Prognostic index for estimating the survival benefit of postoperative radiotherapy in pathologic N2 non-small cell lung cancer: A real-world validation study

Uncertain Resection in Lung Cancer: A Comprehensive Review of the International Association for the Study of Lung Cancer Classification

Objective: We explored the impact of uncertain resection in lung cancer on overall survival and disease-free survival. Methods: We performed an exhaustive literature review of all studies comparing prognosis after resection according to the IASLC classification, from the PubMed, Cochrane, MEDLINE, and Google Scholar databases. Results: Overall, 68 original studies were included, of which 67 were retrospective and 1 was prospective, with 81 785 patients included over 46 years. R(un) reclassification was mostly caused by a lack of hilar or mediastinal node dissection, or because of metastasis in the highest node. R(un) is a strong factor for higher recurrence and mortality, while its effects seem limited in early stages. Carcinoma in situ at bronchial margin resection (CIS BRM) does not show an effect on survival, while positive pleural cytology (Cy+) and positive highest mediastinal lymph node (HMLN+) appear to be highly predictive of recurrence and death. Discussion: The R(un) classification of the IASLC appears highly relevant, especially in locally advanced stages IIb-IIIA, and helps to discriminate patients with poor prognosis despite being classified as R0 in the UICC classification. Conclusions: The use of this more precise classification would allow for better stratification of recurrence risk and more effective use of adjuvant therapies. Cy+ patients should receive adjuvant chemotherapy, while CIS BRM patients could likely benefit from endoscopic surveillance to detect local recurrences. HMLN+ patients should be considered at high risk of recurrence, and adjuvant radio-chemotherapy should be considered.

Is postoperative radiotherapy effective in patients with completely resected pathologic stage IIIA(N2) non-small cell lung cancer? High-risk populations should consider it

Background and purpose

We aimed to assess the benefits of postoperative radiotherapy (PORT) in completely resected patients with pathologic stage IIIA(N2) non-small cell lung cancer (NSCLC) with a high risk of locoregional recurrence (LRR).

Materials and methods

A prospective, randomized trial was conducted starting in July 2016 to explore the optimal timing of PORT in high-LRR-risk patients with completely resected IIIA(N2) NSCLC (NCT02974426). Patients were identified as high-LRR-risk patients via the prognostic index (PI) model and were randomly assigned to PORT-first or PORT-last treatment. To evaluate PORT for high-LRR-risk patients, all patients in this trial constituted the PORT cohort, whereas high-LRR-risk patients without PORT were selected from a retrospective cohort as the non-PORT cohort. Propensity score-matched (PSM) analyses were conducted to compare overall survival (OS), disease-free survival (DFS), locoregional recurrence-free survival (LRFS) and distant metastasis-free survival (DMFS).

Results

Between 2016 and 2022, 132 patients were included in the trial, with a median follow-up of 49.3 months. The 3-year OS rate was 83.2 %, and the 3-year DFS rate was 35.0 %. Among these patients, 122 patients (92 %) received planned PORT. For 132 intention-to-treat patients, PSM analysis with the non-PORT cohort (n = 307) resulted in 130 matched pairs. The results revealed that PORT improved LRFS (3-year LRFS, 77.6 % vs. 57.3 %; p = 0.00014), DFS (3-year DFS, 35.2 % vs. 28.6 %; p = 0.038), and OS (3-year OS, 83.0 % vs. 60.7 %; p = 0.00017), with no difference in DMFS (p = 0.17).

Conclusion

PORT could increase local control, DFS, and OS in high-LRR-risk patients with completely resected IIIA(N2) NSCLC. Future research should utilize multidimensional data to pinpoint more precise subgroups benefiting from PORT, with prospective trials validating these findings.

The high-risk features and effect of postoperative radiotherapy on survival for patients with surgically treated stage IIIA-N2 non-small cell lung cancer

OBJECTIVES

Although postoperative radiotherapy (PORT) could reduce the incidence of local recurrence in patients with IIIA-N2 non-small cell lung cancer (NSCLC), the role of PORT on survival in patients with surgically treated stage IIIA-N2 NSCLC remains controversial. Therefore, this study was designed to evaluate the effect of PORT on survival for patients with surgically treated stage IIIA-N2 NSCLC.

MATERIALS AND METHODS

This study population was chosen from the Surveillance, Epidemiology, and End Results database. The Cox proportional hazards regression analysis was used to determine significant contributors to overall survival (OS) and cancer special survival (CSS) outcomes. To balance baseline characteristics between the non-PORT group and PORT group, propensity score matching (PSM) with 1:1 propensity nearest-neighbor match by 0.001 matching tolerance was conducted by R software. Furthermore, a Kaplan-Meier curve was used to visualize the OS and CSS between the PORT group and non-PORT group survival probability.

RESULTS

Of all evaluated cases, 4511 with IIIA-N2 NSCLC were eligible for inclusion, of which 1920 were enrolled into the PORT group. On univariate analysis and multivariate analysis, sex, age, year of diagnosis, race, histologic type, T stage, PORT, use of chemotherapy, and positive regional nodes were significantly associated with OS and CSS in IIIA-N2 NSCLC (P < 0.05). However, PORT was not significantly associated with OS (univariate HR = 0.92, 95%CI 0.85-0.99, P = 0.02; multivariate HR = 1.01, 95%CI 0.93-1.08, P = 0.91) and CSS (univariate HR = 0.92, 95%CI 0.85-1.01, P = 0.06; multivariate HR = 1.103 95%CI 0.94-1.12, P = 0.56) in IIIA-N2 NSCLC. Meanwhile, after PSM, neither OS nor CSS did differ significantly between the non-PORT group and PORT group (OS HR = 1.08, 95%CI 0.98-1.19, P = 0.12; CSS HR = 1.10, 95%CI 0.99-1.23, P = 0.07).

CONCLUSION

PORT did not contribute to a survival benefit in patients with surgically treated stage IIIA-N2 NSCLC.

Update on Adjuvant Treatment in Resectable Non-Small Cell Lung Cancer and Potential Biomarkers Predicting Postoperative Relapse

A significant proportion of patients with non-small cell lung cancer (NSCLC) is diagnosed in the early and resectable stage. Despite the use of platinum-based adjuvant chemotherapy, there was only a marginal increase in overall survival and a 15% decrease in relapse. With the advents of immunotherapy and epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), the landscape of adjuvant treatment in completely resectable NSCLC is changing. Postoperative radiotherapy can be beneficial to patients who underwent surgical resection in certain clinical settings. In addition, new biomarkers that predict efficacy of EGFR TKI and immunotherapy as adjuvant treatment are also necessary. In this review, recent updates in adjuvant treatment in resectable NSCLC were briefly explained.

A decision support framework for postoperative radiotherapy in patients with pathological N2 non-small cell lung cancer

INTRODUCTION

Postoperative radiotherapy (PORT) plays a highly controversial role in pathological N2 (pN2) non-small cell lung cancer (NSCLC) disease. Recent studies reveal that not all patients can benefit from PORT. Further research is needed to identify predictors of PORT.

METHODS

A total of 1044 pathologic stage T1-3N2M0 NSCLC patients were analyzed. Risk factors of distant metastasis were identified by the log-rank tests and the multivariable Cox models. We integrated risk factors of distant metastasis and our previously published loco-regional recurrence (LRR) related prognostic index into a decision support framework (DSF) to predict the outcomes of PORT. An independent cohort was used to validate the DSF.

RESULTS

We defined patients with more than two of three identified LRR-related features (heavy cigarette smoking history, clinical N2 status, and more than four positive lymph nodes) as a high LRR risk group. We found the high-intermediate-risk histological type (with micropapillary and/or solid components) was associated with a higher risk of distant metastasis (HR=1.207, 95% CI 1.062 to 1.371, P=0.0129), but not LRR. We built the DSF by combining these two types of features. Patients were stratified into four groups by using the DSF. PORT significantly improved OS only in the subgroup without high-risk histological features (without micropapillary or solid components) and with a high risk for LRR (three-year OS: 66.7% in the PORT group vs. 50.2% in the non-PORT group; P=0.023).

CONCLUSIONS

A particular pN2 subgroup with a high risk of LRR and without micropapillary or solid components could benefit from PORT.

Postoperative radiotherapy for patients with completely resected stage IIIA-N2 non-small cell lung cancer: opt-in or opt-out

The role of adjuvant radiotherapy in completely resected pIIIA-N2 non-small cell lung cancer (NSCLC) has long been debated. Evidence from previous retrospective and prospective studies showed that postoperative radiotherapy could reduce the incidence of local recurrence and prolong disease-free survival, while two recently reported randomized controlled trials (lung ART and PORT-C) both demonstrated no survival benefit of postoperative radiotherapy. The great gap between our knowledge and reality has made us rethink the value of postoperative radiotherapy. In this mini review, we elaborate on the role of postoperative radiotherapy in completely resected pIIIA-N2 NSCLC.