Gastric Cancer in Ardabil, Iran - a Review and Update onCancer Registry Data

The incidence rate of gastric cancer in western countries has shown a remarkable decline in recent yearswhile it is still the most common cancer among men in Iran. Ardabil, a North Western province, was found tohave the highest rate of GC in Iran and one of the highest gastric cardia cancer rates in the world. We used themost recent data from Ardabil cancer registry to update on the incidence and mortality of GC and performedan extensive search of the English and Persian literature in Pub Med, Embase and all 5 Persian web-baseddatabases, respectively, to summarize all possible risk factors for GC in Ardabil. The age-standardized incidencerate of gastric cancer was 51.8 (95% CI: 47.8-55.8) in men and 24.9 (95% CI: 21.5-27.2) in women per 100,000.Age-standardized mortality rates for gastric cancer in this population were 32.2 (95% CI: 29.1-35.3) and 16.3(95% CI: 13.9-18.6). The gastric cardia sub-site was the most common location (32.7%) in Ardabil. Accordingto our review H.pylori infection, gastroesphageal reflux symptoms, tobacco smoking, and high intakes of salt,red meat and dairy products increase the risk of GC while diets with a high content of allium vegetables andfruits, especially citrus fruits, and consumption of fresh fish, were significantly protective against GC. Weconclude that Ardabil has the highest rate of GC in Iran and one the highest rates of gastric cardia cancer inthe world, with no evidence of decline in incidence since 2000. In addition to H.pylori infection, the epidemicof gastroesphageal reflux disease and several dietary factors may be responsible for the very high incidence ofgastric cardia cancer in Ardabil.