Excess incidence of squamous cell esophageal cancer among US black men: Role of social class and other risk factors

Data from a population-based case-control study were used to evaluate the r elation between social class factors and squamous cell esophageal cancer an d the extent to which alcohol, tobacco, diet, and low income contribute to the higher incidence among Black men than among White men in the United Sta tes. A total of 347 male cases (119 White, 228 Black) and 1,354 male contro ls (743 White, 611 Black) were selected from three US geographic areas (Atl anta, Georgia, Detroit, Michigan, and New Jersey). Cases were residents of the study areas aged 30-79 years who had been diagnosed with histologically confirmed esophageal cancer between 1986 and 1989. The adjusted odds ratio s for subjects with annual incomes less than $10,000 versus incomes of $25, 000 or more were 4.3 (95% confidence interval: 2.1, 8.7) for Whites and 8.0 (95% confidence interval: 4.3, 15.0) for Blacks. The combination of all fo ur major risk factors-low income, moderate/heavy alcohol intake, tobacco us e, and infrequent consumption of raw fruits and vegetables-accounted for al most all of the squamous cell esophageal cancers in Whites (98%) and Blacks (99%) and for 99% of the excess incidence among Black men. Thus, lifestyle modifications, especially a lowered intake of alcoholic beverages, would m arkedly decrease the incidence of squamous cell esophageal cancer in both r acial groups and would narrow the racial disparity in risk. Further studies on the determinants of social class may help to identify a new set of expo sures for this tumor that are amenable to intervention.