Treatment of Nonmetastatic Breast Cancer

The treatment of breast cancer has evolved largely based on refinements in understanding of the biology of the disease and the variable risk for mortality among separate disease subtypes.1 Further, due to widespread use of screening mammography, there is a reduction in average breast tumor size at diagnosis. Breast cancer primarily affects women but also affects a smaller number of men. Because many clinicians provide medical care to patients with breast cancer, familiarity with contemporary treatments is important. In this JAMA Insights article, current practices and emerging trends in breast oncology are highlighted, including aspects of precision oncology and the recent deescalation of certain treatments to minimize long-term toxicities.