Screening results in a family cancer clinic: five years experience

We present our experience so far of screening individuals referred to the Cancer family clinic at St. Mark's Hospital from 1986, with the results of the follow-up of these individuals. 651 individuals from 436 families were offered colonoscopic surveillance at five-yearly intervals. The median age at which the examination was performed was 41 years. Families were subdivided according to family history; 15.8% conformed to the Amsterdam criteria for hereditary nonpolyposis colorectal cancer (HNPCC). The pathological findings were correlated with the type of pedigree; abnormalities were more often found in males than females (30% of colonoscopies in males revealed adenomas, and 17% in females), and adenoma prevalence increased with age. Adenoma prevalence (27% v.s. 21% at all ages, and 38% v.s. 25% in individuals over the age of 35y.), multiple adenomas and the proportion of proximally sited adenomas were all higher in HNPCC families; however, dysplasia and villous or large adenomas were not more common in individuals from HNPCC families. Four of the 7 carcinoma detected were in HNPCC families (3% v.s. 0.6%).