COLORECTAL ADENOCARCINOMA IN CROHNS-DISEASE - A RETROSPECTIVE HISTOLOGIC-STUDY

PURPOSE: The aim of this study was to review all histopathologic secti ons from surgical specimens with inflammatory bowel disease and colore ctal carcinoma fired at this hospital between 1951 and 1996. METHOD: A total of 40 surgical (n = 39) or autopsy (n = 1) colon or colorectal specimens were reviewed. Internationally accepted histologic criteria were strictly applied to differentiate Crohn's disease (CD), ulcerativ e colitis (UC), and indeterminate colitis (IC). RESULTS: Of the 40 spe cimens with inflammatory bowel disease and carcinoma, 22 (55 percent) had CD, 16 (40 percent) had UC, and the remaining 2 (5 percent) had IC . Males accounted for 72.7 percent or 16 of the 22 patients with color ectal carcinoma in CT) and for 68.7 percent or 11 of the 16 patients w ith carcinoma in UC. Both patients with IC and carcinoma were males. T he median age of patients at diagnosis was as follows: CD, 20 (range, 7-68) years; UC, 23 (range, 5-21) years. In IC, the age was 61 and SI years, respectively. The median disease duration (before detection of colorectal cancer) was as follows: CD, 18.5 (range, 1-45) years; UC, 1 9 (range, 6-38) years. For cases with IC, it was 13 and 13 years, resp ectively. Median age of patients at cancer diagnosis was as follows: C D, 48 (range, 21-78) years; UC, 49 (range, 21-81) years. Ages at cance r diagnosis in IC were 68 and 81 pears. Colorectal carcinoma tend to d evelop among relatively young patients with CD and UC. Mucinous adenoc arcinomas accounted for approximately one-third of the carcinomas affe cting CD. Thirty percent of old specimens (before the end of 1982) had in fact cat-cinema complicating CD and not UC (the latter being the d iagnosis appearing in old pathologic reports). During a time lapse of 38 pears (i.e., between 1951 and 1989), only 11 cases of colorectal CD with carcinoma (i.e., 0.2 cases/year) were found, but as many as 11 d uring the past 6.5 years (i.e., 1.7 cases/year) have been diagnosed. O nly 42.3 percent (11/26) of cases with colorectal inflammatory bowel d isease and carcinoma operated on between 1951 and the end of 1989 had Crohn's colitis but as many as 78.6 percent (11/14) of those operated on between 1990 and May 1996 had Crohn's colitis. Review of the Litera ture indicated that 64.8 percent or 191 of the 295 cases of colorectal carcinomas in CD so far reported occurred in the past 6.5 pears. It w ould seem as if the risk of colorectal carcinoma in Crohn's colitis ha s increased in later pears. CONCLUSIONS: 1) Reports on cancer frequenc y in UC based on old histopathologic records should be subjected to cr itical. histologic re-evaluation; 2) carcinoma in Crohn's colitis has increased at this hospital, particularly since 1990; 3) the surveillan ce program strategy used in patients with long-standing UC at this hos pital should also embrace patients with Crohn's colitis.