Adenocarcinoma developing at an ileostomy: report of a case and review of the literature.

Primary adenocarcinoma of a permanent ileostomy is a rare and unusual complication. We report a case of primary adenocarcinoma arising at an ileostomy site 46 years after total proctocolectomy for Crohn's colitis. In addition, we performed a literature search and found 36 such cases reported. Based on the results of this case and literature review, we concur with the previously reported theory that the etiology of this phenomenon is likely the result of colonic metaplasia in the ileal mucosa, which eventually progresses to carcinoma. Common presenting symptoms include a bleeding, friable mass, difficulty fitting the stomal appliance, and bowel obstruction. Once confirmed by biopsy, appropriate surgical en bloc excision and stomal relocation is the mainstay of therapy. Lymph node metastasis occurs in 19 percent of patients and survival is at least 85 percent. Adjuvant therapy may be of additional benefit. Patient education is important for early detection as the lesion typically appears an average of 27 years after the original operation.