Prognostic factors in patients with advanced biliary tract cancer treated with first-line gemcitabine plus cisplatin: retrospective analysis of 740 patients

Biliary tract cancer (BTC) is a heterogeneous group of diseases comprising intrahepatic and extrahepatic cholangiocarcinoma and gallbladder cancer. Although gemcitabine plus cisplatin (GEMCIS) was established as the standard first-line chemotherapy based on the ABC-02 trial, more data are needed to define the clinical course of BTC and its prognostic factors with the standard GEMCIS treatment. Between April 2010 and June 2016, 740 patients with histologically documented cholangiocarcinoma and gallbladder cancer were treated with first-line GEMCIS in Asan Medical Center, Seoul, Korea. In 389 patients with measurable disease (53%), the objective response rate was 13% (n = 50) and there was no significant difference between primary tumor sites (p = 0.45). With a median follow-up duration of 27.3 months (95% CI 24.2-30.5), the median PFS and OS were 5.2 months (95% CI 4.7-5.6) and 10.4 months (95% CI 9.6-11.2), respectively. In multivariate analysis, male gender (female versus male, hazard ratio [HR] 0.83), baseline CA 19-9 level (elevated versus normal, HR 1.31), initially metastatic disease (versus locally advanced disease, HR 1.92), poor performance status (2 versus 0-1, HR 1.45), and measurable disease by RECIST criteria (versus non-measurable, HR 1.40) were significantly associated with a poorer OS (all p < 0.05). Our retrospective analysis of a large number of patients in a real-world setting found comparable efficacy outcomes to the ABC-02 trial. The prognostic factors identified here may help to predict clinical outcomes and design future clinical trials for advanced BTC.