|
|
|||||||
![]() |
|
||||||
![]() |
|
||||||
|
|
|||||||
|
|
|||||||
|
|
|
|
|
|
|
|
|
| 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 :
|
Potential Disadvantages of Positive Test Results:
Who Is A Candidate For Genetic Testing?
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:
*Definition of First- and Second-Degree Relatives
Genetic Testing Exclusions:
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:
|
|