Is high spending on cancer care `worth it`?
New York: With the United States spending more on healthcare than any other country — $2.5 trillion, or just over $8,000 per capita, in 2009 — the question has long been, is it worth it? At least for spending on cancer, a controversial new study answers with an emphatic "yes."
Cancer patients in the United States who were diagnosed from 1995 to 1999 lived an average 11.1 years after that, compared with 9.3 years for those in 10 countries in Europe, researchers led by health economist Tomas Philipson of the University of Chicago reported in an analysis published Monday in the journal Health Affairs.
Those extra years came at a price. By 1999 (the last year the researchers analyzed), the United States was spending an average of $70,000 per cancer case (up 49 percent since 1983), compared with $44,000 in Europe (up 16 percent). Using standard figures for an extra year of life, the researchers concluded that the value of the US survival gains outweighed the cost by an average $61,000 per case. The greater spending on cancer care in the United States, they conclude, is therefore "worth it."
Experts shown an advance copy of the paper argued that the tricky statistics of cancer outcomes tripped up the authors.
"This study is pure folly," said biostatistician Dr. Don Berry of MD Anderson Cancer Centre in Houston. "It`s completely misguided and it`s dangerous. Not only are the authors` analyses flawed but their conclusions are also wrong."
`BEST HEALTHCARE SYSTEM IN THE WORLD`
The question of how US healthcare compares with healthcare systems in other wealthy countries has become highly politicized. The 2007 film "Sicko" by activist Michael Moore compared US healthcare unfavourably with systems in Cuba, France and elsewhere. US House of Representatives Speaker John Boehner regularly claimed America has "the best healthcare system in the world."
Philipson is a fellow at the conservative American Enterprise Institute and at the Manhattan Institute, served in the administration of President George W. Bush and was a healthcare adviser to Sen. John McCain`s 2008 presidential campaign.
For the new analysis, Philipson and his colleagues analyzed the survival of cancer patients diagnosed from 1983 to 1999 with any of 13 common cancers, including breast, prostate, colorectal, and leukaemia.
Survival means how long a patient lived after being diagnosed. Philipson`s team focused in particular on survival gains; that is, how long did patients diagnosed in later years live compared with those diagnosed earlier in the period? Such gains, they argued, show what progress countries made in treating cancer.
While that may seem straightforward, survival data is among the most problematic cancer statistics, Philipson`s team acknowledges. In particular, they are plagued by something called lead-time bias.
If a tumour is diagnosed very early in its existence - if it has a long "lead time" - the patient may survive, say, two years if the tumour is very aggressive. If an identical tumour is found in that patient`s identical twin later, the twin will survive, say, six months. But the twins die at the same age. The first survived longer with cancer due to lead-time bias, but did not have a longer lifetime.
Crediting medical care with "improving survival" is therefore misleading, cancer experts have long argued. Lead-time bias makes it seem patients live longer, but the only thing that is longer is the number of years they know they have cancer, not their lifespan.
The authors of the "worth it?" study nevertheless base their analysis on survival data. They argue that because US cancer mortality rates fell faster than those in Europe, the survival gains must be real and not an artefact of lead-time bias.
Others call that approach fatally flawed. "Lead-time bias is an issue," said MD Anderson`s Berry. "I can see no hint of logic in their statement that `lead-time bias did not confound our results.`"
DIFFERENCES IN SCREENING IN US AND EUROPE
Even more problematic, said Berry, is a problem cancer experts have only recently recognized: over diagnosis. Because cancer screening is much more widespread in the United States than in Europe, especially for breast and prostate cancer, "we find many more cancers than are found in Europe," he said. "These are cancers that tend to be slowly growing and many would never kill anyone."
Screening therefore turns thousands of healthy people into cancer patients, even though their tumour would never threaten their health or life. Counting these cases, of which there are more in the United States than Europe, artificially inflates survival time, experts said.
"As long as your calculation is based on survival gains, it is fundamentally misleading," said Dr. H. Gilbert Welch, a healthcare expert at the Dartmouth Institute for Health Policy & Clinical Practice.
In the new analysis, the survival gains in the United States compared with Europe were greatest for prostate cancer, at more than triple the gains for breast cancer, the cancer with the second-greatest US survival edge. "These are the two cancers where screening has raised the most serious issues about lead-time bias and overdiagnosis," said Welch.
For melanoma and colorectal and uterine cancer, survival gains over the period analyzed were greater in Europe than the United States.
The Philipson team acknowledges that survival data can be misleading. They justify their approach, however, by saying that because deaths from cancer as a percentage of a country`s population fell faster in the United States than in 10 countries in Europe from 1982 to 2005, the higher US survival "suggests that lead-time bias did not confound our results."
Some experts in cancer statistics were not convinced.
"Why do the authors use the wrong metric - survival - in the analysis and then argue that the right measure - mortality - provides corroborating evidence?" asked Welch. "As long as your calculation is based on survival gains, it is fundamentally misleading."
Other calculations cast doubt on the superiority of US cancer care. For instance, breast cancer mortality fell 36 percent in the United Kingdom from 1990 to 2006, calculates MD Anderson`s Berry, and fell 30 percent among whites in the United States. (The US figure would be even lower, he said, if it included African-Americans, who generally have less access to health care.)
Cancer mortality in the United States is higher than in 11 countries reporting to the Organization for Economic Co-operation and Development, and lower than the rate in 14. Mortality is lower in Switzerland, Sweden, Japan and Finland, among others, but higher in Hungary, Slovenia, France and Britain, in the latest years for which OECD has data.
The reduction in cancer mortality in the United States since 2000 also puts it toward the middle of OECD countries. It is less than in Israel, Japan, Switzerland and some others, for instance, but better than in Britain, Estonia and Poland.
THE VALUE OF MORE SPENDING
The researchers acknowledge that it is not possible to conclude that improved survival comes from higher spending on cancer care. It might also come from more widespread cancer screening which, experts say, detects more and more "pseudo-disease" — that is, a tumour so non-aggressive it would never have threatened the person`s health or life. That alone would make the survival data look better.
The Philipson paper was supported in part by Bristol-Myers Squibb Co, whose cancer drugs include Yervoy. A drug for advanced melanoma, it costs $120,000 for a full course of treatment. Clinical trials showed that Yervoy produces a near-miraculous cure for some patients, with a median increase in survival of 3.6 months.
US spending on cancer care has continued to increase, reaching $72 billion in 2004, the last year for which data is available.
The new study did not examine the cost-effectiveness of that care. "In the last decade, spending in the US has increased more than in Europe," said Philipson. "I would be extremely surprised if the survival gains haven`t continued. But it is a much more open question whether that additional spending has been accompanied by an increase in longevity."
In the last decade, a number of very expensive cancer drugs were introduced into the United States, including Dendreon Corp`s Provenge for prostate cancer ($93,000 per treatment) and Bristol and Eli Lilly and Co`s Erbitux ($100,000 per year). Their analysis, say Philipson`s team, "does not imply that all treatments are cost-effective."
Worse, many are not medically effective. Last week, the American Society of Clinical Oncology released a list of five cancer tests and therapies that do not help patients live longer or suffer less — even apart from how much they cost.
VALUING OF A YEAR OF LIFE
Healthcare economists focused on a different aspect of the new study, namely, how much each additional year of life is worth. Philipson`s team assumes a value of $150,000 to $360,000.
"Are American taxpayers willing to pay $150,000 in added taxes to purchase an added life year for some poor person?" asked health economist Uwe Reinhardt of Princeton University. "Does the urge to cut government spending on Medicare and Medicaid suggest Congress is willing to purchase added life years for anyone who cannot purchase it with his or her own money at a price of $150,000 per year?"
Other studies in the journal raise questions about the value of some aspects of cancer care. One finds that the use of a prostate-cancer treatment called "intensity modulated radiation therapy" has soared since 2001, including for men with low-risk forms of the disease. Since IMRT costs $15,000 to $20,000 more than other therapies despite a lack of evidence that it improves outcomes, that raises "concerns about over treatment, as well as considerable health care costs," write University of Michigan researchers.
Another study finds that urologists who perform biopsies themselves, rather than refer patients to another physician, are more likely to perform prostate biopsies on men who are unlikely to have prostate cancer. "These findings suggest that doctors` own financial interests are driving decisions to perform biopsies which are of little to no benefit to patients," Health Affairs said in a statement.