A solitary Peutz-Jeghers-type hamartomatous polyp of the rectum: report of a case and review of the literature.

A solitary Peutz-Jeghers-type polyp of the rectum in a 64-year-old Japanese man is reported. Barium enema and endoscopic examination revealed a solitary polypoid lesion in the rectum. The polyp was pedunculated, and measured 2 x 1.5 x 1.5 cm. The patient had neither mucocutaneous pigmentation nor a family history of gastro-intestinal polyposis. Histopathologically, this polyp had an arborizing muscular network originating from the muscularis mucosa, and was covered by well organized mucosa with epithelial hyperplasia. The smooth muscle bundles in the polyp were thicker than those seen in Peutz-Jeghers syndrome, but their network was not as complex.