BREAST CANCER (BRCA) GENE TEST
A breast cancer (BRCA) gene test is a blood test to check for specific changes in genes that help control normal cell growth. Finding changes in these genes, called BRCA1 and BRCA2, can help determine your chance of developing breast cancer and ovarian cancer. A BRCA gene test does not test for cancer itself. This test is only done for people with a strong family history of breast cancer or ovarian cancer, and sometimes for those who already have one of these diseases. Genetic counseling before and after a BRCA test is very important to help you understand the benefits, risks and possible outcomes of these test.
A woman's risk of breast cancer and ovarian cancer is higher if she has BRCA1 or BRCA2 gene changes. Breast cancer is extremely rare in men but BRCA2 gene changes have been linked to male breast cancer and possibly prostate cancer. The risk of some other types of cancers, including pancreatic and colon cancer may also be higher. The gene changes can be inherited from either your mothers or fathers side of the family.
What are BRCA1 and BRCA2?
BRCA1 and BRCA2 are human genes that belong to a class of genes know as tumor suppressors.
In normal cells, BRCA1 and BRCA2 help ensure the stability of cell's genetic material (DNA) and help prevent uncontrolled cell growth. Mutation of these genes has been linked to the development of hereditary breast and ovarian cancer.
The names BRCA1 and BRCA2 stand for breast cancer susceptibility gene 1 and breast cancer susceptibility gene 2, respectively.
How do BRCA1 and BRCA2 gene mutations affect a person's risk of cancer?
Not all gene changes, or mutations are harmful. Some mutations may be beneficial, whereas others may have no obvious effect. Harmful mutations can increase a person's risk of developing a disease, like cancer.
A woman's lifetime risk of developing breast and or ovarian cancer is greatly increased if she inherits a harmful mutation in BRCA1 or BRCA2.
Such woman has an increased risk of developing breast or ovarian cancer at a early age and often has multiple, close family members who have been diagnosed with these diseases. Harmful BRCA1 mutation may also increase a woman's risk of developing cervical, uterine, pancreatic, and colon cancer. Harmful BRCA2 mutations may additionally increase the risk of pancreatic cancer, stomach cancer, gallbladder and bile duct cancer, and melanoma .
Men with harmful BRCA1 mutations also have an increased risk of breast cancer and possibly, of pancreatic cancer, testicular cancer, and early-onset prostate cancer. However, male breast cancer, pancreatic cancer, and prostate cancer appear to be more strongly associated with BRCA2 gene mutations.
The likelihood that a breast and or ovarian cancer is associated with a harmful mutation is BRCA1 or BRCA2 is highest in families with a history of multiple cases of breast cancer, cases of both breast cancer and ovarian cancer, one or more family members with two primary cancer or an Ashkenazi (Eastern European) Jewish background. Other ethnic and geographic populations around the world, such as the Norwegian, Dutch and Icelandic people have a higher frequencies of specific BRCA1 and BRCA2 mutations.
Genetic tests are available, to detect BRCA1 and BRCA2 mutations, and how they are performed.
Several methods are available to test for BRCA1 and BRCA2 mutations. Most of these methods look for changes in BRCA1 and BRCA2 DNA. At least on method looks for changes in the proteins produced by these genes. A combination of methods are use.
A blood sample is needed for these test. The blood is drawn in a laboratory, doctor's office, hospital, or clinic and then sent to a laboratory that specializes in the test. It usually takes several weeks or longer to get the results. A person who decides to get tested should check with their health care provider to find out when the results maybe available.
Genetic counseling is recommended before and after a genetic test. The counseling should be done by a health care professional who is experienced in cancer genetics. Genetic counseling usually involves a risk assessment based on the person's personal and family medical history and discussions about the appropriateness of genetic testing, the specific test that might be used and the technical accuracy of the tests, the medical implications of a positive a negative result, the possibility that a test result might not be informative, the psychological risks of benefits of genetic test results, and the risk of passing a mutation to children.
How do people know if they should consider genetic testing for BRCA1 and BRCA2 mutation?
Currently there are no standard criteria for recommending or referring someone for these test.
In a family with a history of breast cancer and or ovarian cancer, it may be most advised to test a family member who has breast cancer or ovarian cancer. If that person is found to have a harmful BRCA1 or BRCA2 mutation, then other family members can be tested to see if they to may have the mutation.
Regardless, women who have a relative with a harmful BRCA1 or BRCA mutation and women who may be at high risk of breast cancer or ovarian cancer because of family history should consider genetic counseling to learn more about their potential risks and about BRCA1 and BRCA2 genetic tests
The risk of a harmful mutation in BRCA1 and BRCA2 are increased with certain familial patterns of cancer, such as:
For women who are not of Ashkenazi Jewish descent:
- two first-degree relatives (a mother, daughter, or sister) diagnosed with breast cancer, one of whom was diagnosed at age 50 or younger:
- three or more first-degree or second-degree (grandmother or aunt)relatives diagnosed with breast cancer regardless of their age at diagnosis:
- a combination of first-and second-degree relatives diagnosed with breast cancer and ovarian cancer (one cancer type per person):
- a first-degree relative with cancer diagnosed in both breast (bilateral breast cancer):
- a combination of two or more first-or second-degree relatives diagnosed with ovarian cancer regardless of age at diagnosis:
- a first-or second-degree relative diagnosed with both breast and ovarian cancer regardless of age at diagnosis:
- breast caner diagnosed in a male relative.
For women of Ashlenazi Jewish descent:
- any first-degree relative diagnosed with breast or ovarian cancer:
- two second-degree relatives on the same side of the family diagnosed with breast cancer or ovarian cancer.
How much do BRCA1 and BRCA2 mutation testing cost?
The cost for BRCA1 and BRCA2 mutation testing usually ranges from several hundreds to several thousand dollars. Insurance policies vary with regard to whether or not the cost of testing is covered. Those who are considering BRCA1 and BRCA2 mutation testing should find out about their insurance company's policies regarding genetic tests.
The information you find on our site is for education only it does not take the place of you seeking medical help from a license professional if you have any signs of breast cancer or any other medical issues.