Adenocarcinoma in a Blind Loop of the Ileum 53 Years After an Ileotransversostomy Procedure

BACKGROUND Primary small bowel cancer is a rare malignancy; the common histopathological types are carcinoid and adenocarcinoma. Inflammatory bowel diseases and familial adenomatous polyposis are known risk factors for small bowel cancer. Additionally, cases of surgery-induced small bowel adenocarcinoma are sometimes reported after ileostomy. CASE REPORT A 84-year-old woman, who had undergone ileotransversostomy for intestinal obstruction due to postoperative adhesion following appendectomy at the age of 31 years, was referred to our hospital for further examination after experiencing abdominal pain in the right lower quadrant for 2 weeks. Laboratory data showed elevated serum levels of carcinoembryonic antigen (CEA, 102.9 ng/ml) and carbohydrate antigen 19-9 (CA19-9, 104 U/ml). Enhanced computed tomography (CT) revealed a 10-cm mass in the terminal ileum and a distention of the ileum and colon in the blind loop, with retention of feces. The patient was suspected of having ileal cancer by preoperative examination; therefore, right hemicolectomy with en bloc resection was performed. The tumor was histopathologically diagnosed as a well-differentiated and mucinous adenocarcinoma of the ileum. At over 12 months after surgery, tumor recurrence had not been observed. CONCLUSIONS Difficulties in diagnosis can cause delays in treatment and lead to poor prognosis, mainly because tumors in the small bowel rarely cause clinical symptoms. Adenocarcinoma of the ileum should be considered in postoperative patients with ileotransversostomy.