The Secret History of the War on Cancer
By Devra Davis
(Basic Books, 505 pp., $27.95)
In 1775, Percivall Pott, a surgeon at St. Bartholemew's Hospital in London who gave his name to several diseases and conditions, published Chirurgical Observations. Although he had treated such distinguished personages as Samuel Johnson and Thomas Gainsborough, his treatise focused on the lowliest of the low. In so doing, he became the first to hypothesize what is now a widespread notion: that cancer can be caused by environmental exposure. Pott observed that:
There is a disease as peculiar to a certain set of people, which has not, at least to my knowledge, been publickly noticed; I mean chimney-sweeper's cancer. It is a disease which always makes its first attack on, and its first appearance in, the inferior part of the scrotum; where it produces a superficial, painful, ragged, ill-looking sore, with hard and rising edges: the trade call it the soot-wart. I never saw it under the age of puberty, which is, I suppose, one reason, why it is generally taken, both by patient and surgeon, for venereal.... The fate of these [chimney sweeps] seems singularly hard: in their early infancy, they are most frequently treated with great brutality, and almost starved with cold and hunger; they are thrust up narrow, and sometimes hot chimnies, where they are bruised, burned, and almost suffocated; and when they get to puberty, become peculiarly liable to a most noisome, painful, and fatal disease.... The disease, in these people, seems to derive its origin from a lodgement of soot in the rugae of the scrotum, and at first not to be a disease of the habit.
The narrow, snaking chimneys in London could be cleaned only by hand by small naked children, who were mostly orphans aged four to seven. After a latency period of ten to twenty-five years, these poor sweeps developed scrotal cancer. Scrotal cancer was unique to the chimney sweeps of London; it rarely occurred in the sweeps in Germany or the American colonies. Some attributed it to the English climate. Pott's brilliance was to note that the soot was lodged in the scrotum and that sweeps in other countries wore protective clothing that prevented this. It also turned out that because the sweeps rarely bathed, usually only once a year, the soot stayed in place for months on end.
More than 150 years later, it was discovered that the coal used in England had a higher content of the cancer-causing agent identified in 1933 as 3,4- benzopyrene. Long after Pott's observation, many other agents, from synthetic dyes to vinyl chloride, from diesel fuel to X-rays and tobacco, were identified as causing cancer. Devra Davis argues that not enough attention has been given to these environmental toxins--and, more sensationally, that much effort has been devoted by corporations and establishment scientists to covering up the harm that they cause.
In the age of the Internet, any book that claims to be a "secret history" should immediately raise suspicions, and The Secret History of the War on Cancer certainly does. When Stasi files are discovered, when presidential papers or tapes are unsealed and released, scholars are able to reveal important historical secrets. In the field of cancer, when Stanton Glantz of the University of California at San Francisco received a box of confidential tobacco-company records and then published The Cigarette Papers, he exposed long-held and important secrets about the cover-up of the connection between cigarettes and lung cancer. Davis has similar muckraking, scandal-mongering ambitions--but she offers no such discovery, no unsealing or publication of confidential or hidden records. There are no secret documents from a chemical company revealing that its products cause cancer or that it suppressed damning data. There are no toxicology test results long concealed by the government revealing that some common chemicals or products cause cancer.
So there is not much that is secret about this "secret history." Nor is Davis's book even a history, in the sense of conveying a systematic, coherent narrative of events related to the fight against cancer over time. While the overall organizational structure of the book is unclear, it certainly is not a chronological record of events related to battling cancer. Neither is it a critical examination of the origins of President Nixon's "War on Cancer" and its subsequent evolution; nor does it track how thinking about the causes, the treatment, or the prevention of distinct cancers has evolved over time.
In fact, it is unclear what exactly Davis is up to, other than trying to stoke unfocused fear about the oncological consequences of the environment. The book bristles with provocative questions. "Why are so many people in their thirties and forties in many industrialized countries coming down with often fatal cancers of the bone marrow and pancreas--diseases that used to occur only in those in their sixties or older?" "Could their shared disease have something to do with the pesticide-sodden wheat and cornfields of Illinois, and the huge grain silos surrounding their small town?" "It could be that people who work as scientists and physicians exercise more and drink less and thus don't die of heart disease. But why do so many of them die of cancer? Could something about the things people do to become or to work as scientists and doctors affect their risk of cancer?" "Electricians, railway workers, telecommunication line workers--in a striking number of industries men have greater risks of breast cancer. How can we know whether electromagnetic fields are responsible for these differences?... What about the growing number of young children and teenagers who have their own cell phones, despite the fact that Scandinavia and many other countries warn that children should not use cell phones at all?" The implications of all these questions are certainly frightening--but Davis has to admit in almost every case that we do not know the answers.
Probably the most interesting and worthy topic treated by Davis concerns the question of how scientists evaluate different potential carcinogens. She notes that each chemical or other potentially toxic agent is tested alone for whether it causes cancer, even though people are frequently not exposed only to one potential cancer-causing agent at a time, but to many simultaneously. So while low levels of a particular chemical may be safe alone, when people interact with it in combination with other chemicals it is often unclear if there is a synergistic effect. Davis raises this important point very early in the book, but she never explores it in any detail.
Instead she prefers to focus on a series of claims that are true and disturbing, but hardly new and revealing. The American approach to cancer, she maintains, is excessively focused on treating the disease once it has occurred and too little focused on preventing the disease in the first place. Going back to the start of the twentieth century, some cancer researchers, including famous and important ones, have been employed by companies to evaluate the toxicity of compounds, and often they tailored their results to the companies' interests or they never publicized their results. To pursue their own economic interests, companies--oil, asbestos, chemical, and other--concealed information showing that their products caused cancer; or worse, disposed of their industrial pollutants in ways that contaminated the environment and exposed people to extremely high levels of toxic agents. These are all disgusting and dangerous practices, to be sure. But after Love Canal and other scandals, as well as the establishment of the need for more than five hundred Superfund sites, such tales do not amount to the shocking revelation of terrible secrets. Moreover, as Davis herself notes, other books, such as Robert N. Proctor's Cancer Wars: How Politics Shapes What We Know and Don't Know About Cancer and Gerald Markowitz and David Rosner's Deceit and Denial: The Deadly Politics of Industrial Pollution, cover these issues more effectively.
To begin to evaluate a book on the history of cancer, it is important for us to be clear on what we do know about cancer. First, it is a disease of aging. It increases exponentially as people grow older, with a take-off after about thirty-five years of age. When your friends shake their heads and observe that "more people seem to be getting cancer than they used to," that vague awful feeling is simply the result of selection bias. All of us are getting older, and an older population is more prone to getting cancer. Aging, not the rate of cancer, is providing the false impression.
So what does cause cancer? Cigarette smoke contains about 4,000 chemicals, including sixty known carcinogens, and accounts for about 25 to 30 percent of cancers. The other major causes are diet and lack of exercise. High-fat and high-calorie diets, obesity, and sedentary lifestyles contribute another 30 to 35 percent. The expanding obesity epidemic has disturbing implications regarding a future rise in the number of cancer cases. Genetics is a relatively small factor, having a causal role in only about 5 to 10 percent of cancers. Ultraviolet radiation in sunlight causes melanoma. Infections can also cause cancer: the human papilloma virus causes cervical, anal, and other cancers, and hepatitis viruses cause liver cancer. These viruses tend to be much more important as causes for cancer in countries outside the United States.
What, then, about toxic chemicals? The Berkeley biologist Bruce Ames, renowned for developing a rapid screening test (the Ames test) to determine whether chemicals cause mutations in DNA and thus might cause cancer, has argued that "past occupational exposures, a major part being asbestos exposure in smokers, might cause about 2 percent of current [human] cancer; industrial or synthetic chemical pollution causes less than 1 percent, in my view." As best as I can tell, Devra Davis never mentions Ames or these figures. But even if Ames's estimate is excessively low, altogether our chemical environment cannot account for more than 5 to 10 percent of cancers.
The overwhelming fact is that, despite the profusion of chemicals and other potentially toxic exposures in modern life, Americans are living longer--a lot longer. In 1900, the average life expectancy of Americans was forty-nine years. By 1950, it was sixty-eight years, and today it is more than seventy-eight years. Granted, it could be higher. The Japanese live more than four years longer than Americans, and even the French live an average of eighty years--but no one thinks this is because they are exposed to fewer chemicals and other toxins in their environment. Probably the primary factor in their good fortune is diet: they eat more fruits, vegetables, and fish, and drink more wine, and consume fewer calories overall.
Since 1930, when the United States began collecting statistics on cancer, the number of new cancers, and of deaths from cancers, had been increasing. This was mainly due to the spread of smoking. After the Surgeon General's report in 1964, which linked cancer and smoking, rates of smoking in America declined from about 43 percent of the population to about 21 percent of adults today. The result is that since 1992, the number of Americans getting cancer and dying of cancer--adjusted for the aging of the population--has been dropping. The total decline is about 8 percent over the last thirteen years.
The fact that cancer rates are dropping while life expectancy is increasing makes it extremely difficult to contend that the profusion of chemicals, cell phone towers, and other worrisome carcinogens are making Americans much less healthy. Indeed, it is fair to say that Americans are healthier now than they have ever been. This might change, of course--but mainly because of obesity.
This does not mean that certain chemical and environmental exposures cannot cause deadly cancers, not at all. Benzene, formaldehyde, vinyl chlorides, and other toxins might increase the number of people contracting specific types of cancer. Yet these divergent trends mean that excessive concern about cancer- causing chemicals is misplaced. Overall, these numbers emphasize that the impact of these toxins cannot be substantial. If Davis truly wishes to warn Americans about the genuine risks of cancer, she should put her fingers to the keyboard and write The Secret History of McDonald's.
Ron Herberman is a renowned cancer researcher, the first director of the University of Pittsburgh's Cancer Institute. In the 1970s, he showed that natural killer cells in the immune system destroy cancer cells and keep cancers from spreading. Like many teenagers growing up in the 1940s and 1950s, especially those with a scientific bent, Herberman and his brother built and flew model airplanes, tinkered with cars, and worked in scientific laboratories. Decades later, both brothers developed chronic lymphocytic leukemia (CLL), a slow-growing cancer of immune cells.
After telling Herberman's story, Davis asks the right questions: "When two brothers from the same family with no known history of disease develop the same disorder of the blood and immune system, we have to ask, Is this just a coincidence? Is it some statistical fluke? Or did something happen to each of these men earlier in life to put them at risk of cancer?" But she never gives the reader a coherent picture of how scientists might answer these questions-- how they might figure out whether genetics, or exposure to glue, benzene, formaldehyde, saccharin, diesel, pesticides, or radiation causes CLL or any other cancer; or whether two brothers getting the same cancer is just the consequence of the law of large numbers.
Davis makes a mistake that is all too common in pop-science literature: she focuses on narrative at the expense of data and analysis. Stories such as Herberman's may be stirring, but finally they are not very helpful in trying to figure out whether radiation, a chemical, or another agent has caused cancer. Anecdotes may spark the idea that some chemical exposure is linked to a particular cancer, but for the scientist that is all they can establish. They certainly cannot prove a causal link. Why? For one thing, there is the phenomenon known as recall bias. When people get cancer, they immediately want to know, "Why me?" So they rummage through their past looking for something to explain the disease. I have had patients suggest they got liver cancer from a punch in the stomach a month before, or colon cancer from a severe case of traveler's diarrhea a few years back. When people suffer, they are generally desperate for a quick explanation for their suffering.
There is the additional problem of selection bias. The way researchers collect samples of people with cancer to study can be easily biased. Recruiting people who have cancer and have some common characteristic--say, living near each other--is not likely to generate a random sample. This method necessarily leaves out most of the people who were exposed to an agent but did not get cancer. Moreover, it would be unethical to determine if a chemical causes cancer by conducting a randomized trial in which half the people are exposed to it, so as to see whether they develop more cancers than those not exposed. Instead, researchers must piece together the puzzle while avoiding both recall bias and selection bias.
Over the years, the International Agency for Research on Cancer has codified seven criteria that, when taken together, can be used to confirm (or to refute) whether a particular exposure to a chemical, radiation, or some other agent actually causes cancer:
1. The link or association between the exposure and cancer is strong.
2. The risk of cancer increases with more exposure to the agent.
3. Multiple studies by different investigators with different groups of people come to the same finding.
4. The exposure to the agent came
before the cancer.
5. There is a plausible biological explanation for how the agent would cause the cancer.
6. The link is specific, and the agent causes a specific type of cancer.
7. The link fits together with what we know from other studies.
Some of these criteria are less necessary than others: occasionally, for example, a single agent can cause multiple cancers. X-rays are such a case.
Now consider a controversial example that has concerned the United States and many other countries for three decades--an environmental example. Does electromagnetic radiation from high-voltage power lines cause cancer, particularly childhood leukemia? Ionizing radiation, such as X-rays or the sun's skin-cancer-causing ultraviolet light, are high frequency and have sufficient energy to break chemical bonds in DNA, thus causing cancer. Microwaves and infrared light can only tumble and vibrate molecules, which is essentially the same thing as heating them up; thus the safety of microwaves can be determined by considering the safety of other ways of heating a compound. On the other hand, power lines do not produce high-energy radiation. They produce very low-energy electromagnetic radiation that cannot break chemical bonds or even heat things up--so-called non-ionizing radiation. And because power line electromagnetic fields are low level, their power decreases rapidly in a matter of a few feet.
So can such low-energy radiation cause cancer? The controversy over power lines and cancer goes back to the 1970s, when two researchers from the University of Colorado were puzzling over a collection of childhood leukemia cases in the Denver area. They identified children, under the age of nineteen, who had died of cancer between 1950 and 1973, and then matched them with children born in the same month and county as the children who died. The researchers then went to the houses of the children-- the house of birth, the house of death, or another house--and drew, as the researchers reported, "a small map of the electrical wires and transformers in the vicinity.... Distances were measured from the part of the house nearest the wires to the wires." The researchers found that 44 percent of these children who died of cancer had a stable residence near power lines, while only 20 percent of the control children did--a statistically significant difference. One problem that the researchers noted with their findings was that proximity to the power lines was associated with many different types of cancers: "Such a wide association with different types of cancer is not characteristic of known carcinogens such as ionizing radiation; thus the broad association observed here suggests that the [power line]-cancer relationship may not be a causal one." Remember criterion 6.
Over the years, people began reporting associations between this low-energy radiation from power lines and a whole host of conditions--Alzheimer's disease, Lou Gehrig's disease, breast cancer, depression, miscarriage, even suicide. Then, in June 1989, The New Yorker ran a series of three long articles by Paul Brodeur titled "Annals of Radiation: The Hazards of Electromagnetic Fields," which argued that crusading researchers had discovered the important link between power lines and cancer, but that the establishment--from the military to cancer doctors to the electric industry--was trying to deny the breakthrough, to cover it up. The report was, to put it mildly, scientifically inaccurate. It contained what an editor at the New England Journal of Medicine characterized as "fanciful" explanations for how the radiation caused the cancer.
In the last three decades, more than one hundred studies conducted in many countries, from England to Sweden to Australia to the United States, and costing hundreds of millions of dollars, have examined the link between power lines and various diseases. Several things have become clear. The association between power lines and all the diseases except childhood leukemia is unproven and probably non-existent. Multiple organizations, including the World Health Organization, the International Agency for Research on Cancer, and the European Union's Scientific Committee on Emerging and Newly Identified Health Risks, all cast doubt on the links, suggesting further research. The British Health Protection Agency wrote that "there is no clear evidence of a carcinogenic effect of ELF EMFs [extremely low frequency electromagnetic fields] in adults... . Studies of occupational exposure to ELF EMFs do not provide strong evidence of association with neurodegenerative disease [such as Alzheimer's and Lou Gehrig's diseases].... Studies of suicide and depressive illness have given inconsistent results." Remember criterion 3, and the need for consistent results across multiple studies.
The strongest evidence for the alleged causal relationship is childhood leukemia. But in this case everyone agrees that the data fail several of the seven criteria. Most importantly, no one has been able to come up with any plausible theory, much less experimental evidence, for how this very low-energy radiation could actually affect DNA and cause cancer. Higher power magnetic fields can affect nerves and muscles, disrupting the conduction of electrical impulses. But as a World Health Organization report put it, for these low- energy fields that come from power lines, "there are no accepted biophysical mechanisms that would suggest that low-level exposures are involved in cancer development. Thus, if there were any effects from exposures to these low-level fields, it would have to be through a biological mechanism that is as yet unknown." Physicists laugh at the idea. Robert Park of the American Physical Society, a pretty hard-headed scientist, regularly lampoons this link in his blog, "What's New?" A failure on criterion 5. In addition, all studies with animals have failed to show any link between this low-level radiation and cancer. Finally, criterion 2 suggests that there should be an increasing frequency of cancer with more exposure to the low-energy radiation, but this has not been shown.
So the entire controversy comes down to epidemiological studies. In 1996, a committee at the National Academy of Sciences comprehensively reviewed the data, concluding that these epidemiological studies suggested that there were twice as many cases of leukemia among children who lived near power lines. But like the original study from Denver, these studies have tended to suffer from three serious flaws. Many of the studies estimated radiation exposure by measuring the distance from a power line to a house, but at best this is a proxy measure. What we need are actual measurements of radiation levels in the house. Moreover, in many of the studies there was no blinding--that is, the researchers measuring the distance from the power line to the house or the radiation levels in the house already knew whether the child who lived in the house had cancer or not. This is not the best method for ensuring objective data collection. And finally there was selection bias in choosing which cancer victims were included.
To overcome these flaws, the National Cancer Institute undertook a thorough study. Researchers at the NCI selected all children with acute leukemia under fifteen years of age living in nine states who were in a cancer registry. They sent blinded technicians who did not know which children had cancer to actually measure the radiation levels in each child's house over a twenty-four-hour period. They were rigorous about getting into almost all the houses in which the children lived during the five years before their diagnosis. And the measurement of radiation was made very shortly after the diagnosis of cancer. The results? There is no significant excess risk of childhood leukemia associated with actual exposure of the children to radiation in their homes.
Maybe the NCI study is wrong. Maybe the animal studies are wrong. Maybe physics is wrong, and there is some as yet undiscovered mechanism by which these low-energy radiation fields do damage to DNA. How big a cancer problem would exposure to radiation from power lines be? It is a tragedy, obviously, for a child to develop leukemia, although thanks to medical advances over the last fifty years, the disease is now curable in 70 to 80 percent of cases. But from a public health perspective, how big a problem is low-energy electromagnetic radiation from power lines?
Each year in Britain there are five hundred cases of childhood leukemia. It is estimated that even doubling the risk of leukemia for children who live near power lines would increase the number of cases of childhood leukemia by two to five. An independent body studying the problem--and funded jointly by the British government, the electric industry, and the charity Children with Leukemia--concluded that even if all precautionary measures were taken, even if families and schools were moved away from power lines, and power lines were relocated and redesigned to reduce low-energy radiation emissions, "it would be impossible to evaluate the effectiveness of this intervention, as the small reduction in the number of cases would be undetectable." That is, such a small number of cancer cases would be prevented that it would be drowned out by the fluctuation of cases of childhood leukemia from year to year. I have not seen comparable numbers of cancer reduction in the United States; but extrapolating from the British data, each year there might be a reduction of twenty cases among the 3,900 or so childhood leukemia cases in a population of more than sixty million children under fifteen years of age.
In recent years, similar controversies have emerged concerning cell phone towers and base stations. The data are much the same. As Environment, Health and Safety Online, a reliable and responsible website, puts it, "The strength of these fields can decrease to almost undetectable levels at the site property line. Even the peak levels seen are thousands of times lower than the limits set for human exposure to radiofrequency EMFs (electromagnetic fields).... Currently, there is no significant indication that chronic exposure to the EMFs around cellular sites has any potential to be hazardous to human health."
The concern about cell phone handsets is more plausible. They do emit microwave radiation, and they are used close enough to the body to heat up cells that could cause damage, and possibly cancer. So what do we know about cell phones and cancer? There are many studies of the issue. The best of them come to opposite conclusions, although the preponderance of evidence is against the link with cancer. A Swedish study followed 905 adults with brain cancer, and reported that those with more than 2,000 hours of total talk time had a higher rate of brain cancer on the side that they held their phone. Unfortunately, they interviewed people with cancer and asked them about their cell phone use: recall bias--the "why me?" problem--could easily color their reporting. Two other studies, one from Britain following brain cancer patients and one involving more than 420,000 cell phone users in Denmark, showed that there was no association between cell phone use and brain cancer. As one researcher put it, "As the body of evidence accumulates, people can become more reassured that [cell phone handsets] are safe, but the final word is not there yet."
Does any of this come out in Devra Davis's book? The Secret History of the War on Cancer avoids engaging in a systematic analysis of whether low-energy electromagnetic radiation poses a serious public health risk. Davis provides a table that summarizes three studies of workplace exposure to electromagnetic fields and notes that some well-respected researchers "believe a growing body of evidence shows that there's a serious problem." She points out that the World Health Organization has classified EMF as a possible human carcinogen. But Davis never mentions or analyzes the NCI study or other studies that show no association, or the lack of a biological mechanism to account for how this low-energy radiation could cause cancer, or the animal data. Nor does she ever note what a small number of additional cancer cases would result even if non- ionizing radiation from power lines did cause cancer.
Most importantly, Davis--like many other people obsessed with cancer--does not put these risks in context. Consider the cell phone handsets. Rates of brain cancer have remained remarkably steady despite the advent of the cell phone in 1984. In fact, incidence rates slightly dropped from 6.9 cases per 100, 000 people in 1985 to 6.5 in 2004. Actual incidence counts reflect this trend: in 1997, when only 55 million cell phone subscriptions existed in the United States, the American Cancer Society reported 17,600 new diagnoses and 13,200 deaths due to brain cancer. In 2006, when the number of cell phones in use had quadrupled to more than 200 million, there were 18,820 new cases and 12,280 deaths attributed to brain cancer. And this occurred even as the overall U.S. population increased by more than 33 million between 1997 and 2006. On the other hand, each year there are 2,600 deaths and 330,000 injuries caused when car drivers use--and are distracted by--cell phones. If we really care about people's health, which problem should vex us more: cell phones causing brain cancer or cell phones causing car accidents?
Although she wants "the establishment" to shift its focus from cancer treatment to prevention, Davis cannot even embrace the successes already achieved in the public health fight in the screening and prevention of cancer. In the early part of the twentieth century, cervical cancer was the number-one cause of cancer deaths among American women. It remains the leading cause of cancer deaths in many developing countries, such as Zimbabwe and Uganda. In 1928, Georgios N. Papanikolaou, a Greek physician who was working at New York Hospital and Cornell Medical School, developed the cervical smear that has come to be called the Pap smear. The technique allowed doctors to see cells that were being sloughed off the cervix, and to distinguish normal cells from pre- cancerous and cancerous cells.
The Pap smear was not immediately embraced. The medical profession was slow. The test had not yet been shown reliably to diagnose cancers at earlier stages or actually to reduce mortality from cervical cancer. And the test clashed with social mores. As Davis puts it, having women "lie down with their skirts up, their underwear off and their legs apart" and permit an unrelated male to peer into their genitals was hardly socially sanctioned. Still, in the 1930s, the American Society for Cancer Control (ASCC) mobilized women to fight cancer, especially cancer of the cervix. It launched what Davis calls "an unprecedented campaign for public awareness of a disease seldom discussed in polite company."
Through the 1940s and early 1950s, there remained considerable controversy about, and resistance to, the Pap smear, much of it driven by professional turf issues. Physicians, ever concerned about control and protecting their procedure- driven income stream, opposed having medical technologists do Pap smears. By the 1950s, though, irrefutable data had accumulated to show that the Pap smear really could reduce cancer deaths, and soon thereafter sufficient professional and public pressure developed to overcome the resistance of doctors. In 1957, the American Cancer Society (ACS) launched a national effort to promote Pap smears. The result has been nothing short of dramatic. In 1930, cervical cancer caused nearly forty deaths each year per 100,000 women. By 1970, the rate was down to fifteen, and by 2000 2.3 deaths per 100,000 women--a mere 5 percent of the original.
While doctors and the ACS were pushing screening, researchers were looking to find the cause of cervical cancer. By the mid-1970s, epidemiological studies suggested that cervical cancer was a sexually transmitted disease, and researchers hypothesized that human papilloma virus was a cause, if not the cause. In the early 1980s, researchers were able to establish that of the more than 100 different papilloma virus strains, two--HPV-16 and HPV-18--were "high risk" and accounted for approximately 70 percent of all cervical cancer cases. Researchers were then able to work out the precise proteins that these particular viruses used to transform normal cervical cells into cancerous ones. Multiple trials were undertaken to show whether a vaccine against HPV could prevent pre-cancerous cervical lesions and cancer. In June 2006, the FDA licensed a vaccine called Gardasil, produced by Merck & Co., to protect women ages nine to twenty-six against HPV-16 and HPV-18. (This vaccine also protects against HPV-6 and HPV-11, which account for 90 percent of genital warts but do not cause cancer.)
In a span of only eighty years, then, we have witnessed the development and widespread use of a simple screening test, followed by the development of a vaccine that, if widely deployed, can substantially eliminate what was once the leading cause of cancer deaths among women. Like any human achievement, this one had to overcome scientific and technical obstacles, as well as the obstructions of ego, professional status, and greed. Widespread screening could have been introduced as much as fourteen years earlier, had it not been for these human obstacles; but anyone concerned about women's health, and working to switch the emphasis from treating cancer to preventing it, really should celebrate.
What is Davis's view? Only negative. She emphasizes the internal politics and turf battles. She asks why the vaccine is recommended for pre-teenage girls when "very few [pre-teens] were in these trials" that showed its effectiveness. "What about boys? Why are we prepared to vaccinate young girls but not young boys who can spread [the virus]?" And she goes on to assert that "no one is expressing concerns about the health of gay men or about prospects [of using the vaccine] to reduc[e] laryngeal cancer [that is also caused by papilloma viruses]." These are legitimate questions. And contrary to Davis's assertion, and certainly contrary to her tone of lonely dissent, these issues are in fact part of an ongoing and very mainstream policy debate. But in some real sense they are all secondary issues if the subject is the "war on cancer." What is genuinely significant here is that the history of cervical cancer is the very model of what we should want to achieve. Medical science has beaten this disease--not by treating it with expensive and toxic chemotherapy, but by preventing it with a safe and painless vaccine. Davis should be pouring champagne instead of squeezing sour grapes.
The Secret History of the War on Cancer is a hysterical and exasperating book. It has no overall structure and it repeats itself in the sloppiest ways. It meanders into stories and themes that have no obvious pertinence to cancer and the war on cancer. And worst of all--this being a protest, after all, against the state of medicine and science--are its New Age tones. A well- trained and reputable cancer epidemiologist might be expected to produce a book based on research and data rather than unsubstantiated claims and anecdotes. But throughout The Secret History of the War on Cancer there is a continuing homage to "treatments" that have not even been subject to serious research, much less proved safe or effective. Davis ends the chapter titled "Doctoring Evidence" by recounting the experience of people, such as the husband of Donna Karan, in using "yoga, meditation, massage, acupuncture, herbs, detoxing systems and prayer" to fight cancer. Even worse, she seems to argue against the need to evaluate these "treatments" through research: "For new herbal and nutritional remedies against cancer, or even for new uses of the soothing sounds and relaxing smells of aromatherapy, we can't persuade patients who've been told they will die to agree to sit through a trial they may not see the end of."
The notion that these "treatments," especially the herbal and nutritional ones, might help, and so need not be subjected to a research trial, is dangerous. Many such agents are unregulated and contain unknown ingredients. More importantly, as we learned the hard way with Vitamin E and beta-carotene supplements, what seems healthy may actually promote cancer growth. And then there is the unforgettable climax, Davis's epilogue. Much of it is a moving portrait of her mother's death from stomach cancer, which is one of the least treatable cancers. But then Davis tells a long story of her own toxic reaction to the stings of two dozen hornets, and it contains this:
All I know is that the day I almost died, I floated into the whitest, holiest, most comforting and shimmering radiance I have ever known. I came face to face with a beatific, white-robed, vaguely maternal, olive-skinned being. I gestured to my body on the table below and told her, "This is just lovely. Really wonderful. But, I'm not ready. I would like to get back."
I woke up.
The fact that Davis includes this hallucination in a purportedly serious book on cancer makes me wonder if she really did wake up. Call me old-fashioned, but when it comes to science, and to history, I like to stick to the facts, and nothing but the facts. The stakes are too high for anything else.
Ezekiel J. Emanuel is a breast oncologist and the chair of the department of bioethics at the National Institutes of Health. His book Healthcare Guaranteed: A Simple, Secure Solution for America will be published in June.
By Ezekiel J. Emanuel