If gastric ulcers are left untreated for a long period of time, the chance of cancer is about 1% to 3%. Most of the gastric ulcers are characterized by recurrent rhythmic pain in the middle and upper abdomen, most of which can be cured, and pathological biopsy can be performed to exclude cancer. Long-term recurring ulcers that cannot be cured need pathological biopsy to exclude cancer, to prevent delays in the condition, and should be rechecked after treatment to observe the healing of ulcers and changes, and adjust the treatment measures in time. If long-term gastric ulcers are not treated in time, the chance of developing into gastric cancer is about 1%~3%. Therefore, patients with gastric ulcers should receive treatment actively at an early stage to avoid exposure to triggering factors and to prevent the progression into gastric cancer. Signs of malignant transformation of gastric ulcer include regular change of pain, ineffective anti-ulcer treatment, emaciation, weight loss, vomiting blood, black stool, abdominal mass, positive fecal occult blood, etc. If you feel uncomfortable, it is recommended to consult a doctor in time. If you feel unwell, it is recommended to consult a doctor in time to clarify the cause of the disease and target treatment under the doctor’s guidance, and do not take medication on your own to avoid delaying your condition.