ERBB2 and breast cancer: The main findings of the present study are: 1) multiple SNPs including HER2-related and HER2 non-related are identified as potential genetic markers of CTRCT in HER2 positive patients with breast cancer; 2) evidence regarding HER-2 related genetic markers is limited and somewhat contradictory 3) there is emerging evidence from gene expression profiling of mRNA markers associated with CTRCT; and 4) miRNAs represent an attractive research field for future CTRCT marker development (Fig. 3).