ERBB2 and invasive breast carcinoma: In this study, a quantitative HER2 assay based on the Quantitative Dot Blot (QDB) method was explored to fill this unmet need.<h4>Methods</h4>Consecutive resection specimens of HER2 IHC 0 and 1+ from invasive breast cancer patients were assigned to training (n=106) and validation cohorts (<i>n=</i>119), respectively by admission time.