Breast cancer means breast cancer that has metastasized to the armpit at least at stage 2. If it is stage 1 breast cancer there will be no axillary metastasis, which usually manifests as a breast lump. If lymph node metastasis occurs in the armpit, it is stage 2. Breast cancer tumor regardless of size, direct invasion of chest wall and skin without lymph node and distant metastasis, or breast cancer tumor regardless of size, with ipsilateral internal breast lymph node metastasis, without distant metastasis is stage 3. If breast cancer stage 4, it will metastasize to other parts of the body, such as lungs, liver, bones, etc., all of them belong to breast cancer stage 4. Early stage breast cancer can seek medical treatment in time for surgical excision treatment. When the patient has axillary lymph node metastasis, according to the results of pathological examination, molecular typing, etc., preoperative neoadjuvant therapy, postoperative adjuvant therapy, endocrine therapy, targeted therapy, etc. will be carried out to reduce the probability of recurrence and metastasis after surgery.