Screening results in a family cancer clinic: five years experience.

We present our experience so far of screening individuals referred to the Cancer famil 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 colonscopic surveillance at five-yearly intervals. The median age at which the examination was performed was 41 years. Families were subdvided according to family history; 15.8% conformed to the Amsterdam criteria for hereditary non-polyposis 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 prevulence increased with age