A Multicenter Phase II Study of Gemcitabine plus S-1 Chemotherapy for Advanced Biliary Tract Cancer

Gemcitabine (GEM) plus cisplatin (CDDP) chemotherapy has been used worldwide as the standard first-line treatment for advanced biliary tract cancer (BTC). A phase II trial has also suggested promising activity of GEM plus S-1 chemotherapy against advanced BTC. The aim of this study was to evaluate the efficacy and safety of GEM plus S-1 chemotherapy in patients with advanced BTC.

The eligibility criteria were as follows: histologically-proven BTC, unresectable or recurrent disease, ECOG performance status (PS) 0-1 regardless of previous treatment. Gemcitabine was administered intravenously at the dose of 1,000 mg/m² over 30 min on days 1 and 8, and S-1 was administered orally at doses of 60/80/100 mg/day based on the BSA, from day 1 to day 14, every 3 weeks. The primary endpoint was the response rate according to RECIST, ver. 1.1, and the secondary endpoints were the frequency/severity of toxicities, progression-free survival (PFS) and overall survival (OS).

A total of 38 patients were enrolled between August 2008 and November 2011. There were 19 men and 19 women, with a median age of 66 years (range=44-81 years). Seven patients had a previous history of first-line or adjuvant chemotherapy after surgery. The PS was 0 and 1 in 30 and 7 patients, respectively. The treatment response was classified as partial response in 6 patients (15.8%) and as stable disease in 18 patients (47.4%). The median PFS and OS were 5.8 and 15.9 months, respectively. The toxicity was generally mild, and the most common grade 3/4 toxicities were leukopenia (31.6%), neutropenia (36.8%), nausea/vomiting (2.6%), and diarrhea (2.6%). There was one treatment-related death due to interstitial pneumonia.

Our study revealed that gemcitabine plus S-1 chemotherapy was well-tolerated and exhibited favorable antitumor activity in patients with advanced BTC.