1, genetic family: patients with esophageal cancer have obvious family aggregation. In the same family, it can happen in the same generation or once every few generations. Clinicians have also noticed that patients with obvious family characteristics have the characteristics of severe symptoms, poor curative effect and short course of disease. 2. Alcohol and tobacco addicts: With the increase of smoking and the extension of smoking time, the accumulation of carcinogens such as nitrosamines in tobacco in the body will also increase, and the risk of illness will also increase. Drinking and smoking have synergistic carcinogenic effects. 3. Too much mold intake: A variety of molds were found in sauerkraut, wowotou and corn flour in high-incidence areas, and the mold pollution rate of grain was significantly higher than that in low-incidence areas. Pedicularis holly and Alternaria spp. isolated from grain have carcinogenic effects, and the toxins produced can cause chromosome aberration. Mold and nitrosamines have synergistic carcinogenic effects. 4, too much lye in the body: lye is a very powerful chemical in industry, which will be used in many cleaning processes, and even household cleaners contain such substances. When eating by mistake or other factors causes corrosive esophagitis, it also means increasing the chance of esophageal cancer. 5. People who ingest a lot of nitrosamines: nitrosamines are a strong carcinogen, and more than a dozen nitrosamines in 100 cause many kinds of animal esophageal cancers. It is found that residents in the high incidence area of esophageal cancer consume different amounts of nitrosamines in their diet, and it is proved that the intake of nitrosamines from the diet is directly proportional to the incidence of esophageal cancer. The content of nitrosamines in gastric juice of people in high incidence area was significantly higher than that in low incidence area. 6. Lack of nutrition, vitamins and trace elements: The lack of certain vitamins and trace elements has created certain conditions for the onset of esophageal cancer. Esophagitis, atypical cell hyperplasia and severe hyperplasia are common in high-incidence areas, which are related to insufficient intake of protein, fruits and vegetables in high-incidence areas. Lack of fruits and vegetables, minerals and vitamins in the diet will also increase the incidence of esophageal cancer, especially vitamins A and b 7. Hot eaters who often eat sauerkraut: there are more nitrite and nitrous acid in sauerkraut, and polycyclic aromatic hydrocarbons such as benzopyrene, a carcinogenic compound, are also detected in sauerkraut. The survey found that people who eat sauerkraut are more common in high-incidence areas, and the incidence of esophageal cancer is positively correlated with the amount of sauerkraut eaten. In addition, when drinking hot food, thermal injury may be a condition to promote or become a tumor.