Breast Cancer Genetic Testing

In the past few years, two genes have been discovered that place women at extremely high risk for developing breast and ovarian cancer and, to a much lesser degree, colon cancer. These genes are the BRCA1 and BRCA2 genes. (BR=breast, CA=cancer) The gene discoveries in 1994 and 1996 received much attention in the press as "the" test for breast cancer. However, in reality, it only shows that there is an altered (mutated = changed) cell that indicates the carrier is at very high risk for cancer development. The test is only appropriate for a small number of women and men and not the general public. It is estimated that only about 7 - 10% of breast cancers are caused by these mutated genes.

Women who inherit the BRCA1 gene have a 56 - 80% risk of having breast cancer by the age of 70 and also have a 40 - 60% chance of developing ovarian cancer. Men who have the gene have an increased risk for prostate cancer. There is also an increased risk for both men and women of developing colon cancer.

People who inherit the BRCA2 gene also have the same risk for developing breast cancer as in BRCA1 but have a reduced risk of between 15 - 20% of ovarian cancer. The BRCA2 gene increases the risk for men to have breast cancer as well as prostate cancer.

These altered genes are inherited from a mother or father. They can then be passed on to your children (male or female) if you are a carrier, placing them at higher risk for breast, ovarian/prostate or colon cancer. Your children are at 50% risk of inheriting the altered gene if you are a carrier.

People can now have a blood test to determine if they are a BRCA1 or BRCA2 gene carrier increasing their risk for these cancers. To determine if you are a candidate for genetic testing, you will need a risk assessment from a professional medical team trained to evaluate your family history to see if you meet the strict criteria for testing. If your history determines you are a candidate, counselors will discuss with you the advantages, disadvantages and limitations of testing. You will be given an opportunity to decide if you wish to further pursue testing.

Testing consists simply of having several tablespoons (30 ccs, approximately 5 - 6 teaspoons) of blood drawn from your arm and sent to a laboratory for testing.

Benefits of Testing :

• Allows you to know if you carry one of these altered genes, putting you at very high risk for developing breast, ovarian/prostate and, to a lesser degree, colon cancer. You would then be given options for surveillance to ensure that you have the best chance against developing the disease. It would also allow you to plan your childbearing if you are a young woman.
  
• A negative test would relieve your anxiety about being a carrier and prevent unnecessary, expensive surveillance tests. You would be placed back at the normal risk for developing breast cancer.
  
• Allows family members to choose to be tested or placed in high-risk surveillance programs for early detection. Early detection allows breast cancer to be found when it is most successfully treated.
  
• Assists your physicians in planning treatment protocols to prevent and/or detect other.cancers.

Potential Disadvantages of Positive Test Results:

• May face discrimination from insurance providers to keep or obtain health or life insurance
  
• May have emotional or psychological problems knowing you are at high risk for cancer
  
• Family members may react unpredictably to positive test results (a positive test places you and possibly them at higher risk for cancer because same blood line)
  
• Possibility that positive carrier could be denied child custody or adoption privileges

The criteria for being tested for the BRCA1 or BRCA2 gene is based on the degree of risk your family or personal history presents.

Testing is now performed for:

• Person with breast and/or ovarian cancer who has two or more first* or second-degree* blood relatives (on one side of family, maternal or paternal) with either breast or ovarian cancer.
  
• Person with personal diagnosis of breast and/or ovarian cancer who has one first or second-degree* blood relative younger than 45 (some authorities say 50 years of age or pre-menopausal) with breast cancer and/or ovarian cancer at any age.
  
• Personal history of breast/ovarian cancer developed before age 45 (some authorities say 50 years of age or pre-menopausal)
  
• Personal history of breast/ovarian cancer that is bilateral (both sides) or has multiple primary sites of cancer
  
• Males who develop breast cancer
  
• Blood relative (first- or second-degree relative*) of BRCA1 or BRCA2 documented gene carrier

• First-Degree: mother, father, sister, brother, daughter, son
  
• Second-Degree: aunt, uncle, grandmother, grandfather, granddaughter, grandson, niece, nephew, half-brother, half-sister

Genetic Testing Exclusions:

• Person under 18 years of age
  
• Cognitively impaired person, unable to give informed consent
  
• Psychologically impaired according to professional evaluation

Decision to Test or Not Test

The decision to have genetic testing should be made in partnership between you and a professional treatment team who:

• evaluates your risks
  
• determines whether you meet criteria for testing
  
• offers you professional psychological counseling before and after the test results
  
• answers all of your questions about the process
  
• provides written information on the test and lab performing test
  
• obtains informed consent for testing
  
• protects your confidentiality
  
• develops a surveillance/treatment plan after testing

For more information, please call The Connie Dwyer Breast Center at (973) 877-5189.

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