The survival period of patients with mid-stage breast cancer after surgery is still relatively long, with a five-year survival rate of about 80%, while the survival rate for advanced breast cancer is lower, basically around 20-30%. For patients with intermediate to advanced breast cancer, if surgery is possible, surgery should be used as much as possible, and after surgery, cancer cells may remain in the body and chemotherapy should be administered. If the patient is positive for ER and PR, endocrine therapy can also be used. Premenopausal women can take oral tamoxifen, which is an estrogen receptor antagonist, and postmenopausal women can take oral aromatase inhibitors, such as letrozole and exemestane. It is important to come to the hospital regularly for follow-up examinations and to change the treatment plan in time if metastasis or recurrence is detected early.