Comparative effectiveness of primary radiotherapy versus surgery in oropharyngeal squamous cell carcinoma in elderly patients: A SEER-Medicare analysis.

Abstract

e18124 Background: Primary radiotherapy (RT) and primary surgery (PS) are considered equally viable local therapy modalities for oropharyngeal squamous cell carcinoma (OPSCC). The relative efficacy and toxicity of these competing therapies are often debated, and treatment choice is based on a paucity of comparative data. Methods: Eligible individuals were elderly patients in the SEER-Medicare registry diagnosed with OPSCC between 2000 and 2011. Patients were categorized as receiving either primary RT +/- chemotherapy, or PS +/- adjuvant RT or chemoradiotherapy (CRT). Overall survival (OS) was analyzed using Cox multivariable analysis (MVA). Risks of gastrostomy dependence (GD), esophageal stricture (ES), and osteoradionecrosis (ORN) at 1 year were determined through claims and analyzed using logistic regression. Results: A total of 3,804 patients (70% RT, 30% PS) were included in this cohort. At a median follow-up of 24.2 months, median and 2-year OS were 37.9 months and 61.1%, respectively. Patients treated with RT and PS experienced 2-year OS and median survival outcomes of 58.5%/34.9 months and 66.4%/48.0 months, respectively (p < 0.001). In early-stage OPSCC, MVA found older age, unmarried status, increasing comorbidity, SEER region, tumor site, and no prior PET associated with inferior OS; treatment was not associated with OS. For locally advanced OPSCC, increasing age, unmarried status, increasing comorbidity, lower income, tumor site, higher stage, no prior PET, and RT alone (HR = 1.24 for RT alone vs. PS, p = 0.0020, whereas HR 1.08 for CRT vs. PS, p = 0.1955) were associated with inferior OS. Multivariable predictors of ES (9.5% of cohort) were SEER region, grade, and PS treatment (OR = 1.03 and 0.70 for RT and CRT vs. PS, p = 0.015). Independent predictors of GD at 6 months (21.5%) included married status, smoking, tongue site, advanced stage, and CRT treatment (OR = 1.13 and 2.30 for RT and CRT vs PS, p < 0.001). The 1 year risk of ORN was 3.8% and not associated with treatment. Conclusions: Without a clearly dominant modality in elderly patients, local therapy decisions for OPSCC must be individualized to each patient’s disease and functional status.