If gastroscopy is normal one year ago, there is a possibility of cancer one year later. If gastroscopy is normal one year ago without any lesions, such as no gastritis, gastric ulcer, Helicobacter pylori infection, etc., in this case, the probability that the patient will develop cancer one year later is low, but it is not completely impossible. Some rare diseases such as gastric lymphoma and small cell neuroendocrine carcinoma of the stomach can develop rapidly from nothing to something within 1~3 months. These two types of tumors do not arise from the mucosal layer of the stomach, but are the result of malignant changes in other components of the stomach wall. If patients want to determine whether cancer has occurred, they should go to the hospital in time to improve the relevant examinations, such as gastroscopy, and take tissue biopsy if necessary, and be judged by the doctor according to the final pathological results. In conclusion, the probability of developing cancer after one year of perfectly normal gastroscopy one year ago is very low, but it is still possible, and patients should have regular physical examination and review, so as to achieve early prevention, early detection and early treatment.