The Unseen Fight Against Cancer
The Cancer Connection: And What We Can Do About It
X-Rays: More Harm Than Good
You Can Fight For Your Life: Emotional Factors in the Causation of Cancer
You Can Fight Cancer and Win
Although cancer is much more often curable than its popular reputation leads one to expect, the number of its victims and the sometimes morbid dread (oncophobia) of being among them make cancer a source of human distress that is reason enough for the fear it arouses.
In Latin, French, Italian, German, and English cancer is the crab—so-called, perhaps, because of the growth pattern of the most easily visible of all tumors: the rodent ulcer. Some purists (others would say pedants) confine the use of “cancer” to malignant growths of epithelial tissues, i.e., of the tissues that bound surfaces, using “sarcoma” for malignant growths of connective and supportive tissues and of the white cells of the blood. To laymen these niceties mean nothing. For them a cancer is any threateningly malignant growth.
Dr. Thelma Dunn declares that there is an urgent need for an exact definition of cancer that will include all examples of cancer and “exclude all other abnormal growths or diseases,” and she makes much of the admission of Virchow (one of the founders of pathology) that “no man, even under torture, could say exactly what cancer is.” But in this context, as in so many others, altogether too much fuss is made of matters of definition—for the very ambition to draw a dividing line such as Dr. Dunn proposes takes for granted the pre-existence of a working distinction between growths acknowledged to be malignant and others classifiable as benign. My experience as a scientist has taught me that the comfort brought by a satisfying and well-worded definition is only short-lived, because it is certain to need modification and qualification as our experience and understanding increase; it is explanations and descriptions that are needed—and these Dr. Dunn provides in abundance.
Hers is not a textbook, though; it could be thought of as a detailed invoice for the expenditure of the very large sums of money allotted to laboratory research—in 1976 a governmental grant of $396 million was spent on basic research, a fourfold increase over the grant in 1970. In its report to the president, the President’s Cancer Panel, presided over by Benno C. Schmidt, has already argued most cogently in defense of the expenditure of these very large sums of public money. Dr. Dunn’s book, which she describes as an informal report, and not for the cancer specialist, might be read as a series of appendices to this report. She writes with the unmistakable air of an insider—a professional who spent the greater part of her working life as a biologist and pathologist at the National Cancer Institute.
Dr. Dunn pours scorn on the idea that cancer is essentially a disease of civilization and the satellite notion that cancer develops in lower animals only after contact with man, but she goes on to explain the demographic circumstances that have nourished this illusion: in most backward societies and in most non-domesticated animals, early death deprives their members of candidature for cancer, the frequency of which tends to increase as life goes on. However, her excellent chapter on cancer-producing agents shows that industrial civilization cannot be exculpated, for soots, hydrocarbon tars, smokes, a number of food additives, and above all unnaturally high doses of radiation—all unknown in Arcadia—may all cause cancers. Due weight is given to epidemiological research, beginning with Percivall Pott’s (1775) classical association of cancer of the scrotum with the occupation of chimney sweep and ending with the identification of tobacco smoke as a principal cause of cancer of the lung—a discovery which has saved thousands of lives and holds the promise of saving thousands more.
More recently still, epidemiological surveys supervised by the Harvard School of Public Health have shown that an early pregnancy confers a certain degree of protection against breast tumors which lasts throughout life. This work will one day make young women reconsider the wisdom of using the Pill to postpone until later on the birth of any child they intend to have.
Dr. Dunn allows herself a few laughs at the expense of the practitioners of ostensibly more “scientific” disciplines such as chemistry and biochemistry: one biologist she refers to was astonished to learn that his (or was it her?) biochemist collaborator supposed that the secretions from the liver and pancreas emptied directly into the stomach. She has some fun, too, at the expense of simpleminded folk who believe that rats have gall bladders. She concedes, though, that an ignorance almost equally incredible can be found among pathologists. I have myself seen the eyes of a pathologist glaze over momentarily upon my expressing a wish to discuss the at that time widely canvassed possibility that normal and malignant tissues differ in respect of the isoenzymic profiles of their respective lactic dehydrogenases. But does not everyone who uses his mind often find himself stopping miraculously short at the very brink of chasms of ignorance? Test yourself, reader, by engraving upon the head of a pin all you can call instantly to mind about the following subjects: the religious causes of the Thirty Years War, the philosophy of Spinoza, Goedel’s Theorem, the nature of deep linguistic structures, and the role of Jan Comenius in the scientific philosophy of the seventeenth century. We can all catch each other out, but fortunately cancer research is a cooperative enterprise in which we all lean upon and sustain each other.
An agreeable feature of Dunn’s book is that, so far from regarding all work done before she put pen to paper as of merely antiquarian interest, she introduces many subjects by a brief historical account of how our understanding of them grew. I was particularly pleased to see that the name of Apolant, an assistant of Ehrlich’s, had not been forgotten, nor was that of Leslie Foulds. Because of its historical depth, roundedness, and intrinsic importance, the chapter on the mammary tumors of mice is perhaps the best in the book and certainly the one that best shows off the author’s wide knowledge and sensible judgment.
Dr. Dunn refers several times to the formation in 1802 of “a group of prominent English physicians” to investigate cancer and make authoritative pronouncements upon it. One such pronouncement was “that no instance had ever occurred or been recorded of cancer being cured by any natural process of the constitution.” Dr. Dunn herself adds, “less than 200 spontaneous cures of cancer are accepted as authentic”—and these are cancers of a special type in the regression of which special factors may intervene.
The acceptance of 200 cases of spontaneous regression in the face of a traditional presumption that no such phenomenon occurs encourages the belief that regressions are very much more common than such a low figure seems to indicate. So far as I am aware, the only agency that might bring about a “spontaneous” retrogression is an immunological reaction upon the tumor by the organism that bears it. Dr. Dunn writes a judiciously and temperately argued chapter on the intervention of immunological factors on the growth of tumors and outlines with complete accuracy the reasons why immunological theories have had their ups and downs of acceptability. I should like to add, however, that in my opinion the epidemiologically established relationship between pregnancy and the diminution of risk of breast cancer is quite clearly immunological in origin.
Dr. Dunn’s book comes right into the foreground of modern research. I saw with pleasure (since this is the field of tumor biology in which I work myself) that she cites some of the modern evidence which lends color to the old-fashioned belief that malignant tumors are to some degree anaplastic, i.e., re-acquire some of the characteristics of an embryonic cell. Here, perhaps, lies the best hope of the early diagnosis of malignant growths.
One cannot yet attempt a cost/benefit analysis of those hundreds of millions of dollars spent throughout the world on cancer research because all the credit entries are not yet complete. Cancer is not one disease and it will not have one cure, but the way things are going the treatment of a cancer patient is going to acquire more and more the characteristics of a research problem in which the patient, after scrupulously careful biochemical, pathological, and immunological assessments, will have a treatment or a system of treatments exactly tailored to suit his condition, by a physician competent to appraise and give due weight to all the evidence that will come before him of the tumor’s whereabouts, its degree of malignancy, and the patient’s natural power to combat it—which is likely to depend, at least in part, on the soundness of his immunological response system.
It may be that a new kind of physician will be called into being by these demands, much as a new kind of surgeon-scientist was called into being by the growth of therapeutic organ transplantation—a procedure which also makes special demands on the technical skills, knowledge, and physiological understanding of the surgeon—a demand which happily was met by the recruitment into surgery of some of the most able medical students that the schools of the country have produced. The sneery attitude toward surgeons that many physicians (particularly in England) were at one time wont to affect is one that nowadays seems most comically ill-judged and, just as many of the leading transplant surgeons today are as much at home in a laboratory as they are in the operating theater, so it may be that a new generation of oncological physicians will arise who feel just as much at home in the laboratory as in the cancer ward. Just one brilliant break is needed—akin to the first brilliant kidney transplant in the Peter Bent Brigham Hospital in Boston—and then recruits will come forward by the hundred, many of them, I shouldn’t wonder, clutching this book by Thelma Dunn in their hot hands.
Unlike Dr. Dunn, Larry Agran is an amateur, but he is so intelligent and sensible that it hardly matters. Sometimes, though, in disclaiming personal clinical authority he stands too far back from his subject: “Cancer, it seems, is not really a single disease susceptible to a single cure.” Why “it seems”?—surely no one can have tempted him to think that a contrary opinion is widely held.
Agran says that billions of dollars have been poured into cancer research in the US and throughout the world, but my guess is that the order of magnitude is 108, not 109. However that may be, he cites actuarial statistics to show that although some rare tumors (Hodgkins’ disease is one) are being mastered, recovery from the commonest and most destructive tumors—mammary and colonic—has not improved as much as this large expenditure authorizes one to hope.
What, then, is to be done? asks Agran. An early mention of Percivall Pott (see above), the culture hero of cancer epidemiology, reveals the direction his thoughts are taking, and he goes on to mention the now fully attested cancer-producing actions of radioactive substances and certain food additives and fibers. He goes on to say that the National Cancer Institute estimates that the vast majority of all human cancers—perhaps up to 90 percent*—are attributable to environmental carcinogens. “Cancer today, therefore, is actually a disease of man-made origin. What this means, of course, is that cancer is largely a preventable disease.”
Richard Doll, one of the world's foremost epidemiologists, cites a figure of only 80 percent.↩
Richard Doll, one of the world’s foremost epidemiologists, cites a figure of only 80 percent.↩