DIETARY NITROSAMINES, HETEROCYCLIC AMINES, AND RISK OF GASTRIC-CANCER- A CASE-CONTROL STUDY IN URUGUAY

To study the effects of dietary chemicals like nitrosodimethylamine an d 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine, resulting from the cooking method of red meat, on gastric carcinogenesis, a case-control study was conducted in Uruguay, a country with areas of high rates of gastric cancer. The study involved 340 cases and 698 controls, who wer e interviewed between January 1993 and December 1996. Dietary nitrosod imethylamine was associated with an increased risk of gastric cancer [ odds ratio (OR) = 3.6, 95% confidence interval (CI) = 2.4-5.5], wherea s dietary 2-amino-1-methyl-6-phenylimidazo[4, 5-b]pyridine (a potent m utagen derived from the frying and broiling of red meat) showed an OR of 3.9 (95% CI = 2.3-6.4). Both chemicals displayed independent effect s, and its interaction followed a multiplicative model with an elevate d OR of 12.7 (95% CI = 7.7-21.2). These results suggest that salted an d barbecued meat, frequent items in the Uruguayan diet, and the result ing chemicals from the cooking methods of both types of meat are signi ficantly associated with a high risk of stomach cancer.