Epidemiological studies of oral cancer.

The FDI has shown considerable interest in the oral cancer and has in recent years arranged three symposia on the subject. The incidence of oral cancer shows marked geographic differences mostly depending upon environmental factors. In the present paper the epidemiology of oral cancer is illustrated by the relative frequency to total number of cancers and incidence rates from a number of countries. Canada has the highest rate of cancer of the vermilion border, which is extremely rare among dark-skinned people. Even within one country differences may be found, a fact which is illustrated by findings from Czechoslovakia and India. In most of the studies dealing with the etiology of oral cancer tobacco usage in its various forms is shown to be the outstanding factor.