Decision box

This blood test detects mutations of the BRCA1 and BRCA2 genes. Individuals who carry these mutations have a higher risk of developing breast and ovarian cancer.

1. Risk avoidance: increased physical activity and control of obesity, limiting alcohol consumption and dietary fat 
2. Cancer screening or surveillance 
3. Chemoprevention (e. g. tamoxifen, raloxifene) 
4. Risk-reducing surgery (mastectomy, salpingo-oophorectomy)

1. Individuals who have a family history of: 
   • known BRCA1/2 mutation 
   • ovarian cancer in 2 or more relatives, at any age 
   • ovarian cancer at any age AND breast cancer under the age of 60 in 3 or more relatives 
   • breast cancer in 3 or more relatives average age of onset before age 50
   • male breast cancer AND ovarian cancer1 
2. Individuals of French-Canadian or Eastern European ancestry who are diagnosed with breast cancer under the age of 50, are diagnosed with ovarian cancer at any age, or have a first-degree relative who was diagnosed with breast or ovarian cancer under the age of 50. 
3. Individuals of Ashkenazi Jewish heritage diagnosed with breast cancer under the age of 65 or ovarian cancer at any age or with a first-degree relative affected by breast or ovarian cancer under the age of 65.
   • Individual risk for a BRCA1 or BRCA2 mutation can be calculated at https://webapps.myriad.com/brca-risk-calculator/calc-embed.html

There are pros and cons to taking this test 

• PROS: Individuals might benefit from knowing that they carry a mutation by taking steps to reduce their cancer risk. 
• CONS: At least 12% of individuals who test negative for the mutation may still develop breast cancer and 1% may still develop ovarian cancer. From 35 to 90% of individuals with a BRCA1/2 gene mutation (depending on the mutation and of type of cancer) will not have breast or ovarian cancer, so screening could lead to an unnecessary invasive intervention that could have serious side effects.