Almost every day, the media reports some alleged breakthrough stemming from research on cancer, leading many people to believe that science is winning the war against this dread disease. In this column, I’d like to offer an alternative—albeit grim–point of view.
President Richard Nixon declared war on cancer in 1971 and vowed that the disease would be cured within five years. Since then, the National Cancer Institute has spent more than $100 billion on research, and other institutions—private, public and non-profit–have spent many billions more.
All this spending, Gina Kolata of The New York Times suggested in a 2009 article, “Advances Elusive in the Drive to Cure Cancer,” has had a disappointingly small payoff. Kolata asserted that “the grim facts about cancer can be lost among the positive messages from the news media, advocacy groups and medical centers, and even labels on foods and supplements, hinting that they can fight or prevent cancer.”
Kolata acknowledged some genuine advances, noting that “a few rare cancers, like chronic myeloid leukemia, can be controlled for years with new drugs. Cancer treatments today tend to be less harsh. Surgery is less disfiguring, chemotherapy less disabling.”
But the overall death rate for cancer—adjusted for the aging of the U.S. population—has fallen by only five percent since 1950, Kolata pointed out. During this same period, the death rate for heart disease plummeted 64 percent and for flu and pneumonia 58 percent.
The decline in the cancer mortality rate since 1950 has not been steady. The rate actually increased from 1950 through the early 1990s and then began dropping. In other words, the mortality rate rose for two decades after Nixon’s declaration of war before dipping downward.
The decline in mortality rates since the early 1990s has been credited to improved tests and treatments, but Kolata tossed cold water on these claims last year. “The much touted recent drops in some cancer rates,” she writes, “were mostly attributable not to cancer breakthroughs but to a decline in smoking that began decades ago–propelled, in part, by federal antismoking campaigns that began in the 1960s.”
This view is corroborated by a 2010 Skeptical Inquirer article, “The War on Cancer: A Progress Report for Skeptics.” Reynold Spector, professor of medicine at Robert Wood Johnson Medical School, documented how a rise and fall in smoking preceded the rise and fall of the death rate from cancer, and particularly lung cancer.
Cancer-research boosters often state that people are surviving cancer for longer periods. But that is because men and women are being screened more frequently with higher-resolution tests and hence being diagnosed with cancer at earlier stages. They are living longer after diagnosis, not living longer in absolute terms.
As Spector explains in Skeptical Inquirer: “First, if one discovers a malignant tumor very early and starts therapy immediately, even if the therapy is worthless, it will appear that the patient lives longer than a second patient (with an identical tumor) treated with another worthless drug if the cancer in the second patient was detected later.”
Indeed, there is an emerging scientific consensus that mammography, the PSA (prostate-specific antigen) blood test and other screening methods have been overprescribed—and often lead to unnecessary treatment.
Men diagnosed with prostate cancer because of a PSA test are 47 times more likely to get unnecessary, harmful treatments—biopsies, surgery, radiation, chemotherapy—than they are to have their lives extended, according to one recent study. Another found that as many as 33 women diagnosed with breast cancer after receiving mammograms receive unnecessary treatment for every woman whose life is saved.
Last year, a group of oncologists acknowledged that Americans are being over-tested and over-treated for cancer. “Over the past 30 years,” the group stated, “awareness and screening have led to an emphasis on early diagnosis of cancer. Although the goals of these efforts were to reduce the rate of late-stage disease and decrease cancer mortality, secular trends and clinical trials suggest that these goals have not been met; national data demonstrate significant increases in early-stage disease, without a proportional decline in later-stage disease.”
Cancer has killed people I love at an early age, so I am as desperate as anyone for progress. Sometimes I feel like a jerk when I tell people how little progress we’ve made, especially after they tell me stories about loved ones who have triumphed over cancer. But if we are to have any chance of overcoming this terrible disease, we must face it squarely.
John Horgan directs the Center for Science Writings, which is part of the College of Arts & Letters. This column is adapted from one originally published in his ScientificAmerican.com blog, “Cross-check.”
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