Smoking and Risk of Proximal Vs. Distal Gastric Cancer
Abstracts
Initial Award Abstract |
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The overall incidence of gastric cancer has declined in the United States during the past 50 years. However, the incidence of proximal gastric adenocarcinomas (including gastric cardia and adenocarcinoma of the esophagus) has substantially increased in recent years. Causes for the increase of proximal gastric adenocarcinomas are not known.
In the proposed population-based case-control study of 665 gastric cancer and 665 controls in Los Angeles County, we are contrasting risk factors for proximal and distal gastric cancers. Our main objective is to determine the direct effect of smoking. A secondary objective is to determine the role of other risk factors including alcohol intake, dietary factors, previous conditions of the stomach and esophagus, use of various medications, occupational exposure and infection with H. pylori.
A structured questionnaire was designed specifically for this study to elicit information on the lifestyle factors of interest. An in-person interview is conducted with the selfrespondent or a suitable next-of-kin if the cancer patient is deceased or too in to participate. We have completed interviews with 568 gastric cancer patients (419 selfrespondent, 149 next-of-kin) and 242 controls. Controls are individually matched to cases on age (+ 5 years), gender, race, and neighborhood of residence. The male to female ratio of cases interviewed is 2.19 to 1.00. Of the cases interviewed, 31 % were proximal gastric cancer, 38% were distal gastric cancer, and 31 % were gastric cancers without a specified subsite. Upon completion of the interview, subjects are asked to donate a small specimen of blood for determination of H. pylori. Blood specimens have been collected on 172 gastric cancer cases and 138 controls. |
