Efficacy and cost of high-frequency IGRT in elderly stage III non-small-cell lung cancer patients.

BackgroundHigh-frequency image-guided radiotherapy (hfIGRT) is ubiquitous but its benefits are unproven. We examined the cost effectiveness of hfIGRT in stage III non-small-cell lung cancer (NSCLC).MethodsWe selected stage III NSCLC patients ≥66 years old who received definitive radiation therapy from the Surveillance, Epidemiology, and End-Results-Medicare database. Patients were stratified by use of hfIGRT using Medicare claims. Predictors for hfIGRT were calculated using a logistic model. The impact of hfIGRT on lung toxicity free survival (LTFS), esophageal toxicity free survival (ETFS), cancer-specific survival (CSS), overall survival (OS), and cost of treatment was calculated using Cox regressions, propensity score matching, and bootstrap methods.ResultsOf the 4,430 patients in our cohort, 963 (22%) received hfIGRT and 3,468 (78%) did not. By 2011, 49% of patients were receiving hfIGRT. Predictors of hfIGRT use included treatment with intensity-modulated radiotherapy (IMRT) (OR = 7.5, p ConclusionhfIGRT did not affect clinical outcomes in elderly patients with stage III NSCLC but did increase radiation cost. hfIGRT deserves further scrutiny through a randomized controlled trial