Hereditary Colorectal Cancer Syndromes

Colon cancer affects close to 150,000 individuals in the United States each year; 5 - 10% of this cancer burden is due to a hereditary type of colorectal cancer. The most common types are:

Cancer/Syndrome

Gene(s)

Lynch Syndrome or (HNPCC)

MLH1, MSH2, MSH6, PMS2, EPCAM

Muir-Torre Syndrome (variant of Lynch Syndrome with sebaceous skin findings)

MSH2, some MLH1

Familial Adenomatous Polyposis (FAP)

APC

Gardner's Syndrome (variant of FAP)

APC

Attenuated FAP (AFAP)

APC

MYH-Associated Polyposis (MAP)

MYH

We are able to test for several genes known to be associated with each of the hereditary colorectal syndromes. The presence of a mutation in one of these genes could increase one's risk of colorectal cancer, and other associated cancers: endometrial (uterine), ovarian, gastric, ureter/renal pelvis, biliary tract, small bowel, pancreatic, brain, and sebaceous adenomas.

Individuals who should be offered genetic risk assessment are those with a personal or family history of:

  • Colorectal cancer diagnosed before age 60
  • Endometrial cancer diagnosed before age 50
  • Two or more Lynch-related cancers (see above) in an individual or family
  • An individual with abnormal tumor screening (microsatellite instability or immunohistochemistry)
  • Individuals with 10 or more cumulative colorectal adenomatous polyps
  • Relatives of a Lynch, APC or MYH mutation carrier, or another type of hereditary colon cancer gene mutation