Gastric Cancer – Epidemiology

Epidemiology

  • Gastric cancer is the fourth most common cancer in men and the seventh most common cancer in women worldwide.1 Stomach cancer represents 1.5% of all new cancer cases in the US.2
  • The American Cancer Society estimates that about 27,510 cases of gastric cancer will be diagnosed in the United States in 2019.3
  • An estimated 11,140 people will die from gastric cancer in the United States this year.3
  • The percentage of people with gastric cancer who survive 5 years is 31%. The 5-year survival rates range from 68% for localized stomach cancer to 5.2% for metastatic disease.2
  • Between 80% and 90% of patients present with advanced disease due to an inoperable tumor or elevated risk of recurrence within 5-years of the surgery.4
  • The average age at diagnosis is 68 years old. Approximately 6 of every 10 individuals diagnosed with gastric cancer are 65 years of age or older.2
  • The rate of noncardia gastric cancer has steadily declined in most parts of the world, mostly due to the increased use of refrigeration, greater availability of fresh fruits and vegetables, decreased reliance on salted and preserved food, reductions in H. pylori infections and smoking, and increased screening rates in high-risk countries.1
  • Factors that are currently considered predictors of poor outcomes include presenting with advanced disease, poor performance status, presence of metastasis, and serum alkaline phosphatase levels ≥100 U/L.5
  • In patients who are candidates for surgery, complete resection with negative margins is only achieved in 50% of candidates.5

Risk Factors

  • Helicobacter pylori infection. Long-term infection with H. pylori may lead to inflammation (chronic atrophic gastritis) and precancerous changes of the cells lining the stomach.
  • Mucosa-associated lymphoid tissue (MALT) lymphoma. MALT lymphoma is associated with an increased risk of developing adenocarcinoma of the stomach. MALT lymphoma is caused by infection with H. pylori bacteria.
  • Large amounts of smoked foods, salted fish and meat, cured meats, pickled vegetables, and nitrates increase the risk of gastric cancer. Diets high in fresh fruits and vegetables lower the risk of developing gastric cancer.
  • Family history/genetic factors. Individuals with a first-degree relative with a history of gastric cancer are at increased risk of gastric cancer. Certain genetic disorders are also associated with increased risk, including:
    • Hereditary diffuse gastric cancer
    • Lynch syndrome
    • Familial adenomatous polyposis (FAP)
    • Li-Fraumeni syndrome
    • Peutz-Jeghers syndrome (PJS)
  • Tobacco and alcohol use. Use of these substances increase the risk of developing gastric cancer.
  • Epstein-Barr virus (EBV) infection. EBV has been found in the cancer cells of 5–10% of individuals with gastric cancer. These cancers tend to be slower growing, less aggressive, and less likely to metastasize.

References

  1. Bray F, Ferlay J, Soerjomataram I, et al. Global cancer statistics 2018: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA Cancer J Clin. 2018;68:394-424.
  2. National Cancer Institute. Cancer Stat Facts: Stomach cancer. https://seer.cancer.gov/statfacts/html/stomach.html
  3. American Cancer Society. Key statistics about stomach cancer. www.cancer.org/cancer/stomach-cancer/about/key-statistics.html
  4. Wagner AD, Syn NL, Moehler M, et al. Chemotherapy for advanced gastric cancer. Cochran Database Treat Rev. 2017;8:CD004064.
  5. National Comprehensive Cancer Network. Gastric Cancer (Version 2.2018). nccn.org/professionals/physician_gls/pdf/gastric.pdf.
  6. American Cancer Society. Stomach cancer risk factors. cancer.org/cancer/stomach-cancer/causes-risks-prevention/risk-factors.html