The Cancer Chase

By Mark Collins



PITT GRAD DEVRA LEE DAVIS PURSUES SOME UNSETTLING STATISTICS.

STREAMS ARE HARD TO DIVERT, and so are cliches. The word "mainstream" is a cliche for "following the common wisdom." For Devra Lee Davis, becoming "mainstream" is an act that's, well, fluid.

But Davis (Arts and Sciences '67), a senior scientific advisor for Health and Human Services (HHS) in the Clinton administration, didn't so much move toward the mainstream as she waited for the mainstream to catch up with her. For more than a decade Davis' epidemiclogical research showed that many types of cancer were increasing in people over 45§this despite billions spent on research and treatment. Her research showed increases even stream as she waited for the mainstream to catch up with her. For more than a decade Davis' epidemiclogical research showed that many types of cancer were increasing in people over 45§this despite billions spent on research and treatment. Her research showed increases even when the usual suspects§ smoking, drinking, and aging§were eliminated as causes. It was a finding that was bound to raise the hackles of those who wanted to believe that we've been winning the current "war against cancer." For years, some in the cancer establishment resisted Davis' conclusions. Today, however, these conclusions§ that there must be other factors besides smoking, drinking, and aging that account for these increases§have gained wide acceptance.

Davis says that great strides have been made in reducing cancers in those under 45. But this group accounts for

only five percent of cancer deaths. With the exception of lung and stomach cancer, most forms of cancer are increasing

in older adults. "These changes are so great and rapid," she wrote in the British medical journal The Lancet in 1990, "that it would be imprudent not to investigate their causes aggressively." Her conclusion about growing cancer rates wasn't the first warning bell ever heard, but probably the loudest. What Davis implies with her findings is that if our decades of fighting

cancer have largely failed, and if the causes seem to be environmental, then a new direction is needed§one that emphasizes cancer prevention as well as treatment, and emphasizes the search for causes as well as cures. If the increases can't be explained solely by smoking, drinking, and aging, there must be another culprit, perhaps something we're breathing, or a chemical we're working with.

For example, breast cancer is rising in women over 55§"women who by and large are not drinkers, women who hadtheir children early in life, both of which should yield lower cancer rates," Davis says. As a possible explanation, she has begun exploring the connection between cancer and two kinds of environmental factors. The first are chlorinated organic

compounds such as atrazine, a common pesticide, and derivatives of DDT, a substance long banned but which persists in the ecosystem. The second is a group known as aromatic hydrocarbons§gasoline and other petrochemicals. Could exposure to these chemicals contribute to the increase in breast cancer? "Women over 55 are the generation who began as 'Rosie the Riveter,' taking over many industrial jobs during the war, then became the women of 'The Feminine Mystique,' who used all these new cleaning chemicals to make their homes spotless," Davis says. "It's not to say that working in factories or with

household chemicals have caused cancer; it's to say that there's an increase in breast cancer that needs to be explained.

Better detection and screening methods account for some of the increase in breast cancer cases, but it would be foolish to assume that they account for all of the increase." At her new position at HHS, Davis will get her chance to recommend and administer new research into cancer-causing agents and possible prevention.

Before her current job, Davis worked as resident scholar at the National Academy of Sciences, where she compiled most of her research. Davis' findings, says Samuel Broder, director of the National Cancer Institute, should keep anyone from becoming smug about the progress against cancer. "They teach us that there is both good news and bad news," says Broder. But, he adds, like patterns that she discovered in the States: With the exception of lung and stomach cancers, there's an increase in overall cancer for people over 45. "That was an exciting moment, to see the exact same pattern emerge," she says.

most people who tell it like it is, "she's frequently hit from both sides."

Indeed. While her work has since been acknowledged and accepted, Davis' research has had its share of the crisis inDonora and her father's own cancer battle. Davis herself is quick to chalk it up to coincidence; she's also quick to stop more questions with a polite wave of her hand. Talking about her father requires a short time-out to regain her composure. "At least I can't be accused of just looking at numbers," she says finally. "I understand that these statistics mean something, that there

critics. Throughout her career, Davis says, colleagues repeatedly pulled her aside to explain how it might seem that the billions spent of cancer research have failed to lower the cancer mortality for people over 45, but that this is not the case. Instead the increases are merely "artifacts"§anomalies that are the result of poor record-keeping or inaccurate diagnosis and not the result

of some new and lethal causes.

Davis examined the supposed artifacts of statistical increases in cancer§ namely better diagnostics and increasedincidence of listing "cancer" as the cause of death. But no artifacts were found. For instance, death certificates can record cancer in a specific site (say, pancreas), or cancer whose site of origin is unknown. If there's an increase in specific-site cancer due to better reporting methods and diagnostics, then one expects a decrease in reports of nonspecific cancers. But both types have increased. Again, colleagues "explained" that the increases were an aberration, that other industrial countries would

have their own unique trends. "The prevailing attitude," Davis recalls, "was, 'We know better. Trust us.'"

Davis didn't. In 1989, she packed up her then-nine-year-old daughter and traveled to Germany, England, and

Sweden to track cancer mortality and compare it with US rates. The comparison was meant to neutralize statistical

differences in cancer diagnosis and treatment among different countries§ factors that might cause deviations in cancer reporting. Yet in all three countries, Davis unearthed the same cancer patterns that she discovered in the States: With the exception of lung and stomach cancers, thereˆs an increase in overall cancer for people over 45. "That was an exciting moment, to see the exact same pattern emerge," she says. "Then you know something is going on. It refuted the 'trust us' argument."

But critics were not so easily quelled. In a profile of Davis in a 1991 New York Times Magazine, Sir Richard Doll, one of the world's most esteemed epidemiologists, debated the premise of Davis' work. While Doll conceded that cancer rates in older adults are increasing, he added, "The question is, Is it of any particular importance with respect to causes?" Besides, Doll said, these increases "have been a matter of scientific knowledge for a long time before Devra Davis drew attention to them." When asked whether Davis' research was wrong or simply unoriginal, Doll replied, "Both."

But over the past few years Davis' exhaustive research has withstood scrutiny, and other investigators have followed up on her work. Doll himself has changed his views and even published analyses indicating that there are unexplained increases in certain cancers.

EVER SENSITIVE TO FACTORS that might detract from her carefully culled statistics, Davis is reluctant to talk about the ironic connections between her personal life and her research. She was born in Donora, Pennsylvania, home of one of the worst air pollution disasters on record. In 1948, an air inversion kept the smoke from the nearby U.S. Steel plant trapped

over Donora for five days. Twenty people died, and Donora's morbidity and mortality rates remained higher than usual for more than a decade.

Davis was two at the time. Her father had worked at U.S. Steel as a machinist. Davis went to Pitt, then to the University of Chicago for her Ph.D. in science studies, followed by a master's in public health at Johns Hopkins. She

published her first findings on cancer mortality in 1978. A year later, her father was diagnosed with bone cancer.

He died in 1984. It's hard not to wonder whether some of Davis' work isn't motivated by the crisis in Donora and her fatherˆs own cancer battle. Davis herself is quick to chalk it up to coincidence; sheˆs also quick to stop more questions with a polite wave of her hand. Talking about her father requires a short time-out to regain her composure. "At least I canˆt be accused of just looking at numbers," she says finally. "I understand that these statistics mean something, that there are real people involved."

BECAUSE DAVIS NOW WORKS IN the Clinton administration, she's aware that some might mistakenly perceive political overtones to her role as advisor. But she is quick to point out that she also advised Bush. "Everyone has an interest in prevention," she says. "Fifteen percent of our gross domestic product goes to health care costs, $100 billion of that for costs relating to cancer. Even if we prevented one percent, that's a savings of one billion."

She's also calling for a redefinition of the government's role in disease prevention. In the past, she says, suchbureaucratic positions have been politicized, driven by a Big Brother belief in government regulation, or else by a hands-off policy that bordered on neglect. Davis seeks a balance. "There are some things so easy to do," she says. For instance, some studies suggest that reducing newborns' 24-hour exposure to unshielded, high-intensity fluorescent lights helps reduce the risk of certain childhood cancers. "So you recommend that hospital infant nurseries turn down their lights or turn them off when

the babies are sleeping," Davis says. "It's easy, and it saves energy. But many things aren't so easy. And I am not ready to give up the conveniences of modern life. I'm not ready to give up my car." Instead, she argues for more and better research of causes and prevention. "I think it's a matter of making more informed choices."

Information§perhaps that's the secret to persuading the "mainstream" to follow your course. Instead of shouts andwhistles and mad stamping of feet, you can carefully construct a new direction, one built on solid research and a repeated willingness to test the common wisdom, and eventually the crowd will follow.