THE OUTCOME OF FAMILIAL ADENOMATOUS POLYPOSIS IN THE ABSENCE OF A POLYPOSIS REGISTRY

From 1964 to 1990, 70 patients with familial adenomatous polyposis wer e diagnosed at an institution without a polyposis registry. Those with symptoms at diagnosis were older (mean 34 v. 24 years) and more often had large-bowel cancer (7/30 v. 1/30, 23% v. 3%). The introduction of systematic screening significantly increased the number of cases diag nosed annually, from 2,3 to 5 per year, reduced the median age at diag nosis from 29 to 21 years and increased the proportion of cases diagno sed without symptoms from 52% to 90%. A colectomy with an ileorectal a nastomosis achieved a low incidence of rectal cancer at 20 years (1/15 , 7%) despite imperfect follow-up and annual sigmoidoscopy in only 40% . However, bowel cancer caused at least 35% of all deaths and 62% of d eaths due to a known cause. A registry which maintained a screening pr ogramme should therefore prevent most large-bowel cancers and improve the life expectancy of patients with familiar adenomatous polyposis wh o are managed at this institution. It might also refine the current me thod of screening by sigmoidoscopy alone, by facilitating the use of o phthalmoscopy and blood tests for DNA markers.