There are many reasons why people decide to have genetic testing.  Typically, it is because they have a personal and family history of cancer and want to know if they are at risk of developing hereditary cancer.  Some people feel that knowing their risk allows them and their family members to make informed decisions about health management. 

Genetic testing for hereditary breast and ovarian cancer is done through a complex lab test on a blood sample.  The time it takes to get results can vary greatly from several months to a year.  The test does not detect cancer, but rather looks for inherited changes (called mutations) in two genes that everyone is born with - BRCA1 and BRCA2.  Scientists have identified specific mutations in these genes that significantly increase the risk of developing breast, ovarian and prostate cancer.  The BRCA1 and BRCA2 mutations are more common in certain ethnic groups such as families of Ashkenazi (European) Jewish descent.  Not everyone with a mutation in these genes will develop cancer, it simply means that the risk is much higher than average.

 

The first steps

To get an appointment, ask your family doctor for a referral or call a clinic yourself. Genetic counselling clinics are usually located in hospitals and cancer centres and offer counselling and testing by certified health care professionals. Contact the Canadian Association of Genetic Counsellors for a full list of clinics.

In Canada, genetic counselling prior to genetic testing is mandatory for it to be covered by provincial health insurance.  Genetic counsellors will assess your personal and family medical history to determine if you meet the eligibility requirements for provincially-funded genetic testing (the criteria vary somewhat from province to province).  They will also provide information to help you make a decision about whether or not to have genetic testing.

If your family history does not suggest that you’re at risk of developing hereditary breast cancer, you may not qualify for a genetic testing, but you may still be at a moderately increased risk of developing certain types of cancer and the genetic counsellor can provide information about risk management including enhanced screening and surgery, regardless of whether you choose to have testing or not.

What should be considered before getting tested?

The decision about whether or not to have genetic testing is a personal one.  There are some advantages and disadvantages of genetic testing:

Advantages

▣ Results can clarify your cancer risk and help you make informed health decisions
▣ Provides important medical information to family members
▣ Negative results may reduce anxiety

Disadvantages

▣ Results may not clarify your cancer risk
▣ Family members may react negatively
▣ Possible genetic discrimination

Genetic discrimination means being treated unfairly based on information about your genetic make-up.  There are currently no laws that specifically protect Canadians against this kind of discrimination.  This means that it is possible that insurance companies may deny you coverage if they feel you are at a high risk of developing cancer. It is important to be informed about the ramifications before getting tested. 

To learn more about the steps you can take to reduce your risk of developing breast cancer, who is at risk and what to do if you are concerned about your risk download the informational booklet Breast Cancer in the Family: Understanding Your Risk at Willow Breast & Hereditary Cancer Support’s website.