Benign:- Hyperplastic polyps→ Most common; generally smaller and predominantly located in rectosigmoid region- Inflammatory polyps→ Due to mucosal erosion in inflammatory bowel disease.- Hamartomous polyps→ Associated with Peutz-Jeghers syndrome and juvenile polyposis.

Malignant potential- Adenomatous polyps→ Neoplastic, via chromosomal instability pathway with mutations in APC and KRAS.→ Colonoscopy: pedunculated / sessile→ Histology: tubular / tubulovillous / villous- Serrated polyps→ Characterized by CpG island methylator phenotype. Defect may silence MMR gene (DNA mismatch repair) expression. Mutations lead to microsatellite instability and mutations in BRAF. “Saw-tooth” pattern of crypts on biopsy.