Adjuvant chemotherapy for resected biliary tract cancers: a systematic review and meta-analysis

Introduction: The use of adjuvant treatment (AT) in resected biliary tract cancers (BTC) is still controversial. No efficacy comparison has been performed between chemotherapy (CT) and chemoradiotherapy (CTRT). A systematic review of the available evidence regarding adjuvant chemotherapy (AC) in resected BTC was performed. Methods: PubMed, EMBASE, Web of Science, SCOPUS and The Cochrane Library databases were searched for relevant articles published. Only studies including at least 50 patients affected by tumors of gallbladder, intrahepatic, perihilar, and distal bile ducts were considered. Data were pooled using a random-effects model. The primary endpoint of the study was overall survival (OS). Results: Thirty studies were analyzed with a total of 22,499 patients, 3967 of whom received AC. Eleven cohorts included Western patients and 19 were Asiatic. Surgeries were classified as R0 with negative margins, R1 with positive microscopic and R2 with positive macroscopic margins. Weighted mean OS difference among experimental (AC) and control arm was 4.3 months (95% CI 0.88–7.79, P = 0.014). AC reduced the risk of death by 41% (Hazard ratio [HR] = 0.59, 95% CI 0.49–0.71; P < 0.001). Conclusions: AC administration gives an OS benefit in resected BTC. The results of prospective randomized studies are awaited in order to define the standard AT in BTC