How far back in my family should I go for breast cancer history?

People test at all ages, but we only test adults (ages 18 and older) for BRCA1/2 because these genes do not cause childhood cancers. Women in their 20s would benefit from knowing whether they need high-risk screening (mammogram plus MRI plus physician exam every 6 months). Family planning may also be a consideration. Women in their 30s would benefit from understanding their ovarian and breast cancer risks. Women age 40 onward also face high risks of breast and ovarian cancer if they are BRCA1/2 carriers. Women of all ages may want to sort out their genetic risks to help their close relatives understand and face their own risks.

It is best to obtain a three generation family history from both sides of your family. This should include your children, parents, siblings, grandparents, aunts, uncles, first cousins, nieces, and nephews. Include conditions each relative has/had and age of first diagnosis. For relatives who are deceased, include the cause of death and the age at death.