Colorectal carcinoma in ulcerative colitis is decreasing in Scandinavian countries

A total of 31 cases with Ulcerative Colitis (UC) and colorectal carcinoma were retrieved from the files of the Karolinska Hospital, Stockholm between 1951 and 1998. Sections from 16 colectomy specimens (operable cases) and 15 biopsies obtained at laparotomy (inoperable cases), were available for the study. Of the 31 patients reported here, 22 (71%) were 49 years of age or younger at the time of surgery for carcinoma. In comparison only 47 (5.5 %) of the 855 colorectal carcinomas without UC reported in the Stockholm area in 1990 were 49years of age oryounger. When this hospital was a referral Center (1951 through 1969) 18 cases of carcinoma in UC were operated between 1951 and 1960 (1.8 patients/year), but only 4 between 1961 and 1969 (0.44 patients/year). During the surveillance period of 29 years (1970 to March 1998) only 9 patients (0.31 cases/year) were found to have carcinoma complicating UC. Notably, 8 of the 9 patients were operated on between 1970 and December 1989 (0.42 patients/year), but only one case between January 1990 and March 1998 (0.11 patients/year). The data presented indicate that the frequency of carcinoma cases in pancolitics has decreased at this hospital, not only during the referral period, from 1.8 patients/year during the 50's to 0.40 patients/year during the 60's, but also during the surveillance period (from 0.44 patients/year/during the 70's and 80's to 0.11 patients/year between 1990 and March 1998). This, despite the incidence of UC in the Stockholm County remained stable for the past 40 years (4.2 to 5 patients/10(5) inhabitants) and that the population in the Stockholm County has steady increased since 1950. A review of the present literature indicated that the ris for colorectal carcinoma in pancolitics is presently decreasing, not only in Sweden but also in other Scandinavian countries.