The epidemiology of oral cavity, pharyngeal and esophageal cancer outside of North America and Western Europe

Geographical variations in the incidence of oral cavity, pharyngeal, and esophageal cancer were studied, with special reference to rates in countries outside of the United States and Western Europe. Although reporting techniques differ greatly and comparisons must be made with caution, significant variations are evident. Tracing such differences often reveals possible etiologic factor for these forms of cancer. The roles are discussed of known environmental carcinogens, such as N-nitroso compounds, polycyclic aromatic hydrocarbons, and such cultural habits as smoking or chewing tobacco, excessive consumption of alcoholic beverages, as well as other possible factors in the etiology of these cancer types.