Prognostic impact of combination therapy with gemcitabine and cisplatin plus S-1 and subsequent conversion surgery for initially unresectable upper biliary tract cancers

Purpose and background: For the past decade, there have been few chemotherapy options for unresectable biliary tract cancer (BTC). Recently, however, combination therapy with gemcitabine and cisplatin plus S-1 (GCS) has been identified as a promising strategy. This retrospective study analyzes the clinical results of GCS therapy and subsequent conversion surgery (CS).

Method: We analyzed the clinical data of 60 consecutive patients who received GCS therapy for unresectable upper BTC at our university hospital during the 5 years between September, 2018 and December, 2022.

Results: All patients received GCS therapy as first-line chemotherapy. The response rate was 33.9% and subsequent CS was performed in 35.0%. Of the patients who underwent CS, 81% required more than bisectionectomy of the liver with extrahepatic bile duct resection. The median overall survival of the patients who received GCS therapy and underwent subsequent CS was significantly longer than that of the patients who received GCS therapy alone (28.0 months vs. 12.4 months, respectively; p < 0.001). A decrease in the CA19-9 level 1 month after chemotherapy and RECIST PR were independent positive predictors of CS, whereas unresectable gallbladder cancer and pretreatment ALBI grade 3 were negative predictors of CS.

Conclusion: GCS therapy and subsequent CS may contribute to the longer term survival of patients with unresectable upper BTC.