The Cancer Chronicles (26 page)

Not long after my trip to Boston, I sat in on a presentation in which
Stand Up to Cancer described its vision of translational research and introduced some of its dream teams. The lecture room was packed and latecomers were turned away at the door. I found a place to stand in back and watched a slickly produced video in which
a young woman doing
cancer research at the University of North Carolina offered this slogan: “
Cancer isn’t getting smarter but we are.” At first that sounded wrong to me. Inside the body the cancer cells—competing, perhaps cooperating—are continually developing new talents. They evolve the ability to induce
angiogenesis and to resist apoptosis and the immune system—and everything else the body throws at them. And once treatment begins, they learn to circumvent the smartest drugs people can devise. No wonder the improvement in
survival rates has been so slow. But there is a limit to a cancer’s education. Ultimately either the cancer or the patient will die. Either way the evolutionary trajectory is halted. The next cancer must start from scratch.

But what if a cancer could break free? I thought of a recent issue of
Harper’s Magazine.
Prominent on the cover were the words “
Contagious Cancer” and a painting of a chimerical beast—part bird, part horse, part reptile, part human—dancing in a frenzy with a look of murder on its snaggle-toothed face. It was a painting by the surrealist
Max Ernst. It illustrated an article by
David Quammen, one of today’s best nature writers, and he focused on an affliction discovered in the mid-1990s on the island of Tasmania called devil facial tumor disease. It soon became clear that the lumps—each “
an ugly mass, rounded and bulging, like a huge boil”—were being transmitted from one
Tasmanian devil to another. This was not through viral infection. When the vicious creatures bit one another’s faces, tumor cells were passed along. This was a cancer that had evolved to where it could metastasize to another host. Through
genomic sequencing
scientists have since traced the origin of the cancer to a single female—“
the
immortal devil”—whose mutated
DNA can be found in all of the tumors.

Another contagious cancer in the animal kingdom is
canine transmissible venereal tumor. Again this is not spread by infection but by the direct exchange of cancer cells. In
hamsters a different sarcoma can be transferred by injection from one animal to another until the evolving tumor learns to make the jump on its own. It can also be
spread between hamsters by mosquitoes.

Quammen described three cases in humans—all medical professionals—in which cancer cells from a laboratory or hospital had become implanted in a wound. In one case, a young woman who poked herself with a syringe acquired colon cancer in her hand. A medical student died of metastatic cancer that began when he pricked himself after withdrawing liquid from a breast cancer patient. Those metastases ended with the recipient. But it is not impossible that a cancer might arise in the wild that has stumbled down an evolutionary pathway that ultimately allows it to leap from person to person. For a cancer like that, its education wouldn’t end. It would continue to evolve as it spread across the land. Increment by increment, it would get smarter.

On a clear winter day I drove the winding road up to the crest of
Sandia Mountain, which looms 10,678 feet over Albuquerque, to spend time basking in the emanations of the
Steel Forest, a thick stand of blinking broadcast and
microwave antennas that serves as a communications hub for New Mexico and the Southwest. Microwaves are a weak form of
electromagnetic radiation that sits in the lower half of the spectrum just above radio broadcast waves and below heat waves and the colors of light. Because of the compact size of the waves—half an inch to a foot across—they are easily focused into beams by dish antennas and used to relay television broadcasts, long-distance telephone calls, and other information from tower to tower and to satellites orbiting in the sky.

Microwaves are also transmitted and received by
cellular telephones and
wireless Internet equipment, and
Santa Fe had recently become a nexus for people who believe these emissions cause brain tumors and other sickness. They testified at hearings trying to keep wireless out of the public library and city hall. They opposed every new permit for a cell phone mast—even small ones in church steeples that no one could see. They would know they were there because of
their emanations. Or so they believed. One Santa Fean sued his next- door neighbor for remotely poisoning him with her iPhone, and a Los Alamos physicist is sometimes seen in public wearing a chain mail hood for protection. Knowing I was skeptical that the small doses of microwaves the public receives could possibly be harmful, he laid down a challenge. Go to the mountain, he said, and spend an hour or two by the antennas. “
See if aspirin cures the headache you’ll probably get, and see if you can sleep that night without medication.”

After I reached the top, I walked around and admired the endless views, browsed through the gift shop, watched a small outdoor wedding ceremony. I sat for long stretches and read
a book about mass hysteria and health scares. The cell phone fears seemed like a prime example, a case of metastatic memes—hard, impenetrable kernels of folk science passed from mind to mind with little deliberation. All the while I had in hand a microwave meter I’d purchased to make sure I was getting a dosage of at least 1 milliwatt per square centimeter. That is
the threshold set by the
Federal Communications Commission for what it considers safe exposure over a thirty-minute interval. (The sun shines upon us at
about 100 milliwatts per square centimeter.) Anti-wireless advocates consider the FCC standard far too high, many times greater than what the brain can bear. After two hours, I drove home and woke up the next morning feeling fine. It might be decades of course before I would know if I had seeded a brain tumor.

If so it would be through a means unknown to science. It is only when you reach the top of the spectrum—the highest frequencies of ultraviolet
light, followed by
x-rays and
gamma rays—that
radiation is
proven to be carcinogenic. The higher the frequency, the higher the energy—and the smaller and more cutting the waves. Measured in billionths and trillionths of a meter, these are the rays that can zip through cells, tearing electrons from atoms and damaging DNA. Blunter radiation like microwaves can only cause harm by vibrating and heating tissue—that is how a microwave oven boils water and cooks meat. But cell phone and wireless Internet emissions
are too feeble for even that. If they were causing cancer, it would have to be in more subtle ways.
Electromagnetic fields, microwaves included, can influence the motion of charged particles. And in a living organism streams of charged ions—calcium, potassium, sodium, chloride—flow in and out of cells. So maybe rippling these currents at a particular rhythm somehow elicits malignant behavior, interfering with a crucial
cellular pathway by amplifying or squelching it. The oscillations might conceivably suppress the immune system or have epigenetic influences—activating
methylation or some other chemical reaction that can affect the output of genes without directly mutating the DNA.

But all of that is speculation. There is no end to laboratory
research investigating how the waves might affect
mitosis, the expression of DNA, and other cellular functions or alter the efficiency of the blood-brain barrier or enhance known carcinogens. The results are
contradictory and inconclusive. One study showed that
glucose metabolism, the normal process by which cells turn sugar into energy, was higher in parts of the brain near where a cell phone antenna was held. Whatever clinical significance that might have is unknown, and the study was quickly contradicted by one finding that glucose activity was suppressed. A few studies—the outliers—have hinted that chronic microwave exposure might raise the risk of tumors in laboratory animals. But the experiments are far outnumbered by those finding no effect.

A review by the
World Health Organization of approximately 25,000 papers uncovered no convincing evidence that microwaves cause cancer. This is reflected in the epidemiology. For the last twenty years, while cell phone use has steadily increased, the annual age-adjusted
incidence of malignant brain tumors
has remained extremely low—6.1 cases per 100,000 people, or 0.006 percent—and for the last decade has been
slightly but steadily decreasing. That has not kept epidemiologists from investigating whether cell phones might still be having a tiny impact.
The most ambitious of these efforts,
Interphone, gathered information from five thousand brain
tumor patients in thirteen countries and compared it with a control group.
No relationship was found between the amount of time talking on a cell phone and the incidence of
gliomas,
meningiomas, and
acoustic neuromas—tumors that occur in areas of the head likely to get the most exposure from mobile phones. There actually was a slightly negative correlation: Regular users appeared to have a lower risk of getting brain tumors than people who didn’t use cell phones at all. Rejecting the likelihood of a protective effect, the authors of the final report interpreted the result as a fluke caused by unreliable data, sampling bias, random error—some flaw in methodology. The counterintuitive result also suggested that if there is some effect it is so minuscule that it is swamped by statistical noise.

Interphone was a
retrospective study, relying on memory, like the research that had led scientists to believe for a while that eating fruits and vegetables could drastically reduce the incidence of cancer. There was another reason, however, that has kept the results from being accepted as the final word. The study found no sign of a dose-response relationship, where cancer risk would rise steadily according to the number of hours spent on the phone. But for the 10 percent of people who reported the very highest use, the increased risk of glioma appeared to jump abruptly from 0 to 40 percent. A person’s
odds of being diagnosed with the cancer, the most common of all brain tumors, is about 0.0057 percent. A 40 percent increase would make that 0.008 percent. There was a similar but smaller spike for the other tumors. These were also interpreted by the authors as the result of a methodological flaw. Some subjects reported outlandishly long times spent talking on cell phones—as much as twelve hours a day—and that may have skewed the results.

Maybe people with brain cancer, desperate for an explanation, were overestimating the severity of their cell phone habit. Maybe their memory or their reason was impaired by the tumor. In any case,
a later study by the
National Cancer Institute looked at gliomas and found no sign that they have been increasing as cell phones have become a ubiquitous part of life. Many epidemiologists were
surprised when the
International Agency for Research on
Cancer decided that there was still enough uncertainty
to add microwaves to the long list of possible carcinogens—nowhere near being proven but worth keeping an eye on.

More answers might come from a prospective study that is almost as ambitious as the EPIC project on nutrition and cancer.
COSMOS (the
Cohort Study of Mobile Phone Use and Health) is monitoring 250,000 volunteer cell phone users for twenty to thirty years, which surely is time enough to find delayed effects. But even when it is completed decades later not everyone will consider the matter resolved. It still can’t be said flat out that
electrical power lines don’t slightly increase the risk of childhood
leukemia—a hypothesis that was
suggested to widespread disbelief more than three decades ago. The emanations from power lines are many times weaker than even microwaves. Their wavelength is enormous. While the microwaves people have been worrying about are measured in inches and radio broadcast waves in feet—hundreds of feet for the lowest-frequency AM stations—60 hertz power line waves are more than 3,000 miles wide. As they gently roll through neighborhoods they can induce faint currents in whatever they cross, including human cells. No means have been discovered for how that might cause cancer. Over the years most epidemiological studies have turned up no evidence of a danger. But there are always a few anomalies suggesting otherwise.

Sometimes it feels like we’re chasing our tails, obsessed with finding causes where there may be none.
Robert Weinberg once estimated that every second 4 million of the cells in our body are dividing, copying their DNA. With every division there are imperfections. That is the nature of living in a universe dominated by entropy—the natural tendency for order to give way to disorder. If we lived long enough, Weinberg observes,
we all would eventually get cancer. That doesn’t mean that we can’t reduce the
odds, even if only modestly, that we will get cancer before something else kills us. But
genetic errors are inevitable and necessary for us to evolve. Evolution is by random variation and selection, and mutations are the grist for the mill. Along the way cells have evolved the ability to identify and
repair broken DNA, but if the mechanism was foolproof evolution would stop. The trade-off is probably a threshold amount of
cancer.

Robert Austin, a biophysicist at Princeton University, goes so far as to argue that
cancer is here “on purpose”—that it is a natural response by which organisms deal with stress. When
bacteria are deprived of nutrients, they start replicating and mutating like mad—as though trying to evolve new survival skills. If the source of stress is an antibiotic, the winning adaptation might be one that produces an antidote to the poison—or quickens the pace at which the bacteria can flee. Maybe, Austin proposes, the cells in an
organism do the same thing. Backed into a corner they try to mutate their way out of trouble, even if it endangers the rest of the body. The best response might not be to fight back with chemotherapy and radiation, increasing the stress, but to somehow maintain the exuberant cells—the tumor—in a quiescent state, something that can be lived with.

Austin is one of dozens of scientists who have received money from the
National Cancer Institute as part of
an attempt to break the stalemate in the
War on Cancer by importing ideas from outside the usual channels.
Franziska Michor, the
evolutionary biologist I met in Boston, is also part of the endeavor. In other laboratories, physicists and engineers are bringing their own perspective by
studying the mechanical forces involved when cancer cells grow and divide and then migrate through the blood. Instead of speaking the language of biochemistry they use terms like “elasticity,” “translational and angular velocity,” “shear stress”—as if describing boats leaving dock to navigate down a river. Mathematicians are looking at cells at
a different level of abstraction—as communications devices—and using the same ideas from information theory that might be applied in the analysis of radio signals or telephone transmission lines. Perhaps
cells can be thought of as oscillators like tuning forks. Malignant
ones might be identified by their discordant harmonics—their own special ring. If so there might be a way to retune them. A chemist at Rice University is trying to use
radio frequency waves to kill cancer cells. First the cells would be injected with gold or carbon nanoparticles. Then the radio waves would cause them to vibrate, producing enough heat to destroy the cell from inside.