A breast cancer genetic testing is a blood test that utilises DNA analysis to identify mutations (that is, harmful changes) in either one of the two breast cancer susceptibility genes, that is breast cancer 1 (BRCA1) and breast cancer 2 (BRCA2). However, the BRCA gene test only helps to know the chances of getting breast cancer and/or an ovarian cancer. It does not specifically test for cancer itself.
BRCA1 and BRCA2 are the genes that help control normal cell growth. Occasionally, some people may inherit changes in one of these genes. These changes are what are known as mutations. Inheritance of a mutation in a BRCA gene, for example, “BRAH-kuh”, puts one in an increased risk of breast and ovarian cancers, as well as some other cancers, like prostate and pancreatic cancers. These changes can be inherited from either of the parent’s side of the family.
The BRCA genetic testing isn’t characteristically performed on people at average risk of breast and/or ovarian cancers. It is specifically carried out on those who are likely to have an inherited mutation either based on personal or family history of breast cancer or ovarian cancer.
The limitation of breast cancer genetic testing is results aren’t always clear. A BRCA positive result indicates there’s the presence of a BRCA gene mutation that increases the risk of cancer. A negative result may indicate either of two things; that there’s no BRCA gene mutation or that there’s a gene mutation that’s yet to be discovered. A BRCA gene test may also identify a gene variant that doctors aren’t certain about. In these circumstances, it’s not always clear what the BRCA results mean for cancer risk.
It is always recommended that those going for breast cancer genetic testing undergo genetic counselling. This helps to understand what the results might mean for your health. It also helps to decide whether breast cancer genetic testing is right for you, and can help generate a list of recommended specific set of genetic tests based on family history of breast or ovarian cancer.
How to prepare for a BRCA genetic testing?
The first step to take in the BRCA gene testing process is to meet with a genetic counsellor to determine whether it’s appropriate for you and to discuss the potential risks, limitations and benefits of undergoing genetic testing.
The genetic counsellor on his part takes detailed information of your family and medical history, assesses your risk of developing cancer, discusses the risks and benefits associated with breast cancer genetic testing, and outlines your possible options.
However, before meeting with a genetic counsellor you should get some of the following things ready –
- Enough information gathered about your family’s medical history, especially of close relatives.
- Prepare detailed documentation of your personal medical history. You should also include results of previous genetic testing, if available.
You should also prepare yourself for the emotional and social implications that comes with learning your genetic status. Be prepared to face the possibility that the test could fail to provide you with clear-cut answers regarding your cancer risk.
What a BRCA gene test result maybe like?
The results of the BRCA gene test may take a couple of weeks to get ready, and it may be positive, negative or uncertain.
Positive test result
A BRCA positive test result means there is a mutation in one of the breast cancer genes, BRCA1 or BRCA2. Therefore there’s a much higher risk of developing breast cancer or ovarian cancer when compared with people who don’t have the mutation. However, a brca positive result doesn’t mean there’s a certainty to develop cancer.
A BRCA positive test result is usually followed up with specific measures to modify the type and frequency of screening for cancer and to consider procedures and medications designed to reduce your cancer risk. What measure to be taken is, however, dependent on many factors, such as age, medical history, prior treatments, past surgeries and personal preferences.
Negative test result
A BRCA negative test result means there was no BRCA gene mutation found. However, a BRCA gene test result is considered truly negative only if it does not find a specific BRCA mutation that’s already been identified in a relative.
Unfortunately, a BRCA negative test result is not an assurance that the person won’t get breast cancer. There is still the same cancer risk as that of the general population.
Uncertain test result
There’s a third type of a BRCA gene test result known as a variant of uncertain significance. This occurs when the breast cancer genetic analysis finds a genetic variant that may or may not be associated with an increased risk of cancer. For this, it will be helpful to meet with a genetic counsellor to fully understand the outcome of this finding and decide on appropriate follow-up.
What do BRCA positive means?
A BRCA positive result indicates there’s the presence of a BRCA gene mutation (that is, harmful changes) that increases the risk of cancer.
The detection of mutations in either breast cancer gene, that is BRCA1 or BRCA2, significantly increase the risk of:
- Breast cancer
- Ovarian cancer
- Prostate cancer
- Male breast cancer
- Pancreatic cancer
What are BRCA1 and BRCA2?
BRCA1 and BRCA2 are the genes that help control normal cell growth. They belong to a class of genes known as tumour suppressors. Abnormal or harmful changes, known as a mutation, to these breast cancer genetics have shown to have a relationship with an increased risk of developing breast cancer and ovarian cancer
How much does BRCA testing cost?
The cost for BRCA gene mutation testing usually ranges from several hundreds of dollars to several thousand dollars.
How does breast cancer genetic testing works?
Testing for breast cancer genetic mutations involves only a simple draw of blood or a saliva sample, which is sent to a special laboratory for analysis. Results are usually returned several weeks after. It is recommended to go for genetic counselling before and after testing.
What are my options if I test positive?
There are several options you can explore to manage your cancer risk.
- Surveillance: that is, constant breast cancer screenings including yearly mammography, breast MRI, clinical breast examination every six months and practising breast self-awareness. The earlier this is started the better
- Surgery: removal of ovaries and fallopian tubes reduces the risk of both breast, ovarian and fallopian tube cancer. It is imperative to take the timing, family planning and the usual age at which ovarian cancer develops in those with BRCA gene mutations into consideration before the removal of the ovarian and fallopian tube
Women may also consider the removal of their breasts removed to reduce their risk of developing breast cancer.
- Medication: Three certain drugs have shown great potential to decrease the risk of breast cancer. They are tamoxifen, raloxifene and exemestane. Your doctor will recommend the best option for you.
- Risk avoidance: this involves the adoption of certain lifestyle behaviours that have been linked to reducing cancer risk. These include eating a diet that is high in fruits, limiting alcohol consumption, vegetable diet, tobacco cessation, and increasing physical activity.
Your doctor will, however, be the one to determine the most suitable option for you.
Should I be concerned about BRCA gene mutations?
You should only be concerned about breast cancer or taking the BRCA genetic testing if
- You have high numbers of family members with cancer diagnoses throughout several generations, either maternal or paternal.
- You have a family member diagnosed with cancer before the age of 45.
- You have family members that have been diagnosed with multiple cancers, such as breast and ovarian cancers.
- You have a personal history of male breast cancer.
- You have one or more relatives with a history of cancer that meet any of the criteria for breast cancer genetic testing
Those who do not have any of these family history patterns have a low probability of having a harmful BRCA gene mutation.
Associated risks with breast cancer genetic testing
There’s no known medical risk associated with being tested for a BRCA gene mutation other than the ones associated with having your blood drawn such as lightheadedness, bleeding or bruising. Other consequences surrounding breast cancer genetic testing may include the emotional, financial, medical and social implications of your test results.
However, a BRCA positive test result may come with feelings of anxiety, anger, sadness or depression and the inevitability of breast cancer.
As for BRCA negative test results or results that aren’t clear-cut, you may experience survivor guilt and uncertainty and concerns that your test result may not be a true negative result