[S-1 monotherapy for pancreatic cancer]

Early and late phase II studies of S-1 were conducted for the treatment of metastatic pancreatic cancer. In both trials, S-1 was administered at a dose of 80 mg/m2/day. One course consisted of consecutive administration of S-1 for 28 days, followed by 14 days of rest. This regimen was repeated every 6 weeks until the occurrence of progressive disease or unacceptable toxicities. The early phase II study demonstrated a response rate of 21.1% with a median survival time of 5.6 months in 19 patients. The major drug-related adverse events were gastrointestinal toxicities like nausea, and anorexia, though most of them were tolerable and reversible. Other treatment-related adverse events, like ileus, colitis, and abdominal distension, were less frequent. The late phase II study confirmed favorable responces with a mild toxicity profile in 40 evaluable patients. S-1 is active and well tolerated in patients with metastatic pancreatic cancer. Randomized trials are warranted to determine the effectiveness of S-1 for the treatment of pancreatic cancer.