RISK-FACTORS FOR ESOPHAGEAL CANCER IN NORTHEAST CHINA

A hospital-based case-control study of oesophageal cancer was carried out in the Heilongjiang Province, a low-risk area for oesophageal canc er in China. From May 1985 to May 1989, 196 histologically confirmed c ases and 392 controls with other (non-neoplastic) diseases were person ally interviewed in the wards of 5 major hospitals. Information was ob tained about usual consumption in the early 1980s of 32 major contribu tors to the diet in the province, socio-demographic status, smoking an d alcohol consumption. Odds ratios (OR) were obtained from logistic re gression models, and confounding was controlled by means of multivaria te models. Smoking and alcohol consumption were major risk factors for oesophageal cancer in this population. Smokers of handmade cigarettes exhibited a particularly high risk. A near multiplicative synergism w as found between smoking and alcohol consumption. There was a signific ant inverse dose-risk trend for combined consumption of vegetables and fruits; a 300-g increase per day lowered risk by 35%. Vitamin C intak e was negatively associated with risk; a 100-mg increase per day lower ed risk by 39%. Our data suggest a modifying effect of vitamin C and b eta-carotene on risk associated with smoking, but the power of analyse s was low. Salt, salt-preserved foods and pickled vegetables were not associated with increased risk. High temperature of meals and drinks w as a strong risk indicator in this population. The strength of tea and overall tea consumption were independent determinants of the risk. (C ) 1994 Wiley-Liss, Inc.