Gardner syndrome

**Definition:** Gardner syndrome develops adenomatous polyps throughout the gastrointestinal tract, accompanied by extracolonic manifestations, including periampullary adenomas, papillary carcinoma of the thyroid, hepatoblastoma, osteomas of the mandible and skull, epidermal cysts, and desmoid tumours. Gardner syndrome is a term used to refer to patients in whom these extraintestinal features are unusually prominent.