Strongly positive ER and PR of breast cancer is the result of immunohistochemistry, which suggests that the content of estrogen receptor and progesterone receptor in the body is high, and endocrine therapy is needed. After diagnosis of breast cancer, patients need to undergo pathological examination, improve genotyping, immunohistochemistry, etc., which can predict the healing of breast cancer and guide the next step of treatment. Breast cancer with strong positivity for both ER (estrogen receptor) and PR (progesterone receptor) is indicated for endocrine therapy. Premenopausal women can choose anti-estrogen drugs, such as tamoxifen; postmenopausal women use third-generation aromatase inhibitors, such as letrozole. Endocrine therapy carries risks of osteoporosis, bone fracture, and genital damage, so the endocrine therapy medications mentioned above should always be used under a doctor’s supervision.