The aim of this retrospective study was to evaluate whether the HScore can be used to predict all ERBB2 IHC-equivocal cases as positive or negative without the need for fluorescence in situ hybridization confirmation.<h4>Methods</h4>Image acquisition and processing tools were used on previously collected tissue slides from patients with ERBB2 IHC 2+ breast cancer from 2014 to 2023. This evidence concerns the gene ERBB2 and breast cancer.