ERBB2 and cancer: The recently presented results of the DESTINY-Breast06 trial showed that the relative and absolute benefit from trastuzumab deruxtecan is the same between metastatic HER2-low and “ultra-low” cancer [34], which expands the candidate population and further underscores the importance of our findings and conclusions, especially concerning the proportion of “ultra-low” assessments among our rescored HER2 0 biopsies.