| Abstract: |
The optimal radiation dose for patients with inoperable, locally advanced non–small-cell lung cancer ineligible for concurrent chemoradiation remains unclear. In the present retrospective, multivariate analysis of 336 patients treated with sequential chemoradiation or definitive radiation only, a radiation dose > 66 Gy was superior to a radiation dose < 60 Gy for the endpoints of overall survival and local failure. Introduction: The optimal radiation dose for locally advanced non–small-cell lung cancer (NSCLC) is not known for patients who receive sequential chemoradiation (CRT) or definitive radiotherapy (RT) only. Our objective was to determine whether a benefit exists for radiation dose escalation for these patients. Materials and Methods: The patients included in our retrospective analysis had undergone RT for NSCLC from 2004 to 2013, had not undergone surgery, and received a dose ≥ 50.0 Gy. Patients who received concurrent CRT were excluded from the analysis, leaving 336 patients for analysis. The primary outcomes were overall survival (OS), local failure (LF), and distant failure (DF). Results: On multivariate analysis, after adjusting for age, Karnofsky performance status, gross tumor volume, and treatment modality, patients treated with a radiation dose > 66 Gy had significantly improved OS compared with those treated with < 60 Gy (hazard ratio [HR], 0.58; 95% confidence interval [CI], 0.39-0.87; P =.008). After adjusting for smoking history and radiologic tumor size, patients treated with a radiation dose > 66 Gy had a significantly decreased risk of LF compared with those treated with < 60 Gy (HR, 0.59; 95% CI, 0.38-0.91; P =.02). The radiation dose was not an independent prognostic factor of DF on multivariate analysis. Conclusion: When controlling for tumor volume and/or dimensions and other independent prognostic factors, patients with locally advanced NSCLC who were not candidates for concurrent CRT benefited from a radiation dose > 66 Gy versus < 60 Gy with improved OS and reduced LF. An increased radiation dose did not appear to affect the incidence of DF. © 2017 Elsevier Inc. |
