Moreover, in HER2-mutated PDTXs, an anti-HER2 monotherapy (with either trastuzumab, neratinib, or lapatinib) delayed tumor growth, whereas a dual anti-HER2 strategy (with either trastuzumab plus neratinib or trastuzumab plus lapatinib) produced durable tumor regression [100]. The gene discussed is ERBB2; the disease is neoplasm.