In a review of 1037 patients with colorectal cancers, there were 32 patients below the age of 40 years (3 percent). Rectal bleeding and abdominal pain were the most common presenting symptoms. The average delay between the onset of symptoms and treatment was 6.5 months. An analysis of tumors according to Dukes' staging revealed no significant difference between young and elderly patients. The younger patients had a greater frequency of mucinous and poorly differentiated carcinoma. When compared by clinical staging, however, the young patient did as well or better than his older counterpart. Clinical staging was the most important prognostic factor, irrespective of age. No inherent difference was found in the virulence of the cancer in the young, and five-year survival rates were not significantly different in young and old patients (59 percent vs. 49 percent).