The authors present the case of a male patient, aged 56, operated (partial gastrectomy) for peptic ulcer 20 years ago, who is admitted for epigastric pain and distension, frequent vomiting, asthenia and weight loss. Physical examination, barium meal and upper digestive endoscopy with biopsy established the diagnosis of carcinoma of the gastric stump, due to malignant transformation of adenomatous polyps, with duodenal invasion. Completion of gastrectomy and pancreaticoduodenectomy was performed, with good postoperative results. Although the extent of resection may appear excessive, our attitude was justified by the features of the lesion and good biological condition of the patient.