The pathogenesis of gastric cancer regardless of histological structure is a classic example of gene-environment interaction, and an important epidemiological aspect was the recognized association with Helicobacter pylori infection. This paper describes a case of gastric mucosa-associated lymphoid tissue (MALT) lymphoma in a young patient whose first sign of the disease was upper gastrointestinal bleeding and associated hemorrhagic shock. The patient is a 31-year-old man, diagnosed by endoscopy 10 years ago with H. pylori-positive chronic atrophic gastritis, who refused treatment to eradicate the bacterium and presents currently in the emergency room for serious upper gastrointestinal bleeding. Emergency upper gastrointestinal tract endoscopy highlights the presence of bleeding gastric tumors. It was a surgical emergency and intra-operatively the presence of invasive gastric cancer into the left hepatic lobe was noted which required total gastrectomy with the purpose of hemostasis. Immediate and remote postoperative evolution was favorable and post-operative follow-up at six months, 12 months, and 24 months showed no signs of local or distance occurrence.