Inverted hyperplastic polyps of the colon

An unusual form of hyperplastic polyp of the colon is described in which endophytic growth can simulate adenoma or carcinoma by penetration of the muscularis mucosae and a complex epithelial growth pattern. These lesions differ clinically from exophytic hyperplastic polyps by being more frequent on the right side than in the left colon and being relatively more common in women.