Mr. Farrell comes for his annual physical examination complaining of heartburn and bloating. He is 42 years old, of Irish background, and has worked as a carpet layer since he was 18. You question him regarding his diet and learn that he enjoys family barbecues and a generous quantity of beer on a weekly basis. Endoscopy identifies a mass at the lower esophagus. Biopsy demonstrates a poorly differentiated gastric carcinoma. Culture of the specimen is also positive for Helicobacter pylori. You are aware that Mr. Farrell's brother, who is also a carpet layer, is dying of gastric carcinoma metastatic to liver and celiac nodes at age 45. His wife states that it seems everybody has cancer.