Genetic testing is the sequencing of human DNA in order to discover genetic differences, anomalies, or mutations that may prove pathological.
Who should consider genetic testing?
If you have a strong family history of breast cancer, genetic testing can help you determine if you are at risk. Some of the more common characteristics of families with a genetic predisposition to developing cancer include:
- Cancer diagnosed at an early age
- Multiple blood relatives with cancer
- More than one type of cancer in the same individual or a rare cancer (e.g. male breast cancer)
- Family member who has been diagnosed with a hereditary type of cancer
- Ashkenazi Jewish ancestry and one of the above risk factors
What can genetic testing tell you?
- Genetic testing can tell you if you carry the BRCA1 and BRCA2 mutations, along with other cancer-causing genes.
- Genetics counselors determine your risk of developing cancer by specifically mapping your personal and family medical history, as well as other medical testing.
- Once it is determined that you may be at risk, genetics counselors will work with you to determine the best and most effective ways to reduce your risk of developing breast cancer.
If you find out you have an abnormal gene linked to breast cancer, there are proactive measures you can take to help keep your risk as low as possible:
- Lifestyle. Maintain a healthy weight, exercise regularly, limit alcohol, eat a balanced diet and stop smoking.
- Hormonal therapy medicines. Your doctor may recommend SERMs (selective estrogen receptor modulators), which have been shown to reduce the risk of developing hormone-receptor-positive breast cancer in women at high risk. Tamoxifen and Evista (chemical name: raloxifene) are the two SERMs used in this way.
- More frequent screening. If you’re at high risk because of an abnormal breast cancer gene, you and your doctor should develop a screening plan tailored to your unique situation.
For women at a high-risk for developing breast cancer, additional screening steps may include:
- A monthly breast self-exam
- A yearly breast exam by your doctor
- A digital mammogram every year starting at age 30 or younger
- An MRI scan of your breast every year
- A breast ultrasound
- Protective (prophylactic) surgery to remove healthy breasts and ovaries