Comparisons of the Clinicopathological Characteristics and the Expression of Tumor Biomarkers among Luminal, HER2-Enriched and Triple Negative Breast Cancer

Objectives: The aim of this study was to compare the clinicopathological characteristics and the expression of tumor biomarkers among luminal breast cancer (LBC), HER2-enriched breast cancer (HEBC), and triple negative breast cancer (TNBC) in Chinese women. Methods: According to the result of IHC staining detection, 683 breast cancer patients undergoing surgery from January 2009 to December 2010 were classified into three subtypes: LBC (ER+ and/or PR+, HER2-), HEBC (ER-, PR-, HER2+) and TNBC (ER-, PR-, HER2-). Results: Significant difference in tumor grade, tumor size and TNM stage was observed both in HEBC (P<0.0001, P=0.001 and P<0.0001, respectively) and TNBC (P<0.0001, P<0.0001 and P=0.009, respectively) when compared with LBC. The rate of lymph node metastasis in LBC was 14.4% and 18.1% lower respectively than that in HEBC (P=0.001) and TNBC (P=0.001). The Ki-67 expression in LBC was 17.1% and 13.9% lower respectively than that in HEBC (P<0.001) and TNBC (P=0.016). Furthermore, the tumor grade II/III in TNBC was significantly higher than that in HEBC (P<0.001), and the expression of p53 and EGFR in TNBC was 15.0% and 29.9% higher than that in HEBC (P=0.002, P=0.011). Additionally, the higher tumor grade was a risk factor for the expression of p53 and EGFR in TNBC. Conclusions: The distinct intrinsic BC subtypes exhibited the heterogeneity in clinicopathological characteristics and biomarkers expression. The individualized therapy of breast cancer should be more emphasized on the strategy of treatment.