Incidence and mortality rates for stomach cancer in Canada are among the lowest in the world, with declining rates being seen in both sexes since the turn of the century. In Canada, rates are highest in Newfoundland (with diets traditionally high in salted and cured foods) and low in British Columbia. Although the overall incidence of stomach cancer is decreasing, there has been a rise in the incidence of proximal and gastroesophageal junction cancers.

Dietary risk factors are important in this disease. Risk is reduced with the consumption of fresh fruits and vegetables, and increased with higher nitrate consumption from pickled, salted, and cured foods. Refrigeration and improved food preservation (with less conversion of nitrates to carcinogenic nitrites) have contributed to the decline in incidence of stomach cancer. Other risk factors are associated with either upper or lower stomach cancer. Family history and infection with Helicobacter pylori bacteria are associated with lower stomach cancer; whereas alcohol, smoking and hiatal hernia are associated with upper stomach cancer.

Familial syndromes such as hereditary nonpolyposis colorectal cancer, Li-Frameni , familial adnomatous polyposis and Peutz-Jeghers syndrome can all be associated with gastric cancer. Hereditary diffuse gastric cancer (HDGC) is a rare disorder, probably only accounting for 1-3% of gastric cancers. HDGC is transmitted in an autosomal dominant pattern and the penetrance is 60-80%. The BCCA is involved in research on HDGC.

Reference:

1. Nomura A. Stomach cancer. In Schottenfeld D, Fraumeni JF Jr. (Eds) Cancer Epidemiology and Prevention 2^nd Ed. 1996 Oxford University Press, Oxford. PP. 707-724.