There are four main symptoms of early stage of esophageal cancer as follows: Firstly, dry throat, chest tightness, obstruction, which is aggravated when eating. Generally speaking, at the earliest stage of esophageal cancer, patients will not feel any discomfort. With the growth of tumor in the esophagus. This obstructive feeling is especially obvious when swallowing food, because this feeling only occurs when eating and does not affect normal life and work, it is easy to be ignored. Second, foreign body sensation during eating, aggravated when swallowing dry and hard food Patients often have a foreign body sensation when swallowing food at the beginning. In the process of swallowing food, food (especially dry and hard food) passes through the lesion area to produce a foreign body sensation, and this foreign body sensation is always fixed in a certain part, as if there is something that can never be swallowed. It is often ignored. Thirdly, intermittent posterior sternal swelling and mild pain Some patients feel intermittent posterior sternal swelling or mild pain. This symptom does not occur continuously, but is mostly intermittent or aggravated after exertion and when eating quickly. This is because the esophagus itself is peristaltic at all times. Symptoms only appear when the peristalsis reaches the site of the lesion. Fourthly, intermittent stagnation or stuttering sensation when swallowing food, i.e. the patient seems to feel stagnation and stuttering at a certain place for a while, which is also non-continuous and only gradually becomes obvious after the development of the lesion. Then how should we prevent esophageal cancer? Let the germs be killed in the cradle. First of all, we should protect the esophagus by not eating overly hot, hard and irritating food. Otherwise, the mucous membrane of the mouth, esophagus and stomach will be damaged. Do not swallowing can damage the esophagus. Pay attention to oral hygiene. Any lesion in the mouth is not good for digestion, and any infection will easily spread to the esophagus. Do not eat moldy food and its products. When peanuts, soybeans, rice, flour, vegetable oil, etc. are moldy, aflatoxin can be produced. It is a strong carcinogenic substance. Eat less smoked or pickled foods. These foods contain a chemical that may cause stomach and esophageal cancers. Eat less fried foods. Change your bad lifestyle by not smoking and not drinking alcohol.