Metastatic Breast Cancer Treatment Guidelines and the Nuances of HER2-Low Disease in Clinical Practice

Panelists discuss how the National Comprehensive Cancer Network (NCCN) and American Society of Clinical Oncology (ASCO)/College of American Pathologists (CAP) guidelines for HER2-negative breast cancer (BC) have evolved to recognize HER2-low (IHC 1+  or 2+/ISH-negative) and HER2-ultra low (IHC 0) as distinct categories. These classifications, particularly HER2-low, guide eligibility for targeted therapies such as trastuzumab deruxtecan, expanding treatment options beyond traditional chemotherapy for previously categorized HER2-negative patients.