Head and neck tumors mainly refer to cancers of organs above the clavicle, but do not include primary or metastatic malignant tumors of the central nervous system. A characteristic of head and neck cancer is that the primary focus is confined to the primary site for a longer period of time, the adjacent lymph nodes metastasize more slowly, and distant metastasis usually occurs later. Local therapies such as surgery or radiotherapy have good efficacy for early stage patients, but clinically there are sometimes cases of distant metastasis although local lesions are controlled. At this time, chemotherapy can sometimes be used to achieve better results. Head and neck tumors are often histologically squamous epithelial carcinomas that grow infiltratively to the periphery. It can metastasize to the ministerial lymph nodes. There are five treatment modalities: surgical treatment, radiation therapy, chemotherapy, endocrine therapy and immunotherapy (including herbal medicines). In developing a treatment plan for a certain tumor and its certain stage of development, these treatment modalities, in what order or in what combination, are mainly determined by the biology of the tumor, especially its tendency to metastasize early. The vast majority of solid tumors are initially confined to the organ of origin and to the lymph nodes to which they belong. They then sooner or later metastasize through the lymphatic and/or vascular system. When solid tumors are in the limited stage, local treatment modalities are available, such as surgical treatment and/or radiation therapy. After distant metastases have occurred, only systemic treatment modalities offer hope of success. The goal of chemotherapy is to bring the vast majority of tumors that have progressed to the systemic stage into remission or to act as a preventive measure against metastasis and recurrence. Temporary regression of tumors and improvement of disease pain are possible in a subset of patients, and only rarely are tumors in the metastatic stage cured by chemotherapy. When cancer is first diagnosed, the type of treatment used alone, or the type of combination therapy used, is determined by the clinical stage of tumor development and the probability of metastasis after further diagnosis. Tumors with a high probability of microscopic metastasis have a high incidence of metastasis even after seemingly curative surgery and/or radiation therapy, and long-term outcomes can be improved with chemotherapy immediately following initial curative treatment. So, how to make the tumor get effective treatment while reducing its side effects? In order to make the tumor both get effective treatment and reduce its side effects, in clinical work, as physicians and families should follow the principles when treating head and neck cancer: General principles of radiotherapy: I. Case selection: For a patient with potentially curable malignant tumor, the first treatment often plays a decisive role. If the first treatment fails, it is much more difficult to be saved by the second treatment. Therefore, for a malignant tumor patient, an ideal treatment plan should be selected for the patient based on the patient’s specific conditions, including the location of the tumor, pathological type, disease stage, and the patient’s general condition. The basic principles of selection are: maximum possible tumor regression and minimum possible damage to normal tissues and organs. A hasty decision on the treatment plan is more detrimental to the patient than a slight delay in starting treatment due to the need for examination. For a patient who decides to undergo radiotherapy, there should be a complete treatment plan, which should include the following contents: 1. There are many patients who are already at an advanced stage when they are seen. The opportunity for radical treatment is lost. If the patient’s general condition permits, palliative treatment should still be given the opportunity to relieve symptoms and improve the patient’s quality of life. 2.Treatment mode: whether it is radiotherapy alone or a combination of radiotherapy and other treatment methods, good interdisciplinary collaboration is needed at this time. Radiotherapy and surgery are both effective local treatment measures for malignant tumors at present. In comparison, radiotherapy has the potential to avoid the risk of major disfiguring surgery. It generally does not cause significant functional or aesthetic changes. Patients who fail radiotherapy still have the opportunity to be saved by surgical treatment. Most recurrences of primary foci after radiotherapy are central, and local recurrences or residual foci have a higher chance of surgical excision. Surgical treatment will allow for pathological confirmation and a full understanding of the extent of the lesion, and incomplete resection may have a chance to be saved by subsequent radiotherapy. Most recurrences after surgery are in the margins, where radiotherapy has a higher chance of controlling the tumor than in the central part of the tumor. Preoperative radiotherapy can reduce or lose the living ability of irradiated tumor cells, eliminate or suppress subclinical infiltration in the peripheral part of the tumor, shrink the tumor, and control some lymph node metastases, thus improving the surgical resection rate, reducing the local recurrence rate, and decreasing the chance of distant metastases. For cases with locally advanced stage but can still be considered for surgical resection, cases of poorly differentiated and undifferentiated cancer, cases with easy intraoperative implantation and cases with high postoperative local recurrence rate. Preoperative radiotherapy is indicated for all cases. The purpose of postoperative radiotherapy is to destroy possible residual tumor tissues and reduce or prevent local recurrence. Therefore, there are indications for postoperative radiotherapy in cases where the tumor is not completely resected or cancer cells are seen in the microscopic cut edge or the cut edge is very close to the tumor (less than 5mm), cases with high risk of recurrence, cases where the tumor extends along the perineural area and cases where the tumor tissue has spilled into the surgical field. Care of radiotherapy patients: In order to make radiotherapy patients complete the treatment according to the treatment plan, patients should be closely observed and treated accordingly during the treatment. 1.Irradiation field skin: When irradiated by high-energy rays, the skin is protected and the reaction is light because the highest dose point is located under the skin. However, when irradiated with X-rays or electron beam, the skin reaction in the irradiated field is often more obvious and becomes a factor to limit the local irradiation dose. During radiotherapy, patients should be instructed to pay attention to protect the irradiated field skin, avoid various physical and chemical stimuli, and keep the local skin dry, which can reduce the reaction. Oral care: When radiotherapy is given to otorhinolaryngology-head and neck tumors, the mucosal reaction in the oral cavity and pharynx is usually more obvious, mainly mucositis. Patients complain of local pain, which is aggravated when eating and can affect eating when serious. 3.Dental care: When irradiating the oral area, the salivary glands are included in the irradiation field, thus the amount of saliva is reduced and sticky. In addition to dry mouth, the incidence of radioactive caries increases. 4.Psychological care: Patients with malignant tumor generally have fear and pessimism, and have a lot of worries. It is extremely important to make cancer patients face the reality and actively cooperate with the treatment. No matter in which part of the treatment, medical personnel who contact patients should have positive and optimistic attitude and give spiritual support to patients. This will make the patient feel trust and security and that the doctor is actively treating him and that there is hope for a cure. Regular observation and follow up During the treatment process, we should regularly observe the changes of the disease and make necessary modifications to the treatment plan according to the response of the tumor to radiotherapy. If patients experience any discomfort during radiotherapy, we should analyze it carefully and distinguish whether it is due to radiation reaction or tumor progression, and make symptomatic treatment accordingly. Regular follow-up after radiotherapy has at least two meanings: 1. The final evaluation of the effect of radiotherapy for malignant tumors may not always be available at the end of radiotherapy. Some tumors have a long growth cycle, and after irradiation, they only lose their proliferation ability and do not die immediately. Therefore, the tumor may only shrink at the end of irradiation, and it will take some time before it completely fades away. 2. The reaction of normal tissues and organs caused by radiotherapy sometimes takes several years to manifest. The late reactions of irradiated normal tissues and organs can sometimes be very severe and affect the quality of life of patients surviving long term after radiotherapy. The evaluation of a radiotherapy regimen needs to be observed over a long period of time. The following prerequisites must be met when combining chemotherapies: 1. The chemotherapeutic agents used must be effective when treated alone. They must have different mechanisms of action, i.e., they must act at different stages of the cell cycle in order to destroy cell populations at different stages of the cell cycle. 3. These chemotherapeutic agents must have different toxicities in order to be able to use the same dose as possible in monotherapy. 4. In order to avoid long-term immunosuppression, intermittent administration is preferable during long-term treatment.