Hereditary Cancer and Genetic Testing

syndromes

This section covers the following topics:


What is a cancer syndrome?

In medicine, a syndrome refers to a collection of symptoms or signs with a common cause. Sometimes doctors refer to certain inherited mutations as causing a syndrome. Not all inherited gene mutations are associated with a syndrome, and some are associated with more than one syndrome or referred to by more than one name. This can be confusing for people who are trying to understand the medical risks associated with their mutation. The table below lists different syndromes and the genes associated with them. If you have been told you have a syndrome, it's very important for you to learn your exact mutation. Make sure that you receive a copy of your genetic test results and discuss your results with a genetics expert. If you are uncertain or do not have a copy of your genetic test results, you may request a copy from your health care provider. Some testing labs may make the results available to you directly through a patient portal. 

The two most common syndromes are hereditary breast and ovarian cancer syndrome () and


Hereditary breast and ovarian cancer syndrome ()

is a name given to inherited mutations in one of two genes:

Breast and ovarian cancer are the two most common cancers in people with and . However, "" can be misleading because mutations in these two genes can also increase the risk for pancreatic,  and other cancers. Because it involves breast and ovarian cancer, “” may imply that these genes don't affect men. However, half of people with a or mutation are male. 

There are guidelines that outline what is known about the cancer risks associated with and options for screening, prevention and treatment of cancers in people with inherited mutations in these genes. In the past, the guidelines were the same for both genes. As research on these genes has continued, experts have found that the cancer risks for each gene are somewhat different from one another. For this reason, experts have started to separate out the different risks and medical options for and . Despite these differences, some references still use the term  when referring to inherited mutations in either gene. 

If you have been told that you have , it is important to know whether the mutation you inherited is in a or gene, so that you can make informed decisions about your medical care. 


is caused by an inherited mutation in one of these five genes:

People with have an increased risk for colorectal, endometrial and other cancers. The cancer risk varies by gene mutation, therefore it is important for people with to know which gene mutation they have.

In the past, the risk-management guidelines were the same for people with an inherited mutation in any of the  genes. As more research has shown different cancer risks for each gene, experts have started to separate the risks and medical options for each individual mutation. Despite these differences, some references discuss  as though inherited mutations in these genes carry the same risks. 

If you have been told that you have or , it is important to know which gene has a mutation, so that you can make informed decisions about your medical care. 

In the past, was also referred to as “hereditary nonpolyposis colorectal cancer” (). This term has fallen out of favor because mutations in these genes also increase the risk for other cancers besides colorectal cancer. 


Cancer syndromes and associated genes

This chart lists the genes that are associated with some of the most common syndromes. 

Syndrome Genes
Hereditary Breast and Ovarian Cancer ()

Lynch; also called "Hereditary Nonpolyposis Colorectal Cancer" ()  

Li-Fraumeni 

  

Hereditary Diffuse Gastric Cancer 

Peutz-Jegher 

Familial Atypical Mole/ Multiple Melanoma (FAMMM) + Pancreatic Cancer

CDKN2A (p16INK4a)

Hamartoma Tumor syndrome (PHTS); also known as Cowden's syndrome

Familial Adenomatous Polyposis; also associated with Gardner and Turcot syndromes

APC (people with the common APC variant I1307K have increased risk for colorectal cancer, but do not develop FAP)

MUTYH Associated Polyposis (MAP) MUTYH (people with mutations in both copies of their MUTYH gene develop MAP, people with a mutation in one copy of their MUTYH gene have an increased risk for colorectal cancer, but do not develop MAP)
Last updated March 19, 2022