Compared with non-TN breast cancer, TN breast cancer correlated with younger age (below 35 years, p = 0.003), higher histologic and nuclear grade (p < 0.001 and p < 0.001, respectively), negative staining for bcl2 expression (p < 0.001), positive staining for EGFR (p = 0.003), and high levels of p53 (p < 0.001) and Ki67 expression (p < 0.001) (see Additional file 1). Here, EGFR is linked to breast cancer.