Risk of death from intercurrent disease is not excessively increased by modern postoperative radiotherapy for high-risk resected non-small-cell lung carcinoma

Death without progression as an endpoint to describe cardiac radiation effects in locally advanced non-small cell lung cancer

Background and purpose

Prior studies have examined associations of cardiovascular substructure dose with overall survival (OS) or cardiac events after chemoradiotherapy (CRT) for non-small cell lung cancer (NSCLC). Herein, we investigate an alternative endpoint, death without cancer progression (DWP), which is potentially more specific than OS and more sensitive than cardiac events for understanding CRT toxicity.

Materials and methods

We retrospectively reviewed records of 187 patients with locally advanced or oligometastatic NSCLC treated with definitive CRT from 2008 to 2016 at a single institution. Dosimetric parameters to the heart, lung, and ten cardiovascular substructures were extracted. Charlson Comorbidity Index (CCI), excluding NSCLC diagnosis, was used to stratify patients into CCI low (0-2; n = 66), CCI intermediate (3-4; n = 78), and CCI high (≥5; n = 43) groups. Primary endpoint was DWP, modeled with competing risk regression. Secondary endpoints included OS. An external cohort consisted of 140 patients from another institution.

Results

Median follow-up was 7.3 years for survivors. Death occurred in 143 patients (76.5 %), including death after progression in 118 (63.1 %) and DWP in 25 (13.4 %). On multivariable analysis, increasing CCI stratum and mean heart dose were associated with DWP. For mean heart dose ≥ 10 Gy vs < 10 Gy, DWP was higher (5-year rate, 16.9 % vs 6.7 %, p = 0.04) and OS worse (median, 22.9 vs 34.1 months, p < 0.001). Ventricle (left, right, and bilateral) and pericardial but not atrial substructure dose were associated with DWP, whereas all three were inversely associated with OS. Cutpoint analysis identified right ventricle mean dose ≥ 5.5 Gy as a predictor of DWP. In the external cohort, we confirmed an association of ventricle, but not atrial, dose with DWP.

Conclusion

Cardiovascular substructure dose showed distinct associations with DWP. Future cardiotoxicity studies in NSCLC could consider DWP as an endpoint.

Toxicities and Deaths From Intercurrent Disease Following Contemporary Postoperative Radiotherapy in Resected Non-Small-Cell Lung Cancer

INTRODUCTION

The role of postoperative radiotherapy (PORT) in patients with resected locally advanced non-small-cell lung cancer (NSCLC) remains controversial due to the radiation techniques used in randomized trials. We conducted a retrospective cohort study evaluating contemporary PORT techniques to evaluate the safety of PORT and risk of death from intercurrent disease .

MATERIALS AND METHODS

We analyzed consecutive patients with NSCLC treated in a single center that underwent PORT for pN2 disease and/or positive margin, with 3-dimensional conformal radiotherapy (3DRT), intensity modulated radiotherapy , or proton RT (PRT), between 2008 and 2019. Clinical details were collected including intercurrent deaths, defined as death without cancer recurrence. Kaplan-Meier and Cox-Proportional Hazards Models were used.

RESULTS

Of 119 patients, 21 (17.6%) received 3DRT, 47 (39.5%) intensity modulated radiotherapy, and 51 (42.9%) PRT. Median follow-up was 40 months (range 8-136) and median RT dose was 5040cGy. Most patients (65.5%) received sequential adjuvant chemoRT; 18.5% received concurrent chemoRT. The rate of grade 3 toxicities was 9.2%. There were 13 (10.9%) deaths from intercurrent diseases, including 6 from second primary cancers and 2 from cardiopulmonary diseases. There were 2 additional deaths from cardiopulmonary disease in patients with cancer progression at time of death. Mean, V5Gy, V30Gy heart doses and mean lung doses were significantly lower with PRT. Three-year OS and disease-free-survival were 70.1% and 49.9%.

CONCLUSION

PORT using contemporary techniques was well tolerated with acceptable toxicity and low rates of intercurrent deaths. Proton therapy significantly reduced heart and lung doses, but radiotherapy modality was not associated with differences in intercurrent disease.

Analysis of Tumor Mutational Burden, Progression-Free Survival, and Local-Regional Control in Patents with Locally Advanced Non-Small Cell Lung Cancer Treated With Chemoradiation and Durvalumab

IMPORTANCE

The addition of consolidative durvalumab to chemoradiation has improved disease control and survival in locally advanced non-small cell lung cancer (NSCLC). However, there remains a need to identify biomarkers for response to this therapy to allow for risk adaptation and personalization.

OBJECTIVES

To evaluate whether TMB or other variants associated with radiation response are also associated with outcomes following definitive chemoradiation and adjuvant durvalumab among patients with locally advanced unresectable NSCLC.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included consecutive patients with unresectable locally advanced NSCLC treated with chemoradiation and adjuvant durvalumab between November 2013 and March 2020 who had prospective comprehensive genomic profiling. This study was completed at a multisite tertiary cancer center. The median (IQR) follow-up time was 26 (21-36) months. Statistical analysis was conducted from April to October 2022.

EXPOSURES

Patients were grouped into TMB-high (≥10 mutations/megabase [mt/Mb]) and TMB-low (<10 mt/Mb) groups and were additionally evaluated by the presence of somatic alterations associated with radiation resistance (KEAP1/NFE2L2) or radiation sensitivity (DNA damage repair pathway).

MAIN OUTCOMES AND MEASURES

The primary outcomes were 24-month local-regional failure (LRF) and progression-free survival (PFS).

RESULTS

In this cohort study of 81 patients (46 [57%] male patients; median [range] age, 67 [45-85] years), 36 patients (44%) had TMB-high tumors (≥10 mt/Mb). Patients with TMB-high vs TMB-low tumors had markedly lower 24-month LRF (9% [95% CI, 0%-46%] vs 51% [95% CI, 36%-71%]; P = .001) and improved 24-month PFS (66% [95% CI, 54%-84%] vs 27% [95% CI, 13%-40%]; P = .003). The 24-month LRF was 52% (95% CI, 25%-84%) among patients with KEAP1/NFE2L2-altered tumors compared with 27% (95% CI, 17%-42%) among patients with KEAP1/NFE2L2-wildtype tumors (P = .05). On Cox analysis, only TMB status was associated with LRF (hazard ratio [HR], 0.17; 95% CI, 0.03-0.64; P = .02) and PFS (HR, 0.45; 95% CI, 0.21-0.90; P = .03). Histology, disease stage, Eastern Cooperative Oncology Group status, programmed cell death ligand 1 expression, and pathogenic KEAP1/NFE2L2, KRAS, and DNA damage repair pathway alterations were not significantly associated with LRF or PFS.

CONCLUSIONS AND RELEVANCE

In this cohort study, TMB-high status was associated with improved local-regional control and PFS after definitive chemoradiation and adjuvant durvalumab. TMB status may facilitate risk-adaptive radiation strategies in unresectable locally advanced NSCLC.

The prognostic value of postoperative radiotherapy in right tumor for lung related death: based on SEER database and real-world data

Background

Postoperative radiotherapy (PORT) is a therapeutic strategy for patients with non-small cell lung cancer (NSCLC). Nevertheless, some studies suggesting PORT does not improve overall survival (OS) including Lung ART phase III trial. The role of PORT and high-risk groups need to be confirmed.

Methods

Patients from the Surveillance, Epidemiology, and End Results program (SEER) from 2004 to 2015 were eligible. Aged ≥18 years with stage IIIA-N2 NSCLC, accepted PORT or not were considered for the study. Cox regression analyses and multivariate competing risk model were performed. Propensity score matching (PSM) was conducted. Data from a single-center study in China were used for validation.

Results

In all patients with IIIA-N2 NSCLC, death from respiratory illness increased year by year, with right lung-related deaths accounting for the main proportion. In SEER database, PORT was detrimental for OS after PSM (hazard ratio [HR], 1.088; 95% CI, 1.088-1.174; P = 0.031), with a same trend for death from the lungs (HR, 1.13; 95% CI, 1.04-1.22; P = 0.005). Right tumor receiving PORT were prone to death from lung disease(HR, 1.14; 95% CI, 1.02-1.27; P = 0.018). In China single-center cohort, PORT was significantly correlated with deteriorated OS (HR 1.356; 95% CI 1.127-1.632; P <0.01), especially in the right laterality (HR 1.365; 95% CI 1.062-1.755; P = 0.015).

Conclusions

PORT was a risk factor for stage IIIA-N2 NSCLC patients, particularly with characters of right laterality, male sex, age ≥65 years, and advanced tumor stage. These patients are more likely to death from lung disease after PORT.

The efficacy of postoperative radiotherapy for patients with non-small cell lung cancer: An updated systematic review and meta-analysis

The controversy over the efficacy of postoperative radiotherapy (PORT) has existed for a long time. The present study reassessed the overall survival (OS) and disease-free survival (DFS) data to investigate whether PORT can improve survival in resectable non-small cell lung cancer (NSCLC) patients. The following databases were used to perform literature search: PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), and Embase (from January 1, 1986 to July 5, 2021). The results of overall survival (OS) and disease-free survival (DFS) were calculated as hazard ratio (HR). Confidence intervals are chosen with 95% confidence intervals. A total of 12 RCTs and 19 retrospective cohort studies were found to meet the inclusion criteria. A significant DFS improvement was detected in the PORT group (4111 patients from 15 studies), although statistical difference was not detected for OS between the non-PORT and PORT groups (31 studies, 49,342 total patients). PORT prolonged OS in patients undergoing PORT plus postoperative chemotherapy (POCT) and in pN2 patients. Patients with a median radiation dose of 50.4 Gy and a median radiation dose of 54 Gy had a better OS after PORT. However, if the total radiotherapy dose went up to 60 Gy, PORT increased the risk of death in NSCLC patients. Significant difference in OS was not found in the results of studies with regard to treatment methods, pathologic stages, study type, radiation beam quality, and radiation dose. Patients undergoing postoperative chemoradiotherapy and pN2 patients can benefit from PORT. Patients exposed to median radiation doses of 50.4 and 54 Gy demonstrated relatively good efficacy. For patients with non-small-cell lung cancer, PORT has not been proven to extend OS, but its effect on DFS remains strong.

Role of Adjuvant Radiotherapy in Non-Small Cell Lung Cancer-A Review

Simple Summary

The role of postoperative radiotherapy (PORT) in completely resected non-small cell lung cancer (NSCLC) with ipsilateral mediastinal lymph node involvement (pN2) is controversial. The aim of our review was to study the literature relating to PORT for completely resected NSCLC patients with pN2 involvement. The Lung ART and PORT-C trials indicate better locoregional control with PORT, but this has not yet translated into survival benefits. Given the conflicting results, guidelines do not recommend the use of PORT routinely. Future research should focus on identifying subgroups of patients who might benefit from PORT.

Abstract

Background: For patients with completely resected non-small cell lung cancer (NSCLC) with ipsilateral mediastinal lymph node involvement (pN2), the administration of adjuvant chemotherapy is the standard of care. The role of postoperative radiation therapy (PORT) is controversial. Methods: We describe the current literature focusing on the role of PORT in completely resected NSCLC patients with pN2 involvement and reflect on its role in current guidelines. Results: Based on the results of the recent Lung ART and PORT-C trials, the authors conclude that PORT cannot be generally recommended for all resected pN2 NSCLC patients. A substantial decrease in the locoregional relapse rate without translating into a survival benefit suggests that some patients with risk factors might benefit from PORT. This must be balanced against the risk of cardiopulmonary toxicity with potentially associated mortality. Lung ART has already changed the decision making for the use of PORT in daily practice for many European lung cancer experts, with lower rates of recommendations for PORT overall. Conclusions: PORT is still used, albeit decreasingly, for completely resected NSCLC with pN2 involvement. High-level evidence for its routine use is lacking. Further analyses are required to identify patients who would potentially benefit from PORT.

Indications and Parameters Around Postoperative Radiation Therapy for Lung Cancer

Patients with locally advanced resected non-small-cell lung cancer present a high risk of relapse. Although adjuvant platinum-based chemotherapy has become the standard of care, the role of postoperative radiation therapy (PORT) has been controversial for years. In patients with incomplete resection, PORT should be proposed, on the basis of a strong consensus, despite the absence of randomized evidence. In patients with completely resected (R0) non-small-cell lung cancer, a meta-analysis showed poorer outcomes after PORT in the absence of mediastinal involvement (pN0 and pN1). In patients with pN2, the role of PORT was less clear and required further research. The meta-analysis included trials using older radiation techniques and poorer quality of surgery according to today's standards, and selection of patients was not positron emission tomography-based. Newer retrospective and nonrandomized studies and subgroup analyses of randomized trials evaluating adjuvant chemotherapy suggested a survival benefit of PORT in patients with pN2 R0. Two recent randomized trials (Lung ART and PORT-C) evaluating conformal PORT versus no PORT retrieved no disease-free survival advantage for stage IIIA-N2 patients, even if mediastinal relapse was significantly decreased with PORT. PORT had no effect on survival, possibly given the high rate of distant relapse and risk of additional cardiopulmonary toxicity. Ongoing and future analyses are planned in Lung ART to identify patients for whom PORT could be recommended. Incorporation of newer systemic treatments (immune checkpoint inhibitors or targeted therapy in oncogene-addicted patients) is underway in the neoadjuvant and/or adjuvant setting. Better identification of patients at a high risk of disease recurrence, with analysis of circulating tumor DNA, on the basis of the detection of postsurgical minimal (or molecular) residual disease is warranted in future studies.

Radiotherapy for primary lung cancer

Herein are presented the recommendations from the Société française de radiothérapie oncologique regarding indications and modalities of lung cancer radiotherapy. The recommendations for delineation of the target volumes and organs at risk are detailed.

Role of Postoperative Radiotherapy in the Management for Resected NSCLC - Decision Criteria in Clinical Routine Pre- and Post-LungART

BACKGROUND

The role of postoperative radiation therapy (PORT) in stage III N2 NSCLC is controversial. We analyzed decision-making for PORT among European radiation oncology experts in lung cancer.

METHODS

Twenty-two experts were asked before and after presentation of the results of the LungART trial to describe their decision criteria for PORT in the management of pN+ NSCLC patients. Treatment strategies were subsequently converted into decision trees and analyzed.

RESULTS

Following decision criteria were identified: extracapsular nodal extension, incomplete lymph node resection, multistation lymph nodes, high nodal tumor load, poor response to induction chemotherapy, ineligibility to receive adjuvant chemotherapy, performance status, resection margin, lung function and cardiopulmonary comorbidities. The LungART results had impact on decision-making and reduced the number of recommendations for PORT. The only clear indication for PORT was a R1/2 resection. Six experts out of ten who initially recommended PORT for all R0 resected pN2 patients no longer used PORT routinely for these patients, while four still recommended PORT for all patients with pN2. Fourteen experts used PORT only for patients with risk factors, compared to eleven before the presentation of the LungART trial. Four experts stated that PORT was never recommended in R0 resected pN2 patients regardless of risk factors.

CONCLUSION

After presentation of the LungART trial results at ESMO 2020, 82% of our experts still used PORT for stage III pN2 NSCLC patients with risk factors. The recommendation for PORT decreased, especially for patients without risk factors. Cardiopulmonary comorbidities became more relevant in the decision-making for PORT.

Risk of cardiac-related mortality in stage IIIA-N2 non-small cell lung cancer: Analysis of the Surveillance, Epidemiology, and End Results (SEER) database

Background

In this study, we aimed to investigate the association between postoperative radiotherapy (PORT) and cardiac‐related mortality in patients with stage IIIA‐N2 non‐small cell lung cancer (NSCLC) using the Surveillance, Epidemiology, and End Results (SEER) database.

Methods

The United States (US) population based on the SEER database was searched for cardiac‐related mortality among patients with stage IIIA‐N2 NSCLC. Cardiac‐related mortality was compared between the PORT and Non‐PORT groups. Accounting for mortality from other causes, Fine and Gray's test compared cumulative incidences of cardiac‐related mortality between both groups. Univariate and multivariate analysis were performed using the competing risk model.

Results

From 1988 to 2016, 7290 patients met the inclusion criteria: 3386 patients were treated with PORT and 3904 patients with Non‐PORT. The five‐year overall incidence of cardiac‐related mortality was 3.01% in the PORT group and 3.26% in the Non‐PORT group. Older age, male sex, squamous cell lung cancer, earlier year of diagnosis and earlier T stage were independent adverse factors for cardiac‐related mortality. However, PORT use was not associated with an increase in the hazard for cardiac‐related mortality (subdistribution hazard ratio [SHR] = 0.99, 95% confidence interval [CI]: 0.78–1.24, p = 0.91). When evaluating cardiac‐related mortality in each time period, the overall incidence of cardiac‐related mortality was decreased over time. There were no statistically significant differences based on PORT use in all time periods.

Conclusions

With a median follow‐up of 25 months, no significant differences were found in cardiac‐related mortality between the PORT and Non‐PORT groups in stage IIIA‐N2 NSCLC patients.

Evaluation of different treatment strategies between right-sided and left-sided pneumonectomy for stage I-IIIA non-small cell lung cancer patients

Background

This study aimed to assess the different survival outcomes of stage I–IIIA non-small cell lung cancer (NSCLC) patients who received right-sided and left-sided pneumonectomy, and to further develop the most appropriate treatment strategies.

Methods

We accessed data from the Surveillance, Epidemiology, and End Results database from the United States for the present study. An innovative propensity score matching analysis was used to minimize the variance between groups.

Results

For 2,683 patients who received pneumonectomy, cancer-specific survival [hazard ratio (HR) =0.863, 95% confidence interval (CI): 0.771 to 0.965, P=0.010] and overall survival (OS; HR =0.875, 95% CI: 0.793 to 0.967, P=0.008) were significantly superior in left-sided pneumonectomy patients compared with right-sided pneumonectomy patients. Cancer-specific survival (HR =0.847, 95% CI: 0.745 to 0.963, P=0.011) and OS (HR =0.858, 95% CI: 0.768 to 0.959, P=0.007) were also significantly longer with left-sided compared to right-sided pneumonectomy after matching analysis of 2,050 patients. Adjuvant therapy could significantly prolong cancer-specific survival (67 versus 51 months, HR =1.314, 95% CI: 1.093 to 1.579, P=0.004) and OS (46 versus 30 months, HR =1.458, 95% CI: 1.239 to 1.715, P<0.001) among left-sided pneumonectomy patients after the matching procedure, while adjuvant therapy did not increase cancer-specific survival for right-sided pneumonectomy patients (46 versus 42 months, HR =1.112, 95% CI: 0.933 to 1.325, P=0.236). Subgroup analysis showed that adjuvant chemotherapy could significantly improve cancer-specific survival and OS for all pneumonectomy patients. However, radiotherapy was associated with worse survival for patients with right-sided pneumonectomy.

Conclusions

Pneumonectomy side can be deemed as an important factor when physicians determine the most optimal treatment strategies.

Postoperative radiotherapy option based on mediastinal lymph node reclassification for patients with pN2 non-small-cell lung cancer

Background

In this research, we used the mediastinal lymph node reclassification proposed by the International Association for the Study of Lung Cancer (iaslc) to screen for patients with pathologic N2 (pN2) non-small-cell lung cancer (nsclc) who might benefit from postoperative radiotherapy (port).

Methods

The study enrolled 440 patients with pN2 nsclc who received complete surgical resection and allocated them to one of three groups: N2a1 (single-station skip mediastinal lymph node metastasis), N2a2 (single-station non-skip mediastinal lymph node metastasis), and N2b (multi-station mediastinal lymph node metastasis). Rates of local recurrence at first recurrence in patients receiving and not receiving port were compared using the chi-square test. Overall (os) and disease-free survival (dfs) were then compared using Kaplan-Meier survival analysis with log-rank test. In addition, the factors potentially influencing os and dfs were analyzed using univariate and multivariate Cox regression.

Results

The rate of local recurrence for the N2a2 and N2b groups was significantly lower in patients receiving port (p = 0.044 and p = 0.043 respectively). The log-rank test revealed that, for the N2a1 group, differences in os and dfs were not statistically significant between the patients who did and did not receive port (p = 0.304 and p = 0.197 respectively). For the N2a2 group, os and dfs were markedly superior in patients who received port compared with those who did not (p = 0.001 and p = 0.014 respectively). For the N2b group, os was evidently better in patients who received port compared with those who did not (p = 0.025), but no statistically significant difference in dfs was observed (p = 0.134). Multivariate regression analysis revealed that, in the N2a1 group, port was significantly associated with poor os [hazard ratio (hr): 2.618; 95% confidence interval (ci): 1.185 to 5.785; p = 0.017]; in the N2a2 group, port was associated with improved os (hr: 0.481; 95% ci: 0.314 to 0.736; p = 0.001) and dfs (hr: 0.685; 95% ci: 0.479 to 0.980; p = 0.039).

Conclusions

For patients with pN2 nsclc who receive complete resection, port might be beneficial only for patients with single-station non-skip metastasis (N2a2). Patients with single-station skip metastasis (N2a1) and multi-station metastasis (N2b) might not currently benefit from port.

Trends of Postoperative Radiotherapy for Completely Resected Non-small Cell Lung Cancer in China: A Hospital-Based Multicenter 10-Year (2005-2014) Retrospective Clinical Epidemiological Study

Objectives: The role of postoperative radiotherapy (PORT) in the treatment of patients with completely resected non-small cell lung cancer (NSCLC) is not clear. Few study explored the trends of the PORT use. In this study, we examine the status of PORT use of completely resected NSCLC in mainland China.

Methods: From 2005 to 2014, patients with primary lung cancer from eight hospitals across seven geographic regions of mainland China were selected. Then patients with staged I–IIIA NSCLC receiving radical surgery were enrolled in this study. The chi-square test was used to compare differences in the use of PORT among the groups of different age, regions and stages. The Cochran-Armitage trend test was used to identify the trend in the PORT use from 2005 to 2014.

Results: Totally, 2,253 out of 7,184 patients were with staged I–IIIA NSCLC receiving completely resection. Only 122 patients (5.42%) received PORT. During this decade, the use of PORT declined significantly (p = 0.0002). In high socio-economic areas, the percentage of PORT use was 7.43%, which was significantly higher than 1.34% in the low socio-economic areas (p < 0.0001). Age was also associated with PORT use (p = 0.0747). For N0-1 and N2 NSCLC, the proportions of PORT use were 4.01 and 10.22%, respectively (p < 0.0001). And in N0-1 or N2 NSCLC, the proportions both decreased significantly during this decade (p = 0.009 and 0.026, respectively). For stage I, IIA, IIB and IIIA, the proportions who received PORT were 2.59, 4.65, 5.49, and 10.29%, respectively (p < 0.0001). Modern radiation techniques were widely used, but the volumes and doses varied widely. The proportions of using IMRT and EPID/IGRT increased after 2012.

Conclusions: In China, the use of PORT was less than developed countries and had a declined trend. The use of PORT was related to disease stages, patients' age and geographic location. Both in N0-1 and N2 diseases, the use of PORT declined. Proper education of radiation doctors was urgently needed.

The role of postoperative radiotherapy for completely resected pIIIA-N2 non-small cell lung cancer patients with different clinicopathological features: a systemic review and meta-analysis

Background: The role of postoperative radiotherapy (PORT) in completely resected pathological stage IIIA-N2 (pIIIA-N2) non-small cell lung cancer (NSCLC) remains controversial. This meta-analysis aimed to assess the effect of PORT in patients with pIIIA-N2 NSCLC on the basis of clinicopathological features.

Methods: The PubMed, PubMed Central (PMC), Embase, Web of Science, and Cochrane Library were searched for relevant studies. The main outcomes were overall survival (OS) and disease-free survival (DFS), which were compared using the hazard ratio (HR).

Results: One randomized trial and 12 retrospective studies were eligible for the analysis. PORT significantly improved both OS [HR = 0.85; 95% confidence interval (CI): 0.79-0.92] and DFS (HR = 0.57; 95% CI: 0.38-0.85) compared with non-PORT treatment in patients with multiple N2 metastases or multiple N2 station involvement. No significant difference in either OS (HR = 1.03; 95% CI: 0.86-1.24) or DFS (HR = 1.08; 95% CI: 0.70-1.65) was found between PORT and non-PORT groups for patients with single N2 station involvement. No significant heterogeneity was observed. No significant differences in OS were observed between PORT and non-PORT groups for patients of different ages, sex, tumor sizes or pT stages, and histological types.

Conclusions: The findings of this meta-analysis supported a role for PORT in patients with completely resected pIIIA-N2 NSCLC having multiple N2 metastases and favored withholding PORT to patients with single N2 station involvement. Further prospective randomized controlled trials are needed to confirm the findings.

PLNR≤20% may be a benefit from PORT for patients with IIIA-N2 NSCLC: a large population-based study

Purpose

Our study was to evaluate the influence of positive lymph nodes ratio (PLNR) on survival for patients with pathological stage IIIA-N2 non-small cell lung cancer (NSCLC) after receiving postoperative radiotherapy (PORT).

Patients and methods

The chi-squared test was used to compare the patient baseline characteristics. Cox proportional hazard model was used to analyze the influence of different variables on overall survival (OS). X-tile model was applied to determine the cutoff values of PLNR. Kaplan–Meier method and log-rank test were used to compare survival differences. Based on different cutoff values of PLNR, Cox proportional hazard model was also used to analyze the influence factors on OS.

Results

Multivariate Cox regression analysis showed that PLNR (P=0.001) and PORT (HR=1.283; 95% CI 1.154–1.426; P<0.001) were significant independent prognostic factors for OS in patients with resected IIIA-N2 NSCLC. The X-tile model was used to screen three different cutoff values including PLNR≤20%, 20%<PLNR≤40%, PLNR>40%. Based on these different cutoff values, we found that patients with PLNR≤20% receiving PORT have a better OS (P=0.007). Further multivariable analysis showed that PORT is an independent prognostic factor of OS only for patients with PLNR≤20% (HR=1.328; 95% CI 1.139–1.549; P<0.001). Conclusion: PLNR≤20% may be a prognostic factor for patients with IIIA-N2 NSCLC receiving PORT.

Lung dose and the potential risk of death in postoperative radiation therapy for non-small cell lung cancer: A study using the method of stratified grouping

PURPOSE

Postoperative radiation therapy may have a detrimental effect on survival in patients with non-small cell lung cancer. We investigated the association of the lung radiation dose with the risk of death in patients treated with postoperative radiation therapy.

METHODS

We analyzed 178 patients with non-small cell lung cancer who received postoperative radiation therapy. The mean lung dose was calculated from dose-volume data, and we categorized patients into the high and low lung dose groups using 2 different methods; (1) simple grouping using the median lung dose of all patients, and (2) stratified grouping using the median lung dose of each subgroup sharing the same confounders. We compared clinical variables, and survival between the high and low lung dose groups.

RESULTS

In the simple grouping, there were no significant differences in survivals between the high and low lung dose groups. After stratification, the overall survival of low lung dose group was significantly longer than that of high lung dose group (5-year survival, 60.1% vs. 35.3%, p = 0.039). On multivariable analyses, the lung dose remained a significant prognostic factor for overall survival (hazard ratio, HR = 2.08, p = 0.019).

CONCLUSIONS

The lung dose was associated with the risk of death in patients with non-small cell lung cancer having the same confounders. Further studies evaluating the risk of death according to the lung dose will be helpful to administer more precise and individualized postoperative radiation therapy.

Proton therapy for post-operative radiation therapy of non-small cell lung cancer

Post-operative radiation therapy (PORT) is typically recommended for patients with locally advanced non-small cell lung cancer (NSCLC) with N2 mediastinal nodal involvement after surgical resection. The routine use of PORT, however, is controversial as older data demonstrated a detriment in overall survival in patients who received PORT. This detriment was thought to be due to older, more toxic radiation techniques. More recent data with modern radiation techniques demonstrates a local-regional and overall survival benefit with PORT in patients with N2 nodal involvement. Due to the competing risks of local-regional recurrence and cardiopulmonary toxicity in patients who are candidates for PORT, methods to widen the therapeutic window are needed. The physical characteristics of proton beam therapy allow for less radiation dose to the heart and lungs. Therefore, proton beam therapy has great potential in patients undergoing PORT. Initial dosimetric and clinical data have been published and are encouraging, but prospective data is needed to further understand the true benefit of proton therapy in patients undergoing PORT.

Radiotherapy in Italy for Non-Small Cell Lung Cancer: Patterns of Care Survey

Aims and Background

Surveys in clinical practice are useful to find how current clinical approaches follow recommendations from evidence-based medicine, to stimulate discussion in a multidisciplinary team, and to hypothesize collaborative multi-centric trials. To assess management strategies for the use of radiotherapy in the treatment of lung cancer in Italy, in 2009, the Italian Society of Radiation Oncology Lung Cancer Study Group proposed the survey to all Italian radiation oncology institutions. Results were compared with literature data and international reports.

Study Design

Questionnaires on patterns of care of non-small cell lung cancer were sent to radiation oncology centers active at June 2009 and evaluated data recorded in 2008.

Results

A total of 65 of 143 Italian centers responded to the questionnaire. The responding centers reflect the distribution of radiotherapy centers throughout the country. Of the treated patients, 55.2% were stage III, and most cases had a good performance status. FDG-PET was routinely used by 51% of centers for diagnostic and contouring phases. Postoperative radiotherapy was prescribed to pN1 and pN2 patients in 42.2% and 98.5%, respectively. The possible use of neo-adjuvant concomitant chemoradiation was declared by 70% of responders. A sequential chemoradiation approach was actually used in 43.6% of cases, induction chemotherapy followed by concomitant radiochemotherapy in 42.4%, and upfront concomitant radiochemotherapy in only 14%. In 53% of the institutions, patients have a clinical examination by a radiation oncologist only after the beginning of chemotherapy and in 82.4% of cases they have already received 2–4 cycles of chemotherapy. Most of the institutions exclude elective nodal irradiation from routine application. Total dose and fractionation in adjuvant, neoadjuvant, curative and palliative settings confirm literature data. There were significant differences in treatment planning constraints applied for lung, esophageal and cardiac tissues. Of the responding centers, 41% had stereotactic therapy for primary inoperable lung cancer and for metastatic lesions.

Conclusions

In Italy, daily practice differs in some ways from the evidence supported by the results of meta-analyses/clinical trials as regards concurrent chemoradiation approaches. It could be postulated that there is an urgent need for groups that collaborate with the other societies involved in the treatment of non-small cell lung cancer in order to offer the best therapy to our patients.

Choice of postoperative radiation for stage IIIA pathologic N2 non-small cell lung cancer: impact of metastatic lymph node number

Background

Postoperative radiation (PORT) is an option for non-small cell lung cancer (NSCLC) patients with resectable stage IIIA pathological N2 status (pN2). For patients with PORT, this study aims to investigate the impact of the exact number of positive lymph nodes (LNs) on overall survival (OS) and lung cancer-specific survival (LCSS).

Methods

Within the Surveillance, Epidemiology, and End Results database, we identified 3373 patients with stage IIIA pathological N2 status (pN2) NSCLC who underwent a lobectomy or pneumonectomy from 2004 to 2013. OS and LCSS were compared among patients coded as receiving PORT or observation. The proportional hazards model was applied for investigation.

Results

OS and LCSS favored PORT for patients with stage IIIA (pN2) NSCLC. Multivariable analyses showed that PORT and the exact number of positive LNs (n ≤ 3) were independently associated with better OS and LCSS. Both better OS and LCSS emerged for positive LNs (n > 3) after the use of PORT in survival analyses, whereas the benefits of OS and LCSS were not observed anymore for positive LNs (n ≤ 3) group. More importantly, multivariable analyses showed that the use of PORT is an independent risk factor of survival for positive LNs (n > 3) but not for positive LNs (n ≤ 3).

Conclusions

In Stage IIIA (pN2) NSCLC, the use of PORT demonstrated better survival results than no PORT for patients with positive LNs (n > 3), but not for patients with positive LNs (n ≤ 3).

Electronic supplementary material

The online version of this article (10.1186/s13014-017-0946-1) contains supplementary material, which is available to authorized users.

Radiotherapy Dosing for Locally Advanced Non-Small Cell Lung Carcinoma: "MTD" or "ALARA"?

Locally advanced non-small cell lung cancer (LA-NSCLC) is typically treated with thoracic radiotherapy, often in combination with cytotoxic chemotherapy. Despite tremendous advances in the evaluation, treatment techniques, and supportive care measures provided to LA-NSCLC patients, local disease progression and distant metastases frequently develop following definitive therapy. A recent landmark randomized trial demonstrated that radiotherapy dose escalation may reduce survival rates, highlighting our poor understanding of the effects of thoracic radiotherapy for LA-NSCLC. Here, we present rationale for further studies of radiotherapy dose escalation as well as arguments for exploring relatively low radiotherapy doses for LA-NSCLC.

Quantitatively Excessive Normal Tissue Toxicity and Poor Target Coverage in Postoperative Lung Cancer Radiotherapy Meta-analysis

BACKGROUND

A previous meta-analysis (MA) found postoperative radiotherapy (PORT) in lung cancer patients to be detrimental in N0/N1 patients and equivocal in the N2 setting. We hypothesized that treatment plans generated using MA protocols had worse dosimetric outcomes compared to modern plans.

PATIENTS AND METHODS

We retrieved plans for 13 patients who received PORT with modern planning. A plan was recreated for each patient using the 8 protocols included in MA. Dosimetric values were then compared between the modern and simulated MA plans.

RESULTS

A total of 104 MA plans were generated. Median prescribed dose was 50.4 (range, 50-60) Gy in the modern plans and 53.2 (30-60) Gy in the MA protocols. Median planning volume coverage was 96% (93%-100%) in the modern plans, versus 58% (0%-100%) in the MA plans (P < .001). Internal target volume coverage was 100% (99%-100%) versus 65% (0%-100%), respectively (P < .001). Organs at risk received the following doses: spinal cord maximum dose, 36.8 (4.6-50.4) Gy versus 46.8 (2.9-74.0) Gy (P < .001); esophageal mean dose, 22.9 (5.5-35) Gy versus 30.5 (11.1-52.5) Gy (P = .003); heart V30 (percentage of volume of an organ receiving at least a dose of 30 Gy), 16% (0%-45%) versus 35% (0%-79%) (P = .047); mean lung dose, 12.4 (3.4-24.3) Gy versus 14.8 (4.1-27.4) Gy (P = .008); and lung V20, 18% (4%-34%) versus 25% (8%-67%) (P = .023).

CONCLUSION

We quantitatively confirm the inferiority of the techniques used in the PORT MA. Our analysis showed a lower therapeutic ratio in the MA plans, which may explain the poor outcomes in the MA. The findings of the MA are not relevant in the era of modern treatment planning.

Radiation Therapy is Independently Associated with Worse Survival After R0-Resection for Stage I-II Non-small Cell Lung Cancer: An Analysis of the National Cancer Data Base

BACKGROUND

The 1998 post-operative radiotherapy meta-analysis for lung cancer showed a survival detriment associated with radiation for stage I-II resected non-small cell lung cancer (NSCLC), but has been criticized for including antiquated radiation techniques. We analyzed the National Cancer Database (NCDB) to determine the impact of radiation after margin-negative (R0) resection for stage I-II NSCLC on survival.

METHODS

Adult patients from 2004 to 2014 were analyzed from the NCDB with respect to receiving radiation as part of their first course of treatment for resected stage I-II NSCLC; the primary outcome measure was overall survival.

RESULTS

A total of 197,969 patients underwent R0 resection for stage I-II NSCLC, and 4613 received radiation. Median radiation dose was 55 Gy with a 50-60 Gy interquartile range. On adjusted analysis, treatment at a community cancer program, sublobectomy, tumor size (3-7 cm), and pN1/Nx were associated with receiving radiation (odds ratio > 1, p < 0.05). The irradiated group had shorter median survival (45.8 vs. 77.5 months, p < 0.001), and radiation was independently associated with worse overall survival (hazard ratio (HR) 1.339, 95% confidence interval (CI) 1.282-1.399). After propensity score matching, radiation remained associated with worse overall survival (HR 1.313, 95% CI 1.237-1.394, p < 0.001).

CONCLUSIONS

Radiotherapy was independently associated with worse survival after R0 resection of stage I-II NSCLC in the NCDB and was more likely to be delivered in community cancer programs.

Role of Postoperative Radiotherapy in Pathologic Stage IIIA (N2) Non-Small Cell Lung Cancer in a Prospective Nationwide Oncology Outcomes Database

INTRODUCTION

The role of postoperative radiotherapy (PORT) in the treatment of pathologic stage IIIA (N2) NSCLC remains controversial. We investigated practice patterns and outcomes for these patients in a prospectively maintained nationwide oncology outcomes database.

METHODS

Patients with known histologic features of pathologic stage IIIA (N2) NSCLC who underwent an operation with negative margins and received adjuvant multiagent chemotherapy from 2004 to 2013 were identified from the National Cancer Data Base and stratified by the use of PORT. Multivariable logistic regression modeling was used to examine factors associated with receiving PORT, and multivariable proportional hazards regression was used to examine the association of treatment and mortality, adjusting for demographic, socioeconomic and clinicopathologic factors. Landmark analysis and covariate balancing propensity score (CBPS) weighting were also explored to account for immortal time bias and nonrandomization.

RESULTS

A total of 2691 patients were identified, with a median follow-up of 32.32 months. In multivariable analysis, improved overall survival was associated with multiple factors, including younger age, female sex, lower Charlson-Deyo comorbidity index, histologic type (with squamous cell being better than adenocarcinoma), smaller tumor size, lower pathologic T stage, surgical procedure (with pneumonectomy or lobectomy being better than sublobar resection), and receipt of PORT (all p < 0.05). Before landmark analysis, the hazard ratio (HR) showed an overall survival benefit for patients receiving PORT (adjusted HR = 0.83, 95% CI [confidence interval]: 0.72-0.95; p = 0.008). This benefit remained significant after CBPS weighting (HR = 0.81, 95% CI: 0.70-0.94, p = 0.005), almost significant after landmark analysis (adjusted HR = 0.84, 95% CI: 0.69-1.007, p = 0.059), and significant after landmark analysis with CBPS weighting (HR = 0.77, 95% CI: 0.63-0.94, p = 0.009). Median survival past landmark time was 27.43 months in the PORT group and 25.86 months in the non-PORT group. Factors significantly associated with receiving PORT were facility location, facility type, Charlson-Deyo comorbidity index, and grade (all p < 0.05).

CONCLUSIONS

Improved survival is associated with receipt of PORT for patients with pathologic stage IIIA (N2) NSCLC treated with complete resection and multiagent chemotherapy.

Postoperative radiotherapy for lung cancer: Is it worth the controversy?

INTRODUCTION

The role of postoperative radiation therapy (PORT) in patients with completely resected non-small cell lung cancer (NSCLC) with pathologically involved mediastinal lymph nodes (N2) remains unclear. Despite a reduction of local recurrence (LR), its effect on overall survival (OS) remains unproven. Therefore we conducted a review of the current literature.

METHODS

To investigate the benefit and safety of modern PORT, we identified published phase III trials for PORT. We investigated modern PORT in low-risk (ypN0/1 and R0) and high-risk (ypN2 and/or R1/2) patients with stage III-N2 NSCLC treated with induction chemotherapy and resection.

RESULTS

Seventeen phase III trials using PORT were selected. Of all PORT N2 studies, 4 were eligible for evaluation of LR, all in high-risk patients only. In these high-risk patients receiving PORT, the mean LR rate at 5years was 20.9% (95% CI 16-24). Two trials were suitable to assess LR rates after chemotherapy and surgery without PORT. In these low-risk patients, the mean 5-year LR was 33.1% (95% CI 27-39). No significant difference in non-cancer deaths between PORT vs. non-PORT patients was observed in N2 NSCLC.

CONCLUSION

PORT is worth the controversy because data illustrate that PORT may increase the OS. However, prospective randomized trials are needed to verify this.

Sequencing postoperative radiotherapy and adjuvant chemotherapy in non-small cell lung cancer: unanswered questions on the not evidence-based approach

This editorial comments on the study by Lee et al. which reported on the use of postoperative radiotherapy (PORT) as first strategy after resection of stage IIIA-pN2 non-small cell lung cancer (NSCLC). After completion of PORT, 41% of patients received postoperative chemotherapy (POCT). The five-year overall survival (OS) was significantly higher in patients treated with PORT and POCT than in patients treated with PORT alone. Authors concluded that PORT used as first postoperative strategy does not compromise a benefit of POCT and its implementation should be further studied. We discuss the pros and cons of using PORT before POCT for stage IIIA-pN2 NSCLC. Some radiobiological data support earlier use of PORT, however, caution should be paid to not to unnecessarily delay or omit POCT because of its demonstrated survival benefit. Concurrent postoperative radio-chemotherapy could be an attractive approach, but we still have very limited clinical data on its use in this indication.

Outcome after PORT in ypN2 or R1/R2 versus no PORT in ypN0 Stage III-N2 NSCLC after Induction Chemotherapy and Resection

INTRODUCTION

We investigated patients with contemporarily staged and treated stage III-N2 NSCLC treated with induction chemotherapy and surgery with or without postoperative radiotherapy (PORT). We focused on survival and toxicity and investigated what additional PORT may offer in patients with ypN2 status or incomplete resection.

METHODS

We identified 161 patients with pathologically proven, resectable stage III-N2 NSCLC from our prospective database who were treated between 1998 and 2012. Of these patients, 150 without progressive disease after chemotherapy underwent resection. Patients with ypN2 status or R1/2 resection received three-dimensional PORT (n = 70) to a dose of 50 to 66 Gy in 2-Gy fractions.

RESULTS

The mean follow-up time was 49 months. The 5-year overall survival (OS) rate was 35.1% in intention-to-treat analysis; relapse-free survival was 31.8%, the cumulative local recurrence (LR) rate was 50.9%, and the distant metastasis rate was 63.4%. The 5-year OS, relapse-free survival, and cumulative LR and distant metastasis rates were 32.0%, 32.9%, 47.0%, and 63.9% in the PORT group versus 38.1%, 30.7%, 54.1%, and 63.2% in the non-PORT group. These results were not significantly different, even though patients in the PORT group had worse prognostic features. Cardiac toxicity was higher in the non-PORT group (p = 0.02), but pulmonary toxicity was similar (p = 0.15). There was no difference between the two groups regarding dyspnea (p = 0.32), cough (p = 0.37), forced expiratory volume in 1 second (p = 0.30), and diffusing capacity of the lung for carbon monoxide (p = 0.61).

CONCLUSIONS

A similar outcome (OS, LR, and toxicity) was seen in both patient groups (PORT versus non-PORT group). Despite the limitations of this retrospective study, PORT can be both effective and safe for patients with stage III-N2 NSCLC with an R1/R2 resection or yN2 after induction chemotherapy and surgery.

Therapeutic options following pneumonectomy in non-small cell lung cancer

INTRODUCTION

Pneumonectomy can be considered the most appropriate treatment for lung cancer that cannot be removed by lesser resection on.

AREAS COVERED

Therapeutic options following pneumonectomy may be required at least in 3 different scenarios: 1) an early approach due to acute surgical complications 2) a late approach due to chronic surgical complications 3) an integrated radio-chemotherapeutic adjuvant approach for advanced stages. In this review we focused on these three settings with particular emphasis to surgical approach as well as to alternative options. Expert commentary: Pneumonectomy itself does not preclude postoperative additional treatments, if needed, to maximize oncological results and to manage potential short or long term complications. However, as pneumonectomy puts a significant physiological stress on the respiratory and circulatory systems, the benefits and risks of pneumonectomy should be compared with those of alternative, non-resectional treatment modalities.

Delineation of clinical target volume for postoperative radiotherapy in stage IIIA-pN2 non-small-cell lung cancer

With the high locoregional relapse rate and the improvement of radiation technology, postoperative radiotherapy (PORT) has been widely used in the treatment of completely resected stage IIIA-pN2 non-small-cell lung cancer (NSCLC). However, there is still no definitive consensus on clinical target volume for the pN2 subgroup. This review will discuss how to delineate the clinical target volume (CTV) for pN2 subgroups of IIIA-N2 NSCLC based on the published literature and to investigate the optimal PORT CTV in this cohort of patients. Besides overall survival (OS), locoregional recurrence (LR), and radiotherapy-related toxicity of this subset of the population in the modern PORT era, selection of proper patients will also be considered in this review. In summary, it is appropriate to include involved lymph node stations and uninvolved stations at high risk in PORT CTV for patients with pN2 disease when PORT is administered. PORT can reduce LR and has the potential to improve OS. In the current era of modern radiation technology, PORT can be administered safely with well-tolerated toxicity. Clinicopathological characteristics may be helpful in selecting proper candidates for PORT.

Radiation Therapy-First Strategy After Surgery With or Without Adjuvant Chemotherapy in Stage IIIA-N2 Non-Small Cell Lung Cancer

PURPOSE

Postoperative radiation therapy (PORT) and postoperative chemotherapy (POCT) can be administered as adjuvant therapies in patients with non-small cell lung cancer (NSCLC). The aim of this study was to present the clinical outcomes in patients treated with PORT-first with or without subsequent POCT in stage IIIA-N2 NSCLC.

METHODS AND MATERIALS

From January 2002 to November 2014, the conditions of 105 patients with stage IIIA-N2 NSCLC who received PORT-first with or without subsequent POCT were analyzed. PORT was initiated within 4 to 6 weeks after surgical resection. Platinum-based POCT was administered 3 to 4 weeks after the completion of PORT. We analyzed the outcomes and the clinical factors affecting survival.

RESULTS

Of 105 patients, 43 (41.0%) received POCT with a median of 4 cycles (range, 2-6 cycles). The follow-up times ranged from 3 to 123 months (median, 30 months), and the 5-year overall survival (OS) was 40.2%. The 5-year OS of patients treated with PORT and POCT was significantly higher than that of patients with PORT (61.3% vs 29.2%, P<.001). The significant prognostic factors affecting OS were the use of POCT (hazard ratio [HR] = 0.453, P=.036) and type of surgery (pneumonectomy/lobectomy; HR = 2.845, P<.001).

CONCLUSIONS

PORT-first strategy after surgery appeared not to compromise the clinical outcomes in the treatment of stage IIIA-N2 NSCLC. The benefit of POCT on OS was preserved even in the PORT-first setting. Further studies are warranted to compare the sequencing of PORT and POCT, guaranteeing the proper use of POCT.

Association Between Radiation Dose and Outcomes With Postoperative Radiotherapy for N0-N1 Non-Small Cell Lung Cancer

PURPOSE

To review trends in the use of postoperative radiotherapy (PORT) in the modern era for N0-N1 margin-negative non-small cell lung cancer (NSCLC) following surgical resection and evaluate the association between PORT dose and overall survival.

MATERIALS AND METHODS

We performed a retrospective study of nonmetastatic stage II and III N0-N1 margin-negative NSCLC surgically treated patients within the National Cancer Data Base from 2003 to 2011. Cox proportional hazards regression was performed for multivariable analyses of overall survival and PORT dose. Radiation modalities included nonconformal beam radiation, 3-dimensional conformal radiation (3D-CRT), and intensity-modulated radiation therapy.

RESULTS

We identified 2167 (6.7%) and 30,269 (93.3%) patients with surgically resected stage II or III N0-N1 margin-negative NSCLC who were treated with and without PORT, respectively. The proportion of patients treated with PORT (dose range, 45 to 74 Gy) decreased from 8.9% in 2003 to 2006 to 4.1% in 2010 to 2011. Among patients receiving PORT, the use of high-dose (60 to 74 Gy) PORT rose throughout the study period, starting at 34.8% in 2003 to 2006 and rising to 49.3% in 2010 to 2011.Overall, patients who received PORT had worse survival (hazards ratio=1.30; 95% confidence interval, 1.20-1.40) compared with those not receiving PORT. This association was unchanged when limited to patients receiving modern treatment with 3-CRT or intensity-modulated radiation therapy (hazards ratio=1.35; 95% confidence interval, 1.10-1.65).

CONCLUSIONS

The use of PORT for N0-N1 margin-negative NSCLC decreased from 2003 to 2011. We found no evidence of benefit from PORT for resected N0-N1 margin-negative NSCLC, regardless of dose or technique. PORT should be approached with caution in this group of patients, regardless of radiotherapy technique.

Evidence-based recommendations of postoperative radiotherapy in lung cancer from Oncologic Group for the Study of Lung Cancer (Spanish Radiation Oncology Society)

Locally advanced non-small cell lung cancer (NSCLC) is a diversified illness in which postoperative radiation therapy (PORT) for complete resection with positive hiliar (pN1) and/or mediastinal (pN2) lymph nodes is controversial. Although several studies have shown that PORT has beneficial effects, randomized trials are needed to demonstrate its impact on overall survival. In this review, the Spanish Radiation Oncology Group for Lung Cancer describes the most relevant literature on PORT in NSCLC patients stage pN1-2. In addition, we have outlined the current recommendations of different national and international clinical guidelines and have also specified practical issues regarding treatment volume definition, doses and fractionation.

Role of adjuvant radiotherapy in completely resected non-small-cell lung cancer

Most long-term survivors of non-small-cell lung cancer (NSCLC) are patients who have had a completely resected tumour. However, this is only achievable in about 30% of the patients. Even in this highly selected group of patients, there is still a high risk of both local and distant failure. Adjuvant treatments such as chemotherapy (CT) and radiotherapy (RT) have therefore been evaluated in order to improve their outcome. In patients with stage II and III, administration of adjuvant platinum-based chemotherapy is now considered the standard of care, based on level 1 evidence. The role of postoperative radiation therapy (PORT) remains controversial. In the PORT meta-analysis published in 1998, the conclusions were that if PORT was detrimental to patients with stage I and II completely resected NSCLC, the role of PORT in the treatment of tumours with N2 involvement was unclear and further research was warranted. Thus at present, after complete resection, adjuvant radiotherapy should not be administered in patients with early lung cancer. Recent retrospective and non-randomised studies, as well as subgroup analyses of recent randomised trials evaluating adjuvant chemotherapy, provide evidence of the possible benefit of PORT in patients with mediastinal nodal involvement. The role of PORT needs to be evaluated also for patients with proven N2 disease who undergo neoadjuvant chemotherapy followed by surgery. The risk of local recurrence for N2 patients varies between 20% and 60%. Based on currently available data, PORT should be discussed for fit patients with completely resected NSCLC with N2 nodal involvement, preferably after completion of adjuvant chemotherapy or after surgery if patients have had preoperative chemotherapy. There is a need for new randomised evidence to reassess PORT using modern three-dimensional conformal radiation technique, with attention to normal organ sparing, particularly lung and heart, to reduce the possible over-added toxicity. Quality assurance of radiotherapy as well as quality of surgery – and most particularly nodal exploration modality – should both be monitored. A new large multi-institutional randomised trial Lung ART evaluating PORT in this patient population is needed and is now under way.

Proton Beam Therapy for Non-Small Cell Lung Cancer: Current Clinical Evidence and Future Directions

Lung cancer is the leading cancer cause of death in the United States. Radiotherapy is an essential component of the definitive treatment of early-stage and locally-advanced lung cancer, and the palliative treatment of metastatic lung cancer. Proton beam therapy (PBT), through its characteristic Bragg peak, has the potential to decrease the toxicity of radiotherapy, and, subsequently improve the therapeutic ratio. Herein, we provide a primer on the physics of proton beam therapy for lung cancer, present the existing data in early-stage and locally-advanced non-small cell lung cancer (NSCLC), as well as in special situations such as re-irradiation and post-operative radiation therapy. We then present the technical challenges, such as anatomic changes and motion management, and future directions for PBT in lung cancer, including pencil beam scanning.

Postoperative Radiation Therapy Is Associated With Improved Overall Survival in Incompletely Resected Stage II and III Non-Small-Cell Lung Cancer

PURPOSE

To review trends in the use of postoperative radiotherapy (PORT) for stage II and III incompletely resected non-small-cell lung cancer (NSCLC) and evaluate the association between PORT and survival in such patients.

PATIENTS AND METHODS

We identified patients with pathologic stage N0-2, overall American Joint Committee on Cancer stage II or III NSCLC within the National Cancer Data Base who had undergone a lobectomy or pneumonectomy with positive surgical margins. Only patients coded as receiving external-beam PORT at 50 to 74 Gy or observation were included. To account for perioperative mortality, we excluded patients who survived less than 4 months after diagnosis. Multivariable logistic regression was used to determine factors associated with PORT receipt. Cox proportional hazards regression was performed for multivariable analyses of overall survival.

RESULTS

Among 3,395 included patients, 1,207 (35.6%) received PORT. Predictors for the use of PORT among this patient population included age less than 60 years, treatment in a nonacademic facility, earlier year of diagnosis, decreased travel distance, lower nodal stage, and chemotherapy receipt. On multivariable analysis adjusting for demographic and clinicopathologic covariates, PORT (hazard ratio, 0.80; 95% CI, 0.70 to 092) was associated with improved survival. Subset analysis by nodal stage showed that PORT improved survival across all nodal stages.

CONCLUSION

PORT is associated with improved overall survival in patients with incompletely resected stage II or III N0-2 NSCLC. The use of PORT for this population in more recent years has been declining. In the absence of randomized trials evaluating PORT utilization for this patient population, our findings strongly support the delivery of PORT in patients with incompletely resected NSCLC.

Post-operative radiation therapy

In completely resected non-small-cell lung cancer (NSCLC) patients with pathologically involved mediastinal lymph nodes (N2), administration of adjuvant platinum-based chemotherapy is now considered the standard of care, based on level 1 evidence. The role of post-operative radiotherapy (PORT) in this group of patients remains controversial. In the PORT meta-analysis published in 1998, the conclusions were that if adjuvant radiotherapy was detrimental to patients with early-stage completely resected NSCLC, the role of PORT in the treatment of tumours with N2 involvement was unclear and further research was warranted. Recent retrospective and non-randomized studies as well as subgroup analyses of recent randomized trials evaluating adjuvant chemotherapy, provide evidence of the possible benefit of PORT in patients with mediastinal nodal involvement. The question of PORT indication is also valid for those patients with proven N2 disease who undergo neo-adjuvant chemotherapy followed by surgery. The risk of local recurrence for N2 patients varies between 20% and 60%. Based on currently available data, PORT should be discussed for fit patients with completely resected NSCLC with N2 nodal involvement, within a multidisciplinary setting, preferably after completion of adjuvant chemotherapy or after surgery if patients have had neo-adjuvant chemotherapy. There is need for new randomized evidence to reassess PORT using modern three-dimensional conformal radiation technique, with attention to normal organ sparing, particularly lung and heart, to reduce the possible additional toxicity. Randomized evidence is needed. A new large international multi-institutional randomized trial Lung ART evaluating PORT in this patient population is now underway, as well as a Chinese study comparing postoperative sequential chemotherapy followed by radiotherapy versus adjuvant chemotherapy alone.

Postoperative radiotherapy for pathologic N2 non-small-cell lung cancer treated with adjuvant chemotherapy: a review of the National Cancer Data Base

PURPOSE

To investigate the impact of modern postoperative radiotherapy (PORT) on overall survival (OS) for patients with N2 non-small-cell lung cancer (NSCLC) treated nationally with surgery and adjuvant chemotherapy.

PATIENTS AND METHODS

Patients with pathologic N2 NSCLC who underwent complete resection and adjuvant chemotherapy from 2006 to 2010 were identified from the National Cancer Data Base and stratified by use of PORT (≥ 45 Gy). A total of 4,483 patients were identified (PORT, n = 1,850; no PORT, n = 2,633). The impact of patient and treatment variables on OS was explored using Cox regression.

RESULTS

Median follow-up time was 22 months. On univariable analysis, improved OS correlated with younger age, treatment at an academic facility, female sex, urban population, higher income, lower Charlson comorbidity score, smaller tumor size, multiagent chemotherapy, resection with at least a lobectomy, and PORT. On multivariable analysis, improved OS remained independently predicted by younger age, female sex, urban population, lower Charlson score, smaller tumor size, multiagent chemotherapy, resection with at least a lobectomy, and PORT (hazard ratio, 0.886; 95% CI, 0.798 to 0.988). Use of PORT was associated with an increase in median and 5-year OS compared with no PORT (median OS, 45.2 v 40.7 months, respectively; 5-year OS, 39.3% [95% CI, 35.4% to 43.5%] v 34.8% [95% CI, 31.6% to 38.3%], respectively; P = .014).

CONCLUSION

For patients with N2 NSCLC after complete resection and adjuvant chemotherapy, modern PORT seems to confer an additional OS advantage beyond that achieved with adjuvant chemotherapy alone.

Prognostic implication of pulmonary function at the beginning of postoperative radiotherapy in non-small cell lung cancer

PURPOSE

The purpose of this study was to investigate the prognostic effect of pulmonary function at the beginning of postoperative radiotherapy (PORT) in non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

From January 2002 to December 2012, 115 patients with NSCLC who underwent PORT and took the forced expiratory volume in 1 second (FEV1) at the beginning of PORT were analysed. PORT began within 4-6weeks following surgery, and the 3-dimensional conformal technique was used with conventional fractionation. The high and low FEV1 groups were divided by the median absolute value of FEV1 at the beginning of PORT, and we compared the clinical factors and survival between two groups.

RESULTS

The median absolute value of FEV1 at the beginning of PORT was 1.68L (range, 0.83-3.89), and patients were divided into low and high FEV1 groups (<1.68L versus ⩾1.68L). Patients in the low FEV1 group showed a lower preoperative FEV1 (mean, 1.94L versus 2.73L, p<0.001) and received more pneumonectomy (36.8% versus 8.6%, p<0.001) compared to the high FEV1 group. The overall median follow-up time was 31months (range, 3-110), and 5-year locoregional recurrence-free survival (LRRFS), distant metastasis-free survival (DMFS) and overall survival (OS) were 52.4%, 48.9%, and 45.9%, respectively. Five-year OS of the low FEV1 group was significantly lower than that of the high FEV1 group (35.4% versus 56.9%, p=0.002), and no significant differences were found in LRRFS and DMFS. In a multivariate analysis, the difference of OS between the low and high FEV1 groups remained significant (Hazard Ratio=2.04, CI, 1.18-3.55, p=0.011).

CONCLUSIONS

The FEV1 at the beginning of PORT was an independent significant prognostic factor in patients with NSCLC who received PORT. Considering this analysis was limited to only patients receiving PORT, further studies are warranted to compare the survival effect of postoperative pulmonary function between groups with/without PORT.

Predictive factors for survival in stage IIIA N2 NSCLC patients treated with neoadjuvant CCRT followed by surgery

PURPOSE

To assess the impact of imaging, surgical, histopathologic and patient-related factors on the risks of recurrence and overall survival (OS) in stage IIIA-N2 non-small cell lung cancer (NSCLC) patients undergoing definitive resection after neoadjuvant concurrent chemoradiotherapy (CCRT).

METHODS

We retrospectively examined 104 consecutive patients with stage IIIA-N2 NSCLC who received neoadjuvant CCRT followed by surgery between 2008 and 2011. While reviewing the clinical and surgical data, we also assessed histopathologic and imaging (CT and PET/CT) factors. Disease-free survival (DFS) and OS were estimated with predictors for recurrence and survival.

RESULTS

The 3-year OS for patients with and without recurrence was 37.1 and 63.3 %, respectively (p < 0.001). Size decrease of target lesion(s) ≥36 % on post-neoadjuvant CCRT CT (p = 0.048) and viable tumor size on surgical specimen <9.4 mm (p = 0.035) were related to longer OS. Regarding shorter DFS, tumor size on post-neoadjuvant CCRT CT (p = 0.046), SUV(max) of the primary tumor (p = 0.011), male gender (p = 0.023), total tumor size on surgical specimen (p = 0.041) and viable tumor size on surgical specimen (p = 0.043) were the significant predictors.

CONCLUSIONS

OS is prolonged with greater extent of size decrease of target lesion(s) on post-neoadjuvant CCRT CT and smaller viable tumor size on surgical specimen. Larger tumor size on post-neoadjuvant CCRT CT, higher SUV(max), male gender, larger total tumor size and larger viable tumor size on surgical specimen may herald the higher probability of recurrence and the necessity of more attention.

Adjuvant chemotherapy and radiotherapy in the treatment of non-small cell lung cancer (NSCLC)

Lung cancer is one of the most common human malignancies and remains the leading cause of cancer related deaths worldwide. Many recent technological advances led to improved diagnostics and staging of lung cancer. With development of new treatment options such as targeted therapies there might be improvement in progression free survival of patients with advanced stage non-small cell lung cancer (NSCLC). Improvement in overall survival is still reserved for selected patients and selected treatments. One of the mostly investigated therapeutic options is adjuvant treatment. There are many open issues in selection of patients and administration of appropriate adjuvant treatment.

Modern post-operative radiotherapy for stage III non-small cell lung cancer may improve local control and survival: a meta-analysis

BACKGROUND

We hypothesized that modern postoperative radiotherapy (PORT) could decrease local recurrence (LR) and improve overall survival (OS) in patients with stage IIIA-N2 non-small-cell lung cancer (NSCLC).

METHODS

To investigate the effect of modern PORT on LR and OS, we identified published phase III trials for PORT and stratified them according to use or non-use of linear accelerators. Non-individual patient data were used to model the potential benefit of modern PORT in stage IIIA-N2 NSCLC treated with induction chemotherapy and resection.

RESULTS

Of the PORT phase III studies, eleven trials (2387 patients) were included for OS analysis and eight (1677 patients) for LR. PORT decreased LR, whether given with cobalt, cobalt and linear accelerators, or with linear accelerators only. An increase in OS was only seen when PORT was given with linear accelerators, along with the most significant effect on LR (relative risk for LR and OS 0.31 (p=0.01) and 0.76 (p=0.02) for PORT vs. controls, respectively). Four trials (357 patients) were suitable to assess LR rates in stage III NSCLC treated with surgery, in most cases after induction chemotherapy. LR as first relapse was 30% (105/357) after 5 years. In the modeling part, PORT with linear accelerators was estimated to reduce LR rates to 10% as first relapse and to increase the absolute 5-year OS by 13%.

CONCLUSIONS

This modeling study generates the hypothesis that modern PORT may increase both LR and OS in stage IIIA-N2 NSCLC even in patients being treated with induction chemotherapy and surgery.

An in-silico comparison of proton beam and IMRT for postoperative radiotherapy in completely resected stage IIIA non-small cell lung cancer

INTRODUCTION

Post-operative radiotherapy (PORT) for stage IIIA completely-resected non-small cell lung cancer (CR-NSCLC) has been shown to improve local control; however, it is unclear that this translates into a survival benefit. One explanation is that the detrimental effect of PORT on critical organs at risk (OARs) negates its benefit. This study reports an in-silico comparative analysis of passive scattering proton therapy (PSPT)- and intensity modulated proton therapy (IMPT) with intensity modulated photon beam radiotherapy (IMRT) PORT.

METHODS

The computed tomography treatment planning scans of ten patients with pathologic stage IIIA CR-NSCLC treated with IMRT were used. IMRT, PSPT, and IMPT plans were generated and analyzed for dosimetric endpoints. The proton plans were constructed with two or three beams. All plans were optimized to deliver 50.4 Gy(RBE) in 1.8 Gy(RBE) fractions to the target volume.

RESULTS

IMPT leads to statistically significant reductions in maximum spinal cord, mean lung dose, lung volumes treated to 5, 10, 20, and 30 Gy (V5, V10, V20, V30), mean heart dose, and heart volume treated to 40 Gy (V40), when compared with IMRT or PSPT. PSPT reduced lung V5 but increased lung V20, V30, and heart and esophagus V40.

CONCLUSIONS

IMPT demonstrates a large decrease in dose to all OARs. PSPT, while reducing the low-dose lung bath, increases the volume of lung receiving high dose. Reductions are seen in dosimetric parameters predictive of radiation pneumonitis and cardiac morbidity and mortality. This reduction may correlate with a decrease in dose-limiting toxicity and improve the therapeutic ratio.

Chemoradiation for definitive, preoperative, or postoperative therapy of locally advanced non-small cell lung cancer

Over the last few decades, the integration of chemotherapy and radiation has played a crucial role in the management of locally advanced non-small cell lung cancer (NSCLC). Locally advanced NSCLC is a very heterogeneous disease. Because of this heterogeneity, advanced NSCLC can be managed in various ways depending on the bulk of disease, the comorbidities of the patient, and the expertise and resources of the treating physicians and facilities. This review describes the evolution of current treatment strategies and predicted future changes for the management of locally advanced NSCLC.