NCI Definition: 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. [1]

Rectal adenocarcinomas most frequently harbor alterations in APC, TP53, KRAS, SMAD4, and FBXW7 [2].

Most Commonly Altered Genes in Rectal Adenocarcinoma

APC Mutation, TP53 Mutation, TP53 c.217-c.1178 Missense, TP53 Missense, and KRAS Mutation are the most common alterations in rectal adenocarcinoma [2].

Top Alterations in Rectal Adenocarcinoma

Significant Genes in Rectal Adenocarcinoma

MLH1 +

MLH3 +

MSH2 +

MSH3 +

MSH6 +


PMS1 +

PMS2 +

Disease Details

Adenocarcinoma of the Rectum, Adenocarcinoma - rectum, Rectum adenocarcinoma (CRC), Adenocarcinoma of Rectum
Rectal Carcinoma
Rectal Signet Ring Cell Adenocarcinoma and Rectal Mucinous Adenocarcinoma
OncoTree Name
Rectal Adenocarcinoma
OncoTree Code


1. National Cancer Institute. NCI Thesaurus Version 18.11d. https://ncit.nci.nih.gov/ncitbrowser/ [2018-08-28]. [2018-09-21].

2. The AACR Project GENIE Consortium. AACR Project GENIE: powering precision medicine through an international consortium. Cancer Discovery. 2017;7(8):818-831. Dataset Version 6. This dataset does not represent the totality of the genetic landscape; see paper for more information.

3. All assertions and clinical trial landscape data are curated from primary sources. You can read more about the curation process here.