REV

This slide shows the relative importance of the various risks and causes of cancer. It is based on a study of cancer mortality in the United States in 1981. Various adjustments have been attempted since then, but they are minor and the overall pattern remains the same and is important in setting cancer control priorities.
It is clear that most of cancer, between 2/3 to 3/4, is potentially preventable. Since comparatively less is known about diet, tobacco control is the major target for cancer prevention programs. In countries like India, 50% of cancer is oral cancer of which 90% is associated with chewing of tobacco in various forms aggravated by smoking. In North America, in contrast, lung cancer makes up 25% of cancer, and 80 to 90% is associated with smoking. Another factor important to prevention initiatives in some countries is HBV infection which leads to primary liver cancer in Sub-Saharan Africa and South East Asia. Contamination of foods by aflatoxins also contributes. Although alcohol contributes to cancer in the West, primary liver cancer is uncommon.
These figures show that cancer is a lifestyle disease. The combination of tobacco use, a high fat and low vegetable diet, and no exercise would appear to be the right combination of risk factors for both cardiovascular diseases as well as cancer - especially lung, colorectal and breast cancers!