Which of the following colonic polyps is not pre-malignant?
Answer is A (Juvenile Polyps): Juvenile Polyps is the single best answer of choice. Juvenile polyps (sporadic), in general occur singly and being hamaomatous lesions have no malignant potential-Robbins Juvenile polyps are benign polyps - Sabiston Pathologically hamaomas are considered benign and devoid of malignant potential. However hamaomatous polyps associated with Autosomal dominant hereditary syndromes have now been established to carry a small malignant potential (Rare) Juvenile Polyps are benign but Juvenile Polyps in association with Juvenile Polyposis syndrome carry small malignant potential. The juvenile polyps in Juvenile polyposis syndrome are usually hamaomas but they may contain adenomatous elements and may progress to adenomas. This syndrome is associated with increased risk of (9 - 25%) of colorectal cancer. Mutation in Tumor supressor gene SMAD4 are believed to cause 50 % of Repoed cases. Sporadic Hamaomatous polyps are benign but Hamaomas in association with Peutz Jaghers Syndrome may carry a small malignant potential. Peutz Jaghers Syndrome is associated with increased risk (2-10%) of cancer in the intestinal tract. (Sabiston) The malignant potential of polyps associated with Peutz Jaghers Syndrome is small - CSDT. Review of Hereditary gastrointestinal polvposis syndromes Hereditary autosomal dominantQ gastrointestinal polyposis syndromes High Malignant Potential Q (histologically adenomas Q) Rare (small) Malignant Potential Q (histological/ hamaomas e) Syndrome Distribution Associated Syndrome Distribution Associated Familial colonic Large intestine None Peutz SI > LI > Stomach Mucocutaneous Polyposis Gardner's syndrome Large intestine > small intestine Osteomas Lipomas Fibromas Jagher's syndrome pigmentations Tumours of ovary, Breast, pacnreas, endometrium Turcot's syndrome Large intestine Epidermal cyst Ampullaty Ca Desmoid Brain Tumours Juvenile polyposis syndrome LI > SI > Stomach Various congenital abnormalities
Juvenile polyps
Hamaomatous polyps associated with PeutzJeghers Syndrome
Villous adenomas
Tubular adenomas