Genetic susceptibility: 60% of esophageal cancer patients have family history. Chronic inflammation of esophagus: Long-term chronic inflammation of esophagus has a close relationship with carcinoma. Such as esophageal scar stenosis, esophageal hiatal hernia, reflux esophagitis, esophageal diverticulum, cardia loss of relaxation, etc. Influence of geographic environment, climatic conditions and soil quality: The incidence rate gradually decreases in concentric circles in our province with Yanting as the center and in all directions. Pathology: Squamous carcinoma 95%, adenocarcinoma 5%, and adenosquamous carcinoma and small cell carcinoma. Early stage esophageal cancer pathological typing Occult type: Esophageal mucosa is only mildly congested or mucosal roughness, not easily recognized by naked eyes, all of them are carcinoma in situ, which is the earliest stage of esophageal cancer. Cicatricial type: There is very superficial cicatricial on the mucosal surface, like a map, and in situ carcinoma and early invasive carcinoma account for half each. Plaque type: The surface of esophageal mucosa is slightly elevated, like psoriasis, and can invade the whole circumference of esophagus. Papillary type: The tumor forms obvious hard nodes, some are like breast, some are like polyps with short tips, protruding into the lumen.