Background In phase II studies, irinotecan is active in metastatic colorectal cancer, but the overall benefit has not been assessed in a randomised clinical trial.
Methods Patients with proven metastatic colorectal cancer, which had progressed within 6 months of treatment with fluorouracil, were randomly assigned either 300-350 mg/m 2 irinotecan every 3 weeks with supportive care or supportive care alone, in a 2:1 ratio.
Findings 189 patients were allocated irinotecan and supportive care and 90 supportive care alone. The mean age of the participants was 58•8 years; 181 (65%) were men and 98 (35%) were women. WHO performance status was 0 in 79 (42%) patients, 1 in 77 (41%) patients, and 2 in 32 (17%) patients. Tumour-related symptoms were present in 134 (71%) patients and weight loss of more than 5% was seen in 15 (8%) patients. With a median follow-up of 13 months, the overall survival was significantly better in the irinotecan group (p=0•0001), with 36•2% 1-year survival in the irinotecan group versus 13•8% in the supportive-care group. The survival benefit, adjusted for prognostic factors in a multivariate analysis, remained significant (p=0•001). Survival without performance-status deterioration (p=0•0001), without weight loss of more than 5% (p=0•018), and pain-free survival (p=0•003) were significantly better in the patients given irinotecan. In a quality-of-life analysis, all significant differences, except on diarrhoea score, were in favour of the irinotecan group.
Interpretation Our study shows that despite the sideeffects of treatment, patients who have metastatic colorectal cancer, and for whom fluorouracil has failed, have a longer survival, fewer tumour-related symptoms, and a better quality of life when treated with irinotecan than with supportive care alone.