Radiation therapy improves survival for unresectable postpneumonectomy lung tumors

Abstract

Background: Additional resection for cancer in the single lung is often considered a prohibitive risk. The role of radiation therapy (RT) in this patient population is less clear with very limited available data. In this study, we sought to examine patients with postpneumonectomy lung cancer not amenable to surgery, identify factors associated with receiving RT, and determine the impact of RT on survival outcomes.

Methods: The Surveillance, Epidemiology, and End Results (SEER) database (1988-2013) was queried for patients with inoperable contralateral lung cancer after pneumonectomy. Univariate and multivariate analyses were performed to identify factors associated with the receipt of RT. Survival outcomes were examined using the Kaplan-Meier method.

Results: In total, 191 patients with inoperable postpneumonectomy lung cancer were included. RT was delivered to 122 (63.9%) patients; 69 (36.1%) patients did not receive RT. On multivariate analysis, disease stage was identified as the only predictor associated with receipt of RT (P < 0.001). The median overall survival (OS) and disease-specific survival (DSS) for patients receiving RT were higher than those for patients who did not receive RT (25 versus 8 mo and 29 versus 10 mo, respectively; P < 0.001). Similarly, patients who received RT had a higher 3-y OS (34% versus 14%, P < 0.001) than those who did not receive RT. On subset analysis, survival benefit with RT was observed in patients with all tumor size groups, and there was a trend toward superior survival in patients with stage I/II disease, who received RT compared with those who did not. On multivariate Cox regression analysis, RT use was independently associated with decreased hazards of death after adjusting for other factors (HR, 0.539; P < 0.001).

Conclusions: Based on our analysis of the Surveillance, Epidemiology, and End Results (SEER) database, RT is associated with improved outcomes in inoperable patients with a contralateral lung cancer after pneumonectomy compared with observation alone.