The hairy polyp: a benign teratoma of the colon.

A 76-year-old female presented with bright red rectal bleeding. Endoscopic evaluation revealed a polypoid lesion sprouting hair in the sigmoid colon. Histologically the resected polyp was composed of elements of all three germ layers, fulfilling the criteria for a teratoma. The differential diagnosis of this benign polyp and its significance are discussed.