Unlike breast cancer, where there are high rates of concordance between HER2 expression and amplification, there is less correlation in ovarian cancer, which may be due to a number of factors such as nonstandardized HER2 testing methods, disease subtypes, or tumoral heterogeneity.11-13 Intriguingly, the retrospective analysis of the initial diagnostic specimen revealed strong HER2 IHC, suggesting an opportunity for earlier treatment with a HER2 ADC if HER2 testing had been performed. This evidence concerns the gene ERBB2 and ovarian cancer.