Surgical practice patterns and outcomes in T2 and T3 gallbladder cancer: a population-based study

BACKGROUND: The extent of resection required in advanced gallbladder cancer is controversial. We aimed to describe the management and outcomes in patients with resected stage T2 and T3 gallbladder cancer. METHODS: In this population-based study, all T2 and T3 gallbladder cancer cases from Jan. 1, 2002, to Mar. 31, 2012, were identified from the Ontario Cancer Registry; pathology reports were linked and abstracted. The type of resection was classified as extended (cholecystectomy + liver resection, with or without bile duct resection) or simple (cholecystectomy only). We used Kaplan–Meier survival analysis to model time to death and evaluated factors associated with overall survival using the Cox proportional hazards regression model. RESULTS: A total of 370 patients were included, 232 with T2 disease and 138 with T3 disease. The proportions who underwent extended resection were 24.1% (56/232) and 37.0% (51/138), respectively. The unadjusted 5-year overall survival rates for simple and extended resection were 39.7% and 49.5%, respectively, for T2 disease (p = 0.03), and 13.5% and 22.8%, respectively, for T3 disease (p = 0.05). In adjusted analysis, extended resection significantly improved overall survival among patients with T2 disease (hazard ratio [HR] 0.51, 95% confidence interval [CI] 0.30–0.97), whereas higher grade of differentiation, presence of lymphovascular invasion and positive lymph nodes led to worse survival. Extended resection was not associated with improved survival in the T3 group; however, in subgroup analysis stratified by lymph node status, a trend toward improved overall survival with extended resection was seen in node-negative patients (HR 0.20, 95% CI 0.03–1.06). CONCLUSION: Extended resection improved overall survival in T2 disease regardless of nodal status but appeared most beneficial in node-negative T3 disease. The finding that extended resection was offered only to a small proportion of eligible patients highlights the need for improved knowledge translation at national surgical meetings.