Completely resected stage IIIA non-small cell lung cancer: the significance of primary tumor location and N2 station

Distribution and characteristics of malignant tumours by lung lobe

BACKGROUND

The main focus on the characteristics of malignant lung tumours has been the size, position within the lobe, and infiltration into neighbouring structures. The aim of this study was to investigate the distribution and characteristics of malignant tumours between the lung lobes and whether the diagnosis, treatment, and outcome differed based on location.

METHODS

This study is based on 10,849 lung cancer patients diagnosed in 2018-2022 with complete data on the location and characteristics of the tumours. The proportions of tumours in each lobe divided by its volume were termed the relative proportion.

RESULTS

The right upper lobe comprised 31.2% of the tumours and 17.6% of the lung volume. The relative proportion of 1.77 was higher than in the other lobes (p < 0.001). The right middle lobe had a relative proportion of 0.64 but the highest proportion of neuroendocrine tumours (26.1% vs. 15.3 on average). Surgical resection was more often performed in patients with tumours in the lower lobes, and curative radiotherapy was more often performed in the upper lobes. After adjusting for age, sex, stage, and histology, the location of the tumour was found to be a significant independent predictor for resection but not for survival.

CONCLUSION

The main finding of the right upper lobe as a site of predilection for lung cancer is similar to tuberculosis and pneumoconiosis. This may be explained that most of the inhaled air, containing bacilli, inorganic particles or tobacco smoke goes to the upper and right parts of the lung.

Comparative analysis of methodologies for predicting overall survival in patients with non-small cell lung cancer based on the number and rate of resected positive lymph nodes: A study based on the SEER database for 2010 through 2019

BACKGROUND

Lymph node (LN) metastasis is crucial in non-small cell lung cancer (NSCLC) prognosis and treatment, but the TNM system lacks LN quantity consideration. Our goal is to investigate the role of positive LNs (nPLN) and positive LN rate (LNR) in overall survival (OS) and assess whether they offer higher value in prognostic assessment of NSCLC than N-stage.

METHODS

Patients were stratified into four subgroups using X-Tile software. Statistical analysis was conducted using the Kaplan-Meier method, univariate analysis, and multivariate Cox regression analysis. Model performance was evaluated using the Harrell consistency index (C-index), Akaike information criterion (AIC), and Bayesian information criterion (BIC). The prognostic performance of the nodal classification was validated using overall survival as the endpoint.

RESULTS

The survival curves demonstrate distinct disparities between each nPLN and LNR category. A pronounced trend toward deteriorating overall survival from N-PLN 1 to N-PLN 2+ was observed across all tumor size categories. However, the differences between each LNR category were only significant for tumors ≤3 cm and 5-7 cm. Notably, both nPLN and LNR classifications displayed a higher C-index, lower AIC, and lower BIC compared with the N staging. Furthermore, the LNR classification provided superior prognostic stratification when compared with the nPLN classification.

CONCLUSIONS

Our results demonstrate that nPLN and LNR classifications may offer improved prognostic performance compared with the current N classification for LN-positive NSCLC patients. Nonetheless, more studies are needed to assess the feasibility of incorporating these classifications into the next TNM staging system.

Impact of radiation on host immune system in patients treated with chemoradiotherapy and durvalumab consolidation for unresectable locally advanced non-small cell lung cancer

Background

The optimal modalities of radiotherapy when combining concurrent chemoradiation (CCRT) and immunotherapy (IO) for locally advanced non-small cell lung cancer (LA-NSCLC) remain to be determined. The aim of this study was to investigate the impact of radiation on different immune structures and immune cells in patients treated with CCRT followed by durvalumab.

Material and methods

Clinicopathologic data, pre- and post-treatment blood counts, and dosimetric data were collected in patients treated with CCRT and durvalumab consolidation for LA-NSCLC. Patients were divided into two groups according to the inclusion (NILN-R+) or not (NILN-R-) of at least one non-involved tumor-draining lymph node (NITDLN) in the clinical target volume (CTV). Progression-free survival (PFS) and overall survival (OS) were estimated by the Kaplan-Meier method.

Results

Fifty patients were included with a median follow-up of 23.2 months (95% CI 18.3-35.2). Two-year PFS and 2-year OS were 52.2% (95% CI 35.8-66.3) and 66.2% (95% CI 46.5-80.1), respectively. In univariable analysis, NILN-R+ (hazard ratio (HR) 2.60, p = 0.028), estimated dose of radiation to immune cells (EDRIC) >6.3 Gy (HR 3.19, p = 0.049), and lymphopenia ≤ 500/mm³ at IO initiation (HR 2.69, p = 0.021) were correlated with poorer PFS; lymphopenia ≤ 500/mm³ was also associated with poorer OS (HR 3.46, p = 0.024). In multivariable analysis, NILN-R+ was the strongest factor associated with PFS (HR 3.15, p = 0.017).

Conclusion

The inclusion of at least one NITDLN station within the CTV was an independent factor for poorer PFS in the context of CCRT and durvalumab for LA-NSCLC. The optimal sparing of immune structures might help in achieving better synergy between radiotherapy and immunotherapy in this indication.

[Bronchial carcinoma: metastatic pathways with involvement of hilar and mediastinal lymph nodes]

SIGNIFICANCE OF LUNG CANCER

Lung cancer has enormous socioeconomical impact on our society due to its high prevalence and mortality. About 59,700 new cases of lung cancer were forecasted for 2022.

TNM SCHEME FOR STAGING

Correct staging is the basis for therapy planning, prognosis estimation, and future analyses. Staging is performed using the TNM scheme from the Union for International Cancer Control (UICC). Involvement of lymph nodes is used to differentiate between stage IIB and IIIC.

LYMPH NODE LEVELS FOR LUNG CANCER

Knowledge of the intrathoracic lymph node levels is crucial for the exact classification and its involvement has direct implications on therapy. The International Association for the Study of Lung Cancer (IASLC) proposed a unified lymph node map with exact anatomic definitions, which is recommended by the German national lung cancer guideline. The extent of lymph node involvement is stratified into N0-N3. Different metastatic paths are known depending on the location of the primary tumor, but the burden of disease has a greater influence on survival, than the location of metastases.

ASSESSING THE SPREAD OF LUNG CANCER

Computed tomography can assess operability of the primary tumor safely in most cases. Invasive procedures to confirm the diagnosis by sampling tissue should be performed after noninvasive diagnostics.

PRACTICAL RECOMMENDATION

Systematic lymph node dissection for all patients with non-small cell lung cancer intended for curative resection is recommended in the current German national guideline for lung cancer.

Lobe-Specific Analysis of Sublobar Lung Resection for NSCLC Patients with Tumors ≤ 2 cm

Simple Summary

With the increase of the use of sublobar resection, the optimal strategy for early-stage NSCLC patients is essential. Previous studies showed tumors in different lobes are associated with different prognoses after radiotherapy and immunotherapy, inspiring us that each lobes had a different prognosis. Thus, we investigated the best surgical procedure for sublobar resection in patients with NSCLC ≤ 2 cm based on a lobe-specific analysis using propensity score matching. The results of this study will make it easier for surgeons to screen out patients with NSCLC ≤ 2 cm for segmentectomy or wedge resection, although this must be validated in larger cohorts.

Abstract

(1) Background: Sublobar resection can be used as an alternative surgical strategy for early-stage non-small-cell lung cancer (NSCLC) patients. However, the choice between wedge resection and segmentectomy remains contentious. In this study, we investigated the optimal surgical procedure for sublobar resection in patients with NSCLC ≤ 2 cm with a lobe-specific analysis; (2) Methods: Data for patients with T1N0M0 with a diameter of ≤2 cm who had undergone sublobar resection were retrieved. Propensity score matching (PSM) was used to reduce the inherent bias, and the Kaplan–Meier method and log-rank tests were used to assess the differences in survival; (3) Results: A total of 1882 patients were identified after the PSM. Patients with NSCLC ≤ 2 cm who had undergone segmentectomy showed better survival than those who had undergone wedge resection. However, when NSCLC was ≤1 cm, there was no significant difference in OS between the two groups. This demonstrated an OS advantage of segmentectomy over wedge resection for patients with NSCLC tumors of 1–2 cm (p = 0.024). Further analysis indicated that this survival benefit was only observed in patients with right upper NSCLC of 1–2 cm, but not with NSCLC in the other four lobes; (4) Conclusions: Segmentectomy showed a greater survival benefit than wedge resection only in patients with NSCLC of 1–2 cm, particularly those with primary tumors in the right upper lobe. Therefore, we propose a lobe-specific sublobar resection strategy for early-stage NSCLC patients (tumors of 1–2 cm) who cannot tolerate lobectomy.

Survival Analysis of Surgically Resected ypN2 Lung Cancer after Neoadjuvant Therapy

INTRODUCTION

 Surgery is widely accepted today when downstaging of mediastinal lymph nodes after neoadjuvant therapy is achieved. However, the role of surgery in patients with persistent N2 disease is still controversial. This study aims to detail the diagnostic problems, prognostic features, and long-term survival of the persistent N2 non-small cell lung cancer patient group.

PATIENTS AND METHODS

 One-hundred fifty patients who received neoadjuvant therapy and subsequently underwent resection, in-between 2003 and 2015, were retrospectively analyzed. In this study, "persistent N2" group refers to patients who received neoadjuvant therapy for clinically or histologically proven N2, who underwent a surgery after having been classified as "downstaged" at restaging, but in whom ypN2 lesions were subsequently confirmed on the operative specimens. Patients with multistation N2 were included in the study. There were 119 patients who met the criteria, whereas persistent ypN2 was detected in 28.5% (n = 34) of all patients.

RESULTS

 Overall 5-year survival rate was 47.2%, while it was 23.4% for patients with persistent N2. Factors that adversely affected survival were to have nonsquamous cell histological type (p = 0.006), high ypT stage (p = 0.001), persistent N2 (p = 0.02), and recurrence during follow-up (p < 0.001). A trend toward a shorter survival was observed when the ypN2 zone was subcarinal versus other zones, but did not reach statistical significance (p = 0.08). In addition, a trend toward a shorter survival of patients with multiple N2 involvement (p = 0.412) was observed.

CONCLUSION

 In the persistent N2 group, when multiple involvement or subcarinal involvement was excluded, relatively good survival was detected.

Primary tumor location in lung cancer: the evaluation and administration

ABSTRACT

Lung cancer continues to be the leading cause of cancer-related death in the world, which is classically subgrouped into two major histological types: Non-small cell lung cancer (NSCLC) (85% of patients) and small-cell lung cancer (SCLC) (15%). Tumor location has been reported to be associated with the prognosis of various solid tumors. Several types of cancer often occur in a specific region and are more prone to spread to predilection locations, including colorectal cancer, prostate cancer, gastric cancer, ovarian cancer, cervical cancer, bladder cancer, lung tumor, and so on. Besides, tumor location is also considered as a risk factor for lung neoplasm with chronic obstructive pulmonary disease/emphysema. Additionally, the primary lung cancer location is associated with specific lymph node metastasis. And the recent analysis has shown that the primary location may affect metastasis pattern in metastatic NSCLC based on a large population. Numerous studies have enrolled the "location" factor in the risk model. Anatomy location and lobe-specific location are both important in prognosis. Therefore, it is important for us to clarify the characteristics about tumor location according to various definitions. However, the inconsistent definitions about tumor location among different articles are controversial. It is also a significant guidance in multimode therapy in the present time. In this review, we mainly aim to provide a new insight about tumor location, including anatomy, clinicopathology, and prognosis in patients with lung neoplasm.

Quantification of the spatial distribution of primary tumors in the lung to develop new prognostic biomarkers for locally advanced NSCLC

The anatomical location and extent of primary lung tumors have shown prognostic value for overall survival (OS). However, its manual assessment is prone to interobserver variability. This study aims to use data driven identification of image characteristics for OS in locally advanced non-small cell lung cancer (NSCLC) patients. Five stage IIIA/IIIB NSCLC patient cohorts were retrospectively collected. Patients were treated either with radiochemotherapy (RCT): RCT1* (n = 107), RCT2 (n = 95), RCT3 (n = 37) or with surgery combined with radiotherapy or chemotherapy: S1* (n = 135), S2 (n = 55). Based on a deformable image registration (MIM Vista, 6.9.2.), an in-house developed software transferred each primary tumor to the CT scan of a reference patient while maintaining the original tumor shape. A frequency-weighted cumulative status map was created for both exploratory cohorts (indicated with an asterisk), where the spatial extent of the tumor was uni-labeled with 2 years OS. For the exploratory cohorts, a permutation test with random assignment of patient status was performed to identify regions with statistically significant worse OS, referred to as decreased survival areas (DSA). The minimal Euclidean distance between primary tumor to DSA was extracted from the independent cohorts (negative distance in case of overlap). To account for the tumor volume, the distance was scaled with the radius of the volume-equivalent sphere. For the S1 cohort, DSA were located at the right main bronchus whereas for the RCT1 cohort they further extended in cranio-caudal direction. In the independent cohorts, the model based on distance to DSA achieved performance: AUC_RCT2 [95% CI] = 0.67 [0.55–0.78] and AUC_RCT3 = 0.59 [0.39–0.79] for RCT patients, but showed bad performance for surgery cohort (AUC_S2 = 0.52 [0.30–0.74]). Shorter distance to DSA was associated with worse outcome (p = 0.0074). In conclusion, this explanatory analysis quantifies the value of primary tumor location for OS prediction based on cumulative status maps. Shorter distance of primary tumor to a high-risk region was associated with worse prognosis in the RCT cohort.

Significantly favourable outcome for patients with non-small-cell lung cancer stage IIIA/IIIB and single-station persistent N2 (skip or additionally N1) disease after multimodality treatment

OBJECTIVES

Persistent lymph nodes infiltration after neoadjuvant treatment remains a controversial topic in the treatment of stage III non-small-cell lung cancer (NSCLC). The aim of this study is to identify subgroups with persistent N2 disease, who could experience survival benefit from the addition of surgery.

METHODS

A retrospective mono-institutional study was conducted to analyse all patients with a final histopathology of NSCLC and persistent mediastinal disease after induction chemotherapy or chemoradiotherapy and surgery from January 1998 to June 2015.

RESULTS

A total of 145 patients (93 men, 52 women) fulfilled the inclusion criteria. The median age was 60 years (range 38-78). A total of 82 (56.5%) patients received a lobectomy, 48 (33.1%) a pneumonectomy, 11 (7.6%) a bilobectomy and 4 (2.6%) an anatomical segmentectomy; 128 (88.3%) were completely resected (R0). Operative mortality was 2.6% (4 patients), and morbidity was 35.2% (51 patients). Overall survival at 5 years was 47.3% (n = 19) for single N2 (skip), 30.2% (n = 16) for single N2 and N1 lymph nodes and under 5% (n = 1) for multiple mediastinal stations disease. Overall survival at 5 years after lobectomy/bilobectomy was not statistically different than after pneumonectomy (33.5% vs 20.5%, P = 0.082). Disease-free survival at 5 years was 30.6% (n = 6) for ypN2a1, 23.4% (n = 7) for ypN2a2 and under 5% (n = 1) for ypN2b status.

CONCLUSIONS

Lobectomy or bilobectomy has to be taken into account as a potentially curative option with promising long-term results for patients after induction treatment and persistent single-station N2 involvement (skip or additionally N1 status).

TRIAL REGISTRY NUMBER

14-6138-BO.

Correlation between tumor location and survival in stage I lung adenocarcinoma and squamous cell carcinoma: a SEER-based study

Background: Whether location mattered remained controversial in early-stage non-small cell lung cancer.

Methods: We conducted a retrospective study with the Surveillance, Epidemiology, and End Results (SEER) database. Overall survival (OS) and lung cancer-specific survival (LCSS) with landmark analysis and restricted mean survival time (RMST) were compared between patients with a tumor in upper lobe and non-upper lobe. The multivariable Cox analysis was applied to evaluate multiple prognostic factors.

Results: Tumor in non-upper lobe had worse OS (hazard ratio [HR]: 1.354, p < 0.001) and LCSS (HR: 1.476, p = 0.005) than the upper lobe in stage IB adenocarcinoma in 32-month landmark and IA3 (OS, HR: 1.300, p < 0.001; LCSS, HR: 1.413, p = 0.004) adenocarcinoma in 48-month landmark, but not in stage IA1 and IA2 adenocarcinoma. The results remained positive in subgroups of < 4, ≥ 4 and ≥ 11 LN examined in stage IB tumor and ≥ 4 LN examined in stage IA3 tumor. For SCC, non-upper lobar tumor had similar OS and LCSS with upper lobar tumor in all stages. The multivariate Cox analysis confirmed that the non-upper lobe was an independent risk factor in stage IA3-IB adenocarcinoma, but not in SCC. Adjuvant chemotherapy (ACT) could improve OS in stage IB adenocarcinoma (HR: 0.586, p < 0.001) and SCC (HR: 0.708, p = 0.030) located in non-upper lobe.

Conclusions: Non-upper lobar adenocarcinoma in stage IA3-IB was associated with worse prognosis. ACT may improve prognosis in stage IB tumor located in non-upper lobe.

Differential outcomes of residual disease in surgically-resected non-small cell lung cancer and the importance of guideline-concordant adjuvant therapy

Background

Positive mediastinal lymph nodes, a marker for systemic disease, and positive margins, a marker for local disease, following resection of non-small cell lung cancer (NSCLC) are forms of residual disease. The objective of this study is to compare survival of patients with residual disease and to study the effect of receipt of guideline vs. non-guideline concordant care.

Methods

The National Cancer Database (NCDB) was used to identify patients who underwent treatment naïve surgical resection with clinical stage T1-3N0-1M0 NSCLC between 2006–2016 and had pN2 disease, positive surgical margins, or both. Concordant care was determined based on form of chemotherapy and radiation, dosage, volume, modality, and duration. Kaplan-Meier survival curves and log-rank tests were used to compare five-year survival. Multivariable analysis using Cox proportional hazards modeling identified factors that contributed to worse overall survival.

Results

There were 8,189 patients included: pN2 (5,416), positive margins (2,386), and both (387). Five-year survival rates for all patients were pN2 (35.8%), positive margins (33.9%), and both (22.9%) (P<0.0001). On multivariable analysis, positive margins were an independent predictor of better survival relative to pN2 disease (HR =0.729, CI: 0.676, 0.787, P<0.0001). Receipt of non-guideline concordant treatment was an independent predictor of worse survival compared to receipt of guideline-concordant treatment (HR =1.61, CI: 1.504, 1.725, P<0.0001).

Conclusions

In upfront surgical patients, guideline-concordant treatment in the setting of residual disease is associated with better overall survival compared with non-guideline concordant treatment. Pathologic N2 disease is associated with a lower survival rate than positive resection margins, possibly reflecting the systemic nature of pN2 disease.

Alternative methods of lymph node staging in lung cancer: a narrative review

The nodal status indicator in non-small cell lung cancer is one of the most crucial prognostic factors available. However, there are still many arguments among scientists regarding whether the currently used nodal status descriptor should be changed in the forthcoming editions of the Tumor Node Metastasis classification or whether it is precise enough and should be maintained as is. We reviewed studies concerning nodal factor classifications to evaluate their accuracy in non-small cell lung cancer patients and to address the previously mentioned challenge. We reviewed the PubMed database regarding the following classifications: ongoing 8^th edition of the Tumor Node Metastasis classification, number of positive lymph nodes, number of negative lymph nodes, number of dissected lymph nodes, lymph node ratio, nodal chains, log odds of positive lymph nodes, zone-based classification and one that is based on the number of lymph node stations involved. Moreover, we analysed data regarding various combinations of these classifications. Our analysis showed that the present nodal staging may not accurately categorize every lung cancer patient. The number of positive lymph nodes and lymph node ratio or the log odds of positive lymph nodes (as the mathematical modification of lymph node ratio) are more legitimate, as they possess very robust data and should be considered initially as additional factors that can be incorporated in ongoing nodal staging systems. Forthcoming non-small cell lung cancer staging systems could benefit from the addition of quantitative-based parameters. Additionally, the minimal extent of lymphadenectomy should be established as staging benefits from it. International, prospective validation studies need to be performed to optimize the cut-off values and prognostic groups and to confirm the superiority of the newly suggested descriptors in non-small cell lung cancer nodal staging.

Lymph-node ratio predicts survival among the different stages of non-small-cell lung cancer: a multicentre analysis†

OBJECTIVES

The prognostic role of the number of resected and metastatic lymph nodes in non-small-cell lung cancer (NSCLC) is still being debated. The aim of this study was to evaluate the impact of lymphadenectomy in addition to the already validated variables in NSCLC survival.

METHODS

From January 2002 to December 2012, data on 4858 patients with NSCLC undergoing anatomical lung resection and hilomediastinal lymphadenectomy in 6 institutions were analysed retrospectively. Established prognostic factors in addition to the number of resected lymph nodes and the ratio between the number of metastatic lymph nodes and the number of resected lymph nodes (NR) were correlated to overall survival (OS) and disease-free survival (DFS) using the multivariable Cox regression model. Harrell's C-statistic with the 95% confidence interval (CI) was determined. Analysis by means of maximally selected log-rank statistics was performed to find optimal cut-off points in order to split patients into groups with different outcome probabilities.

RESULTS

The median numbers of resected lymph nodes and of metastatic lymph nodes were 17 (range 6-85) and 2 (1-36), respectively. Hilar (N1) and mediastinal (N2) metastases were identified in 21.3% and 20.0% of cases, respectively. Overall, the 5-year OS and DFS rates were 54.6% and 44.8%, respectively. At multivariable analysis, age, gender, pathological stage, R0 resection, type of surgery and NR correlated with longer OS rates; the same variables plus tumour grading were further related to DFS. C-statistics were 66.0 (95% CI 62.7-69.4) for DFS and 60.5 (95% CI 58.3-62.6) for OS. An NR <40% significantly correlated with a higher 5-year survival rate in the total sample (OS 57.6% vs 23.8%, P < 0.001; DFS 48.2% vs 11.4, P < 0.001) and in patients with N1 (OS 47.9% vs 36.1%, P = 0.03; DFS 39% vs 24.2%, P = 0.02) and N2 (OS 36.9% vs 21.8%, P < 0.001 DFS 23.9% vs 9.1%, P < 0.001).

CONCLUSIONS

Our study confirms that the number of resected lymph nodes is a strong prognostic indicator in NSCLC. In particular, an NR cut-off value of 40% may predict both OS and DFS.

Poor prognosis of NSCLC located in lower lobe is partly mediated by lower frequency of EGFR mutations

It is controversial whether a tumor located in the lower lobe is related with worse outcome of non-small cell lung cancer (NSCLC). This study aimed to clarify the prognostic role of primary tumor location in NSCLC. Patients newly diagnosed with NSCLC in a tertiary referral hospital from January 2011 to December 2014 were followed up for 5 years. Of the 2,289 NSCLC cases, 911 (39.8%) cases pertained to lower lobe cancers. Patients with lower lobe cancer showed a higher all-cause mortality rate than those with non-lower lobe cancer (48.6% vs. 40.3%, p < 0.001). Patients with lower lobe cancer had a lower proportion of adenocarcinoma histology and epidermal growth factor receptor (EGFR) mutations. Furthermore, compared to patients with non-lower lobe cancer, those with lower lobe cancer had a higher level of tumor markers (neuron-specific enolase and cytokeratin fragment 21-1). Mediation analysis revealed that the association between lower lobe cancer and higher all-cause mortality could be explained by an indirect pathway through EGFR mutations (percent mediated = 17.3%, p = 0.005). The sensitivity analysis for adenocarcinoma patients showed similar results (percent mediated = 18.8%, p = 0.021). Lower lobe cancer is associated with a higher all-cause mortality risk in patients with NSCLC, which is partly mediated by a lower proportion of EGFR mutations.

Resectable IIIA-N2 Non-Small-Cell Lung Cancer (NSCLC): In Search for the Proper Treatment

Locally advanced non-small cell lung cancer accounts for one third of non-small cell lung cancer (NSCLC) at the time of initial diagnosis and presents with a wide range of clinical and pathological heterogeneity. To date, the combined multimodality approach involving both local and systemic control is the gold standard for these patients, since occult distant micrometastatic disease should always be suspected. With the rapid increase in treatment options, the need for an interdisciplinary discussion involving oncologists, surgeons, radiation oncologists and radiologists has become essential. Surgery should be recommended to patients with non-bulky, discrete, or single-level N2 involvement and be included in the multimodality treatment. Resectable stage IIIA patients have been the subject of a number of clinical trials and retrospective analysis, discussing the efficiency and survival benefits on patients treated with the available therapeutic approaches. However, most of them have some limitations due to their retrospective nature, lack of exact pretreatment staging, and the involvement of heterogeneous populations leading to the awareness that each patient should undergo a tailored therapy in light of the nature of his tumor, its extension and his performance status.

Clinical Significance of Station 3A Lymph Node Dissection in Patients with Right-Side Non-Small-Cell Lung Cancer: A Retrospective Propensity-Matched Analysis

PURPOSE

To investigate the prognostic impact of station 3A lymph node (LN) dissection in patients with right-side non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

We retrospectively reviewed data of 1906 patients with primary right-side NSCLC who underwent lobectomy between January 2005 and December 2017 (570 patients underwent station 3A LN dissection and 1336 patients did not). Propensity score matching was conducted to minimize the effects of potential confounding factors. Disease-free survival (DFS) and overall survival (OS) were analyzed.

RESULTS

The metastasis rate of station 3A LN was 15.3% (87/570), which was second only to station 4 (17.3%). Only stations 10 and 11 LN metastases were found to be independent risk factors for station 3A LN metastasis (odds ratio = 19.43, 95% CI 1.21-311.12; P = 0.036 and odds ratio = 53.28, 95% CI 2.02-1404.90; P = 0.016, respectively). After propensity score matching, patients with dissection of station 3A LNs showed higher DFS (5-year DFS, 52.4% vs. 37.1%; P = 0.001) and OS (5-year OS, 58.8% vs. 48.7%; P = 0.007) than those without dissection. Subgroup analysis indicated that station 3A LN dissection was associated with significantly higher DFS and OS in patients with stage II and III disease. In multivariate survival analysis, dissection of 3A LNs retained its independent favorable effect on both DFS (hazard ratio = 0.76, 95% CI 0.64-0.90; P = 0.001) and OS (hazard ratio = 0.73, 95% CI 0.60-0.88; P = 0.001).

CONCLUSION

Station 3A LN involvement was not rare and station 3A LN dissection was associated with a more favorable prognosis in patients with right-side NSCLC.

Predictors of Distant Recurrence Following Stereotactic Body Radiation Therapy for Stage I Non-Small Cell Lung Cancer

OBJECTIVE

The objective of this study was to characterize patients at an increased risk of distant metastasis (DM) following stereotactic body radiation therapy (SBRT) for stage I non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

We identified patients undergoing SBRT for stage I NSCLC between 2005 and 2016. Patients with a prior lung cancer diagnosis, receiving a biological effective dose <100 Gy, or receiving chemotherapy were excluded. Patients underwent pretreatment staging and were classified according to the American Joint Committee for Cancer (AJCC) 8th edition staging. The primary endpoint was DM. The Kaplan-Meier method and the Cox proportional hazards model were used for survival analysis and to identify predictors of DM.

RESULTS

A total of 174 patients were included, with a median age 75 years (range, 49 to 96 y) and a median follow-up of 24 months (range, 3 to 123 mo). The 2- and 4-year cumulative incidences of DM were 14.2% and 19.1%, respectively. Patients who developed DM had worse overall survival versus patients developing a locoregional recurrence (P=0.023). On multivariable analysis, having stage IB disease (hazard ratio: 2.95; 95% confidence interval: 1.06-8.23; P=0.039) or a lower/middle lobe tumor (hazard ratio: 2.67; 95% confidence interval: 1.07-6.69; P=0.036) was associated with increased risk of DM. The 2-year cumulative incidences of DM were 10.9% and 35.7% (P=0.002) for patients with stage IA versus IB tumors, respectively, and 11.3% and 19.7% (P=0.049) for patients with upper lobe versus lower/middle lobe tumors, respectively.

CONCLUSIONS

Patients with stage IB disease or lower/middle lobe tumors may have an increased risk of DM following SBRT. Randomized controlled trials are needed to further identify patients who may benefit from adjuvant systemic therapy after SBRT for stage I NSCLC.

Postoperative Complications and Cancer Recurrence: Impact on Poor Prognosis of Lower Lobe Cancer

BACKGROUND

Previous reports suggest that lung cancer in the lower lobe is associated with a poorer prognosis than upper lobe disease. However, the reason remains controversial. We evaluated the relationship among the affected lobe, postoperative infectious complications, and cancer recurrence in patients who underwent lobectomy for clinical stage I lung cancer.

METHODS

We retrospectively reviewed 422 cases of resected lung cancer. We recorded the postoperative complications that developed within 30 days after surgery. The covariates included in the outcome analysis were patient demographic variables, surgical approach, laterality, affected lobe, tumor size, histologic type, tumor grade, pleural lavage cytology, pleural invasion, lymphovascular invasion, and lymph node metastasis.

RESULTS

Lower lobectomy was associated with significantly poorer recurrence-free (excluding nonspecific death) and overall survival than upper lobectomy. According to a stepwise multiple Cox proportional hazards analysis, lower lobectomy, lymph node metastasis, tumor grade, and pleural invasion were independent predictors of recurrence. The following postoperative complications were significantly associated with cancer recurrence and predominantly developed after lower lobectomy: any grade ≥3 complications (n = 61), space/organ surgical site infection of any grade (n = 55), and any infection requiring antibiotics (n = 61).

CONCLUSIONS

The current study revealed a significant relationship among the site of resection (upper or lower lobe), cancer recurrence, and occurrence of infectious complications. We must clarify the role of preventing infectious complications in improving the early- and long-term outcomes of lower lobe cancer.

Segment Location and Ground Glass Opacity Ratio Reliably Predict Node-Negative Status in Lung Cancer

BACKGROUND

Although selective mediastinal lymph node dissection based on lobe-specific nodal metastasis has been proposed for non-small cell lung cancer, controversy remains over its validity. We hypothesized that different segments within the same lobe might have different patterns of lymph node metastasis.

METHODS

Data on 2749 invasive non-small cell lung cancer patients who underwent pulmonary resection with systematic lymph node dissection from April 2008 to December 2015 were retrospectively analyzed. The segment location and consolidation tumor ratio were identified using preoperative computed tomography scans.

RESULTS

None of the 151 tumors with consolidation tumor ratio ≤ 0.5 had lymph node involvement. None of the 333 tumors located in apical segments had inferior mediastinal lymph node metastasis. When the analysis was limited to patients without hilar nodes involvement, only 7 out of 740 (0.9%) peripheral upper lobe tumors had inferior mediastinal lymph node metastasis. Interestingly, all these 7 tumors showed visceral pleural invasion. If hilar nodes were negative, superior mediastinal lymph node metastasis was not present for lower lobe ground glass opacity lesions. Among patients with left lower lobe tumors, if hilar nodes were negative, station 4L lymph node metastasis was not found in superior-segment or basal-segment tumors, and station 5/6 lymph node involvement was always absent in basal-segment tumors.

CONCLUSIONS

Segment location, ground glass opacity proportion, and absence of hilar lymph nodes involvement are reliable predictors of node-negative status in specific mediastinal regions. Based on these findings, we propose a new selective mediastinal lymph node dissection strategy for non-small cell lung cancer.

Single-station skip-N2 disease: good prognosis in resected non-small-cell lung cancer (long-term results in skip-N2 disease)

OBJECTIVES

Pathological N2 (pN2) involvement has a negative impact on prognosis in patients operated on due to non-small-cell lung cancer (NSCLC). pN2 disease may cause skip (pN0N2) or non-skip (pN1N2) metastases with pathological N1 (pN1) involvement. The effect of pN2 subgroups on prognosis is still controversial. We analysed the effect of pN1 disease and single-station pN2 disease subgroups on survival outcomes.

METHODS

The medical records of patients who underwent anatomical lung resection due to NSCLC at a single centre between January 2007 and January 2017 were prospectively collected and retrospectively analysed. Operative mortality, sublobar resection, Stage IV disease, incomplete resection and carcinoid tumour were considered exclusion criteria. After histopathological examination, the prognosis of patients with pN1, pN0N2 and pN1N2 was compared statistically. Univariable and multivariable analyses were made to define independent risk factors for overall survival rates.

RESULTS

The mean follow-up time for 358 patients with 228 pN1 disease (63.7%), 59 pN0N2 disease (16.5%) and 71 pN1N2 disease (19.8%) was 40.4 ± 30.4 months. Median and 5-year overall survival rates for pN1, pN0N2 and pN1N2 diseases were 73.6 months [95% confidence interval (CI) 55.5-91.7] and 54.1%, 60.3 months (95% CI 26.8-93.8) and 51.2%, 20.8 months (95% CI 16.1-25.5) and 21.5%, respectively. The survival CIs of pN1 and pN0N2 diseases were similar, and the survival rates of these 2 groups were significantly better than those with pN1N2 (P < 0.001, P = 0.001, respectively). In multivariable analysis, patients over the age of 60 [hazard ratio (HR) 2.13, P < 0.001], patients not receiving adjuvant therapy (HR 1.52, P = 0.01) and patients with pN1N2 disease (HR 2.91, P < 0.001) had a poor prognosis.

CONCLUSIONS

Advanced age, not receiving adjuvant therapy and having pN1N2 disease are negative prognostic factors in patients with nodal involvement who underwent curative resection due to NSCLC. The overall survival and recurrence-free survival rates of pN1 disease and single-station pN0N2 disease are similar, and they have significantly better survival rates than pN1N2 disease. Based on these results, surgical treatment may be considered an appropriate choice in patients with histopathologically diagnosed single-station skip-N2 disease.

Feasibility of nodal classification for non-small cell lung cancer by merging current N categories with the number of involved lymph node stations

Introduction

The aim of this study was to assess the prognoses of patients with non‐small cell lung cancer (NSCLC) according to the current nodal (N) categories of the tumor, node and metastasis (TNM) classification and the number of involved lymph node stations.

Methods

Five hundred and seventy patients with NSCLC underwent surgery from 1 January 2005 to 31 December 2009 and were analysed retrospectively. Postoperative overall survival was analysed according to two nodal classifications: the current N0, N1, N2 and N3 categories and those based on the number of involved nodal stations: N0, N1a (single N1), N1b (multiple N1), N2a1 (single N2 without N1), N2a2 (single N2 with N1), N2b1 (multiple N2 without N1) and N2b2 (multiple N2 with N1).

Results

Five‐year survival rates were 76.1%, 53.4% and 26.3% for N0, N1 and N2, respectively (P < 0.001). When survival was analysed by the number of involved nodal stations, the groups with significant differences were maintained; otherwise, they were merged, and new codes were assigned as follows for exploratory analyses: NA (N0), NB (N1a), NC (N1b, N2a (i.e., N2a1 and N2a2) and N2b1) and ND (N2b2). Five‐year survival rates were 76.1%, 60.0%, 39.1%, and 11.4% for NA, NB, NC and ND, respectively, and there were significant differences among them. This N classification was an independent prognostic factor in multivariate analyses.

Conclusion

Pending prospective and international validation, it is practical to merge the current N categories with the number of involved lymph node stations when evaluating the postoperative prognosis of NSCLC patients.

Proposal of a new nodal classification for operable non-small cell lung cancer based on the number of negative lymph nodes and the anatomical location of metastatic lymph nodes

Lymph node metastasis is one of the most important prognostic indicators in patients with radically resected non-small cell lung cancer (NSCLC). This retrospective study aimed to compare the predictive value of metastatic lymph nodes (MNs), lymph node ratio (LNR), resected lymph nodes (RNs), and negative lymph nodes (NNs) with the currently used pathologic nodal (pN) staging category.We conducted a retrospective analysis of 1019 consecutive NSCLC patients treated with complete resection in a single institution. Prognostic values of various lymph node factors were evaluated by analysis of univariate and multivariate Cox proportional hazards model, and the results were compared with those using the location-based pN stage classification.The median follow-up duration was 47 months. During this period, 353 cases of cancer recurrence and 337 deaths were reported. Multivariate cox analysis indicated that both pN and NN categories were independent predictors of patient survival. The patients were divided into six groups on the basis of pN and NN categories. The survival rates of the groups were as follows: pN0, NN≥8, 81.4%; pN0, NN<8, 73.8%; pN1, NN≥8, 61.4%; pN1, NN<8, 54.2%; pN2, NN≥8, 48.4%; and pN2>1, NN<8, 35.0%. Comparison of the predictive values of the lymph node factors showed that the new N category was a more valuable prognostic factor in operable NSCLC.The combination of anatomically based pN stage classification and the number of MNs is an accurate prognostic determinant in patients with operable NSCLC which can be equal to 8th N category.

Prediction of lymph node status in completely resected IIIa/N2 small cell lung cancer: importance of subcarinal station metastases

Background

The aim of this study was to determine the prognostic value of lymph node status in patients with pathologic N2 (pN2) stage IIIA small cell lung cancer (SCLC).

Methods

A total of 163 consecutive pN2 stage IIIA SCLC patients who underwent pulmonary resections and systematic lymphadenectomies at Shanghai Chest Hospital between January 2006 and June 2014 were enrolled. We retrospectively analyzed the potential clinicopathologic factors that influenced survival, including the node levels (single or multiple-station) and the node-spreading patterns (skip N2 or non-skip N2). The prognostic significance was examined by Cox regression analysis.

Results

The median overall survival (OS) was 23.7 months. Multiple-station lymph node metastasis indicated a poorer prognosis than single-station involvement (p = 0.003). Skip metastasis did not appear to influence survival (p = 0.099). With respect to the station of lymph node metastasis, the OS was only related to the involvement of the subcarinal node, regardless of tumor location (p < 0.05). Multivariate analysis showed two statistically significant risk factors for survival, including multiple-station lymph node and subcarinal node metastasis (hazard ratio [HR] = 1.76, 95% confidence interval [CI]:1.11–2.78, p = 0.015; HR = 1.61, 95% CI: 1.03–2.50, p = 0.036, respectively).

Conclusions

Multiple-station N2 metastasis and involvement of the subcarinal node predicted poor prognosis in pN2 stage IIIA SCLC patients, which may profoundly influence therapeutic decisions.

Location of stage I-III non-small cell lung cancer and survival rate: Systematic review and meta-analysis

BACKGROUND

The association between the location of non-small cell lung cancer (NSCLC) and prognosis is a debated issue. Some studies have provided evidence of better prognosis of upper lobe tumors than lower to middle lobe tumors, while other studies have reported contrasting conclusions. The aim of this study was to further assess this association through a systematic review and meta-analysis.

METHODS

Medline, Embase, and the Cochrane Central Register of Controlled Trials were searched up to 27 January 2017. Patients pathologically diagnosed with stage I-III NSCLC with three or five-year survival data were included. The main meta-analysis compared differences in survival rates according to the primary tumor location using the Mantel-Haenszel method with a random effect model. Sensitivity analysis was conducted according to lymph node metastasis, tumor node metastasis stage, staging method, and treatment modality.

RESULTS

Ten clinical studies and 35 570 patients were recruited. Patients with tumors in the upper lobes had a higher rate of five-year survival compared to those with tumors in non-upper lobes (odds ratio [OR] 1.31, 95% confidence interval [CI] 1.15-1.49). Similarly, the three-year survival rate was high in patients with tumors in the upper lobes (OR 1.99, 95% CI 1.02-3.86) and low in those with lower lobe tumors (OR 0.31, 95% CI 0.12-0.77).

CONCLUSIONS

Stage I-III NSCLC located in the upper lobes showed higher five-year survival rates compared to other tumor locations.

Multimodality Therapy for N2 Non-Small Cell Lung Cancer: An Evolving Paradigm

BACKGROUND

Induction chemoradiation for resectable N2 non-small cell lung cancer (NSCLC) is used with the intent to optimize locoregional control, whereas induction chemotherapy given in systemic doses is meant to optimally target potential distant disease. However, the optimal preoperative treatment regimen is still unknown and practice patterns continue to vary widely. We compared multiinstitutional oncologic outcomes for N2 NSCLC from 4 experienced lung cancer treatment centers.

METHODS

This collaborative retrospective study unites 4 major thoracic oncology centers. Patients with N2 NSCLC undergoing surgical resection after induction chemotherapy (CxT) or concurrent chemoradiation (CxRT) were included. Primary outcomes were overall and disease-free survival (OS and DFS).

RESULTS

822 patients were identified (CxT = 662 and CxRT = 160). There were no differences in 5-year OS (CxT 39.9% versus CxRT 42.9%, p = 0.250) nor in DFS (CxT 28.7% versus 29.8%, p = 0.207). Recurrence rates (CxT 46.8% versus CxRT 51.6%, p = 0.282) and recurrence patterns were not significantly different (Local: CxT 9.8% versus CxRT 9.7%; and Distant: CxT 30.4% versus CxRT 33.1%, p = 0.764). There was no difference in perioperative mortality. In the analyses of patients who underwent pretreatment invasive mediastinal staging (n = 555), there were still no significant differences in OS (p = 0.341) and DFS (p = 0.455) between the 2 treatment strategies.

CONCLUSIONS

Both treatment strategies produce equivalent and better than expected outcomes compared with historical controls for N2 NSCLC, with no differences in recurrence patterns. How these conventional therapeutic strategies will compare with those involving immunotherapy combined with surgical locoregional disease control for N2 disease remains to be determined.

Lung cancer staging: a concise update

Diagnosis and clinical staging of lung cancer are fundamental to planning therapy. The techniques for clinical staging, i.e anatomic and metabolic imaging, endoscopies and minimally invasive surgical procedures, should be performed sequentially and with an increasing degree of invasiveness. Intraoperative staging, assessing the magnitude of the primary tumour, the involved structures, and the loco-regional lymphatic spread by means of systematic nodal dissection, is essential in order to achieve a complete resection. In resected tumours, pathological staging, with the systematic study of the resected specimens, is the strongest prognostic indicator and is essential to make further decisions on therapy. In the present decade, the guidelines on lung cancer staging of the American College of Chest Physicians and the European Society of Thoracic Surgeons are based on the best available evidence and are widely followed. Recent advances in the classification of the adenocarcinoma of the lung, with the definition of adenocarcinoma in situ, minimally invasive adenocarcinoma and lepidic predominant adenocarcinoma, and the publication of the eighth edition of the tumour, node and metastasis classification of lung cancer, have to be integrated into the staging process. The present review complements the latest guidelines on lung cancer staging by providing an update of all these issues.

Lymph node ratio as a prognostic factor in patients with pathological N2 non-small cell lung cancer

BACKGROUND

The aim of this study was to investigate whether the lymph node ratio (LNR) was associated with the prognosis of patients, who underwent surgery for pathological N2 non-small cell lung cancer (NSCLC).

METHODS

A total of 182 patients were diagnosed with pathological N2 disease and underwent complete resection surgeries with systematic lymphadenectomies. We counted the number of positives and removed lymph nodes to calculate a ratio between them (LNR). We also investigated the association between skip mediastinal lymph node metastasis and survival.

RESULTS

Univariate analysis of survival in patients with N2 NSCLC showed that the T factor, clinical N factor, and LNR were significant prognostic factors. Multivariate analyses showed that the clinical N stage and LNR were significant independent prognostic factors for patients with pathological N2 NSCLC. Patients with a clinical lymph node status of 0 (cN0) and LNR ≤0.22 showed a significantly higher survival rate than patients with a cN1-2 and LNR ≥0.22 and 5-year survival rates were 47.1 and 10.3%, respectively (p < 0.0001).

CONCLUSIONS

LNR is an important prognostic factor for poor outcome following surgery in patients with N2 disease. The combination of the LNR and cN status provides a valuable prognostic tool.

Epidermal Growth Factor Receptor Mutations and Prognosis in Pathologic N1-N2 Pulmonary Adenocarcinoma

BACKGROUND

Advanced unresectable pulmonary adenocarcinoma with the epidermal growth factor receptor (EGFR) exon 21 L858R point mutation (Ex21) is associated with a poor prognosis. However, for early-stage resectable adenocarcinoma, Ex21 tumors have a lower-grade malignancy than exon 19 deleted (Ex19) tumors. We therefore investigated the effect of EGFR mutations on the prognosis in patients with completely resected pN1-N2 adenocarcinoma.

METHODS

Five-year disease-free survival (DFS) and overall survival (OS) were analyzed in 202 pN1-N2 pulmonary adenocarcinoma patients, 100 of whom had EGFR mutations, comprising Ex21 in 41 (20.3%), Ex19 in 55 (27.2%), and Ex18 in 4 (2%).

RESULTS

Patients with and without EGFR mutations had similar DFS (26.2% vs 24.6%, respectively; p = 0.280) and OS (64.9% vs 54.2%, respectively; p = 0.564). Patients with Ex19 tumors had significantly better DFS (38.8% vs 11.8%, p = 0.001) and tended to have better OS (78.3% vs 48.3%, p = 0.123) than those with Ex21 tumors. For pN1, patients with Ex19 tumors had a longer disease-free interval (54.0 vs 22.3 months, p = 0.003) and median survival time (81.0 vs 50.6 months, p = 0.022) than those with Ex21 tumors. For pN2, patients with Ex19 tumors had longer disease-free interval than those with Ex21 tumors (43.6 vs 30.1 months, p = 0.109). Multivariate analysis showed Ex21 was a prognosticator of poor DFS (hazard ratio, 2.25; 95% confidence interval, 1.21 to 4.20).

CONCLUSIONS

For pN1-N2 pulmonary adenocarcinoma, Ex21 mutation was associated with poorer prognosis than Ex19 mutation. Thus, EGFR mutation status should be considered when predicting prognosis.

[Advances in Lymph Node Metastasis and the Modes of Lymph Node Dissection in Early Stage Non-small Cell Lung Caner]

目前，肺癌已是全球范围内发病率及死亡率最高的恶性肿瘤，非小细胞肺癌（non-small cell lung cancer, NSCLC）约占肺癌80%。手术治疗在早期NSCLC治疗中占主导地位，而淋巴结分期及手术中清扫程度直接影响着患者术后生活质量及患者的预后。解剖性肺叶切除加系统性淋巴结清扫一直以来被认为是NSCLC的标准手术方式，但对早期NSCLC患者纵隔淋巴结清扫程度问题上一直存在较大争议，精确评估区域淋巴结的转移及淋巴结清扫的程度是影响患者围手术期并发症和预后的重要因素。对于早期肺癌行肺叶特异性或选择性淋巴结清扫已逐渐为国内外学者接受，并可能成为临床Ⅰ期NSCLC患者标准淋巴结清扫方式。

Impact of patient selection and treatment strategies on outcomes after lobectomy for biopsy-proven stage IIIA pN2 non-small cell lung cancer

OBJECTIVES

We evaluated the impact of patient selection and treatment strategies on long-term outcomes of patients who had lobectomy after induction therapy for stage IIIA pN2 non-small cell lung cancer (NSCLC).

METHODS

The impact of various patient selection, induction therapy and operative strategies on survival of patients with biopsy-proven stage IIIA pN2 NSCLC who received induction chemotherapy ± radiation followed by lobectomy from 1995 to 2012 was assessed using Cox proportional hazards analysis.

RESULTS

From 1995 to 2012, 111 patients had lobectomy for stage IIIA pN2 NSCLC after chemotherapy ± radiation with an overall 5-year survival of 39%. The use of induction chemoradiation decreased over time; from 1996 to 2007, 46/65 (71%) patients underwent induction chemoradiation, whereas from 2007 to 2012, 36/46 (78%) patients underwent induction chemotherapy. The use of video-assisted thoracoscopic surgery (VATS) increased over the time period of the study, from 0/26 (0%) in 1996-2001, to 4/39 (10%) in 2002-07 to 33/46 (72%) in 2008-12. Compared with patients given induction chemotherapy alone, patients given additional induction radiation were more likely to have complete pathologic response (30 vs 11%, P = 0.01) but had worse 5-year survival in univariable analysis (31 vs 48%, log-rank P = 0.021). Patients who underwent pathologic mediastinal restaging following induction therapy but prior to resection had an improved overall survival compared with patients who did not undergo pathologic mediastinal restaging {5-year survival: 45.2 [95% confidence interval (CI): 33.9-55.9] vs 13.9% (95% CI: 2.5-34.7); log-rank, P = 0.004}. In multivariable analysis, the particular induction therapy strategy and the surgical approach used, as well as the extent of mediastinal disease were not important predictors of survival. However, pathologic mediastinal restaging was associated with improved survival (HR 0.39; 95% CI: 0.21-0.72; P = 0.003).

CONCLUSIONS

For patients with stage IIIA pN2 NSCLC, the VATS approach or the addition of radiation to induction therapy can be selectively employed without compromising survival. The strategy of assessing response to induction therapy with pathologic mediastinal restaging allows one to select appropriate patients for complete resection and is associated with a 5-year overall survival of 39% in this population.

Resectable left lower lobe non-small cell lung cancer with lymph node metastasis is related to unfavorable outcomes

Background

Despite numerous previous studies, the consideration of tumor location as a prognostic factor in resectable non–small cell lung cancer (NSCLC) remains controversial. The present study analyzed the association between tumor location and clinical outcome in patients with resectable NSCLC who had undergone lobectomy with systematic lymphadenectomy and who had presented with varying nodal statuses.

Methods

The data from a cohort of 627 eligible patients treated in Sun Yat-sen University Cancer Center between January 2000 and December 2008 were retrospectively collected, and the nodal statuses of patients with different tumor locations were compared. Cox proportional hazards regression model was used to determine the independent factors related to cancer-specific survival (CSS).

Results

Multivariate analysis demonstrated that left lower lobe (LLL) tumors [hazard ratio (HR): 1.465, 95% confidence interval (CI) 1.090–1.969, P = 0.011], lymph node metastasis (HR: 2.742, 95% CI 2.145–3.507, P < 0.001), and a tumor size of >4 cm (HR: 1.474, 95% CI 1.151–1.888, P = 0.002) were three independent prognosticators in patients with resectable NSCLC. However, LLL tumors were associated only with CSS in node-positive patients (HR: 1.528, 95% CI 1.015–2.301, P = 0.042), and a tumor size of >4 cm was the only independent risk predictor in the node-negative subgroup (HR: 1.889, 95% CI 1.324–2.696, P < 0.001).

Conclusions

Tumor location is related to the long-term CSS of NSCLC patients with lymph node metastasis. LLL tumors may be upstaged in node-positive patients to facilitate an optimal treatment strategy.

Dosimetric evaluation of the feasibility of stereotactic body radiotherapy for primary lung cancer with lobe-specific selective elective nodal irradiation

More than 10% of all patients treated with stereotactic body radiotherapy (SBRT) for primary lung cancer develop regional lymph node recurrence. We evaluated the dosimetric feasibility of SBRT with lobe-specific selective elective nodal irradiation (ENI) on dose-volume histograms. A total of 21 patients were treated with SBRT for Stage I primary lung cancer between January 2010 and June 2012 at our institution. The extents of lobe-specific selective ENI fields were determined with reference to prior surgical reports. The ENI fields included lymph node stations (LNS) 3 + 4 + 11 for the right upper lobe tumors, LNS 7 + 11 for the right middle or lower lobe tumors, LNS 5 + 11 for the left upper lobe tumors, and LNS 7 + 11 for the left lower lobe tumors. A composite plan was generated by combining the ENI plan and the SBRT plan and recalculating for biologically equivalent doses of 2 Gy per fraction, using a linear quadratic model. The V20 of the lung, D(1cm3) of the spinal cord, D(1cm3) and D(10cm3) of the esophagus and D(10cm3) of the tracheobronchial wall were evaluated. Of the 21 patients, nine patients (43%) could not fulfill the dose constraints. In all these patients, the distance between the planning target volume (PTV) of ENI (PTVeni) and the PTV of SBRT (PTVsrt) was ≤2.0 cm. Of the three patients who developed regional metastasis, two patients had isolated lymph node failure, and the lymph node metastasis was included within the ENI field. When the distance between the PTVeni and PTVsrt is >2.0 cm, SBRT with selective ENI may therefore dosimetrically feasible.

[Advances of mediastinal lymph node metastasis and the extent of lymph node dissection in patients with stage T1 non-small cell lung cancer]

肺癌是我国发病率和死亡率最高的恶性肿瘤。非小细胞肺癌（non-small cell lung cancer, NSCLC）约占肺癌80%。临床上，早期NSCLC以手术治疗为主要治疗方式，淋巴结分期及手术中清扫程度直接影响着患者的预后。不同肺叶原发NSCLC的淋巴结转移区域存在一定规律。解剖性肺叶切除加系统性淋巴结清扫一直以来被认为是NSCLC的标准手术方式，但近年来T1期NSCLC手术中纵隔淋巴结清扫的程度存在较大争议，选择性淋巴结清扫已逐渐被大多数学者所重视。

Prognostic Significance of the Number of Metastatic pN2 Lymph Nodes in Stage IIIA-N2 Non-Small-Cell Lung Cancer After Curative Resection

Stage IIIA-N2 non-small cell lung cancer (NSCLC) shows prognostic heterogeneity. We investigated the prognostic relevance of the number of metastatic pN2 nodes in patients with IIIA-N2 NSCLC. The criteria for the number of pN2 used in this study were significantly associated with the survival outcomes after surgery and may improve the accuracy of prognostic prediction in this subgroup of patients.

INTRODUCTION

There have been controversies regarding the prognostic relevance of the number of positive N2 nodes in pathologic stage IIIA-N2 non-small-cell lung cancer (NSCLC). We examine prognosis of patients with pathologic stage IIIA-N2 with classifying the number of positive N2 nodes into subgroups.

METHODS

From January 1997 to December 2004, 250 patients were diagnosed with pathologic stage IIIA-N2 disease. All patients underwent mediastinal lymph node dissection. After excluding 44 patients with preoperative chemotherapy, incomplete resection, and postsurgical mortality, 206 patients were included in the analysis. Patients were classified according to the number of positive N2 lymph nodes (N2a: 1 [n = 83], N2b: 2-4 [n = 82], N2c: ≥ 5 [n = 41]), and its correlation with survival outcomes were investigated.

RESULTS

With a median follow-up of 96.3 months, 5-year disease-free survival (DFS) was 27.2% (95% confidence interval [CI], 21.6-33.7), and 5-year overall survival (OS) was 37.7% (95% CI, 31.5-44.7) in all patients. The number of metastatic N2 lymph nodes was associated with DFS (P < .001) and OS (P = .01). In the N2a, N2b, and N2c groups, 5-year DFS rates were 38%, 24%, and 5%, respectively, and 5-year OS rates were 47%, 35%, and 24%, respectively. In a multivariate analysis, the number of metastatic N2 lymph nodes was an independent prognostic factor for DFS and OS.

CONCLUSION

Stratification of patients according to the number of metastatic N2 lymph nodes may improve the accuracy of prognostic prediction among patients with curatively resected stage IIIA-N2 NSCLC.

Prognosis and segment-specific nodal spread of primary lung cancer in the right lower lobe

Background

Although lobe-specific nodal spread of primary lung cancer has been recently described, segment-specific nodal spread remains unclear. We investigated the frequency of hailer and mediastinal lymph node involvement and survival in patients with tumors located in the superior segment (SS) and basal segment (BS) in the right lower lobe.

Methods

Two hundred and sixty-three patients with primary lung cancer originating in the right lower lobe underwent lobectomy with systematic mediastinal lymph node dissection. Patients were categorized into two groups: SS (n = 114) or BS (n = 149).

Results

Frequencies of metastasis to station 11s and 11i were significantly higher in the SS (P < 0.0001) and BS groups (P = 0.022), respectively. Both the SS and BS groups showed a high frequency of subcarinal mediastinal zone (station 7) metastasis (96.9% and 90.6%, respectively; P = 0.271). The frequencies of superior mediastinal zone (station 2R and 4R) metastasis were 37.5% in the SS and 35.8% in the BS group (P = 0.878). In patients with pN2 disease, three-year disease-free survival was significantly shorter in the SS (22.6%) than the BS group (42.1%; P = 0.020). In the BS group, the independent predictive factors of a poor or good prognosis were metastasis to station 11i or skip metastasis, respectively; however, we did not detect an independent prognostic factor in the SS group. In the right lower lung lobe, there was no segment-specific nodal spread.

Conclusion

When segmentectomy is undertaken, mediastinal lymph node dissection should be performed in proportion to lobectomy.

Lower lobe origin is a poor prognostic factor in locally advanced non-small-cell lung cancer patients treated with induction chemoradiotherapy

The AIM of this study was to identify prognostic factors in patients receiving trimodality therapy for locally advanced non-small-cell lung cancer (NSCLC). Among patients who underwent induction chemoradiotherapy (CRT) followed by surgery between 1999 and 2011 at our institution, 76 NSCLC patients with clinical (c) N2/3 stage III were enrolled in this retrospective study. Induction CRT consisted of docetaxel and cisplatin with concurrent 40-60 Gy radiation therapy. In total, 76 patients were assessed (53 men and 23 women) with 43 adenocarcinomas and 33 non-adenocarcinomas. Of the 76 patients, 44 had cStage IIIA and 32 had cStage IIIB disease. The primary tumors were located in the right upper lobe (N=33), right middle lobe (N=5), right lower lobe (N=11), left upper lobe (N=20s) and left lower lobe (N=7). For all 76 patients, lower lobe tumors were associated with a significantly shorter overall survival (OS) and disease-free survival (DFS) compared to non-lower lobe tumors (OS, P=0.022; and DFS, P=0.0007). When the analysis was limited to pathologically proven N2/3 disease prior to induction CRT (n=36), lower lobe location, compared to other locations, tended to be a poor prognostic factor (OS, P=0.068; and DFS, P=0.0075). Our results indicated that a lower lobe tumor origin is associated with unfavorable prognosis in NSCLC patients treated with induction CRT, strongly suggesting the significance of appropriate patient selection in order to maximize the benefits of trimodality therapy.

Prognostic Factors for Surgically Resected N2 Non-small Cell Lung Cancer

PURPOSE

Non-small cell lung cancers (NSCLCs) with pathologically documented ipsilateral mediastinal lymph node (LN) metastases (pN2) are a broad spectrum of diseases. We retrospectively analyzed prognostic factors for cases of pN2 NSCLC treated by surgical resection.

METHODS

Clinicopathological data were reviewed for consecutive 121 patients who underwent anatomical pulmonary resection with mediastinal LN sampling or dissection for pN2 NSCLC over a 15-year period.

RESULTS

The 5-year survival rate for all patients was 29.9%. Clinical N status, curability, surgical procedure and adjuvant chemotherapy were favorable prognostic factors in univariate analysis, with 5-year survival rates of 35.0% for cN0/1 vs. 17.7% for cN2/3 cases; 33.1% for R0 vs. 14.7% for R1/2 resection; 31.5% for lobectomy vs. 25.0% for bilobectomy and 15.6% for pneumonectomy; and 72.7% with adjuvant chemotherapy vs. 23.8% without adjuvant chemotherapy. Survival did not differ significantly based on gender, age, smoking status, clinical T status, tumor location, histology, skip metastasis, subcarinal LN metastasis, or number of involved N2 levels. In multivariate analysis, adjuvant chemotherapy, R0 resection, and lobectomy emerged as independent favorable prognostic factors.

CONCLUSION

Complete resection using lobectomy and adjuvant chemotherapy are favorable prognostic factors in cases of pN2 NSCLC.

Multimodality treatment with surgery for locally advanced non-small-cell lung cancer with n2 disease: a review article

Stage III non-small-cell lung cancer (NSCLC) is composed of a heterogeneous population of lesions (ie, T4N0-3, T3N1-3, and T1a-2aN2-3), which makes it difficult to establish a definitive treatment strategy. Although several retrospective and prospective studies have been conducted to investigate the significance of multimodality treatments with surgery for patients with resectable stage III NSCLC, the role of surgery still remains controversial. In this article, we review the results of retrospective and prospective studies that have investigated the significance of multimodality treatment with surgery for patients with stage III NSCLC, particularly those with mediastinal lymph node metastasis, and the implications for the treatment of this controversial subset of patients.

Clinical and surgical-pathological staging in early non-small cell lung cancer

Staging is of the utmost importance in the evaluation of a patient with non-small cell lung cancer (NSCLC) because it defines the actual extent of the disease. Accurate staging allows multidisciplinary oncology teams to plan the best surgical or medical treatment and to predict patient prognosis. Based on the recommendation of the International Association for the Study of Lung Cancer (IASLC), a tumor, node, and metastases (TNM) staging system is currently used for NSCLC. Clinical staging (c-TNM) is achieved via non-invasive modalities such as examination of case history, clinical assessment and radiological tests. Pathological staging (p-TNM) is based on histological examination of tissue specimens obtained with the aid of invasive techniques, either non-surgical or during the intervention. This review is a critical evaluation of the roles of current pre-operative staging modalities, both invasive and non-invasive. In particular, it focuses on new techniques and their role in providing accurate confirmation of patient TNM status. It also evaluates the surgical-pathological staging modalities used to obtain the true-pathological staging for NSCLC.

Impact of the 7th TNM staging lung cancer in surgery

Accurate staging of lung cancer is very critical to determine the proper management approach of each patient and to address prognosis issues. In this manuscript, we will discuss the impact of the most recent staging categories (7th TNM staging) on the management of non-small cell lung cancer.

Size of Stage IIIA Primary Lung Cancers and Survival: A Surveillance, Epidemiology and End Results Database Analysis

Size of early-stage lung cancer is important in the prognosis of patients. We examined the large population-based Surveillance, Epidemiology and End Results database to determine if tumor size was an independent risk factor of survival in patients undergoing lobectomy for N2 positive Stage IIIA nonsmall cell lung cancer (NSCLC). This study identified 1971 patients diagnosed with N2 positive Stage IIIA NSCLC, from 1998 to 2007, and who underwent lobectomy. Five tumor groups based on the seventh edition TNM lung cancer staging system (pathologic T1a 2 cm or less; T1b greater than 2 cm and 3 cm or less; T2a greater than 3 cm and 5 cm or less; T2b greater than 5 cm and 7 cm or less; T3 greater than 7 cm) were analyzed. Survival was reduced in patients with T3, T2a, and T2b tumors compared with patients with T1a and T1b ( P < 0.001). Survival estimates correlated with tumor size with poorer survival in T3 followed by T2b, T2a, and then T1b and T1a. Cohorts with T1a (hazard ratio [HR], 0.53; P = 0.01) and T1b (HR, 0.54; P = 0.01) were both found to have decreased hazard of death. Negative predictors of survival, in addition to increasing tumor size, included age and male gender, whereas positive predictors included tumor Grade I and upper lobe location. Increasing size of tumor is an independent negative risk factor for survival in patients undergoing lobectomy for N2 positive Stage IIIA NSCLC.

[Indications and limitations of fresh frozen sections in the pulmonary apparatus]

Recommendations for the diagnosis of lung tumors almost limit the use of fresh frozen sections to the evaluation of resection margins. In pathology pretherapeutic methods for assessment of clinically suspected lung cancer are favored over intraoperative frozen section diagnosis. For the interdisciplinary management of uncertain lung findings diagnostic methods, such as cytopathology and examination of biopsy material are available. The use of rapid on-site evaluation (ROSE) in cytopathology is limited due to the lack of necessary personnel. Diagnosis of unclear pulmonary lesions or distinction of metastases from primary lung tumors by intraoperative frozen sections is therefore limited to exceptional cases that were not resolved by preoperative biopsies. Such rare cases require a common consensus strategy between thoracic surgeons and pathologists in a preoperative tumor board.