ABSTRACT
This chapter discusses some of the more important parts of the digestive tract and their cancers. If food contains carcinogenic substances, the part of the body which immediately comes into contact with them is the alimentary canal. Some parts of the digestive tract are, in fact, highly vulnerable to cancer, presumably caused by dietary pathogens. Epidemiological studies also support the view that human diet probably contains carcinogenic agents. The differences sometimes cut across ethnic boundaries. Cancer of the liver, for example, is common in some parts of the world, rare in others. Similarly changes in dietary habits are responsible for the considerable changes in mortality from a given type of cancer within a few decades. From the point of view of carcinogenic influences, the digestive tract can be divided into three sections. The oral cavity, the oesophagus and the stomach can be grouped together in the first section, the small intestine constitutes the second and the large intestine the third.
