Customer Reviews

Radiation from Medical Procedures in the Pathogenesis of Cancer and Ischemic Heart Disease: Dose-Response Studies with Physicians per 100,000 Population

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I am a professor of radiation biology at the Westfaelische Wilhelms-University in Muenster, Germany. German Television sent me an advanced copy of this book and asked for my evaluation of it. My opinion is that this book is a new great contribution to the scientific knowledge. The book is didactively very well organized. A must for every radiologist in the world. Gofman's results are in excellent agreement with the latest findings of scientists at the Radiation Effects Research Foundation in Hiroshima. They report in the October issue of Radiation Resaerch that in the exposed population deaths due to stroke and ischemic heart disease are significantly increased and dose related. Thus ionizing radiation is not only inducing cancer and mutations but also non malignant diseases like stroke, heart, digestive and respiratory diseases, just as Gofman's results indicate.

Millions of cases of cancer, AND millions of cases of coronary heart disease, can be prevented by means of simple, systematic changes in the ways doctors use X-rays. This is the message in this monumental book by one of the world's most distinguished authorities on the effects of radiation on health.

In spite of its formidable title and length, Gofman's book is readable by the educated public. Its analysis is brilliantly simple. Although his actual journey was far more circuitous and demanding, in effect what Gofman did was to go to the library, copy some numbers out of standard references, and plot the results on easily understood graphs. Gofman found that the number of doctors per capita varied in different regions of the country, and that death rates from various causes did, too. When the death rate for everything-BUT-cancer-and-heart-disease was plotted against doctors-per-capita, the result was (as we would hope and expect), the more doctors, the lower the death rates.

But when a similar plot was done for overall cancer death rate, the result was, the more doctors, the MORE deaths from cancer, with the most "doctor-dense" region having a cancer death rate about DOUBLE that of the least doctor-dense region. The relationship is extremely strong, both statistically and by visual inspection of the graph. Gofman's explanation: It's well known radiation can cause cancer, and doctors, so to say, cause radiation through use of diagnostic X-rays, CT scans, etc.

Contrasting with the very high doses of radiation used to TREAT cancer, most medical uses involve low doses--ones so low, according to conventional wisdom, that they have negligible effects. Gofman says that his results show that the conventional wisdom is wrong, and that simply by MEASURING the doses actually administered, and using the information to constantly and incrementally improve technique, dosage can be greatly lowered without losing any of the undoubted benefits of medical X-rays. He lists from the literature many available but little-used methods to reduce dose, generally at modest expense. "Cost is not a big obstacle," he writes. "The big obstacle is [achieving] recognition that [accumulated dose] really matters."

Gofman examined many causes of death individually. Every kind of cancer death rate he looked at (except one) INcreased with increased doctors-per-capita. And most kinds of non-cancer death rates DEcreased - with one major exception: coronary heart disease. Its plot looks very like the one for cancer.

Gofman, who has been writing about the dangers of low-dose radiation for many years, expected his cancer results, but he was startled by the heart disease graph. Turning to the literature, he found evidence going back to 1973 that small benign tumors in the walls of blood vessels are implicated in hardening of the arteries. These radiation-induced benign tumors provide a reasonable and likely explanation for his unexpected heart disease finding, one that re-emphasizes the need for better management of medical radiation.

Gofman uses his data to estimate the fraction of cases of heart disease and of various kinds of cancer that would not have happened but for use of medical X-rays. The figures vary from about 50% to more than 80%. A clincher for the soundness of his analysis is that in an earlier book, Preventing Breast Cancer (1995), using entirely different methods, Gofman estimated the proportion of breast cancers due to medical radiation to be 75% or more. The breast cancer estimate from his new book is 83%, in remarkable agreement.

Many other causes of cancer are known or suspected. How can X-rays account for such high proportions? The answer is that they do not do it alone. Most cases of cancer are almost certainly the result of multiple causes. That is, typically, several inputs are necessary to cause a cancer, and elimination of any one of the inputs can prevent the cancer. Thus, reducing radiation exposures helps prevent all the cancers that needed a radiation input of a certain size in order to occur.

The thing about ionizing radiation is that, besides being a thoroughly proven cause, it is such a controllable cause. Unlike smoking, for example, where masses of people need to change their behavior, with medical X-rays, only some medical professionals must.

The Executive Summary of Gofman's book, including his remarkable graphs, is available (free) on-line. To find it, Google: "radiation from medical procedures"

This review was originally prepared for and appeared in the January-February 2000 issue of the bulletin of the Illinois Student Environmental Network.