A cruel fact of life is that all family histories aren’t created equal. This large Swedish cohort study indicates having a first degree female relative with breast cancer was associated with a lower risk of breast cancer death (HR 0.78), particularly among ER-negative breast cancers (HR 0.57). The thought is that these women are more aware of breast cancer and seek treatment early. An interesting caveat was that those with a first degree female relative diagnosed before age 40 actually had a higher risk of breast cancer death (HR 1.41) suggesting a family history of early breast cancer in particular may be a unique harbinger of predisposition for bad biology breast cancer. | Zhang, JAMA Netw Open 2023
