Impact of provider volume on front-line chemotherapy guideline compliance and overall survival in elderly patients with advanced ovarian cancer

Purpose. We sought to evaluate whether provider volume or other factors are associated with chemotherapy guideline compliance in elderly patients with epithelial ovarian cancer (EOC). Methods. We queried the SEER-Medicare database for patients >= 66 years, diagnosedwith FIGOstage II-IV EOC from 2004 to 2013 who underwent surgery and received chemotherapy within 7 months of diagnosis. We compared NCCN guideline compliance (6 cycles of platinum-based doublet) and chemotherapy-related toxicities across provider volume tertiles. Factors associated with guideline compliance and chemotherapy-related toxicities were assessed using logistic regression. Overall survival (OS) was compared across volume tertiles and Cox proportional-hazards model was created to adjust for case-mix. Results. 1924 patients met inclusion criteria. The overall rate of guideline compliance was 70.3% with a significant association between provider volume and compliance (64.5% for low-volume, 72.2% for medium-volume, 71.7% for high-volume, p = .02). In the multivariate model, treatment by low-volume providers and patient age >= 80 years were independently associated with worse chemotherapy-guideline compliance. In the survival analysis, there was a significant difference in median OS across provider volume tertiles with median survival of 32.8 months (95%CI 29.6, 36.4) low-volume, 41.9 months (95%CI 37.5, 46.7) medium-volume, 42.1 months (95%CI 38.8, 44.2) high-volume providers, respectively (p < .01). After adjusting for case-mix, low-volume providers were independently associated with higher rates of mortality (aHR 1.25, 95%CI: 1.08, 1.43). Conclusions. In a modern cohort of elderly Medicare patients with advanced EOC, we found higher rates of non-compliant care and worse survival associated with treatment by low-volume Medicare providers. Urgent efforts are needed to address this volume-outcomes disparity. (C) 2020 Elsevier Inc. All rights reserved.