Etiology of esophageal cancer

The cause of esophageal cancer is still unclear, but the following factors are related to the occurrence of esophageal cancer:

1. Nitrosamines Nitrosamines are a strong carcinogen, widely distributed in the human living environment, and can also be synthesized in the human body under the action of mold. More than 10 nitrosamines have been found to specifically induce esophageal cancer in animals, with obvious tissue affinity. Nitrosamine compounds that can induce esophageal cancer in animals have been found in the gastric juice of residents in areas with a high incidence of esophageal cancer, and it has been found that the exposure level of nitrosamines in the stomach of people in different areas of incidence and different genders and age groups is consistent with the level of esophageal cancer mortality, and is positively correlated.

2. Fungal infection In a comparative study of high-incidence and low-incidence areas of esophageal cancer, it was found that the rate of grain mold contamination in high-incidence areas of esophageal cancer was significantly higher than that in low-incidence areas. Some fungi can promote the formation of nitrosamines and their precursors, promoting the occurrence of cancer.

3. Lack of vitamins Lack of vitamin A, vitamin B2, vitamin C, and insufficient intake of animal protein, fresh vegetables and fruits are common characteristics of areas with a high incidence of esophageal cancer. Changes in the content of certain trace elements such as molybdenum, selenium, zinc, copper, iron and calcium in the body and in the soil are closely related to the occurrence and development of esophageal cancer.

4. Esophageal injury, esophageal disease and food stimulation Esophageal injury and certain esophageal diseases can trigger esophageal cancer. The incidence of esophageal cancer is higher in patients with corrosive esophageal burns and stenosis, esophageal achalasia, esophageal diverticulum or reflux esophagitis than in the general population. Epidemiological surveys have found that residents in areas with a high incidence of esophageal cancer have the habit of eating hot foods, drinking strong alcohol, eating large amounts of pepper, and chewing betel nuts or tobacco. These chronic physical and chemical stimulations of the esophageal mucosa can cause local epithelial cell hyperplasia. Animal experiments have shown that diffuse or focal epithelial hyperplasia may be a precancerous lesion of esophageal cancer.

5. Genetic factors and genes Esophageal cancer has a family clustering phenomenon, suggesting that genetic factors play a certain role in the occurrence of esophageal cancer. Cytogenetic studies have found that in families with a high incidence of esophageal cancer, the number of people with abnormal chromosome structure has increased significantly. The occurrence of esophageal cancer may involve the activation of multiple oncogenes and the inactivation of tumor suppressor genes.

6. The development of molecular epidemiology of human papillomavirus (HPV) in recent years has found that HPV has the function of amplifying oncogenes C-myc and H-ras, and can cause mutation and inactivation of the tumor suppressor gene p53, indicating that HPV infection may play an important role in the occurrence and development of esophageal cancer.

In addition, with the change of medical model, the role of psychological factors in cancer has been paid more and more attention. Most studies have shown that a history of mental trauma and emotional anxiety can increase the risk of esophageal cancer.