A randomized trial of oral 5-fluorouracil versus placebo as adjuvant therapy in colorectal cancer Dukes' B and C: results after 5 years observation time.

A double-blind randomized trial of daily oral 5-fluorouracil (5 mg kg-1 bodyweight) for 3 months versus placebo as adjuvant therapy to surgical treatment of colorectal cancer Dukes' B and C was conducted. In total 421 patients were randomized; 198 patients with Dukes' B, 159 with Dukes' C and 64 were referred to a limited resection group. The distribution of prognostic variables was similar in both groups indicating the absence of any bias and the efficacy of the randomization. Disease-free interval and survival time were analysed as end points. After 5 years of follow-up of all patients there was no significant difference between treatment or placebo group in the total material or the subgroups regarding either of the end points. There was no difference in localization of first recurrence between treated and control group. A high withdrawal of therapy was found in the 5-FU group (40 per cent) and in the placebo group (13 per cent).