At Slightly Higher Risk 
• People with type A blood and achlorhydria (lack of stomach acid).
• Males living in colder climates. 
• Those who have had part of the stomach removed because of peptic ulcers, leading to a decrease in stomach
  acids. There is a 6.5 percent incidence of tumors in the remaining stomach (gastric stump).
• Older people whose stomach lining produces less acid as it ages (atrophic gastritis). 
• Peptic ulcer and atrophic gastritis associated with Helicobacter pylori infection (for carcinoma and
  lymphoma).
• Slightly increased risk with alcohol or tobacco use.