Smoking and Chewing of Tobacco in Relation to Cancer of the Upper Alimentary Tract

There is accumulating reliable and well-sifted evidence to suggest that the tendency for cancer generally to grow in man is about the same in most parts of the world. On the other hand, the " organ distribution" of cancer is often strikingly dissimilar in different groups of population, varies greatly from one country to another, and differs in different communities in the same geographical region. Thus, for instance, an earlier study (Khanolkar, 1950) showed that intraoral cancer was relatively more prevalent in Bombay than in New York or London. It accounted for 35.9 % of all cancer cases at the Tata Memorial Hospital, Bombay, as against 16% of cancer cases in the New York and 6.7% in London hospitals. Further, even as regards the commonest site for the occurrence of oral cancer there is a noticeable difference in various localities in India. Cancer of the lip is the commonest type of oral cancer in Bihar, of the buccal mucosa and alveolar margin in Travancore and somne parts of Madras, of the base of the tongue in During recent years a large number of studies have demonstrated that there is an association between lung cancer and the amount of tobacco smoked (Doll and Hill, 1950