<prompt> On colonoscopy which of the following is highly malignant -Single pedunculated polypMultiple flat polyp about hundredsMultiple pedunculated polypSolitary flat polyp  <response>: Also referred to as Bannayan-Zonana syndrome, Ruvalcaba-Riley smith syndrome, and Bannayan-Riley-Ruvalcaba syndrome. Characterized by hamartomatous polyposis and OLD HM-2.OLD HM-2 : Ocular abnormalities, Lipomas, Developmental abnormalities. Hashimotos thyroiditis, Hyperpigmentation of penis. Macrocephaly, Mental retardation. No increased risk of colorectal carcinoma, other gastrointestinal or extraintestinal malignancy. 