The use of current standard HER2 assays as diagnostic tests may result in misassignment of patients for treatment of breast cancer with trastuzumab deruxtecan, according to a study published in JAMA Oncology.
«To accurately determine which patients will benefit from trastuzumab deruxtecan, clinicians should insist that their pathology partners use a new, more sensitive assay. The legacy protein assay and the fluorescent in situ hybridization (FISH) assays are not appropriate for trastuzumab deruxtecan and similar drugs in the pipeline,» study co-author David L. Rimm, MD, PhD, Anthony N. Brady