Cancer surveillance of patients with longstanding ulcerative colitis: a clinical, endoscopical, and histological study.

An eight year endoscopical and histological cancer surveillance programme comprising 71 patients with ulcerative colitis is presented. Forty one patients had total colitis and 30 substantial colitis. Mean duration of the disease was 19.7 years (range 9-46 years). An average of 2.6 colonoscopies per patient in the total colitis group were carried out, and at least two biopsies were taken at 10 locations in the colon. In the total colitis group, seven had either low (four), or high grade dysplasia (two), or Dukes' A cancer (one). In the group with substantial colitis two patients with low grade dysplasia were found. Dysplasia or cancer leading to operation was found above the rectum in four of five operated patients, all having had total colitis for 25 to 44 years. The dysplasia and cancer findings at the colonoscopy preceding surgery corresponded well with the surgical specimens. In three operated patients a sequence of dysplasia development was recorded. With the exception of long duration and dysplasia, nothing in the clinical course distinguished the operated cases. Using this surveillance programme prophylactic colectomy can be limited to patients in a high risk group developing dysplasia. The risk of missing a cancer before it becomes incurable seems to be low.