Chemotherapy versus best supportive care in patients with advanced biliary tract carcinoma: A propensity score-matched analysis.

Abstract

316 Background: Although chemotherapy is endorsed by various guidelines for advanced biliary tract cancer (BTC), the evidence of chemotherapy over best supportive care (BSC) is limited. However, prospective randomized trial with BSC control arm is unrealizable. The aim of this study is to investigate the survival benefit of chemotherapy over BSC in patients with advanced BTC. Methods: Advanced BTC patients with good performance status (ECOG 0-2) were eligible for the study. Data were retrospectively collected in the four tertiary cancer centers and analyzed through propensity score-matching (PSM) to minimize bias. Of 810 enrolled patients cohort, 206 patients received BSC only without any palliative chemotherapy, versus 604 patients were treated with chemotherapy. PSM analysis was performed using the following variables: Age, ECOG, Carcinoembryonic antigen (CEA) and White blood cell (WBC). The sample size of each group was 171 patients after PSM. Overall survival (OS) was compared between the two groups using the Kaplan-Meier method and prognostic factors were investigated by cox proportional regression. Results: In pre-PSM analysis, the OS for chemotherapy group and BSC group, respectively, were as follows: total population, 15.2 vs 7.0 months (p < 0.001); metastatic disease, 12.7 vs 6.2 months (p < 0.001); locally advanced disease, 28.0 vs 13.4 months (p = 0.01); ECOG 0-1, 17.0 vs 8.8months (p < 0.001); CA 19-9 < 100, 13.9 vs 5.9 months (p = 0.001) and CA 19-9 ≥ 100, 11.8 vs 6.0 months (p < 0.001). In post-PSM 171 pair analysis, the respective OS for chemotherapy group and BSC group were depending on the prognostic factors as follows : total population, 12.7 vs 7.0 months (p < 0.001); metastatic disease, 10.9 vs 8.1 months(p= 0.001); locally advanced disease, 20.8 vs 15.9 months (p = 0.416); ECOG 0-1, 14.5 vs 11.5 months(p < 0.001); CA 19-9 < 100, 12.8 vs 12.7 months (p = 0.472) and CA 19-9 ≥ 100, 11.8 vs 8.2 months (p < 0.001). Conclusions: Chemotherapy improved OS in advanced BTC with good performance status compared BSC. However, the survival benefit was not demonstrated in BTC patients with locally advanced disease or with lower serum CA19-9 tumor marker.