A 57-year-old patient complains of loss of appetite, heaviness and distension in the epigastric region that are not associated with eating, belching with musty-smelling air and food, nausea, and meat intolerance. According to the patient's medical history, he has been suffering from peptic ulcer disease of the stomach for the last 18 years, the deterioration of his condition occurred two months ago. Blood test reveals moderately severe anemia, leukocytosis, and increased ESR. Fecal occult blood test is positive. Gastric secretion test detects hypochlorhydria. Esophagogastroduodenoscopy allowed diagnosing an ulcer 2.5 cm in diameter with uneven, indistinct edges in the gastric cardia on the large curvature. What complication has most likely occurred in the patient?