A Comparison of Radiation Techniques in Patients Treated With Concurrent Chemoradiation for Stage III Non-Small Cell Lung Cancer

PURPOSE: The standard of care in management of patients with good performance status and unresectable stage III non-small cell lung cancer (NSCLC) therapy is concurrent chemoradiation. Newer techniques such as intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT) are replacing 3-dimensional conformal radiation (3DCRT) despite low-quality evidence of improved outcomes. We used population-based data to examine survival outcomes by radiation technique. METHODS AND MATERIALS: A population-based retrospective cohort of patients with stage III NSCLC treated with concurrent chemoradiation from 2009 to 2017 in Ontario were identified. The primary outcome was a comparison of overall survival among 3DCRT, IMRT, and VMAT, calculated using the Kaplan-Meier method and compared using log-rank test. Cox regression was used to investigate effect of radiation type on overall survival adjusted for other covariates. RESULTS: A total of 3872 patients were treated with 3DCRT (n = 1178), IMRT (n = 1847), or VMAT (n = 847). A decline in 3DCRT and increase in VMAT use were observed over time. Median survival in months was 21.2 (95% confidence interval [CI], 20.0-22.8) for 3DCRT, 23.9 (95% CI, 22.3-25.6) for IMRT, and 24.9 (95% CI, 22.5-27.4) for VMAT, but these differences were not statistically significant (P = .06). CONCLUSIONS: Our study demonstrates that survival is not compromised in patients receiving IMRT or VMAT (compared with 3DCRT). Thus, given the potential dosimetric advantages associated with these techniques, VMAT and IMRT are recommended for the management of patients with stage III NSCLC.