Neoadjuvant therapy is a combination of therapeutic measures given before surgery, including neoadjuvant chemotherapy, radiotherapy, and radiochemotherapy. Also known as preoperative chemotherapy and radiotherapy, the concept of neoadjuvant chemotherapy proposed by Frei refers to systemic chemotherapy given prior to local treatment of malignant tumors, also known as initiation chemotherapy, as distinct from adjuvant chemotherapy given after surgery. As a treatment for solid tumors neoadjuvant therapy has made many advances in the comprehensive treatment of solid tumors of head and neck, breast, bladder, prostate and other malignancies. Compared with postoperative adjuvant therapy, its advantages are: 1. Chemotherapy is given before the tumor vessels and lymphatic vessels are damaged by surgery or radiotherapy, which can increase the local drug concentration. 2.Control and eliminate clinical or subclinical micro metastases and reduce postoperative recurrent metastases. 3.Preoperative patients are in good health and can tolerate it, and less acute toxic reactions occur. 4.Reducing the primary lesion, reducing the clinical stage, increasing the chance of radical surgery and preserving the function of organs and tissues. 5. Through imaging observation and pathological examination of surgical resection specimens, it helps to understand the sensitivity of tumor to chemotherapy drugs and facilitates the selection of chemotherapy drugs after surgery. 6.Pre-operative chemotherapy can keep the proliferation ability of tumor cells at the lowest state during surgery and reduce the medical dissemination of cancer cells during surgery.