Brooke Army Medical Center Tumor Registry records from 1947 through 1980 were reviewed. One hundred forty of 819 patients with colorectal cancer were aged 40 or less. The 5 year survival rate was 35 percent and the 10 year survival rate 32 percent. The predominant presenting symptoms were bleeding, pain and change of bowel habits. The median duration of symptoms was 3 months. There were no Dukes'A patients. The 5 and 10 year survival rates in 19 Dukes' B patients were 67 percent. Thirty-three Dukes' C patients had 5 and 10 year survival rates of 37 and 30 percent, respectively. In 42 Dukes' D patients, however, there were no 5 year survivors, and the mean length of survival was only 10 months. Our findings support previous surveys which have concluded that stage at the time of diagnosis, rather than symptoms, duration or patient age, is the most accurate prognostic factor.