A strong family history of breast cancer is indicative of the presence of certain genes that put individuals at a high risk for developing breast cancer. Genes are the biological material you inherit from your parents. They are nature’s code for the determining the way you look, think, and act. The existence of certain genes, or mutations in certain genes, can put you at a higher risk for developing specific diseases. For example, individuals with BRCA1 and BRCA2 mutations are at a drastically higher risk for developing breast and/or ovarian cancer. More genetic factors likely to exist, and many breast cancer research centers are devoted to identifying them. The following criteria were developed by the National Cancer Institute to help women decide if genetic testing is the right choice for them:

  • For women who are not of Ashkenazi Jewish descent:
    • two first-degree relatives (mother, daughter, or sister) diagnosed with breast cancer, one of whom was diagnosed at age 50 or younger;
    • three or more first-degree or second-degree (grandmother or aunt) relatives diagnosed with breast cancer regardless of their age at diagnosis;
    • a combination of first- and second-degree relatives diagnosed with breast cancer and ovarian cancer (one cancer type per person);
    • a first degree relative with cancer diagnosed in both breasts bilateral breast cancer
    • a combination of two or more first- or second-degree relatives diagnosed with ovarian cancer regardless of age at diagnosis;
    • a first- or second-degree relative diagnosed with both breast and ovarian cancer regardless of age at diagnosis; and
    • breast cancer diagnosed in a male relative.
  • For women of Ashkenazi Jewish descent:
    • any first-degree relative diagnosed with breast or ovarian cancer; and
    • two second-degree relatives on the same side of the family diagnosed with breast or ovarian cancer.

It is important to remember that only 5-10% of all breast cancer diagnoses are linked to known genetic causes.