Abstract
Colitic cancer associated with Crohn's disease has recently been recognized, and the case of a patient who developed anal fistula cancer after 18 years had passed is presented. A 52-year-old man had been diagnosed with Crohn's disease at age 34 years. At age 46 years, he had undergone transverse colostomy for left colon stenosis and exacerbation of anal bleeding due to a refractory anal fistula. He presented to a local clinic with exacerbation of anal pain, computed tomography (CT) showed a perianal low-density area, and blood tests showed an elevated CA19-9 level. Lower gastrointestinal endoscopy showed multiple stenoses in the colon and rectum, and a circumferential stenosis 7 cm from the anus. This was identified as adenocarcinoma by anal biopsy, and the patient was referred to our department. Preoperative enema tests identified an enterocolic fistula at the anal opening side of the double-orifice colostomy in the right-sided transverse colon, as well as complete stenosis of the hepatic flexure. Abdominoperineal resection of the rectum, total prostatectomy/cystostomy, and colectomy/ileostomy were performed. Choosing the appropriate surgical procedure in accordance with the pathological condition, including curative treatment, is key to the treatment of anal fistula cancer associated with Crohn's disease, and this case is reported along with a discussion of the literature.
