Adenomyoma of the jejunum.

Adenomyoma of the small intestine is an extremely rare condition characterized by abnormal glandular structures surrounded by smooth muscle. We report a case of adenomyoma of the jejunum. The patient was a 61-year-old female with cancer of the sigmoid colon and multiple liver cysts, who was sent to the operation room for exploratory laparotomy and sigmoidectomy. At surgery, a polypoid lesion was incidentally found in the lower jejunum, which was resected. On histologic examination, the morphologic features were typical of adenomyoma. However, new histopathological and immunohistochemistry features are described here, providing evidence that adenomyoma of the jejunum is a form of intestinal epithelial hamartoma.