There are two independent aspects to the question, "What happens next?" One is the scientific debate on the 75-percent hypothesis. The other is elimination of the overdose problem.Part 1. The Scientific Issues
Having considered each critique of which we are aware, we see no basis to change the findings of the First Edition.
Inherent uncertainties in the 75-percent estimate were and are pointed out in Chapters 38, 40, and 41. Uncertainties also characterize the competing estimates, because all estimates which use conversion factors (number of breast cancers per unit of radiation dose) must make some assumptions. In Chapter 44, we have shown why a competing estimate of 1 percent is non-credible, and in Chapters 44 and 46, we have shown why low estimates in the region of 6 percent are far less credible than our 75-percent estimate, on the basis of existing knowledge.
In general, a valid hypothesis can correctly predict some future events. However, our 75-percent hypothesis is tied specifically to absolute numbers of women of various ages, and to their breast-doses during the 1920-1960 period, and to the absolute number of new breast-cancers observed in recent years. We would like to predict that the absolute number of new breast-cancers per year would soon start to fall. It may. But failure to fall would certainly not invalidate the 75-percent hypothesis (see Chapter 47, Part 5, and Chapter 48, Part 2e).
On the basis of what is currently knowable about conversion factors, we are confident that the original estimate of 75 percent is extremely reasonable. Such an estimate is fully compatible with important roles for additional breast-cancer causes, either as independent actors or as co-factors with ionizing radiation (see especially Chapter 47, Part 7, and Index: Co-action).
Coming: A Powerful, New Reality-Check
Like every other hypothesis, the 75-percent hypothesis remains credible only as long as it is consistent with "hard reality" --- with relevant facts which are well-established. Having stressed repeatedly that the First Edition was an initial analysis (see Index: Initial analysis), we have been very actively seeking to test the hypothesis with relevant, well-established facts.
We are in now in the middle of an analysis which is completely independent of the method used in this book. Thus, it eliminates the particular set of uncertainties described in Chapters 38, 40, and 41. Of course, it has its own set of different uncertainties, for nature does not yield truth easily.
The preliminary results of this wholly separate method not only appear consistent with the 75-percent hypothesis for breast cancer, but also consistent with a large causal role for medical irradiation in other types of cancer in both women and men.
Presentation of this additional method, for breast and other cancers, constitutes the HEIR-3 Report. The study will go to press as a separate book (ISBN 0-932682-97-9, Committee for Nuclear Responsibility), probably in 1996. Readers who still have trouble believing that medical irradiation causes a very great deal of the cancer problem, may need to "think again" when they take account of this additional analysis.Part 2. Elimination of the Overdose Problem
We do not see how anyone who reads Chapter 48 can remain in denial about the radiation overdose-problem in the USA and elsewhere ... and about the feasibility of solving that problem.
Failure to give high priority to eliminating radiation overdoses would seem inconsistent with the announced determination of numerous women's groups, research grant-makers, and editorialists in medical journals, to prevent as much breast cancer as possible. The previous chapter surely shows why this is an exceedingly strange time in history to ignore radiation's continuing contribution to the production of future breast cancers.
Misinformed physicians who spread the safe-dose fallacy, or the fallacious comparison of x-ray risks with "a day in the sun," have been the chief obstacle to elimination of overdoses. We are realistic about that problem (Chapter 48, Part 4a). But the editors of our "peer-review" medical journals do not need to become accomplices. Why do they ever let the threshold fallacy pass their review? And why don't those editors lead the way in advocating a credible, independent system to stop millions of careless overdoses, and the aggregate consequences thereof?
The duty of true physicians is like the duty of democractic military leaders. Medical or military, we have a duty to do all we can to prevent unnecessary deaths and lethal screw-ups, while still achieving the bigger goal. Patients and troops trust us not to be careless with life. They trust us to make reality-checks instead of mere assumptions. And patients should be able to rely on the medical professions to do that. With respect to radiation overdosing, clearly they can't. Not yet.
We are often asked, "how many breast cancers could be prevented by getting rid of overdoses?" Of course it is impossible to know, when (thanks to the medical professions) no one even knows the current aggregate breast doses per year from all sources combined. And without knowing the number of preventable cases, it would also be impossible to know the cost per future case prevented. For the sake of argument, let's suppose that the cost of detection and treatment per case of radiation-induced breast cancer, and the cost of preventing one case of radiation-induced breast cancer by eliminating overdoses, would be equal. Which would the reader prefer?
Whenever we speculate about the cost-benefit aspects of eliminating overdoses, we must always remember that elimination of carelessness in x-ray offices will reduce x-ray dosage to all organs, not just breasts, and so there will also be a reduction of radiation-induced cases of cancer arising everywhere in the body, for both females and males.
An excellent general principle was embraced by the American Cancer Society, in an official statement of 1982 (ACS 1982, p.228). Although the statement was offered in the context of mammography ("Mammography 1982: A Statement of the American Cancer Society"), there is no basis for limiting the principle to only one type of x-ray examination. The ACS statement was:
"The American Cancer Society firmly believes that any risk, no matter how small, should be reduced as much as possible and that radiographic equipment should deliver the lowest dose of radiation consistent with producing an optimal diagnostic image."
The Bottom Line
There are not many certainties in the field of cancer prevention. But one of the certainties is this: Whatever number of x-ray-induced cancers are being "put on the shelf" (for delivery later) by today's practice, that number can be drastically reduced just by eliminating careless overdoses --- without interfering with a single useful x-ray procedure. UNSCEAR 1993 suggests that the number could be cut in half. The opportunity to have less radiation-induced cancer is staring us in the face.
With what is known today about the important role of DNA-chromosome injuries in cancer development, and about the power of x-rays at any dose-level to induce even the worst such injuries (least repairable), and with what is known from epidemiology about the induction of radiation-induced cancer, why do we continue to tolerate x-ray overdoses? In my opinion, we owe it to society to establish independent, trustworthy services which will eliminate such overdoses. And that is what I hope "happens next."
"It's no use saying `we are doing our best.' We
have got to succeed in doing what is necessary."
o - Winston Spencer Churchill, 1874-1965,
British wartime leader, and author.
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