Objective: To investigate the expression of estrogen receptor (ER), progesterone receptor (PR), and human epithelial growth factor receptor 2 (HER2) in breast cancer, and to explore their correlation with the age of patient, and size, clinic stage, and lymph node metastasis of the tumor.
Methods: The data of 910 breast cancer, 89.4% of invasive ductal carcinoma, 1.7% of invasive lobular carcinoma, 44 cases 5% of ductal carcinoma in situ, and 4.9% of other pathologic types, 29.9% being less than 2 cm, 45.6% being 2-5 cm, and 24.5% bigger than 5 cm in size, 54.2% without metastasis in lymph node, 25.5% with metastasis in 1-3 lymph nodes, and 20.3% with metastasis in more than 3 lymph nodes respectively, were analyzed retrospectively. Immunohistochemistry was used to detect the expression of ER, PR, and HER2.
Results: The ER negative expression rate was 33.0%, and PR negative expression rate was 27.4%, and HER2 overexpression rate was 20.3%. The possibility of lymph node metastasis decreased along with the increase of age (P < 0.001). Tumor size was negatively correlated with the expression of ER and PR (both P < 0.001), and positively correlated with the expression of HER2 (P < 0.001). There was no significant difference between the situation of lymph node metastasis and the expression of ER, PR and HER2 in primary tumors.
Conclusion: As good prognostic markers of breast invasive ductal cancer, ER and PR are negatively correlated with the HER2 expression, as a worse prognostic marker. ER/PR positive or HER2 negative tumors are morel likely to be diagnosed at earlier stages.