Purpose: Although chemotherapy is recommended by various guidelines for advanced biliary tract cancer (BTC), the evidence supporting its use over best supportive care (BSC) is limited. The aim of this study was to investigate the survival benefit of chemotherapy over that of BSC in advanced BTC patients.
Materials and methods: Advanced BTC patientswith a good performance status (Eastern CooperativeOncologyGroup [ECOG] 0-2) were eligible for the study. Data were retrospectively collected from four tertiary cancer centers and analyzed using propensity score matching (PSM). Of the 604 patients enrolled, 206 received BSC and 398 received chemotherapy. PSM analysis was performed using the following variables: age, ECOG status, carcinoembryonic antigen (CEA) level, white blood cell level, albumin level, total bilirubin level, and aspartate aminotransferase level. The sample size of each group was 164 patients after PSM. Median survival was compared between the two groups by using the Kaplan-Meier method, and prognostic factors were investigated using Cox proportional regression analysis.
Results: In post-PSM analysis, the respective median survival for the chemotherapy and BSC groups was dependent on the following prognostic factors: total population, 12.0 months vs. 7.5 months (p=0.001); locally advanced disease, 16.7 months vs. 13.4 months (p=0.490); cancer antigen 19-9 ≤ 100 IU/mL, 12.7 months vs. 10.6 months (p=0.330); and CEA ≤ 3.4 ng/mL, 17.1 months vs. 10.6 months (p=0.052).
Conclusion: Chemotherapy improved overall survival of patients with advanced BTC who had a good performance status. However, this survival benefit was not observed in BTC patients with locally advanced disease or with lower tumor marker. Individualized approach is needed for initiation of palliative chemotherapy in advanced BTC.
Keywords: Biliary tract neoplasms; Observation; Propensity score; Survival analysis; Drug therapy.