If gastroscopy was done several months ago and no abnormality was found, and the recent examination confirmed esophageal cancer, then most of them should not be advanced yet, but the exact early, middle and late stage should be determined based on symptoms, signs and auxiliary examination results. Using gastroscopy to diagnose esophageal cancer, the chance of confirming the diagnosis is still relatively high, which can reach 95%, because gastroscopy must pass through the mouth, throat, esophagus and then to the stomach, but still a small percentage may cause a missed diagnosis. It usually takes 3 months to 6 months from the onset of the tumor to the development of a symptomatic mass. Diagnosis of early esophageal cancer can be confirmed by fiberoptic gastroscopy, barium meal X-ray, esophageal mucosal exfoliated cells, etc. The most common symptoms of esophageal cancer in early stage are choking sensation in the throat, pain behind the sternum and below the glabella, sensation of food retention and foreign body, dryness and tightness in the throat, and there are usually no clear physical signs in the early stage. In late stage of esophageal cancer, the main symptoms are progressive dysphagia, food reflux, hoarseness and shortness of breath, etc. Moreover, patients can be seen to be emaciated, anemic, malnourished and cachectic. When the cancer metastasizes, enlarged and hard lymph nodes or enlarged and nodular liver can be palpated. Therefore, if esophageal cancer was not detected by gastroscopy 7 months ago and only found by recent examination, further examination is needed to clarify the stage. If there is no distant metastasis, the symptoms are not serious and only the lesion is confined to the esophagus, then it should be early stage.