COLARIS AP® is the most accurate, highest quality genetic test available to diagnose adenomatous polyposis syndromes (FAP, AFAP, and MAP). For patients who test positive for an APC gene mutation, there is up to a 100 percent lifetime risk of developing colorectal cancer. This is greatly increased when compared to the general population risk of only six percent.^{26, 35, 36} For patients who have biallelic MYH mutations, the exact risk of colorectal cancer is unknown. However, due to the relationship of MAP to multiple colorectal adenomatous polyps, the colorectal cancer risk is thought to be significantly elevated in these patients.^{57, 59}

APC mutation carriers are also at greater risk of developing extracolonic cancers, including: duodenal/periampullary, thyroid, pancreatic, central nervous system, gastric, bile duct, and adrenal gland. Children with FAP are at risk for hepatoblastoma.⁵² There is also a higher incidence of extracolonic manifestations such as desmoid tumors, osteomas, dental abnormalities, and congenital hypertrophy of the retinal pigment epithelium (CHRPE) for mutation carriers.⁶⁰ It is currently unknown whether patients with MAP are at an increased risk of extracolonic cancers, although CHRPE and duodenal polyps have been reported in these individuals.⁶¹

Cancers Associated with FAP and AFAP

* Cancer risks for MAP are currently unknown, although the association with multiple adenomas is thought to increase the risk of colorectal cancer significantly.

» Managing Patients with Adenomatous Polyposis Syndromes

A genetic test for adenomatous polyposis syndromes