Impact of surgical volume on outcomes of laparoscopic adrenalectomy for benign adrenal tumors: A Japanese nationwide database analysis.

Objective: To analyze the recent status of laparoscopic adrenalectomy for benign adrenal tumors, focusing on the relationship between the number of surgeries and complication rates per facility.

Methods: Data were obtained from the Diagnosis Procedure Combination database, covering surgeries performed between April 2012 and March 2020. The inclusion criteria were laparoscopic adrenalectomy for benign adrenal tumors. Basic characteristics and outcomes, including anesthesia time, blood transfusion, and medical costs, were analyzed. The facilities were divided into five categories in increments of five adrenalectomies per year. The relationship between the number of surgeries per facility and complication rates was analyzed using the Cochran-Armitage trend test and chi-square tests with the Holm method applied for multiple comparisons.

Results: A total of 15 174 laparoscopic adrenalectomies for benign adrenal tumors were performed across 543 facilities during the 9-year study period. The number of adrenalectomies performed annually was <5, 5-9, 10-14, 15-19, ≥20 in 434 (79.9%), 58 (10.7%), 28 (5.2%), 12 (2.2%), and 11 (2.0%) facilities, respectively, showing that only 51 facilities (9.4%) conducted 10 or more surgeries per year. The overall complication rate was 9.1%. A trend was demonstrated showing that facilities with a higher number of surgeries per year had reduced complication rates. Facilities with 20 or more surgeries per year had the shortest anesthesia times and the lowest medical costs. No significant differences were found in blood transfusion rates or in-hospital mortality.

Conclusion: Laparoscopic adrenalectomy for benign adrenal tumors can be performed at lower complication rates in facilities with a higher number of surgeries.