NCI Definition: A malignant neoplasm arising from the glandular epithelium of the appendix with invasion of the appendiceal wall beyond the muscularis mucosa. The majority of cases are well differentiated adenocarcinomas with mucinous stroma formation. Clinically, it may present as an abdominal mass or with symptoms of acute appendicitis. Patients with chronic ulcerative colitis are at a higher risk in developing appendiceal adenocarcinomas compared to the general population. [1]

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

Most Commonly Altered Genes in Appendix Adenocarcinoma

KRAS Mutation, KRAS Exon 2 Mutation, KRAS Codon 12 Missense, GNAS Mutation, and KRAS G12D are the most common alterations in appendix adenocarcinoma [2].

Top Alterations in Appendix Adenocarcinoma

Disease Details

Adenocarcinoma of Appendix, Appendiceal Adenocarcinoma, Adenocarcinoma of the Appendix
Appendix Carcinoma
Colonic Type Adenocarcinoma of the Appendix, Appendix Signet Ring Cell Carcinoma, and Appendix Mucinous Adenocarcinoma
OncoTree Name
Appendiceal 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 8. 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.