Esophageal cancer is one of the common malignant tumors in China, which is the country with high incidence of esophageal cancer and the country with the highest mortality rate of esophageal cancer. The reasons for the occurrence of esophageal cancer have not been fully understood so far. The causes of this disease are comprehensive, complex and multifaceted, which may be related to the following factors. (I) Chemical causes: Certain nitrosamines can trigger esophageal cancer. People in high incidence areas like to eat sauerkraut, which has been measured and analyzed to show that this kind of sauerkraut contains nitrite, nitrate, secondary amines and so on, and all these chemicals are the precursors of nitrosamines. The amount of sauerkraut consumed is directly proportional to the incidence of esophageal cancer. (ii) Mold contamination Some people in areas with high incidence of esophageal cancer consume moldy food more commonly, and the situation of mold contamination of food is more serious. Consumption of moldy food is also related to the occurrence of esophageal cancer. (III) Nutrition and trace elements: Looking at the high incidence areas of esophageal cancer in the world, they are usually in poor areas with poor land and nutrition, and the diet lacks vitamins, proteins and essential fatty acids. The lack of these components can make the esophageal mucosa hyperplasia and mesenchymal degeneration, which can further cause cancer. (D) Environmental and ecological conditions show that the high incidence areas of esophageal cancer are mostly arid hilly areas or mountainous areas, with less rainfall all year round and more dry seasons, soil pH is positively correlated with the incidence of esophageal cancer, and the crops in the high incidence areas are mostly dominated by arid crops, such as maize, sweet potatoes and so on, and there are few vegetables and fruits. The soil in high incidence areas contains low elements such as molybdenum, zinc, copper and manganese. (E) Localized damage to the esophagus may be one of the factors that cause cancer, as long as the diet is hot and hot. Long-standing esophagitis caused by various reasons may be a pre-cancer lesion of esophageal cancer, especially with mesothelial cell formation, which has a greater risk of cancer. It has been reported that esophagitis and esophageal cancer have a very close relationship, and esophagitis tends to occur 10 years earlier than esophageal cancer. (Long-term smoking and drinking are related to the development of esophageal cancer. According to some studies, the incidence rate of those who drink a lot of alcohol is more than 50 times higher than that of those who do not drink, the incidence rate of those who smoke more than that of those who do not smoke is 7 times higher than that of those who do not smoke, and the incidence rate of those who are addicted to smoking and alcohol is 156 times higher than that of those who do not drink and smoke. The incidence rate of alcoholics and smokers is 156 times higher than that of non-alcoholics and non-smokers. Especially those who drink strong alcohol have a higher risk of esophageal cancer. Early Symptoms: 1. Choking sensation under the throat is the most common, which can disappear and recur on its own and does not affect eating. It often occurs when the patient’s mood fluctuates, so it is easily mistaken as a functional symptom. 2.Post sternal and subxiphoid pain is more common. When swallowing food, there is retrosternal or subxiphoid pain, the nature of which may be burning, pins and needles or pulling, characterized by swallowing rough, burning or irritating food. It is intermittent at the beginning, but when the cancer invades nearby tissues or has penetration, there can be severe and continuous pain. The site of pain often does not exactly coincide with the site of the lesion in the esophagus. The pain can mostly be relieved temporarily by antispasmodics. 3, food retention infection and foreign body sensation when swallowing food or drinking water, there is a slow downward movement of food and the feeling of retention, as well as tightness behind the sternum or food adherence to the esophageal wall and other sensations, disappeared after eating. The location of the symptoms is mostly consistent with the location of the lesion in the esophagus. 4. Dryness and tightness of the throat, especially when dry and rough food is swallowed, are often associated with emotional fluctuations of the patient. 5, other symptoms of a few patients may have post-thoracic stuffy discomfort, anterior pain and Ke Rong (19) base Intermediate symptoms: 1, the most common pharyngeal obstruction and choking sensation, can be self-selected disappearance and recurrence, does not affect the eating. It often occurs when the patient’s mood fluctuates, so it is easy to be mistaken for functional symptoms. 2.Post sternal and subxiphoid pain is more common. When swallowing food, there is retrosternal or subxiphoid pain, the nature of which may be burning, pins and needles or pulling, characterized by swallowing rough, burning or irritating food. It is intermittent at the beginning, but when the cancer invades nearby tissues or has penetration, there can be severe and continuous pain. The site of pain often does not exactly coincide with the site of the lesion in the esophagus. The pain can mostly be relieved temporarily by antispasmodics. 3, food retention infection and foreign body sensation when swallowing food or water, there is a slow downward movement of food and retention of the feeling, as well as the sense of tightness behind the sternum or food adherence to the esophageal wall and other sensations, disappear after eating. Symptoms occur in the same place as the lesion in the esophagus. 4.Dryness and tightness in the throat are especially obvious when dry and rough food is swallowed, and the occurrence of this symptom is often related to the patient’s emotional fluctuations. 5.Other symptoms: A few patients may have the discomfort of the sternum, the anterior pain and the Korong (19) base V provocation bantered the Xin Renewable牡湫椭圆(19):Progressive dysphagia. There may be retrosternal pain during swallowing and spitting mucus-like sputum. Late symptoms: 1, dysphagia progressive dysphagia is the main symptom of the vast majority of patients at the time of consultation, but it is a more advanced manifestation of the disease. Because the esophageal wall is elastic and expandable, dysphagia only occurs when about 2/3 of the circumference of the esophagus is infiltrated by the cancer. Therefore, after the appearance of the above early symptoms, the disease gradually worsens in a few months, from inability to swallow solid food to inability to swallow liquid food. Difficulty in swallowing may be aggravated if the cancer is accompanied by inflammation, edema and spasm of the esophageal wall. The location of obstruction often conforms to the site of the cancer. Food reaction often occurs when the difficulty in swallowing is aggravated, and the regurgitant flow is not large, containing food and mucus, or blood and pus. Other symptoms: when the cancer compresses the recurrent laryngeal nerve, it may cause hoarseness; when it violates the phrenic nerve, it may cause eructation or phrenic nerve paralysis; when it compresses the trachea or bronchus, it may cause shortness of breath and dry cough; and when it erodes the aorta, it may cause fatal hemorrhage. When esophageal-tracheal or esophageal-bronchial fistula is complicated or the cancer is located in the upper esophagus, cervical sympathetic nerve paralysis can be produced when swallowing liquid. Signs of esophageal cancer: early signs are absent. In the late stage, there may be eruption and difficulty in swallowing. And due to the difficulty in eating, patients may be malnourished and have signs of emaciation, anemia, water loss or cachexia. When the cancer metastasizes, enlarged and hard superficial lymph nodes or enlarged and nodular liver can be touched. Jaundice and ascites may also be present. Other rare signs include enlarged inguinal lymph nodes in the skin and nodes at the abdominal white line.