<prompt> The most pre-cancerous condition for carcinoma colon is -Familial polyposisHamartomatous polypsJuvenile polypsHyperplastic polyps  <response>: A polyp is a tumorous mass that protrudes into the lumen of the gut.GIT polyps may be of following typesA. Non-neoplastic polypsi Hyperplastic polypsMost common polyp of the large intestineHas no malignant potential.ii Hamartomatous polypsa Juvenile polyp No malignant potential except in Juvenile polyposis syndromeb Retention polyp No malignant potential except in Juvenile polyposis syndromec Peutz Jeghers syndrome Polyps are not premalignant but patients are at increased risk of developing extraintestinal carcinoma of pancreas, breast, lung, ovary and uterus.B Neoplastic polypsi Adenomatous polypTubular adenoma Has malignant potential villous more than tubular.Villous adenoma Has malignant potential villous more than tubular.ii Familial polyposis FAP syndromeFAP can be further classified intoa Classic FAP syndromeTypically develop 500 to 2500 colonic adenoma.A minimum of 100 polyps adenoma is necessary for a diagnosis of classic FAP.b Attenuated FAPFewer polyps average, 30Risk of cancer development is usually around 50.c Gardner syndromePolyps multiple osteoma epidermal cyst Fibromatosis.d Turcot syndromePolyps CNS tumor medulloblastoma, glioblastoma.iii Hereditary nonpolyposis colorectal cancer HNPCC syndromeAlso, known as Lynch syndrome.Characterized by an increased risk of colorectal cancer and extraintestinal cancer particularly of the endometrium. 