MedGen

MUTYH polyposis (also referred to as MUTYH-associated polyposis, or MAP) is characterized by a greatly increased lifetime risk of colorectal cancer (CRC). Although typically associated with ten to a few hundred colonic adenomatous polyps, CRC develops in some individuals in the absence of polyposis. Serrated adenomas, hyperplastic/sessile serrated polyps, and mixed (hyperplastic and adenomatous) polyps can also occur. Duodenal adenomas are common, with an increased risk of duodenal cancer. The risk for malignancies of the ovary and bladder is also increased, and there is some evidence of an increased risk for breast and endometrial cancer. Additional reported features include thyroid nodules, benign adrenal lesions, jawbone cysts, and congenital hypertrophy of the retinal pigment epithelium. [from GeneReviews]

An adenocarcinoma arising from the rectum. It is more frequently seen in populations with a Western type diet and in patients with a history of chronic inflammatory bowel disease. Signs and symptoms include intestinal bleeding, anemia, and change in bowel habits. According to the degree of cellular differentiation, rectal adenocarcinomas are divided into well, moderately, and poorly differentiated. Histologic variants include mucinous adenocarcinoma, signet ring cell carcinoma, medullary carcinoma, serrated adenocarcinoma, cribriform comedo-type adenocarcinoma, and micropapillary adenocarcinoma. [from NCI]