Supplementary Material for: Gemcitabine plus Cisplatin versus Capecitabine plus Cisplatin as First-Line Chemotherapy for Advanced Biliary Tract Cancer: A Retrospective Cohort Study

<b><i>Background and Aim:</i></b> Gemcitabine plus cisplatin (GP) is a standard chemotherapy option for patients with advanced biliary tract cancer (BTC). We compared the efficacy and safety of capecitabine plus cisplatin (XP) versus GP in advanced BTC. <b><i>Methods:</i></b> The records of all patients treated with GP or XP chemotherapy for unresectable, metastatic, or recurrent BTC at the National Cancer Center between December 2001 and August 2012 were reviewed retrospectively. Patients with histologically confirmed intrahepatic cholangiocarcinoma, gallbladder cancer, or extrahepatic cholangiocarcinoma were enrolled. <b><i>Results:</i></b> Of the 344 patients enrolled, 127 received GP and 217 received XP. At a median follow-up time of 8.9 months, the median time to progression was longer in the GP group than in the XP group (5.6 vs. 4.7 months), but the difference was not statistically significant (p = 0.081). The median overall survival (OS) was 8.4 months (95% CI 6.2-10.7) in the GP group and 7.6 months (95% CI 6.8-8.7) in the XP group (p = 0.024), with statistical significance retained following multivariate analysis (HR 0.72; 95% CI 0.527-0.987; p = 0.004). Grade 3/4 toxicities were significantly more frequent in the GP group than in the XP group (40.9 vs. 24.9%, p = 0.002). <b><i>Conclusions:</i></b> GP was superior to XP in prolonging OS, despite increasing the rate of grade 3/4 adverse events.