The U.S. spends far more on cancer care than 10 European countries, but according to a new study, it may be “worth it” as “the value of the survival gains greatly outweighed the costs.”

The study, published this week in Health Affairs, found that U.S. spending on cancer care, in 2010 dollars, increased by 49% from 1983 through 1999, from $47,000 per cancer case to $70,000 per case. Meanwhile, in the European countries, spending on cancer care (also in 2010 US dollars) increased 16% from $38,000 per cancer case to $44,000. But the sharp increase in cost seems to come with clear benefits; for patients diagnosed with cancer between 1995 and 1999, average survival from time of diagnosis in the U.S. was 11.1 years, while in Europe it was 9.3 years. These gains were greatest in patients with prostate and breast cancer, as well as chronic and acute myeloid leukemia.

At first glance, this study, which was partially funded by cancer-drug maker Bristol-Myers Squibb, should give ammunition to those stalwarts who continue to insist that America’s health care is the very best that money can buy—at least when it comes to cancer. But despite the findings that the “value of survival” far outweighs the skyrocketing financial costs of cancer care (the National Cancer Institute puts it at $125 billion in 2010)—many questions remain.

First of all, the Health Affairs authors do note some limitations of the study; for example, even though the results suggest that survival gains for U.S. cancer patients have been “worth it” in terms of cost, “this does not imply that all treatments are cost-effective. Additionally, we could not examine the extent to which better outcomes were the result of earlier diagnosis due to screening or newer treatments,” they write. I would add, the data analyzed are more than a decade old—cancer treatments and diagnostic technologies have changed both in cost and efficacy since then. How do we factor in the “value” of a brand new $90,000 cancer drug that keeps a small percentage of very sick patients alive for at most two or three more months?

There are other problems with reading too much into this report.

Here’s something interesting I found in the study: “US mortality rates for cancer are lower than those in Europe, despite higher rates of cancer incidence in the United States.” My first question was why do we have higher rates of cancer incidence in this country? Is it our diet, exposure to pollutants, smoking rates or other environmental or even genetic determinants? None of these seems likely (especially the smoking bit), but there is one major difference. We do a lot more cancer screening in the U.S. than in Europe and this can be a double-edged sword.

While it is true that screening tests like mammography and PSA testing can catch cancers at an earlier, more treatable stage, early diagnosis can also lead to seemingly longer survival times. The researchers explain that they avoided so-called lead-time bias—meaning a person appears to survive longer if they are diagnosed 6 months before another—by comparing changes in mortality rates overall. “By analyzing population mortality rates, which are insensitive to lead-time bias, we show that US cancer mortality rates fell faster than cancer mortality rates in the European Union. This must be due to real improvements in cancer survival.”

But lead-time bias isn’t the only factor that can skew survival data and the authors leave out a very important factor: In the U.S. where preventive screening is used far more frequently than in Europe, there is also a documented rise in over-diagnosis of cancer. A recent study in the Annals of Internal Medicine  found that over-diagnosis accounted for 15% to 25% of breast cancer cases identified by a large screening program. For example, a woman who is diagnosed with a tiny growth in her breast that is unlikely ever to progress (a so-called pseudo-cancer), or progresses so slowly that she will die of something else, would be counted as one who has been “cured” of cancer through early diagnosis and better treatment in the Health Affairs study. She will have undergone surgery, radiation, and perhaps chemotherapy that cost tens of thousands of dollars—treatment that likely caused physical and psychological harm, but in the end added no “value” in terms of extra life-years.

The same is true for prostate cancer, where some 70% of men diagnosed with a prostate-specific antigen (PSA) test have a low-risk form of the disease. According to a report in the journal Oncology, “over 90% of these men will be treated for their disease at diagnosis although it is estimated that up to 60% of men may not require therapy, even over the long term.” The report adds that a recent cost-effectiveness analysis of PSA screening estimated that the cost of diagnosis and treatment is over $5,227,306 per patient to prevent one death from prostate cancer.

The Health Affairs authors, led by Tomas Philipson, professor of public policy at the University of Chicago and senior economic adviser for the FDA and CMS during the second Bush presidency, do not consider that survival rates might be inflated partially due to this considerable problem of over-diagnosis in the U.S., a country far more enamored with screening mammography and PSA testing than their counterparts in Europe. Instead they find the opposite; “Finally, earlier detection and management associated with increased screening for breast cancer through mammography, and for prostate cancer through prostate-specific antigen testing, in the United States relative to Europe also could have been responsible for improved US patient outcomes.”

There is one more important question about cancer treatment and survival that was not addressed in the Philipson, et. al. study: If you include the pain, suffering and loss of quality of life some cancer patients experience during those extra months of survival, is the cost of care still “worth it?”

To help answer this, I urge you to read a companion story in Health Affairs by Amy Berman, a 51-year-old registered nurse and senior program officer at the John A. Hartford Foundation who was diagnosed with incurable inflammatory breast cancer and has chosen to take a palliative approach to treatment of her disease. She writes;

“Is there a downside to aggressive treatment? You bet. In the case of incurable cancer, it can mean rounds of radiation or chemotherapy, or both, with side effects of crushing fatigue, overwhelming nausea, burned and peeling skin, permanent pain or numbness of fingers and toes, and the cognitive impairment known commonly as “chemo brain.” The ‘treat aggressively’ approach can leave patients bruised and battered, wishing they were dead.”

She adds, “Yes, perhaps, a few months of added life come with it—but at what cost?”

Finally, doctors who treat cancer patients note another, less corporeal “toxic” effect of high-cost cancer treatment in America. Two oncologists from the Duke Cancer Institute wrote in Kaiser Health News last August; “We know that the experience of receiving cancer treatment can result in a physical toxicity, but recent data suggest that cancer treatment might also cause financial toxicity that affects the daily lives of patients and their families.” The Duke doctors cited a study they conducted where they found that although 99% of the mostly older cancer patients were insured (83% with prescription drug benefits), they still paid an average of more than $700 a month for their cancer care out of pocket. Most reported going through their life savings to foot the bill; 11% described cancer care as a catastrophic financial burden.

This begs the question of why are we Americans paying so very much for our cancer care? We won’t really know if it’s “worth it” until we find out which factors are actually responsible for the survival gains over our European counterparts seen in cancer treatment—is it earlier detection? Better chemotherapy drugs? More targeted therapies? Surgical advances? Or are some of our gains really due to over-diagnosis or unwanted treatments that may boost survival a couple of months but destroy a patient’s quality of life?

Naomi Freundlich is a journalist, policy expert and health advocate who blogs at Reforming Health.

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