non-small cell lung cancer

BACKGROUND

Patients with N1 non-small cell lung cancer represent a heterogeneous population with varying long-term survival. To better define the importance of N1 disease and its subgroups in non-small cell lung cancer staging, we analyzed patients with N1 disease using the sixth edition and proposed seventh edition TNM classifications.

METHODS

From January 1995 to November 2006, 540 patients with N1 non-small cell lung cancer who had at least lobectomy with systematic mediastinal lymphadenectomy were analyzed retrospectively.

RESULTS

For completely resected patients, the median survival rate and 5-year survival rate were 63 months and 50.3%, respectively. The 5-year survival rates for patients with hilar N1 (station 10), interlobar (station 11), and peripheral N1 (stations 12 to 14) involvement were 39%, 51%, and 53%, respectively. Patients with hilar lymph node metastasis showed a shorter survival period than patients with peripheral lymph node involvement (p = 0.02). Patients with hilar zone N1 (stations 10 and 11) involvement tended to show poorer survival than patients with peripheral zone N1 (12 to 14) metastasis (p = 0.08). Multiple-station lymph node metastasis indicated a poorer prognosis than single-station involvement (5-year survival 39% versus 51%, respectively, p = 0.01). Patients with multiple-zone N1 involvement showed poorer survival than patients with single-zone N1 metastasis (p = 0.04). A significant survival difference was observed between N1 patients with T1a versus T1b tumors (p = 0.02). Multivariate analysis revealed that only multiple-station lymph node metastasis was predictive of poor prognosis (p = 0.05).

CONCLUSIONS

Multiple-station versus single-station N1 disease and multiple-zone versus single-zone N1 involvement indicate poorer survival rate. Patients with hilar lymph node involvement had lower survival rates than patients with peripheral N1. The impact of T factor seemed to be veiled by the heterogenous nature of N1 disease. Further studies of adjusted postoperative strategies for different N1 subgroups are warranted.

The impact of multiple metastatic nodal stations on survival in patients with resectable N1 and N2 nonsmall-cell lung cancer

BACKGROUND

The aim of the study was to identify common prognostic factors in nonsmall-cell lung cancer (NSCLC) with N1 and N2 nodal involvement.

METHODS

A retrospective review of NSCLC patients who underwent primary surgical resection without neoadjuvant chemotherapy was performed. In all, 280 patients were included in this study, and there were 132 patients with N1 disease (N1 group) and 148 patients with N2 disease (N2 group). The median follow-up period was 26 months, and complete follow-up was possible in 269 patients (96%).

RESULTS

Lobectomy was performed in 194 patients (69%), bilobectomy was performed in 43 (15%), and pneumonectomy was performed in 43 (15%). Complete resection was possible in 273 patients (98%), and operative death occurred in 5 patients (2%). The overall and disease-free 5-year survival rates were 63% and 55%, respectively, in the N1 group, and 44% and 32%, respectively, in the N2 group (p < 0.05). The prognostic factors for overall survival in both the N1 and N2 groups were age and the number of metastatic nodal stations; however, N2 metastasis was not a significant prognostic factor in the multivariate analysis. The poor prognosis of the patients in the N2 group was due to the greater incidence of multiple node involvement in comparison with the N1 group (73% versus 15%; p < 0.05).

CONCLUSIONS

Multiple metastatic nodal stations was the common prognostic factor in resectable NSCLC patients with nodal metastasis, and mediastinal nodal involvement was associated with a higher chance of multiple-station metastasis in this study.

Prognostic Variability in Completely Resected pN1 Non-Small-Cell Lung Cancer

We used the Tuscan Cancer Registry archives to retrieve records of 2,896 patients with a histological diagnosis of lung tumor from January 1996 to December 2000. Of 2,410 patients with non-small-cell lung cancer, 767 (31.8%) underwent complete resection. The following variables were analyzed for their influence on survival in the 157 patients with pathologic N1 status: sex, age, cell type, pathologic tumor status, number and level of involved lymph nodes, tumor grade, and type of surgery. Overall 5-year survival rates were 43.9% for 417 patients with pN0 disease, 10.8% for 176 with pN2 disease, and 31.6% for those with pN1 disease. In pN1 disease, the overall 5-year survival rates for patients with hilar and non-hilar lymph node involvement were 27.4% and 39.6%, respectively. Univariate analysis demonstrated that pathological T status and level of N1 involvement weresignificant prognostic factors. Cox proportional hazards analysis indicated that hilar lymph node involvement was an independent prognostic factor. N1 lymph node status was identified as an independent prognostic factor in a combination of subgroups with different prognoses.

Prognostic value and therapeutic consequences of vascular invasion in non-small cell lung carcinoma

The prognostic relevance of blood vessel invasion (BVI) in non-small cell lung carcinoma (NSCLC) remains controversial, as is the question of whether its finding should influence therapeutic decisions after an R0 resection. One hundred and twelve cases of NSCLC were included in the study. All had been treated by potentially curative surgical resection of the primary tumor and systematic lymphadenectomy. In all cases, lymphatic metastatic spread was at its earliest stage and only one regional lymph node was involved, 27.0+/-8.9 nodes per patient being examined histologically. Most of the cases were pT2 (75.9%) and pN1 (81.3%), and all were MX/M0 and R0. 62.5% were at stage IIB, 25.9% at stage IIIA, and 9.8% at stage IIA. BVI was found in 45.5% of the tumors (V1), and 18.8% exhibited both lymphatic invasion and BVI (L1V1). Local recurrence occurred in 10.7% of the patients, distant metastasis in 24.1%, and both forms of tumor progression simultaneously in a further 7.1%. Thus 31.2% of the patients developed distant metastases by hematogenous spread (to the brain, bones, lung, adrenal, and liver, in descending order of frequency), mostly within two years of surgery. Late metastasis is not typical of NSCLC. Adenocarcinomas showed a strong tendency to be associated with a poorer prognosis than squamous cell carcinomas, probably because of their more frequent involvement of blood vessels. Five-year survival (Kaplan-Meier method) was significantly lower in V1 cases (37.2%) than in V0 cases (56.0%; p = 0.0249). Adjuvant mediastinal radiation in node-positive cases of NSCLC may prevent local recurrence but is unlikely to influence the development of distant metastases. The histological detection of BVI is of prognostic relevance and should be considered for inclusion in the staging criteria and indications for adjuvant chemotherapy.

The prognostic significance of multiple station N2 in patients with surgically resected stage IIIA N2 non-small cell lung cancer

Mediastinal (N2) lymph node involvement is heterogeneous with huge variation in the extent and grouped together under stage IIIA. However, they showed a different survival even in the same stage. We tried to determine the prognostic implication of the multiple station N2 lymph node metastasis in stage IIIA N2 non-small cell lung cancer (NSCLC). The survival of stage IIIA N2 was analyzed according to the number of N2 station and their survival was compared with that of stage IIIB. In stage IIIA N2 NSCLC, multivariate analysis indicated that multiple station N2 was one of the independent prognostic factors for poor survival. The 5-yr survival of multiple station N2 IIIA (20.4%) was lower than that of single station N2 IIIA (33.8%) significantly (p=0.016). but when it was compared with that of stage IIIB (15.5%), there was no difference. Therefore, we suggest that multiple station N2 should be considered similar to stage IIIB disease with regard to predicting survival and accordingly should receive a new position in the TNM staging system.

The prognostic value of carcinoembryonic antigen in T1N1M0 and T2N1M0 non-small cell carcinoma of the lung

OBJECTIVE

To evaluate the significance of preoperative clinicopathological factors, including serum carcinoembryonic antigen (CEA), as well as postoperative clinicopathological factors in T1-2N1M0 patients with non-small cell lung cancer who underwent curative pulmonary resection.

METHODS

Twenty T1N1M0 disease patients and 25 T2N1M0 patients underwent standard surgical procedures between September 1996 and December 2005, and were found to have non-small lung cancer. As prognostic factors, we retrospectively investigated age, sex, Brinkman index, histologic type, primary site, tumor diameter, clinical T factor, clinical N factor, pathological T factor, preoperative serum CEA levels, surgical procedure, visceral pleural involvement, and the status of lymph node involvement (level and number).

RESULTS

The overall 5-year survival rate of all patients was 59.6%. In univariate analysis, survival was related to age (<70/>or=70 years, p=0.0079), site (peripheral/central, p=0.043), and CEA level (<5.0/>or=5.0 ng/ml, p=0.0015). However, in multivariate analysis, CEA (<5.0/>or=5.0 ng/ml) was the only independent prognostic factor; the 5-year survival of the patients with an elevated serum CEA level (>or=5.0 ng/ml) was only 33.2% compared to 79.9% in patients with a lower serum CEA level (<5.0 ng/ml).

CONCLUSIONS

An elevated serum CEA level (>or=5.0 ng/ml) was an independent predictor of survival in pN1 patients except for T3 and T4 cases. Therefore, even in completely resected pN1 non-small cell lung cancer, patients with a high CEA level might be candidates for multimodal therapy.

Predictors of Survival and Disease-Free Survival in Patients With Resected N1 Non-Small Cell Lung Cancer

BACKGROUND

Factors that predict poor survival or increased risk of recurrence for patients with N1 disease may be dependent on tumor characteristics.

METHODS

This study was a retrospective review of a prospective database of consecutive patients who had clinical or pathologic N1 non-small cell lung cancer (NSCLC) who underwent preoperative 2-[18F] fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET) scans and complete resection with thoracic lymphadenectomy.

RESULTS

There were 135 patients (88 men). The 5-year disease-free rate was 55%. Kaplan-Meier analysis showed that poor differentiation (p = 0.036), multiple N1 stations (p = 0.010), and the lack of adjuvant chemotherapy (p = 0.039) were all associated with a shorter 5-year disease-free rate. Multivariate disease-free analysis demonstrated that only multiple stations (p = 0.002) were independently associated with recurrence. The overall 5-year survival was 48%. Univariate analysis showed that multiple nodes within one station (p = 0.016), multiple station involvement (p = 0.041), and lack of adjuvant chemotherapy (p = 0.039) and moderate-to-poor tumor differentiation (p = 0.046) were associated with decreased survival. Multivariate analysis found that multiple stations, multiple nodes, and lack of adjuvant chemotherapy were independent predictors of poor survival. Integrated PET-computed tomography (CT) was significantly more sensitive for staging N1 disease than dedicated FDG-PET (p = 0.032). Neoadjuvant chemotherapy given to 48 nonrandomized patients did not seem to impact disease recurrence or overall 5-year survival rates (p = 0.349).

CONCLUSIONS

Factors that predict a poor outcome in patients with resected N1 NSCLC are the involvement of multiple N1 stations, multiple N1 nodes, and the lack of adjuvant chemotherapy. Integrated PET-CT is more sensitive for detecting N1 disease then dedicated PET. These data may influence preoperative or postoperative therapy, or both.

Significance of extranodal extension of regional lymph nodes in surgically resected non-small cell lung cancer

STUDY OBJECTIVES

Regional lymph node (LN) involvement affects the prognosis of patients with surgically resected non-small cell lung cancer (NSCLC). The significance of extranodal extension in these groups of patients was prospectively studied to determine its clinicopathologic relationships and its influence on patient survival.

METHODS

A total of 199 NSCLC patients who were proved to have regional LN involvement after resection were included. Histologic examinations including tumor cell type, grade of differentiation, vascular invasion, regional LN metastasis emphasizing the number and station of LN involvement, the presence or absence of extranodal extension, and the immunohistochemistry of p53 expression were obtained. The relationships between extranodal extension and histologic type, grade of differentiation, vascular invasion, tumor size, pathologic stage, p53 expression, or patient survival were analyzed.

RESULTS

Extranodal extension was significantly higher in women, adenocarcinoma, advanced stage, tumors with vascular invasion, or p53 overexpression. The total number and positive rate of resected LNs with extranodal extension were significantly correlated with advanced stage, tumors with vascular invasion, or p53 overexpression. By multivariate analysis of survival, the presence or total number of LNs with extranodal extension, tumor stage, and p53 expression were significant prognostic factors. The 5-year survival rate of stage IIIA patients without extranodal extension (30.4%) was significantly better than that of stage II patients with extranodal extension (16.8%). No survival difference between extranodal positive stage II and IIIA patients was noted.

CONCLUSIONS

Extranodal extension of regional LNs is an important prognostic factor in patients with surgically resected NSCLC.

Completely resected N1 non–small cell lung cancer: Factors affecting recurrence and long-term survival

OBJECTIVE

N1 disease in non-small cell lung cancer represents a heterogeneous patient subgroup with a 5-year survival of approximately 40%. Few reports have evaluated the correlation between N1 disease and tumor recurrence or which subgroup of patients would most benefit from adjuvant chemotherapy.

METHODS

From 1997 through 2002, all patients with pathologic T1-4 N1 M0 non-small cell lung cancer who had a complete resection with systematic mediastinal lymphadenectomy were retrospectively analyzed and evaluated for factors associated with recurrence and long-term survival.

RESULTS

One hundred eighty patients with N1 disease were evaluated. Sixty-six (37%) patients had either locoregional recurrence (n = 39 [22%]), distant metastasis (n = 41 [23%]), or both during follow-up. Univariate analysis demonstrated that visceral pleural invasion and age were associated with locoregional recurrence, whereas visceral pleural invasion, distinct N1 metastasis (as opposed to direct N1 invasion by the primary tumor), and multistation lymph node involvement were associated with distant metastasis (P < .05). Multivariable analysis demonstrated that visceral pleural invasion, multistation N1 involvement, and distinct N1 metastasis were the only independent predisposing factors for locoregional recurrence and distant metastasis. Overall 5-year survival was 42.5%. Survival was significantly decreased by advanced pathologic T classification (P = .015), visceral pleural invasion (P < .0001), and higher tumor grade (P = .014).

CONCLUSIONS

In patients with N1-positive non-small cell lung cancer, visceral pleural invasion, multistation N1 disease, and distinct N1 metastasis are independent predictors of subsequent locoregional recurrence and distant metastasis. Advanced T classification, visceral pleural invasion, and higher tumor grade were predictors of poor survival. These patients represent a subgroup of patients with N1 disease who might benefit from additional therapy, including adjuvant chemotherapy.

Prognostic variability among nonsmall cell lung cancer patients with pathologic N1 lymph node involvement

BACKGROUND

Patients who have nonsmall cell lung cancer with N1 lymph node status are an intermediate group of patients who have a variable prognosis. Differences in lymph node level (hilar or pulmonary lymph nodes) may influence patient survival. The authors retrospectively analyzed the factors that influenced prognosis, including the level of N1 lymph node involvement.

METHODS

The authors used the Tuscan Cancer Registry archives to retrieve records on 2523 patients who had lung tumors diagnosed during the period from 1996 and 1998 in the provinces of Florence and Prato, central Italy. To analyze the survival of patients according to the level of lymph node involvement, the prognoses of patients with nonsmall cell lung cancer who had N1 lymph node status were compared in a population-based case series. Among 112 patients with pathologic N1 status, the following variables were analyzed for their influence on postoperative survival: gender, age, cell type, pathologic tumor status, the number of metastatic lymph nodes, the level of metastatic lymph nodes (hilar or pulmonary), and the type of surgical resection.

RESULTS

The 5-year survival rates for patients who had involvement of pulmonary and hilar lymph nodes were 41.2% and 21.8%, respectively (P =.005). A Cox proportional hazards model analysis indicated that the presence of hilar lymph node involvement was an independent prognostic factor.

CONCLUSIONS

N1 pathologic lymph node status was identified in a combination of subgroups with different prognoses, and the presence of hilar lymph node disease had prognostic significance. This difference in survival may lead to the use of different therapies for these subgroups of patients with pathologic N1 non-small cell lung cancer.

[T2N1M0 non-small cell lung cancer: surgery and prognostic factors]

OBJECTIVE

To determine the prognostic factors for the survival in a group of patients operated on for a non-small cell lung cancer classified as T2N1M0.

PATIENTS AND METHODS

Two hundred sixteen patients treated exclusively with surgery were studied. Kaplan-Meier survival and Cox multivariable regression analyses were used.

RESULTS

The overall survival rate was 39.8% at 5 years and 29.9% at 10 years. Sex, age, presence or absence of symptoms, type of resection, number, and location of affected lymph nodes had no effect on survival. Tumor size (P=.04) and histologic type (P=.03) did significantly affect prognosis. Both variables entered into the Cox multivariable regression model.

CONCLUSIONS

Patients operated on for non-small cell lung cancer classified as T2N1M0 have an overall probability of 5-year survival of approximately 40%. However, the prognosis for this group of patients is heterogeneous: in our study it was affected by the histologic type (45.5% for squamous cell and 25% for non-squamous cell cancers) and tumor size (53% for tumors with a diameter of <or=3 cm, 45% for tumors between 3.1 and 5 cm, and 29% for a tumor diameter >5 cm).

Prognosis of Stage II non-small cell lung cancer according to tumor and nodal status at diagnosis

PURPOSE

To evaluate the prognostic significance of tumor and node status among patients with Stage II non-small cell lung cancer using a population-based national database.

METHODS

We identified all primary cases of Stage II non-small cell lung cancer diagnosed prior to autopsy from the Surveillance, Epidemiology and End Results (SEER) registry. Lung cancer-specific survival curves were obtained for the 5254 patients who had curative surgical resection, stratifying for tumor and node status (T1-2N1M0, T3N0M0). The 12.5-year Kaplan-Meier estimator of survival was used as a measure of lung cancer cure rate. The influence of gender, age, cell type, pathologic tumor status, nodal metastasis, surgical method, and post-operative radiation therapy were evaluated using Cox regression.

RESULTS

Survival was better for T1N1 cases during the first 3--4 years after diagnosis. Five-year survival for T1N1 and T3N0 cases however, was not significantly different (46% versus 48%, p=0.4) and the cure rate was somewhat higher for T3N0 cases (33% versus to 27%, p=0.10). T2N1 cases had the worst overall survival. Multivariate analysis revealed that gender, age, tumor and nodal status, and histology were independent prognostic factors.

CONCLUSIONS

Among Stage II cancers, T3N0 cases have the highest cure rate and an overall survival pattern that more closely resembles T1N1 tumors. Several clinico-pathologic characteristics are significantly associated with survival and may explain some of the heterogeneity in outcomes among Stage II patients. These results suggest that T3N0 cases may be better classified as Stage IIA disease.