A prospective feasibility study of one-year administration of adjuvant S-1 therapy for resected biliary tract cancer in a multiinstitutional trial (Tokyo Study Group for Biliary Cancer: TOSBIC01)

Although surgery is the definitive curative treatment for biliary tract cancer (BTC), outcomes after surgery alone have not been satisfactory. Adjuvant therapy with S-1 may improve survival in patients with BTC. This study examined the safety and efficacy of 1 year adjuvant S-1 therapy for BTC in a multi-institutional trial.