Forty years into the "War on Cancer," casualties are mounting -- and we still don't know what motivates the enemy.
Please STOP the Race for the Cure and START the Race for the Cause
The Experimental Generation
In June 2010, a dermatologist cut a weird growth from my left wrist. The growth was wart-sized, grape-purple and stippled black. It was sensitive to the touch and bled when scratched.
Two weeks later, the doctor told me the tumor was malignant -- melanoma, the deadliest form of skin cancer.
The doctor also told me this:
You're part of an experimental generation.
She meant that in the past 30 years, she'd seen an alarming rise in skin cancer, and not just among older people. (I was 45.) Despite the advent of sunscreen and the fact that people don't go outside as much as they used to, she'd even been seeing more moles -- possible precursors to melanoma -- on children.
One or more risk factors for melanoma, she reasoned, must have changed. My doctor's guess: the human-caused depletion of atmospheric ozone, which allows more ultraviolet light -- a leading melanoma risk factor -- to reach our skins.
But other variables have also changed in recent decades, including the chemicals we're exposed to through air, water and food. How much might exposure to these be increasing the risk for melanoma and other forms of cancer?
Mostly, the answer is: We really don't know.
And that's the experiment, in which we've become the test subjects -- without our knowledge or consent.
Less Death, More Cancer
My doctor's language, inevitably, recalled Rachel Carson's Silent Spring. Writing in the years when America first went whole-hog for synthetic chemicals, Carson warned that we were subjecting humanity and nature to a vast, uncontrolled experiment.
In 1964, Carson herself died of cancer. And in a decade that saw rising cancer rates and death tolls, fear of the malady metastasized. On Dec. 23, 1971, President Nixon signed the National Cancer Act, pledging to make the "conquest of cancer a national crusade."
In the next several weeks, you'll likely see 40th-anniversary reports and pronouncements on how this epic initiative -- inevitably dubbed the "War on Cancer" -- is going. Most will gauge progress toward keeping cancer patients alive, or toward the "cancer cure" that Nixon sought. You'll likely hear disappointment that cancer remains uncured, countered with hopeful tidings of new gene-based therapies.
But here's a fact you probably won't hear much: You're actually more likely to get cancer than when the War on Cancer began.
In announcing his "conquest," Nixon noted that cancer struck one in four Americans. Four decades later -- and after hundreds of billions of dollars in research, radiation and chemotherapy -- the figure has risen to about two in five. Nearly half of all men, and more than a third of all women, will get cancer. That's about 1.6 million new diagnoses each year.
And for most major types of cancer, according to National Cancer Institute statistics, incidence remains higher than it was in the early '70s. While record-keeping in the early 1900s was less authoritative, cancer registries suggest incidence also rose steeply for most of the past century; by one estimate, it rose 85 percent between 1950 and 2001 alone.
Meanwhile, between 2003 and 2007, the incidence of liver cancer rose for men, along with thyroid cancer among women. Melanoma climbed for both genders; so did non-Hodgkin lymphoma, leukemia and cancers of the kidney and pancreas.
The news isn't all bad: Incidence of two major types of cancer, colorectal and cervical, have dropped steeply in recent decades, largely because of improved screening. And cancer now kills less surely. Death rates for the most common forms -- lung, breast, colorectal, prostate -- have fallen in the past 20 years.
Even so, 570,000 Americans die of cancer annually -- and the overall cancer death rate is only about 6 percent lower than it was in 1950. Our boat is still leaking; we're just bailing faster.
This trend of "less death" and "more cancer" is starkest among children. Forty years ago, a child with cancer faced a virtual death sentence. (I had a sister who died of neuroblastoma, in 1971, at age 5.) Today, most child cancer victims survive, and death rates keep dropping. But incidence keeps rising -- by about 0.6 percent annually over the past 20 years, mostly driven by leukemia. An estimated 7 million American kids under age 10 are now living with cancer.
Nor is there any easy explanation for dramatic rises in cancers that strike primarily young adults, like testicular cancer. While cancer incidence is dropping in people over age 65, probably because of smoking's long decline, it's rising in people under 50 … despite smoking's long decline.
Our Chemical Romance
Cancer itself is complicated; it's really more than 100 diseases, affecting numerous parts of the body and presenting a wide range of medical challenges. But broadly, cancer happens when cells in our body grow out of control.
Human bodies make cancer cells constantly, and as far as we know, they always have. (Clinical descriptions of cancer seemingly date to ancient Egypt.) Usually, our bodies kill them off. When such cells do thrive, the causes of the disease are sometimes readily identifiable: Lung cancer is largely attributable to smoking; a small number of cancers are caused by viruses (with liver cancer, for instance, linked to hepatitis B and C). Diet and sedentary lifestyles have been implicated in some cancer. Genetics play a role, though likely much less than most people think.
Meanwhile, ever since surgeon Percival Pott observed in 18th-century London that chimney sweeps were prone to cancers of the scrotum, we've also known that many environmental pollutants are carcinogens. Asbestos (still used in automobile brake pads) is one. So is benzene, a common pollutant in automobile and factory exhaust. Likewise formaldehyde, found in consumer products including some wooden furniture and recently designated a "known human carcinogen."
Industrial workers still often bear the brunt of the most severe exposures. The threat is also elevated for inhabitants of areas like Louisiana's "Cancer Alley," a stretch of the Mississippi River known for massive toxic releases from the petrochemical industry, and for exceptionally high cancer rates among its mostly poor, mostly black residents.
Yet the increase in cancer rates isn't confined to specific regions or occupations. Increasingly, researchers are interrogating the environment as a cause of cancer -- and suggesting that cleaning up the environment may help prevent it.
After all, the past century's rise in cancer has been paralleled by the rise in synthetic chemicals and other pollutants in everyday life. In the years following World War II, plastics took over for wood, metal and glass. And from 1950 through 1975, pesticide production -- Rachel Carson's key concern in Silent Spring -- grew sevenfold, to 1.4 billion pounds a year.
In 2008, according to an EPA inventory, there were some 84,000 synthetic chemicals on the market. (There are surely more today.) Most are made from coal, oil or natural gas. But only a handful of these substances have ever been tested for health effects. We're in contact with many of them on a daily basis. They're in diesel soot and they're in shampoo. They reach us through the packaging that contains our food, the pesticides on apples and the flame-retardant fabric woven into children's car seats.
Some of these chemicals accumulate in our bodies. Others are shed into the environment, where they may persist for decades.
A growing array of studies, for example, link cancers including breast, prostate, leukemia and multiple myeloma to pesticide exposure. I was personally intrigued that a 2007 study from Italy tied melanoma to household pesticide use.
Perhaps the most surprising survey was Reducing Environmental Cancer Risk: What We Can Do Now. The April 2010 report was issued by the President's Cancer Panel, chaired by two appointees of President George W. Bush. The widely publicized report cited "a growing body of evidence linking environmental exposures to cancer."
Wrong War, Wrong Race
Cancer patients, understandably, care less about why there's cancer than how to treat theirs. And as cancer victims go, I'm lucky; I quickly learned that mine hadn't spread. My only keepsakes so far are a couple of scars (including one for the lymphectomy).
I'm glad for that, and glad that there are ways to help people sicker than me. But in this four-part series, I'm less interested in the War on Cancer everyone will be talking about. It feels like the War on Terror, or the War on Drugs: a hugely expensive effort to fix a problem whose causes we're ignoring.
What I want to know is, why are we getting sick? Why has melanoma incidence tripled since the 1970s? Why is thyroid cancer rising even faster? Why are men younger than me increasingly getting tumors in their testes? Why are babies getting more cancer?
And in a country where you can't swing a surgically excised lymph node without hitting someone's Race for the Cure, why does no one ever hold a Race for the Cause?
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