A phase II study was performed to evaluate 1-(2-tetrahydrofuryl)-5-fluorouracil and uracil (UFT) and leucovorin as first-line chemotherapy in European patients with advanced gastric cancer. From 38 patients, 25 were evaluable for response and 36 for toxicity. Patients received UFT at 300 mg/m(2)/day for 28 days, every 35 days and leucovorin at 90 mg/day on an identical schedule. Overall response rate was 10.5% (95% confidence interval (CI): 3.7-22.5%) in intent-to-treat analysis and 16% (95% CI: 5.7-33%) in evaluable patients. Grade 3-4 common toxicity criteria (CTC) toxicities were diarrhoea (28%; 10/36), nausea (11%; 4/36), vomiting (8%; 3/36) and asthenia (11%; 4/36). 23 patients in 44% (42/96) of the courses had to skip days of treatment due to toxicity or to non-compliance. In conclusion, UFT+leucovorin has a definitive, but low, efficacy in advanced gastric cancer patients. Toxicities were mainly gastrointestinal and treatment needs to be withheld if grade 2 diarrhoea occurs.