Testable Inherited Cancer Syndromes
About 5 percent to 10 percent of all cancer cases occur in someone who inherited a genetic mutation that increases cancer risk. The mutations and syndromes that are discussed in cancer care are:
BRCA1 and BRCA2 Genetic Mutations
A woman who inherits a BRCA (BReast CAncer) genetic mutation has an increased risk of developing breast and ovarian cancer. A man who inherits a BRCA mutation has an increased risk of developing breast and prostate cancer.
This syndrome is the result of mutations in the PTEN gene. A woman with this syndrome is at increased risk of developing breast and uterine cancer. The mutations also put women and men at increased risk of thyroid cancer.
Familial Adenomatous Polyposis
This syndrome is caused by mutations in the APC gene. These mutations increase the risk of colorectal cancer. They also can increase the risk of soft tissue tumors and brain tumors.
Most people with Li-Fraumeni syndrome, a rare genetic condition, have mutations in the TP53 gene, increasing the risk of many different types of cancer. The most common are soft tissue sarcomas (tumors in fat, muscles, nerves, joints, blood vessels, bones or deep skin), breast cancer, leukemia, lung cancer, brain tumors and adrenal gland cancer.
Also referred to as hereditary nonpolyposis colorectal cancer (HNPCC), this syndrome increases colorectal cancer risk due to mutations in DNA mismatch repair genes called MLH1, MSH2, MSH6 or PMS2. Variations of these mutations can also cause Muir Torre syndrome or Turcot syndrome, increasing the risk for certain skin cancers or brain tumors, respectively.
Multiple Endocrine Neoplasia (MEN)
There are two types of MEN syndrome: MEN1 is caused by a mutation in the MEN1 gene. MEN2A and MEN2B are caused by mutations in the RET gene. All three mutations increase the risk of cancers of the endocrine system.
Von Hippel-Lindau Disease
This disorder, which is the result of mutations in the VHL gene, causes an abnormal growth of blood vessels (called hemangioblastomas or angiomas), and increases the risk of kidney and other cancers.