Seen above are gastric ulcers of small, medium, and large size on upper endoscopy. All gastric ulcers are biopsied, since gross inspection alone cannot determine whether a malignancy is present. Smaller, more sharply demarcated ulcers are more likely to be benign.

Initial evaluation of upper gastrointestinal bleeding includes endoscopy. Greater potential morbidity and mortality is suggested by a systolic blood pressure <90 mm Hg, blood urea nitrogen >25 mg/dL, and hemoglobin <10 g/dL. At endoscopy several interventions can be attempted: injection with an agent such as epinephrine, thermal therapy, and mechanical placement of a clip. Two of these methods together work better than one. Medical therapy with a proton pump inhibitor to reduce acid and improve coagulation can be combined with endoscopy. Continued bleeding or rebleeding despite therapy may warrant surgical intervention.