A case-control study of cancer of the esophagus and gastric cardia in Linxian.

A case-control study involving interviews with 1,244 patients (758 males and 486 females) with cancer of the esophagus or gastric cardia and 1,314 population-based controls (789 males, 525 females) was carried out in Linxian, a rural county in North Central China with one of the world's highest mortality rates for these tumors. Cancer risks tended to rise with increasing intake of wheat and corn, but no association was found with adult intake of pickled vegetables, the leading a priori suspect, and risks were not elevated among those consuming low quantities of fresh vegetables or fruits. Few differences in preparation or storage of food or water were detected, although cancer patients reported less fluid intake than controls. Few persons reported drinking alcoholic beverages. Smoking was reported by 61% of the male cases and was a mild risk factor, related more to cancer of the cardia than of the esophagus. The risk was increased by 70% among those whose parents had esophageal or stomach cancer, but only slightly among those whose spouses had such cancers, suggesting that exposure early in life and/or genetic effects may be involved.