Radiotherapy is one of the important means to treat esophageal cancer. Radiotherapy for esophageal cancer has a wide range of indications, except for esophageal perforation to form esophageal fistula with distant metastasis and obvious malignant stasis, all of them are feasible to be treated with radiotherapy. Radiotherapy for cervical and upper thoracic esophageal cancer has good effect and small damage. (1) Chest X-ray: to know whether there is lung metastasis or not. (2) Barium meal X-ray of esophagus: to determine the early and late stage of the disease and guide the formulation and implementation of radiotherapy plan. (3) CT examination: to understand the relationship between esophageal cancer itself and its surrounding organs, which is of great significance to the formulation and implementation of radiotherapy plan and the judgment of prognosis. (4) Abdominal ultrasound: to understand the condition of liver, kidney and abdominal cavity, and to judge whether there is any abdominal metastasis. (5) PT and ECT examination: select the examination according to the need to determine and understand the whole body condition. (2) Dietary and nutritional guidance in radiotherapy (1) Diet: there will be different degrees of eating pain or gastrointestinal reactions in radiotherapy, such as loss of appetite, nausea and vomiting, gastrointestinal dysfunction, abnormal taste, etc. According to the patients’ dietary preferences, there will be different degrees of pain or gastrointestinal reactions in radiotherapy. According to the patients’ dietary preferences, they can drink some acidic beverages, such as juice, cold drinks, etc., before meals, moderate activities to stimulate gastrointestinal motility, including ginger, hawthorn slices, dried fruits, etc., to stimulate secretion of the digestive glands and improve appetite. Diet should be good in color, aroma and taste, and diversified types. If the symptoms of dysphagia are reduced in the course of radiotherapy, soft, liquid or semi-liquid diet is still preferred to avoid esophageal obstruction. (2) Nutrition: It is very necessary for esophageal cancer patients to ensure nutrition during treatment. They should choose high-calorie and high-protein diet, such as soybean and milk products, chicken broth, fish broth, fresh vegetables and fruits, etc. If necessary, they should be fed with homogenized diet through nasal gastric tube, intravenous nutrition or gastrostomy. (3) Prevention of radiotherapy reaction and complications of esophageal cancer (1) Radioactive esophagitis: it occurs in the early stage of radiotherapy, usually after 1~2 weeks of irradiation. Due to the radiation damage, the mucosa of esophagus is congested and edematous, which leads to the aggravation of dysphagia and feeding pain or obstruction. This is a normal reaction, and the symptom will be gradually reduced after 2 weeks, and usually reappear in the late stage of radiotherapy. Pay attention to maintain oral hygiene, drink more water and fruit juice, vegetable juice, milk, soybean milk, etc., and slow down the speed of eating. (2) Radiation bronchitis: it usually appears after 3~4 weeks of radiation therapy. Patients show different degrees of coughing, coughing up sputum and pain, some show dry cough, irritating dry cough or dyspnea, and in severe cases, dyspnea occurs. In mild cases, no special treatment is needed, and in severe cases, anti-inflammatory and phlegm medications can be nebulized and inhaled to alleviate the symptoms. (3) Radiation pneumonitis: it mostly appears 3~4 weeks to half a year after radiotherapy. Patients have chest pain, dry cough, hemoptysis, fever, dyspnea, and high fever, chest tightness, shortness of breath when combined with infection. At this time, the patient should be bed rest, the room to maintain a certain temperature and humidity, coughing and coughing phlegm can be used to peel pears and add rock sugar boiled in water after eating pears and drinking juice, asthma can be added with Sichuan shellfish boiled and eaten. When the sputum is sticky and not easy to cough up, ultrasonic nebulizer inhalation is feasible, and anti-infective, high-dose hormone therapy is the main requirement for a long course of treatment, usually about 20 days, pay attention to keep the respiratory tract clear. (4) Bleeding: it can happen in any period of time, the precursor symptoms are not obvious, the amount of bleeding can be more or less, hemorrhage is often too late to rescue, resulting in instantaneous death of the patient. Prevention: For patients with obvious ulcers, radiotherapy should be cautious, and barium X-ray meal observation should be performed once a week during radiotherapy. For dangerous cases, the dose of each irradiation can be reduced and the total treatment time can be prolonged in order to prevent hemorrhage, and anti-infective and nutritional supportive therapy should be given during the treatment. (5) Perforation: Most of these patients have already had esophageal ulcers before treatment. After radiotherapy, the tumor recedes, the ulcer expands, and the normal epithelial cells have not yet had time to repair, resulting in perforation, with an incidence rate of less than 3%. The incidence of perforation is less than 3%. Patients may have chest and back pain, sweating, choking and fever, and the damage to large blood vessels may be life-threatening at any time. (6) Esophageal stenosis: mostly occurs 4-6 months after radiotherapy. Local dilatation should be given according to the situation. Radiation esophageal stenosis mainly manifests as difficulty in swallowing, and esophageal X-ray shows that the wall of esophagus is smooth, but the lumen is narrowed at radiotherapy. Rehabilitation after radiotherapy for esophageal cancer (1) Diet: After radiotherapy for esophageal cancer, local elasticity decreases, therefore, it is necessary to pay attention to soft food as the mainstay, avoid stimulation of esophagus by overheated, too hard or rough food, try to avoid spicy and stimulating food, too dry, too hard food and swallowing with big mouths, and it is better to chew and swallow slowly to avoid rupture and bleeding of esophagus. Solid food can be taken with water after chewing. If esophageal obstruction occurs inadvertently, the simple self-help method is: drink carbonated beverages to make the esophagus dilate accordingly due to the impact of a large number of air bubbles and form a pressure to push food out of the esophageal stenosis into the stomach, and the food can be taken out under the endoscopy when self-help is ineffective. (2) Pain: generally 1~2 weeks after the end of radiotherapy gradually recovered. The pain of patients with endoluminal therapy is generally more serious and takes a longer time to recover. It can be relieved by applying anti-infective rehydration and moderate hormone therapy. (3) Cough: it may last for several months or years after radiotherapy; in mild cases, no treatment is needed; in severe cases, anti-inflammatory, fluid replenishment, stopping cough and resolving sputum are needed. Factors affecting the effect and prognosis of radiotherapy for esophageal cancer: (1) Scope of lesion: the earlier the lesion, the better the therapeutic effect. (2) Location of lesion: the higher the location of lesion, the better the therapeutic effect. (3) Pathologic type: mycotic type has the best prognosis, followed by medullary type. (4) Dose of irradiation: 60Gy is the most effective, 50Gy and 70Gy are the next most effective. (5) Field setting: three-field irradiation is better than two-field irradiation. (6) Supraclavicular lymph node metastasis: negative patients are better than positive patients, and the prognosis of patients with lesion invasion is poor. (6) The significance of CT localization and body mold fixation in the localization of extracorporeal irradiation for esophageal cancer. Chest CT can determine the specific location of esophageal cancer, the scope of lesion and the relationship with neighboring organs. With the help of treatment planning system, the dose distribution diagrams of several different treatment plans are calculated, from which the doctor selects a more ideal plan, and then the plan is checked on the simulation positioning machine, and the patient’s posture is fixed according to the patient’s body shape, so as to ensure that the patient’s posture remains unchanged in each treatment, and to ensure that the lesion is accurately included in the irradiation range. 7, Precautions for radiotherapy of esophageal cancer: Before radiotherapy, patients should be helped to release their ideological worries; during radiotherapy, patients should pay attention to communicate with them and encourage them to talk about the discomfort in treatment in time, so as to release the psychological pressure, set up the confidence of overcoming the disease, and strive for close cooperation among patients. Let patients understand the significance of maintaining oral hygiene and quitting smoking. Diet is mainly semi-liquid or liquid food, hard food and fried food are forbidden, so as not to cause esophageal obstruction and perforation. If there is weakness, lack of appetite, nausea, vomiting, leukopenia, give symptomatic treatment. If there is local skin congestion, dry peeling, itching, do not scratch with hands or use irritating drugs. If symptoms of radiation esophagitis such as pain in swallowing and dysphagia occur, radiotherapy should not be continued; if the reaction is too severe, radiotherapy can be suspended and continued after the symptoms are relieved. If the reaction is severe, radiotherapy can be suspended until the symptoms are relieved and then continue radiotherapy. Radiation esophagitis usually disappears naturally in 2~3 weeks after the treatment. Intraoperative radiotherapy for esophageal cancer is a large-dose irradiation of the tumor and tissues around the tumor bed before or after tumor resection in the gas pedal treatment room or accelerator-para-operating room for open-heart surgery, and the therapeutic dose is 15~25Gy. Indications and contraindications of intraoperative radiotherapy for esophageal cancer (1) Indications: ① For esophageal cancer that can be completely resected, in order to improve the cure rate, it is necessary to apply radiotherapy to the tumor before tumor resection to improve the cure rate, and to improve the treatment rate. ① For esophageal cancer that can be completely resected, in order to improve the cure rate, irradiate the tumor and tumor bed around the tumor before tumor resection. (2) For esophageal cancer that can only be palliatively resected, irradiate the residual lesion and tumor bed after tumor resection. ③ For completely unresectable esophageal cancer, irradiate the mass directly without tumor resection. (iv) For those with lymph node metastasis, irradiate the metastatic foci. (2) Contraindications: ① All contraindications for open heart surgery are also contraindications for intraoperative radiotherapy for esophageal cancer. ② The tumor has invaded the aorta or trachea or left bronchus, and there is a danger of perforation. 10. The significance of preoperative and postoperative radiotherapy for esophageal cancer: Where the lesion location is high, the tumor is large or the invasion is obvious, and the patient can afford open thoracic surgery but the tumor resection is difficult, preoperative radiotherapy can improve the local control rate of the tumor and reduce the occurrence of distant metastasis. The purpose of postoperative radiotherapy is to eliminate the residual cancer tissues, and it is suitable for those whose primary foci or metastatic lymph nodes cannot be completely removed. Generally, radiotherapy is started 0.5~1 month after surgery, with tumor volume of 50Cy/5 weeks. 11.Signal of esophageal perforation during radiotherapy for esophageal cancer low fever, sore throat, fast pulse, deep or pointed niche shadow in X-ray barium contrast, etc.