Cowden's disease, or multiple hamartoma syndrome, is a rare condition classified recently as a hereditary preneoplastic syndrome. Multiple orocutaneous hamartomas are associated with involvement of other organ systems, including fibrocystic breast disease and breast carcinoma, goiter, thyroid cancer, gastrointestinal polyps, and endometrial carcinoma. We describe a patient with Cowden's disease who underwent extensive gastroenterological work-up and review other cases in the literature.