ERBB2 and breast carcinoma: ANOVA showed significant variation in age and grade, and post-hoc analysis confirmed that Group 1 vs Group 3 differed significantly in both age ( <i>p</i> = 0.001) and grade ( <i>p</i> = 0.004).<h4>Conclusion</h4>HER2-positive breast carcinomas show variability by HR status.