Immunohistochemical indices commonly used in breast cancer are as follows: 1. ER: refers to estrogen receptor, positive indicates a high level of estrogen receptor expression and good effect of endocrine therapy. 2. PR: refers to progesterone receptor, together with ER, both reflect whether the patient is suitable for endocrine therapy. 3. The higher the index, the higher the proliferation activity of the tumor, generally less than 15% is better. 5.CK5/6: cytokeratin, as a qualitative indicator, and clinical judgment of prognosis. The above are the most commonly used indicators of breast cancer, each hospital will add some different indicators according to the standard of different own pathology department, but generally these above indicators will be done.