Hospital Volume and Operative Mortality in Pancreaticoduodenectomy and Hepatectomy: Analysis of the National Clinical Database in Japan

BACKGROUND/PURPOSE: This study evaluated the association between institutional advanced hepatobiliary-pancreatic (HBP) surgical volume and operative mortality for pancreaticoduodenectomy (PD) and advanced hepatectomy using data from the Japanese National Clinical Database. METHODS: Patients undergoing PD or advanced hepatectomy between 2018 and 2021 were identified. Hospital volume was defined as the mean annual number of advanced HBP procedures performed at each institution. Volume-mortality associations were assessed using thin-plate spline regression with hospital volume as a continuous variable, followed by categorical analyses using four predefined groups (≤ 19, 20-29, 30-49, and ≥ 50 cases/year). The primary outcome was the operative mortality. RESULTS: We analyzed 47 088 patients undergoing PD and 27 358 undergoing hepatectomy. Mortality decreased with increasing institutional advanced HBP surgical volume for both procedures and plateaued at approximately 50 annual procedures. Compared with 30-49-case institutions, ≤ 19-case hospitals had significantly higher adjusted mortality for PD and hepatectomy, whereas ≥ 50-case hospitals had significantly lower mortality. CONCLUSIONS: Higher institutional advanced HBP surgical volume was associated with lower operative mortality for both procedures. Although both procedures appeared to achieve stable outcomes at similarly high institutional volumes, their volume-mortality curves differed in shape, suggesting the value of incorporating procedure-specific considerations into future quality assessment frameworks.