Outcomes of minimally invasive surgery for gallbladder tumorous lesions before and after insurance approval of laparoscopic gallbladder bed resection in Japan

Purpose: The nationwide insurance approval of laparoscopic gallbladder bed resection (GBR) in April 2022 accelerated the adoption of minimally invasive surgery (MIS) for gallbladder cancer in Japan. This study compared surgical outcomes for gallbladder tumorous lesions before and after insurance coverage. Methods: This retrospective single-center study included 85 patients who underwent surgery for gallbladder tumorous lesions between 2018 and 2024. Patients were divided into a before insurance coverage (BIC, n=45) and after insurance coverage (AIC, n=40) group. Surgical procedures included laparoscopic cholecystectomy, total-layer cholecystectomy, GBR, and extrahepatic bile duct resection. Results: The proportion of malignant lesions was similar between groups. In suspected T1 cases, secondary GBR was required only in the BIC group, whereas no additional surgery was needed in the AIC group. Laparoscopic GBR was significantly more frequent in the AIC group for suspected T2/T3a disease. R0 resection rates and recurrence patterns were comparable between groups, with no regional lymph node recurrence observed in this cohort. Among patients postoperatively diagnosed with malignant tumors, Kaplan–Meier analysis demonstrated no significant difference in overall survival between the two groups. Lymph node metastasis was the only significant risk factor for recurrence, whereas the adoption of MIS was not associated with an increased risk of recurrence. Conclusion: Following insurance approval, a majority of gallbladder tumorous lesions were managed using MIS without an apparent compromise in oncological outcomes and with fewer staged additional resections. However, reliable preoperative differentiation between benign and malignant lesions remains challenging, and the retrospective singlecenter design of this study represents an important limitation.