Stage-tailored role of extrahepatic bile duct resection in gallbladder cancer: limited value in T2 disease and potential oncologic role in selected T3/T4 cases

The oncological value of extrahepatic bile duct resection (EBDR) in gallbladder cancer (GBC) remains controversial, particularly regarding its stage-specific benefit. We retrospectively analyzed 64 patients with pathologically confirmed T2–T4 GBC who underwent curative-intent R0 resection between 1985 and 2018. EBDR was selectively performed based on intraoperative findings, including lymph node metastasis, positive cystic duct margins, or direct duodenal invasion. Patients were stratified by tumor stage (T2 vs. T3/T4). Disease-free survival (DFS), overall survival (OS), and recurrence patterns were evaluated. In the overall cohort, EBDR was not associated with significant differences in DFS or OS. Among T2 patients ( n = 42), survival outcomes were comparable between the EBDR( +) and EBDR(–) groups (5-year OS: 87.5% vs. 91.0%, P = 0.63; 5-year DFS: 87.5% vs. 92.4%, P = 0.61). In contrast, among T3/T4 patients ( n = 22), EBDR was associated with significantly improved 5-year OS (78.8% vs. 11.4%, P = 0.0023) and a favorable trend toward improved 5-year DFS (43.6% vs. 9.1%, P = 0.069), despite a higher incidence of lymph node metastasis and lymphatic invasion (72.7% vs 24.3%, P = 0.043) in the EBDR( +) group. Local recurrence occurred exclusively in the EBDR(–) group (22% vs. 0%). Routine EBDR appears unnecessary for T2 GBC. In T3/T4 disease, EBDR was associated with better OS and a lower observed frequency of local recurrence; however, these exploratory findings require validation in larger cohorts.