BRCA1 and BRCA2 gene testing
​
What is the BRCA Gene Mutation?
​
​
​
​
​
BRCA1 and BRCA2 are genes that suppress malignant tumors (cancer) in humans. When these genes change (become mutated) they do not suppress tumors as they should. So people with BRCA1 and BRCA2 gene mutations are at a higher risk of getting cancer.
​
Women with this mutation are at higher risk of getting breast cancer or ovarian cancer. Mutations may also increase a woman's risk of developing:
​
-
Cervical cancer
-
Colon cancer
-
Pancreatic cancer
-
Gallbladder cancer or bile duct cancer
-
Stomach cancer
-
Melanoma
​
What Are The Risks If You Have BRCA Mutations?
​
​
​
​
​
​
​
​
​
Who Should Think About Being Tested? Those Patients With:
​
-
Breast cancer diagnosed before age 50
-
Bilateral breast cancer
-
Breast & ovarian cancer
-
Family member with male breast cancer
-
Breast cancer and Ashkenazi (Eastern European) Jewish ancestry
-
Breast cancer before 50 in two or more blood relatives
-
A relative with a known BRCA1 or BRCA2 mutation
How is the Test Done?
​
If you decide to be tested, your blood sample is sent to a lab that specializes in genetic testing. That lab will test your blood for the BRCA1 and BRCA2 mutations. It can take weeks or months to get the test results.
What Does a Positive Test Result Mean?
A positive test result means you have inherited the BRCA1 or BRCA2 mutation.
​
-
This does not mean you have cancer, or even that you will get cancer. This means you are at a higher risk of getting cancer.
-
This also means you can or could have passed this mutation on to your children. Each time you have a child there is a 1 in 2 chance your child will get the mutation you have.
What Can Be Done If You Are BRCA Mutation Positive?
​
Screening
-
Breast:
-
Age 25-29:
-
clinical breast exam every 6-12 months
-
Breast MRI every year​
-
-
Age 30+:
-
Annual breast mammography and MRI, generally alternating every 6 months
-
Breast exams every 6 months
-
-
-
Ovarian:
-
Pelvic sonogram and CA-125 until risk-reducing removal of ovaries and tubes
-
Every six months beginning at age 30
-
​
Medicine
-
Breast:
-
Tamoxifen
- Can be considered in patients age 35 or older and not planning on pregnancy, or on mastectomy.
-
Reduces breast cancer risk by 62% in BRCA2 carriers, but has not been found to reduce risk of cancer in BRCA1 carriers.
-
Generally preferred in pre-menopausal patients, except for those with increased risk factors for endometrial hyperplasia. Risk of endometrial hyperplasia.​​
-
​Raloxifene
-
Reduces invasive breast cancer in postmenopausal women.​
-
Side effects: hot flashes, vaginal symptoms (dryness, itching, dyspareunia), and increased risk of blood clots.
-
Another significant side effect is leg cramps!
-
Does not act on endometrium.
-
-
-
Ovary:
-
Birth control pills reduce ovarian cancer risk 33-80% for BRCA1, 58-63% for BRCA2.
-
No increased risk of breast cancer in those with BRCA mutations using birth control pills.
-
​
Surgical
-
Breast: bilateral mastectomy
-
Offered to any patient with BRCA mutation; reduces risk by 85-100%
-
​
-
Ovarian: bilateral salpingo-oophorectomy
-
The most effective option for risk reduction
-
Should be considered by age 35-40 for BRCA1 patients, 40-45 for BRCA2 patients
-
This can be individualized based on the patient’s family history and plans for childbearing
-
Fertility-preservation with oocyte or embryo cryopreservation
-
-
What Does a Negative Test Result Mean?
If your test result for the BRCA1 and BRCA2 mutations is negative. But a negative test result does not mean you will not get cancer. It may mean you have the same risk of getting cancer as people who do not have this mutation.