Current chemotherapy for breast cancer can be divided into three categories: one is preoperative neoadjuvant chemotherapy. The second is postoperative adjuvant chemotherapy. The third is rescue chemotherapy for recurrent metastasis. Neoadjuvant chemotherapy has the following effects: First, it can shrink the tumor and increase the chance of breast conservation. Secondly, it can reduce the proliferation activity of tumor and prevent the dissemination during surgery. Third, neoadjuvant chemotherapy can significantly improve the survival if the lesion disappears completely. Finally, neoadjuvant chemotherapy can understand the effectiveness of the regimen in human body and provide clear guidance for future chemotherapy. The role of adjuvant chemotherapy is to kill or inhibit micro-metastases that are currently undetected in the clinic, to improve the effectiveness of diagnostic treatment, and to improve survival rates. Chemotherapy can cause systemic adverse effects in many systems. The doctor will monitor the patient’s blood cells and give medication if necessary, and this side effect can be controlled. Second, gastrointestinal reactions. Such as nausea, vomiting, etc. We can give anti-emetic drugs, and we need patients to build confidence and actively cooperate. The third aspect is that chemotherapy can cause some inflammation of the oral mucosa and some oral ulcers and mucosal ulcers. During chemotherapy, we can pay attention to the list of diet, avoid spicy, appropriate amount of B vitamins and symptomatic treatment. The fourth aspect, hair loss, can be treated by wearing ice caps and lowering metabolism during chemotherapy. This kind of hair loss is not permanent, and most patients can regrow hair after chemotherapy. The fifth area is liver and kidney function damage. Liver and kidney function should be checked before chemotherapy, generally mild damage does not affect the subsequent chemotherapy, after the end of chemotherapy, liver and kidney function can gradually return to normal. The sixth is cardiotoxicity. Especially anthracyclines. Patients may experience panic, chest tightness, even arrhythmia and ischemic changes of the heart. Seventh allergic reactions. Acute hypersensitivity reactions are mostly seen with paclitaxel drugs and should be carried out in strict accordance with the anti-allergic pretreatment protocol provided by the doctor. The eighth is damage to peripheral nerves. Such as paclitaxel and vincristine. After chemotherapy, patients may feel numbness and tingling in their hands and feet. The symptoms can be relieved by B vitamin supplementation. Furthermore, some patients may have diarrhea, which can be identified by stool tests and treated symptomatically. There are also endocrine effects. After chemotherapy, the ovarian function may be affected and menopause may be premature. In addition, when chemotherapy is given, if the drug leaks out, it can cause some necrosis of the skin and subcutaneous tissues, and chemical stimulation of the veins can cause phlebitis, so it is recommended to establish deep vein access for chemotherapy such as PICC, infusion port device, subclavian cannula, etc. For questions related to chemotherapy, you must communicate with our professional doctors to get answers, and we will work together to finish chemotherapy for breast cancer.