Early symptoms of esophageal cancer Early esophageal cancer is limited to the mucosal layer or submucosal layer of esophagus, and there is no specific clinical symptom or no symptom in the early stage of development. Some patients may have some latent or non-specific symptoms, such as retrosternal discomfort, indigestion or transient dysphagia, or due to local spasm of esophagus caused by tumor, patients may show regular or periodic esophageal obstruction symptoms. More than 50% of early esophageal cancer has no symptoms or atypical symptoms, which can be easily ignored. The most common symptom is choking sensation in the throat, which is slow to pass through food with stagnant feeling and can disappear and recur on its own without affecting food intake, and can be asymptomatic in the interval, which can last for several years and often occurs when the patient has mood swings, so it can be easily mistaken as functional symptoms. Upper segment esophageal cancer may also show symptoms such as dry throat, itchy throat, foreign body sensation in the throat, tightness in the throat, etc. Middle and lower segment cancer may have pain like stabbing or burning, pulling pain behind the sternum, foreign body sensation in the esophagus, stuffiness and discomfort behind the sternum, etc., and the symptoms gradually worsen with the development of the disease. In addition to the same symptoms as early stage, the typical symptom of middle stage esophageal cancer is progressive dysphagia, about 90% of patients have this symptom. Because of the elasticity and expansion ability of esophageal wall, swallowing difficulty only occurs when about 2/3 of the circumference of esophagus is infiltrated by cancer. Therefore, after the appearance of these early symptoms, the disease gradually worsens over a few months and progresses from inability to swallow solid food to inability to swallow liquid food as well. The narrowing type has the most obvious and persistent dysphagia; the ulcerated type may not have obvious dysphagia; the medullary, myxomatous or intracavitary type has more severe dysphagia. Sometimes the symptoms of dysphagia may be temporarily relieved due to necrosis of the cancerous tissue. Pain as the first symptom accounts for about 10% of the total number of esophageal cancer patients, vomiting blood and blood in stool: it is rare to see this as the first symptom. Advanced symptoms of esophageal cancer Progressive dysphagia is the main symptom of most patients at the time of consultation, but dysphagia is a more advanced manifestation of the disease. For example, swollen supraclavicular lymph nodes, hoarseness, eruption and hepatomegaly. Weight loss: Weight loss can be caused by a reduction in food intake, and in severe cases it can be cachectic (manifested by extreme emaciation, deep sunken eye sockets, dry and loose skin, leaking ribs, and a navicular abdomen, which is described as a “skin and bones” state). The main clinical symptoms of patients and their incidence are as follows: ① difficulty in swallowing: 85.4%; ② weight loss: 60.9%; ③ pain: 26.5%; ④ regurgitation: 22.8%; ⑤ hoarseness: 4.4%; ⑥ cough: 2.5%. Among them, dysphagia, weight loss and pain were the most common (according to Galandiuk et al. (1986), Launois et al. (1983) and Isolauri et al. (1987), who analyzed clinical data of treated patients with esophageal and cardia cancer)