Between 1975 and 1990, 525 patients underwent resection of colorectal cancer in our unit. Of these, 38 had tumour invading adjacent structures and underwent an extended resection. Overall, there were 67 cases treated palliatively. Of these, three were in the group of 38 having an extended resection. When the groups of radical not extended (n = 423) and radical extended resections (n = 35) were compared, respective values for mortality (1.9% vs 0) and morbidity (12.8% vs 11.3%) were not different. Respective local recurrence rates (13% vs 26%) were significantly greater after extended resection. Five-year survival after extended resection was 30%, no different from the general survival rate for standard resections for T2-3 node-positive tumours. Extended resection is thus a safe and important approach for locally advanced tumours.