Cowden's syndrome or multiple hamaoma syndrome is a rare autosomal dominant syndrome characterised by orocutaneous hamaomatous tumours, gastrointestinal polyps, abnormalities of the breast, thyroid gland and genitourinary system. The gastrointestinal polyps are generally benign and malignant transformation is seen very rarely. Ref: Harrisons Principles of Internal Medicine, 18th Edition, Page 3384