Colorectal Polyps and Polyposis

Abstract

Colorectal polyp is a common lesion in colorectum. It can be either benign or malignant. Colorectal polyp may be classified into epithelial and nonepithelial polyp according to its origin. The most common epithelial polyp is adenomatous polyp followed by serrated polyp, hamartomatous polyp, and inflammatory polyp. Epithelial polyps are either polypoid or nonpolypoid. Endoscopic features such as surface pit pattern and narrow band image pattern may help differentiation of histopathology of epithelial polyps. There are a variety of nonepithelial polyps, which include neuroendocrine tumor, lipoma, leiomyoma, GIST, and lymphangioma. Endoscopic characteristics such as size, color, consistency, and location may help the differential diagnosis of nonepithelial polyps in colorectum. In some patients, numerous polyps are present in colorectum and/or in other parts of gastrointestinal tract, which is called polyposis. Polyposis syndrome is classified into hereditary and nonhereditary polyposis.