Optimal timing of reoperation for postoperatively diagnosed T2 gallbladder cancer: a retrospective multicenter cohort study.

BACKGROUND: Although the frequency of incidental diagnosis of gallbladder cancer (GBC) after cholecystectomy is increasing and further resection is necessary for stage T2 GBC or higher, the optimal timing of reoperation remains debated. The objective of the current study was to compare short- and long-term outcomes according to the interval between initial cholecystectomy and reoperation. METHODS: Among 802 patients who underwent extended cholecystectomy for T2 GBC between November 2004 and October 2022 at five tertiary referral centers in Korea, 148 underwent reoperation after initial cholecystectomy and were included in this study. Patient outcomes were compared according to the interval between initial cholecystectomy and reoperation. RESULTS: Patients were divided into three groups according to the interval between initial cholecystectomy and reoperation: <4 weeks (group A), 4-8 weeks (group B), and >8 weeks (group C). Operation time (A vs. B vs. C: 225.3±124.7 vs. 179.4±85.6 vs. 169.3±56.4 min, P<0.001) and estimated blood loss {median (interquartile range), 100 [100-300] vs. 100 [100-100] vs. 100 [87.5-100] cc, P=0.03} were greater in group A. The median follow-up duration was 52 months. Five-year recurrence-free survival was worst in group C (64.0% vs. 83.6% vs. 58.9%, P=0.02). In multivariable analysis, long interval [hazard ratio (HR) 5.74, P=0.002] and residual disease (HR 5.42, P<0.001) were independent risk factors for recurrence. CONCLUSIONS: The optimal interval between initial cholecystectomy and reoperation for postoperatively diagnosed T2 GBC is 4-8 weeks. Early reoperation is associated with worse intraoperative outcomes, and delayed reoperation is associated with higher risk of recurrence.