Source:http://linkedlifedata.com/resource/umls/id/C0007113
NCI: Cancer that forms in the tissues of the rectum (the last several inches of the large intestine closest to the anus).,NCI: A malignant epithelial neoplasm that arises from the rectum and invades through the muscularis mucosa into the submucosa. The vast majority are adenocarcinomas.