9 Haziran 2012 Cumartesi

The fight against cancer and effectiveness of chemotherapy

Most people want to fend off death no matter the cost. More than $40 billion is spent worldwide each year on cancer drugs. In the United States, they constitute the second-largest category of pharmaceutical sales, after heart drugs, and are growing twice as fast as the rest of the market. The bulk of this spending goes to chemotherapy, which is used in a variety of ways and has proven effective on some cancers, including leukemia, lymphoma, Hodgkin’s disease, and testicular cancer, especially if these cancers are detected early. 

But in most other cases, chemotherapy is remarkably ineffective. An exhaustive analysis of cancer treatment in the United States and Australia showed that the five-year survival rate for all patients was about 63 percent but that chemotherapy contributed barely 2 percent to this result. There is a long list of cancers for which chemotherapy had zero discernible effect, including multiple myeloma, soft-tissue sarcoma, melanoma of the skin, and cancers of the pancreas, uterus, prostate, bladder, and kidney. Consider lung cancer, by far the most prevalent fatal cancer, killing more than 150,000 people a year in the United States. 

A typical chemotherapy regime for non-small-cell lung cancer costs more than $40,000 but helps extend a patient’s life by an average of just two months. Thomas J. Smith, a highly regarded oncology researcher and clinician at Virginia Commonwealth University, examined a promising new chemotherapy treatment for metastasized breast cancer and found that each additional year of healthy life gained from it costs $360,000—if such a gain could actually be had. Unfortunately, it couldn’t: the new treatment typically extended a patient’s life by less than two months. Costs like these put a tremendous strain on the entire health-care system. 

Smith points out that cancer patients make up 20 percent of Medicare cases but consume 40 percent of the Medicare drug budget. Some oncologists argue that the benefits of chemotherapy aren’t necessarily captured in the mortality data, and that while chemotherapy may not help nine out of ten patients, it may do wonders for the tenth. Still, considering its expense, its frequent lack of efficacy, and its toxicity—nearly 30 percent of the lung-cancer patients on one protocol stopped treatment rather than live with its brutal side effects—why is chemotherapy so widely administered? The profit motive is certainly a factor. 

Doctors are, after all, human beings who respond to incentives. Oncologists are among the highest-paid doctors, their salaries increasing faster than any other specialists’, and they typically derive more than half of their income from selling and administering chemotherapy drugs. Chemotherapy can also help oncologists inflate their survival-rate data. It may not seem all that valuable to give a late-stage victim of lung cancer an extra two months to live, but perhaps the patient was only expected to live four months anyway. On paper, this will look like an impressive feat: the doctor extended the patient’s remaining life by 50 percent. Tom Smith doesn’t discount either of these reasons, but he provides two more. It is tempting, he says, for oncologists to overstate—or perhaps over-believe in—the efficacy of chemotherapy. “If your slogan is ‘We’re winning the war on cancer,’ that gets you press and charitable donations and money from Congress,” he says. “If your slogan is ‘We’re still getting our butts kicked by cancer but not as bad as we used to,’ that’s a different sell. 

The reality is that for most people with solid tumors—brain, breast, prostate, lung—we aren’t getting our butts kicked as badly, but we haven’t made much progress.” There’s also the fact that oncologists are, once again, human beings who have to tell other human beings they are dying and that, sadly, there isn’t much to be done about it. “Doctors like me find it incredibly hard to tell people the very bad news,” Smith says, “and how ineffective our medicines sometimes are.” If this task is so hard for doctors, surely it must also be hard for the politicians and insurance executives who subsidize the widespread use of chemotherapy. 

Despite the mountain of negative evidence, chemotherapy seems to afford cancer patients their last, best hope to nurse what Smith calls “the deep and abiding desire not to be dead.” Still, it is easy to envision a point in the future, perhaps fifty years from now, when we collectively look back at the early twenty-first century’s cutting-edge cancer treatments and say: We were giving our patients what? The age-adjusted mortality rate for cancer is essentially unchanged over the past half-century, at about 200 deaths per 100,000 people. 

This is despite President Nixon’s declaration of a “war on cancer” more than thirty years ago, which led to a dramatic increase in funding and public awareness. Believe it or not, this flat mortality rate actually hides some good news. Over the same period, age-adjusted mortality from cardiovascular disease has plummeted, from nearly 600 people per 100,000 to well beneath 300. What does this mean? Many people who in previous generations would have died from heart disease are now living long enough to die from cancer instead.

Indeed, nearly 90 percent of newly diagnosed lung-cancer victims are fifty-five or older; the median age is seventy-one. The flat cancer death rate obscures another hopeful trend. For people twenty and younger, mortality has fallen by more than 50 percent, while people aged twenty to forty have seen a decline of 20 percent. These gains are real and heartening—all the more so because the incidence of cancer among those age groups has been increasing. (The reasons for this increase aren’t yet clear, but among the suspects are diet, behaviors, and environmental factors.)

3 Haziran 2012 Pazar

Ammonium nitrate

By 1850, worldwide population had grown to 1.3 billion; by 1900, 1.7 billion; by 1950, 2.6 billion. And then things really took off. Over the next fifty years, the population more than doubled, reaching well beyond 6 billion. If you had to pick a single silver bullet that allowed this surge, it would be ammonium nitrate, an astonishingly cheap and effective crop fertilizer. It wouldn’t be much of an overstatement to say that ammonium nitrate feeds the world. If it disappeared overnight, says the agricultural economist Will Masters, "most people’s diets would revert to heaps of cereal grains and root crops, with animal products and fruits only."

Food production per capita

In late eighteenth-century America, “it took 19 out of 20 workers to feed the country’s inhabitants and provide a surplus for export,” wrote the economist Milton Friedman. Two hundred years later, only 1 of 20 American workers was needed to feed a far larger population while also making the United States “the largest single exporter of food in the world.”

23 Mayıs 2012 Çarşamba

The beauty of terrorism

The beauty of terrorism—if you’re a terrorist—is that you can succeed even by failing. We perform this shoe routine thanks to a bumbling British national named Richard Reid, who, even though he couldn’t ignite his shoe bomb, exacted a huge price. Let’s say it takes an average of one minute to remove and replace your shoes in the airport security line. In the United States alone, this procedure happens roughly 560 million times per year. Five hundred and sixty million minutes equals more than 1,065 years—which, divided by 77.8 years (the average U.S. life expectancy at birth), yields a total of nearly 14 person-lives. So even though Richard Reid failed to kill a single person, he levied a tax that is the time equivalent of 14 lives per year.