CARCINOMA ARISING IN ANORECTAL FISTULAS OF CROHNS-DISEASE

PURPOSE: Anorectal fistulas are commonly associated with Crohn's disea se. Carcinoma arising in an anal fistula in the absence of Crohn's dis ease occurs rarely. Carcinoma arising in an anorectal fistula of Crohn 's disease is likewise rare and is the subject of this article. METHOD S: We have seen eight cases in seven patients. Four of these were squa mous carcinoma and three were adenocarcinoma. Details of these seven p atients are presented. RESULTS: Two deaths in the four patients with s quamous carcinoma and one in the two patients with adenocarcinoma with adequate follow-up suggest a poorer prognosis in both types of malign ancy than when these lesions occur without Crohn's disease. CONCLUSION : Carcinoma does arise in the midst of the anorectal fistulas and absc esses of Crohn's disease. Carcinoma arising in a Crohn's disease fistu la can be very difficult to diagnose. Examination may be limited by pa in, stricture, or induration of the perianal and perineal tissues. Exa mination under anesthesia can also overlook the lesion. Diagnostic exa mination under anesthesia yields increases with biopsies or curettage of the fistulous tracts.