Genetic Testing for Breast Cancer

Breast cancer is the most common type of cancer amongst women. It is one of the leading causes of deaths due to cancer worldwide. Every year, close to 200,000 women are diagnosed with breast cancer. It is a well established fact that some people are genetically predisposed to developing some form of cancer. Breast cancer and ovarian cancer also carry an inherited risk of developing amongst women. However, only 10% of breast cancer cases are a result of inheritance while others are due to other factors. Nonetheless, a knowledge of your genetic makeup indeed helps in determining if you are at an elevated risk of developing these two forms of cancer. Genetic testing for breast cancer is performed to determine this very risk. Let us now understand about genetic testing and screening for breast cancer.

What is Genetic Testing for Breast Cancer and Ovarian Cancer?

While all women carry a certain amount of risk for developing breast and ovarian cancer, women with mutation in certain genes are at an increased risk of developing cancers. Scientists have identified these genes as BRCA 1 and BRCA 2. Although, it is possible that there could be more genes responsible for developing these cancers, mutation in these two genes is definitely linked to breast and ovarian cancers. So far, two mutations in BRCA 1 and one mutation in BRCA 2 gene has been identified. Not everyone carries the mutated gene for cancer. Some populations are more susceptible to carry mutated BRCA genes. Women of Ashkenazi Jewish descent have the highest incidence of carrying this gene.

A genetic test analysis the genetic pedigree of a person. An educated guess is made regarding the incidence of cancer in the family and high risk members. An actual blood test is performed to detect the presence of BRCA 1 and BRCA 2 gene mutation. The test is not advisable to women with an average risk of cancer. However, women with known predisposition for cancer should get a genetic testing done. Given below are the conditions in which one should consider taking up this test.

    * First degree relative (parent, sibling, children) diagnosed with breast or ovarian cancer at premenopausal age.
    * Two or more members in the family with breast cancer or ovarian cancer or both.
    * Family member with a positive genetic test for breast cancer.
    * Your own history of breast cancer (most importantly bilateral breast cancer) or ovarian cancer.
    * Abnormal breast tissue biopsy in the past.

Significance of Genetic Testing

Genetic test result interpretation is done by a human genetics expert or an oncologist. A positive test result signifies that you have a mutated gene for BRCA 1 or BRCA 2. In this case, you are at increased risk of developing the two cancers. If a family member tested positive for BRCA 1 or BRCA 2 gene mutation and your test results for the same are negative, then you have an average risk of developing these cancers. However, a negative test result needs to be dealt with caution as there could be other gene that might still put you at a higher risk of developing cancer.

Those with a positive test results for genetic testing are counseled regarding various prophylactic and treatment options. Your age, the age of family members when they were diagnosed with cancer is taken into account while deciding a prophylactic course. An informed decision about lifestyle changes can be made during a session with an expert. Some women may opt for prophylactic surgeries like mastectomy (removal of healthy breast) or oophorectomy (removal of healthy ovaries). However, one must note that irrespective of a positive test result, there are 10 to 15% chances that you won't develop a cancer. Whereas, prophylactic surgeries do not completely protect you from the risk of cancer.

Genetic Testing for Breast Cancer Pros and Cons

Although, it is always better to be well informed about your genetic lineage and the risk for cancer, a decision to take a genetic test should be made carefully. Check if you and your family can cope emotionally and financially, should the test come positive. A positive test result may also strain familial relationships, whereas a negative test result may generate guilt in your mind, if another family member has a positive test result. Besides, a negative test result can unnecessarily make you relaxed in spite of carrying average amount of risk for the disease. Some women may get anxious over the credibility of the test result. Besides, the genetic testing for breast cancer cost is pretty high ranging from $200 - $2000. Also, the test results are available after weeks of wait. Although the test completely protects your privacy, there have been incidences where individuals who tested positive for this test were denied insurance coverage. More on genetic testing pros and cons.

Thus, one must consider all the pros and cons before going in for genetic testing for breast cancer. Also remember that a counseling session is as much important as the test itself.