Definitive chemotherapy and radiotherapy in patients with stage II non-small cell lung cancer: A population-based outcomes study.

Abstract

There is a paucity of data on non-surgical outcomes specific to stage II non-small cell lung cancer (NSCLC) patients receiving definitive chemotherapy and radiation therapy (CRT). This study reports population-based outcomes for this subgroup, and investigates a radiation dose-response for overall survival. The National Oncology Data Alliance (NODA), a merging of multiple tumor registries maintained by Elekta(®) medical systems, was queried for stage II patients and CRT. Only curative cases (RT doses ≥59 Gy) were included. Both sequential and concurrent CRT were allowed. Univariate and Cox multivariate techniques were used to assess factors significant for overall survival. These factors included: gender, age, race, radiation dose, radiation total treatment time, stage, histology, tumor size, and chemotherapy sequence. A total of 568 patients were included in the analysis, with a median follow-up of 12.9 months for surviving patients. Patients were treated between 2004 and 2014. Median survival was 20.5 months (95% confidence interval (CI) 18-23 months), with 16% patients alive at 5 years. Only gender was found to be significantly associated with survival in the Cox model. Although median survival was higher in patients receiving greater than 60 Gy (21 months, 95% CI 18-24 moths) compared to 59-60 Gy (16.5 months 95% CI 10-23 months), this was not statistically significant (p=0.6). This is the first report on outcomes for stage II NSCLC patients receiving CRT as definitive therapy. Survival approximates stage III CRT patients from historical phase III trials. As an increasing aging population may parallel a rise in medically inoperable stage II patients, this study can provide useful information when reviewing treatment options.