ERBB2 and neoplasm: Specifically, T-DXd demonstrated to increase immune-cells and to enhance PD-L1 and MHC class I expression on tumor cells in mouse models [56]; however slight results emerged in human cell lines affected by HER2-positive gastric cancer, where T-DXd demonstrated to provide only a modest upregulation of MHC I and CXCL9/10/11 [57].