Avoidable Causes of Cancer
Research Area: Cancer Prevention
The collaborative genius of Oxford University’s Sir Richard Doll, M.D., and Sir Richard Peto, F.R.S., produced a blueprint for avoidable causes of cancer more than 4 decades ago that largely hold true, even today.
The two researchers, Dr. Doll, a British physician, and Dr. Peto, a medical statistician, conducted an extensive evidence-based review of preventable causes of cancer at the request of the U.S. Office of Technology Assessment in several areas of concern: tobacco smoking, diet and nutrition, occupational hazards and infections.
Their 117-page report, published in 1981 in the Journal of the National Cancer Institute, cited cigarette smoking as the single most preventable cause of cancer death, causing 30% of all cancer deaths, especially lung cancer.
An earlier study had suggested that at least 20% of cancers were due to occupational exposures to carcinogens, an estimate which had sparked the government’s interest in this review. Doll and Peto, however, estimated only 4% of U.S. cancer deaths could be reliably explained by occupational exposures.
At the time of the initial review, data on diet and cancer, including “overnutrition” was indirect and unreliable, and they “guesstimated” that about 35% of cancers could be attributed to diet, with a varying range for specific sites. As for infections, the report concluded that only 10% of cancers can be traced to infections, with the caveat that many have yet to be discovered. When Drs. Doll and Peto wrote their report, the roles of herpesviruses in cervical cancer and H pylori bacteria in gastric cancer had not been identified, and the HIV/AID epidemic had not occurred.
Read more about how this landmark research held up in this 2015 article in the Journal of the National Cancer Institute.