A Case of Primary Mature Teratoma of the Rectum

A mature teratoma is a tumor composed of normal derivatives of all three germ layers, and usually occurs in ovaries, testes, or mediastinum. Mature teratoma of the gastrointestinal tract occurs less frequently, and case reports of primary mature teratoma of the rectum have not been published much. Here, we report a 65-year-old woman patient presented with lower abdominal discomfort. Colonoscopy revealed a pedunculated polypoid tumor arising from the rectum with hairs on its surface, and endoscopic ultrasound revealed an exophytic pattern bulging from the serosa. The tumor was removed surgically and confirmed histologically as a benign, primary mature teratoma of the rectum.