OBJECTIVETo explore the major risk factors for upper gastrointestinal cancer in high occurrence areas of esophageal and gastric cancer in China.

METHODSFour high occurrence areas of esophageal cancer, namely Cixian and Shexian from Hebei province, Linxian from Henan province, Feicheng from Shandong province, and Zhuanghe from Liaoning province, which is a high occurrence area of gastric cancer, were selected for the study. The newly-diagnosed cases whose date of onset were after January 1st, 2009 were selected from the Cancer Registration Database in each district, and 751 cases diagnosed as cancers in lower segment of esophagus, cardiac and other subsite of stomach were randomly recruited. 2253 matched controls were selected to pair the cases at the ratio of 3:1. The relative information of the study objects were collected from the face-to-face interviews with trained staff by designed questionnaires, and the data was input by EpiData software. Statistic software SPSS 13.0 was applied to conduct both univariate and multivariate logistic regression analysis to evaluate odd ratios (OR) and 95% confident interval (CI).

RESULTSAs univariate analysis shown, 66 objects in case group had irregular diet habit; while 90 in control group had (OR = 3.177; 95%CI: 2.127 - 4.745). A higher percentage in case group (83 objects) preferred fried food in comparison with only 214 in control group did (OR = 3.190; 95%CI: 2.061 - 4.927). 369 objects in case group, but only 119 in control group had history of gastrointestinal diseases (OR = 14.660; 95%CI: 11.342 - 18.948). 282 objects in case group had history of gastroesophageal reflux disease (GERD), which was much higher than the percentage in control group (432 objects), with OR = 3.137 (95%CI: 2.546 - 3.864). All the above factors could increase the risk for upper gastrointestinal cancer. 387 objects in case group and 1278 in control group reported they preferred fresh vegetables in daily diet, which was found to be a protective factor (OR = 0.609; 95%CI: 0.473 - 0.785). As multivariate analysis shown, history of gastrointestinal tract diseases (OR = 21.420; 95%CI: 15.484 - 29.632), irregular food diet (OR = 3.097; 95%CI: 1.740 - 5.514), pickled food (OR = 3.005; 95%CI: 1.873 - 4.819), and GERD (OR = 2.261; 95%CI: 1.673 - 3.057) were found to be risk factors for upper gastrointestinal cancer; while frequent fresh-vegetable diet was a protective factor (OR = 0.562; 95%CI: 0.396 - 0.800).

CONCLUSIONIrregular lifestyle and unhealthy diet habit could be the major risk factors for upper gastrointestinal cancers among the residents from high occurrence areas of esophageal cancer and gastric cancer in China.