Gustavson et al. used a deep learning approach to develop an AI-derived HER2 Quantitative Continuous Score (QCS) that predicted response to T-DXd in HER2-low cancers; the QCS high group had 53% response with a median PFS of 14.5 months, whilst the QCS low group 24% responded with median PFS of 8.6 months [69]. This evidence concerns the gene ERBB2 and cancer.