LOWER GASTROINTESTINAL MALIGNANCY IN CROHNS-DISEASE

An increased incidence of carcinoma of the small bowel and colon has b een described in patients with Crohn's disease. Tumours arising in the rectum and anus are reported less often. Between 1940 and 1992, of so me 2500 patients with Crohn's disease seen at this hospital, 15 are kn own to have developed carcinoma of the lower gastrointestinal tract. M alignancy occurred in the colon in two patients, in the upper two thir ds of rectum in one, in the lower third of rectum in seven, and in the anus in five. The 12 patients with carcinoma arising in the anus or l ower rectum had longstanding severe anorectal Crohn's disease, which i ncluded a stricture in four, fistula in four, proctitis in one, absces s in two, and enlarged anal skin tags in one. The development of malig nancy in patients with Crohn's disease may apply particularly to those with chronic complicated anorectal disease.