The oral fluoropyrimidines have proved to be active in colorectal cancer in Japan and, recently, in the United States and Europe. Continuous oral administration simulates protracted fluorouracil (5-FU) continuous intravenous infusion. The purpose of this trial was to evaluate the tolerability and potential advantages of oral treatment for colorectal cancer in the elderly. The main inclusion criterion was age over 72 years. Patients were treated with UFT (tegafur plus uracil) 400 mg/24 hours (fixed doses) continuously plus folinic acid 45 mg/24 hours until toxicity. If grade 3 or 4 toxicity appeared, treatment was stopped until recovery. From September 1994 to November 1996, 126 patients were included. For the analysis in November 1996, 77 patients were evaluable for response, toxicity, and survival. The patients, including 34 women and 43 men, had a median age of 74 years (range, 72 to 82 years of age). The Karnofsky performance status was 60% to 80% for 41 patients and 90% to 100% for 36 patients. Liver metastasis was present in 48% of the cases, and 42% were locoregional and peritoneal. Toxicity was mild, with only one patient having grade 3 thrombocytopenia, 11 (14%) grade 3 or 4 nausea/vomiting, seven (9%) grade 3 or 4 diarrhea, and one grade 3 mucositis. Four patients (5%) had complete responses and nine (11.6%) partial responses, for an objective response rate of 16.9% (95% confidence interval, 9% to 27%). Twenty-two patients (28.6%) showed no change. The number of patients in whom disease did not progress (ie, patients with complete plus partial responses plus those with stable disease) was 35 (45.4%) (95% confidence interval, 34% to 57%). With a maximum follow-up of 24 months, the median actuarial survival is 14.4 months. The number without disease progression and the median survival in this preliminary analysis suggests that this schedule is a moderately effective, comfortable, treatment with only mild toxicity, that can be recommended for use in the elderly, and it warrants further study.