Risk Factors and Causes of Stomach Cancer
The cause of stomach cancer is unknown. Age and gender are risk factors and the disease is more common in men over the age of 55.
A diet high in salt and nitrates and low in vitamins A and C increases the risk for stomach cancer. Other dietary risk factors include food preparation (e.g., preserving food by smoking, salt-curing, pickling, or drying) and environment (e.g., lack of refrigeration, poor drinking water). A diet high in raw fruits and vegetables, citrus fruits, and fiber may lower the risk for stomach cancer.
Medical conditions that increase the risk for the disease include pernicious anemia (vitamin B-12 deficiency), chronic inflammation of the stomach (atrophic gastritis), and intestinal polyps (noncancerous growths).
Genetic (hereditary) risk factors include hereditary nonpolyposis colon cancer (HNPCC) syndrome and Li-Fraumeni syndrome (conditions that result in a predisposition to cancer), and a family history of gastrointestinal cancer. People with type A blood also have an increased risk for stomach cancer.
Acquired (not present at birth) risk factors include the following:
- Cigarette smoking
- Infection with Heliobacter pylori bacteria (a bacteria related to stomach ulcers) or Epstein-Barr virus
- Occupational factors (e.g., working in rubber and coal industries)
- Personal history of gastrointestinal cancer, previous abdominal radiation, or stomach surgery