Esophageal cancer needs to be diagnosed from the following aspects: 1. In terms of patient’s symptoms, the typical symptom of esophageal cancer is progressive dysphagia, which starts with obstruction in eating hard food, gradually develops to obstruction in eating soft food, and finally may have obstruction in eating liquid or even drinking water, and in severe cases, the patient cannot eat at all, resulting in vomiting; 2. The most critical thing is to do gastroscopy, that is, fibergastroscopy, and take pathology to clearly diagnose esophageal cancer.