CLINICOPATHOLOGICAL CHARACTERISTICS OF COLORECTAL-CARCINOMA COMPLICATING ULCERATIVE-COLITIS

This study examined three features associated with colorectal carcinom a complicating ulcerative colitis: (a) the distribution of 157 cancers in 120 patients with ulcerative colitis treated at St Mark's Hospital between 1947 and 1992; (b) the frequency at which dysplasia was found at a distance from the tumour in 50 total proctocolectomy specimens i n which an average of 27 histology blocks were reviewed, and (c) the f ive year survival rate according to Dukes's stage and participation in a surveillance programme. Of 157 carcinomas, 88 (56%) occurred in the rectosigmoid, 19 (12%) in the descending colon or splenic flexure, an d 50 (32%) in the proximal colon. Among the 120 patients, the rectum o r sigmoid colon contained cancer in 81 (67.5%). Dysplasia was detected in 41 of 50 reviewed proctocolectomy specimens (82%). Dysplasia dista nt to a malignancy occurred in 37 (74%); two were classified indefinit e, probably positive, 19 were low grade, and 16 were high grade; in 18 specimens there was an elevated dysplastic lesion. Survival was relat ed to the Dukes's stage: about 90% of patients with Dukes's A or B can cer were alive at five years. The five year survival of 16 patients in whom cancer developed during surveillance was 87% compared with 55% o f 104 patients who did not participate in surveillance (p = 0.024).