Second, for HER2‐targeted T‐DXd, the payload of T‐DXd (deruxtecan) could be released and permeate cell membranes, inducing effective cytotoxicity on neighboring tumor cells despite the expression levels of HER2, which expanded its indications for tumors with heterogeneous HER2 expression.133. The gene discussed is ERBB2; the disease is neoplasm.