Royal Belgian Society

Genetic testing and prophylactic mastectomy

Genetic mutations known as BRCA1 and BRCA2 harbour an increased risk for developing breast and ovarian cancer. For people that carry BRCA gene mutation, the increased lifetime risk for developing breast cancer may be as high as 85%. A simple blood test is used to determine whether or not a patient is a carrier.

Risk factors:

  • having another family member that has tested positive for a BRCA gene mutation
  • having had early onset breast cancer (diagnosed before age 45)
  • a family history of early onset breast cancer
  • a family history of ovarian cancer.

Should a patient carry one of the BRCA gene mutations, bilateral (both sides) prophylactic (preventative) mastectomies may be recommended. Patients who do not have a cancer diagnosis but are carriers can achieve a greater than 90% reduction in breast cancer risk by having prophylactic mastectomies. Patients choosing not to have preventative surgery may be screened through MRI, ultrasound, and mammography every three to six months.