Cancer Prevention Study II. The American Cancer Society Prospective Study.

Over the past 40 years, the American Cancer Society has led in large-scale, prospective studies of behavioral and environmental risk factors in association with cancer development. Through results of its 1952 study, cigarette smokers were found to have a 10-fold higher risk of lung cancer than nonsmokers. Cancer Prevention Study I (1959-1972) extended these results and also showed the relationship between age smoking began, depth of inhalation, smoking cessation, air pollution, body weight, etc., on all causes of death as well as specific cancer sites. Cancer Prevention Study II began in 1982 and after six years of follow-up has confirmed many earlier findings, and additionally has found: aspirin may be protective against colon cancer; persons reporting themselves to be heavy exercisers had higher standardized mortality ratios (SMR) for lung, colorectal, and pancreas cancer than moderate exercisers; more women who were long-term users of artificial sweeteners reported gaining weight during the past year than nonusers; diesel fume exposure elevated the risk of lung cancer among men ages 40-79; pesticide exposure was associated with an increased risk of multiple myeloma; and based on CPS II mortality rates, an estimated 250 million of the 1.25 billion persons living in developed countries will die because they smoke.