The impact of hospital volume on racial disparities in resected rectal cancer

Background Although high volume centers (HVC) equate to improved outcomes in rectal cancer, the impact of surgical volume related to race is less defined. Methods Patients who underwent surgical resection for stage I-III rectal adenocarcinoma were divided into cohorts based on race and hospital surgical volume. Outcomes were analyzed following 1:1 propensity-score matching using logistic, Poisson, and Cox regression analyses with marginal effects. Results Fifty-four thousand one hundred and eighty-four (91.5%) non-Black and 5043 (8.5%) Black patients underwent resection of rectal cancer. Following 1:1 matching of non-Black (N = 5026) and Black patients, 5-year overall survival (OS) of Black patients was worse (72% vs. 74.4%, average marginal effects [AME] 0.66, p = 0.04) than non-Black patients. When compared to non-Black patients managed at HVCs, Black patients had worse OS (70.1% vs. 74.7%, AME 1.55, p = 0.03), but this difference was not significant when comparing OS between non-Black and Black patients managed at HVCs (72.3% vs. 74.7%, AME 0.62, p = 0.06). Length of stay was longer among Black and HVC patients across all cohorts. There was no difference across cohorts in 90-day mortality. Conclusions Although racial disparities exist in rectal cancer, this disparity appears to be ameliorated when patients are managed at HVCs.