Conditional Survival of Gallbladder Cancer After Curative‐Intent Surgery: Impact of Disease Stage, Surgical Extent, and Adjuvant Therapy

INTRODUCTION: Gallbladder cancer is a rare but aggressive malignancy with poor prognosis even after curative-intent surgery. Conventional survival estimates provide fixed probabilities from diagnosis and fail to reflect the evolving prognosis of patients who have already survived several years. Conditional survival (CS) offers time-updated prognostic information, but evidence in gallbladder cancer remains limited. METHODS: We retrospectively analyzed 641 patients who underwent curative-intent resection for gallbladder cancer at a tertiary referral center (2005-2019). Five-year conditional overall survival (COS) and conditional recurrence-free survival were estimated up to 5 years postoperatively. Analyses were stratified by age, stage, comorbidity, surgical extent, and adjuvant therapy. RESULTS: Baseline 5-year COS was 69.4% and increased to 74.0% among patients surviving 5 years. Stage III patients showed the largest improvement (45.9%-69.4%), whereas Stage I patients remained stable. In Stage II-III disease, extended cholecystectomy was associated with improved COS (63.2%-74.3%), while simple cholecystectomy showed a decline (65.7%-48.0%). Adjuvant therapy was associated with greater COS improvement (50.4%-69.2%) than no adjuvant therapy. Older patients (≥ 70 years) and those with diabetes showed poorer outcomes. CONCLUSION: CS provides a dynamic framework for prognostication in gallbladder cancer and may support risk-stratified follow-up.