Screening and Prevention



The process of colonic carcinogenesis probably evolves over years. Neoplastic polyps and early localized carcinomas can be resected readily with excellent long-term results. There is therefore considerable interest in screening certain popu­lations for colonic polyps and carcinomas using annual testing for occult fecal blood and periodic (every three to five years] proctosigmoidoscopy beginning at age 40 to 50. The finding of occult blood in the stool should be followed up rigor­ously with radiological or endoscopic examina­tion of the entire colon. There is still some debate about the cost effectiveness of this approach in the general population. Quite clearly, however, individuals known to be at high risk for devel­oping carcinoma of the colon (familial polyposis syndrome, prior colonic polyp or cancer, long­standing ulcerative colitis) should be screened even more frequently than the schedule noted above.