A Retrospective Study of S-1 Monotherapy as Second-line Treatment for Patients with Advanced Biliary Tract Cancer

OBJECTIVE: Gemcitabine has been widely used, and cisplatin plus gemcitabine is considered as standard first-line chemotherapy for patients with advanced biliary tract cancer. However, no standard therapy was established following the progression to gemcitabine-containing first-line therapy. As S-1 monotherapy as second-line chemotherapy is still not well known in a practical setting this study aimed to clarify its efficacy and safety. METHODS: We retrospectively reviewed 55 consecutive patients who received S-1 monotherapy as second-line chemotherapy after failure of a gemcitabine-containing regimen at our institution from September 2007 to March 2011. The inclusion criteria were preserved organ function and an Eastern Cooperative Oncology Group performance status of 0-2 and without massive ascites or pleural effusion. S-1 was administered orally twice a day at a dose of 40 mg/m(2) for 28 days, followed by 14 days of rest. RESULTS: Fifty-one patients were selected for this analysis. The overall response rate was 4.0% and the disease control rate was 38.0%. The median survival time was 6.0 months and the median progression-free survival was 2.3 months. Adverse events were generally mild, and treatment-related death did not occur. In the subgroup analysis, overall survival was significantly shorter in the patients with peritoneal dissemination and those who had shown no response to the first-line chemotherapy (P= 0.033 and 0.023, respectively). CONCLUSIONS: S-1 monotherapy as the second-line chemotherapy for patients with gemcitabine-refractory advanced biliary tract cancer is also feasible in a practical setting and its efficacy is almost the same as in the previous prospective study.