ENDOSCOPIC SCREENING OF RELATIVES OF PATIENTS WITH COLORECTAL-CANCER

Background-The risk of colorectal cancer is higher among relatives of those affected. The neoplastic yield reported from screening such indi viduals varies enormously between studies and depends on the age and s trength of the family history of those screened. Aims-To ascertain the neoplastic yield of endoscopic screening of first degree relatives of patients with colorectal cancer by age and familial risk. Subjects-A total of 330 individuals with a family history of colorectal cancer. M ethod-Endoscopic screening conducted according to a protocol. Results- Adenomas were found in 12%, and adenomas larger than 1 cm in 8%, of '' high risk'' individuals screened primarily by colonoscopy. Of those wi th neoplasia, 26% had lesions at or proximal to the splenic flexure. N eoplasia was found in 9.5% of individuals at lower familial risk, scre ened primarily by 60 cm flexible sigmoidoscopy, 4% of whom had neoplas ia larger than 1 cm in size or cancer. Neoplastic yield was greatest i n the fourth and fifth decades in those at highest risk, but increased with age in those at lower risk. Conclusions-For individuals with two or more first degree relatives, or relatives who have developed color ectal cancer at a young age, colonoscopy appears to be the only satisf actory method of screening, but 60 cm flexible sigmoidoscopy may be us eful in those at lower levels of risk.