Natural history of metastatic biliary tract cancer (BTC) patients with good performance status (PS) who were treated with only best supportive care (BSC)

Background: Although chemotherapy is widely recommended for patients with metastatic biliary tract cancer, the natural course of these patients, especially those with good performance status who are indicated for chemotherapy, is not known. Methods: We retrospectively reviewed patients with metastatic or locally advanced biliary cancer who were diagnosed at six cancer centers. Patients were eligible if they had good performance (ECOG 0-2) and no history of any treatment for cancer. The primary objective was to evaluate the survival time of patients with advanced biliary cancer with good performance who were untreated. Results: Of the 1677 patients, 204 met the inclusion criteria. The median age and overall survival were 72.0 years and 7.1 months. Overall survival (months) by location was 4.7 for intrahepatic, 9.7 for extrahepatic, 4.4 for gallbladder and 11.2 for ampulla of vater cancer. In subgroup analysis, overall survival of locally advanced biliary cancer was 13.8 months and that of patients with normal carcinoembryonic antigen/carbohydrate antigen 19-9 was 10.6 months. In multivariate analysis, variables that were associated with poor prognosis were metastatic biliary cancer [hazard ratio 2.19 (P = 0.001)], high baseline carcinoembryonic antigen level (defined as > 4.0 ng/ml) [hazard ratio 1.51 (P = 0.024)] and high baseline carbohydrate antigen 19-9 level (defined as > 100 U/ml) [hazard ratio 1.93 (P = 0.001)]. Conclusions: Advanced biliary tract cancer with good performance status showed modest survival without any treatment. Furthermore, subgroup analysis showed that patients with normal carbohydrate antigen 19-9 or carcinoembryonic antigen level or locally advanced status had favorable survival. Further studies comparing the outcome of chemotherapy with that of best supportive care in patients with unresectable biliary tract cancer are warranted.