S-1 and gemcitabine as an outpatient-based regimen in patients with advanced or metastatic pancreatic cancer

Objective: The standard beneficial chemotherapy proved for patients with pancreatic cancer is a regimen containing gemcitabine. Novel oral fluoropyrimidine, S-1, can be added to gemcitabine to improve the efficacy of chemotherapy and to provide better convenience for patients. We aimed to evaluate the efficacy and safety of S-1 plus gemcitabine combination chemotherapy as a first-line treatment in patients with locally advanced or metastatic pancreatic cancer. Methods: Patients with histologically confirmed, bidimensionally measurable advanced/metastatic pancreatic cancer were eligible for the study. Chemotherapy consisted of S-1 (30 mg/m² p.o. bid from Day 1 to 14) and gemcitabine (1000 mg/m² on Days 8 and 15) every 3 weeks based on the results of a previously reported Phase I trial. Treatment was repeated until disease progression or unacceptable toxicity occurred. Results: From January 2005 to August 2007, 22 patients were enrolled. Median age was 62 years (range, 50-73). Nineteen patients (86.3%) had metastases and of these, 11 patients (57.9%) had multiple liver metastases. The overall response rate was 27.3% (95% CI, 8.7-45.9), with a partial response in six patients, stable disease in nine (40.9%) and progressive disease in seven (31.8%). With a median follow-up of 25.4 months, the median time to progression and overall survival were 4.6 (95% CI, 2-7.2 months) and 8.5 months (95% CI, 6.8-10.1 months), respectively, and 1-year survival rate was 27.3%. S-1 plus gemcitabine was well tolerated. Grade 3/4 hematological adverse events were neutropenia (9.1/9.1%) and anemia (4.5/0%). Non-hematological adverse events were mainly gastrointestinal events. Twenty patients (91%) received chemotherapy on an outpatient basis. Conclusions: Combination chemotherapy of S-1 plus gemcitabine appears to be active and well tolerated as first-line treatment in patients with advanced/metastatic pancreatic cancer.