A subgroup analysis of the NSABP B-41 trial showed that patients with IHC 2+ tumours appeared to respond better to lapatinib and chemotherapy compared to trastuzumab and chemotherapy albeit this was not statistically significant [41], indicating a need to further assess the effect of neratinib in HER2 IHC 2+ tumours (both FISH + and FISH-) in combination with trastuzumab or other trastuzumab-based antibody conjugates in clinical trials. Here, ERBB2 is linked to neoplasm.