Saturday, March 27, 2010

Fuzzy thinking apparently continues in Barcelona

Maria Cheng continues to report on the Barcelona breast cancer conference today: and the topic du jour is the effectiveness of breast cancer screening. In an article practically devoid of anything substantiating, the experts would seem to be arguing that 1) Too many women are being screened for breast cancer, 2) Too much screening is bad because of "false alarms and unneeded biopsies", 3) It really doesn't help the women being screened all that much, and 4) Patients need to be screened prior to being screened for breast cancer. Interestingly enough, there is no discussion reported as how this screening of the screenees would be done. Also absent is any substantiation of the statement that screening doesn't really help that much. I think I need the words "help" and "much" defined a little better here.

There is a statement in the article:

U.S. researchers last year estimated five lives saved per thousand women screened.

If your mother, wife, or daughter were one of the five, would you consider breast cancer screening "not much help"? There are roughly 60 million women in the US over the age of 40. If only 20% of them were being screened, this would be 60,000 lives saved. How in the name of God does this get called "not helping very much"?

But the telling statement comes towards the end of the article:

Jorgensen (Karsten Jorgensen of the Nordic Cochrane Centre in Copenhagen) said screening has become more of a political issue than a medical one. Officials have spent so many years convincing women to get mammograms that it will be difficult to now change policies, especially with a very vocal and powerful breast cancer lobby.

Political? Policies? Obviously, we are several steps away from a doctor advising his female patients, based on their lifestyle, family history, etc. whether they should have a mammogram when they turn 40. This is about money, plain and simple. Health care costs, among other entitlement programs, are driving the European economy into bankruptcy and the medical community meeting in Barcelona is trying to rationalize cutting costs.

In fairness, I am drawing conclusions based on Ms. Cheng's reporting of the Barcelona conference and obviously there is a lot more discussion and information being distributed that I don't have access to. If I am maligning the intent of the conferees, I apologize but will still hold Ms. Cheng to task for bad reporting.

In the interest of full disclosure, my mother died of ovarian cancer and my mother-in-law died of breast cancer. Do I want my wife and daughters to be screened? Absolutely. Would I pay for it myself? Without question. If medicine ever came to a point where they would be denied screening based on a bureaucrat's view as to what was an "acceptable" cost, what can I say? Aux barricades, chers concitoyens

Friday, March 26, 2010

Breast cancer, diet, and exercise...I smell a rat

"Up to a third of breast cancer cases in Western countries could be avoided if women ate less and exercised more..." -- Associated Press

When stories like this show up on the front page of the paper, they always get my attention. I'm naturally a skeptic and am always suspicious when technical subjects get sensationalized. Normally, when I read something like this, I suspect statistical douchery. For example, suppose you search a database and find that the breast cancer mortality rate for women who don't exercise is 27 deaths per 100,000 and the mortality rate for women who exercise is 18 deaths per 100,000. In the world of cancer research where the competition for funding is fierce, you may rush a paper into publication that states that exercising can reduce breast cancer deaths by a third. However, suppose you do a little additional searching of the data base and sort the exercising and non-exercising groups by household income where you find that the death rate for breast cancer in both groups is much higher for low income households than high income households. You also find that, since high income households have more disposable income and more leisure time than lower incomes, a much greater percentage of exercisers belong to high income households. Consequently, your original exercise correlation was merely telling you that poor women have a higher breast cancer death rate than women who can afford more frequent doctor visits, regular screening, etc.

Purely statistical correlations such as the one I've hypothetically described above are entirely useless when it comes to reducing breast cancer rates. However, when they are used to identify mechanisms by which cancer cell growth is triggered, they can be a valuable tool. To continue the above example, suppose you used the exercising correlation to look into the hormone levels of exercisers and non-exercisers and found that the exercisers had lower levels of certain hormones that have been associated with cancer occurrences. This is useful information.

So...with this in mind, I went on the Internet to track down the source of the "one-third reduction" number. The report ended up being based on a talk given by Carlo La Vecchia at a conference in Barcelona. The source of La Vecchia's figures was cited to be a study by the International Agency for Research on Cancer. If you go to the IARC website, you'll find that the figures come from a report (Volume 6) that was written in 2002 and is now out-of-print. from an 8 year old report suddenly makes front page news. What the hell? First, understand that in any technical field, 8 years ago was ancient history. I am supposed to believe that a supposedly critical connection between diet and exercise and breast cancer was announced 8 years ago and that there have been no follow-up studies that have made more recent or updated data available? I think not. So what is going on here? Here are my best guesses:

1. Carlo La Vecchia wanted a boondoggle to the Barcelona conference, so he submitted an abstract for essentially a throw away talk using old data. Consequently, he gets the University of Milan to pay for his trip. Meanwhile, Maria Cheng, the AP reporter, is at the conference looking for something, anything, she can write a story on. La Vecchia mentions his 25 to 30 percent reduction in breast cancer number, Cheng grabs that, rounds it up to "one-third", makes a few calls to some breast cancer workers she knows who give her some broad general comments, and she's got an easy byline.

2. The story has an interesting quote by La Vecchia, "What can be achieved with screening has been achieved. We can't do much more. It's time to move on to other things." By "other things", the professor is obviously talking about preventing breast cancer through diet and exercise, which will, of course, require tens of millions of dollars in new funding to study...and as he has just established himself as the lead expert in this subject -- if only by dredging up some work probably done 10 years ago -- La Vecchia looks to be leader in the clubhouse as the recipient of a good chunk of that money.

3. A potentially darker interpretation of the timing of this story, since it is coming out of the Associated Press, who can't issue any story without injecting their political agenda into it, is that it is intimately connected to the recent health care debate. Anyone with a brain recognizes that the health care bill that just passed is going to result in higher taxes and reduced services -- if you don't believe this, please email and tell me about the rest of your life on Planet Pollyanna...I'll bet it's nice there. Taxes will go up, but tax increases are never very palatable to the American public, even during prosperous times. Any congress person that votes for a significant tax increase these days might as well go home and campaign for their successor. Reducing services is much easier to slip by the public, since they won't know they're missing them until they need them. Herein lies a possible subtext in the AP's story...if you're a fat woman, who drinks, doesn't exercise, and is diagnosed with breast cancer, then "I'm sorry, ma''ve brought this on yourself. We need to save our very expensive treatment for people who are more deserving. Why don't you go take a walk and quit eating Big Mac's?" The AP article mentions drinking (bad), exercise (good), and obesity (doubly bad)...I'm surprised they didn't go for the trifecta and throw in smoking.

Sunday, March 21, 2010

China...thoughts from one who's been there and returned.

A common topic among many conservative commentators is the looming threat of China as an implacable enemy intent on the destruction of the United States and our way of life. However, to the likes of Laura Ingraham and Rush Limbaugh, I have to say, "World communism as you knew it is dead. The harsh realities of the global marketplace drove a stake through the heart of that vampire in the late 80's." Is China an implacable enemy? Hardly. Are they our friend? Don't kid yourself...

To understand China today, you need to understand what really happened at Tienanmen Square. The impression that was left with the American public was that the powerful Communist government called in the full force of its military to brutally suppress a peaceful protest by Chinese students. A Chinese acquaintance who was a student at the time had a somewhat different story: The protest that was centered at Tienanmen Square was far more widespread than a collection of students and the military was called out only when the the government was faced with imminent collapse in what was quickly becoming nothing less than open rebellion in the populace. If we accept that this was the case, can Americans who moralize about the brutal government response at Tienanmen claim that our own government would respond any differently? I think not...

In any case, Tienanmen Square did serve as a wake up call for the Beijing government that economic reform was long overdue and, to their credit, radical and, literally, world-changing reform was made to happen in short order. The odd hybrid of socialism and capitalism, "planned capitalism" if you will, that exists today in China is the result of that reform. Nothing drove home to me the rapid and decisive nature of this change more than when I visited Beijing in late 1999 (ten years after Tienanmen Square) and found a McDonald's open for business across the street from Mao's Tomb. Ten years earlier, anyone standing at that spot would have been watching tanks running over students in the nearby square.

China has grown its economy over the past twenty years through the massive export of manufactured goods. It has, and still does, encourage foreign manufacturers to build plants in China as well as growing its own native manufacturing. This economic growth has provided for order of magnitude increases in the standard of living of the Chinese people, which of course, was the whole point of the post-Tienanmen economic reforms. However, this growth has not come without problems. There's an old joke that says, "Cocaine will make you a new man...and the first thing the new man wants is more cocaine." Prosperity is like that...once people get a little, they want more. Consequently, the Chinese government is faced with the dilemma of maintaining economic growth to feed the increasing demand for more "stuff" from the increasingly prosperous Chinese people.

Economic growth in China means continued export of manufactured goods on a massive scale, which in turn requires a healthy appetite for those goods in the world's dominant economy, i.e., the United States. A weak American economy threatens the economic health of China. China has lent hundreds of billions of dollars to the United States, not as part of a diabolical plot to destroy the U.S. economy, but as an almost desperate attempt to prop up the primary customer of Chinese manufactured goods. The lessons of Tienanmen Square are constantly on the minds of Chinese leaders. They stay in power only as long as the Chinese people are prosperous and economic growth continues.

China should be viewed as a fierce and determined economic competitor. The Cold War is over...capitalism won, but that is small consolation for the United States. Just as the most fervent Christian is the recent convert, China has not so much embraced capitalism as it has roped it, saddled up, and is riding it like a stolen horse. However, the economic growth that has stabilized Chinese society is not sustainable. Even now, wages in China are rising rapidly and I have spoken with Chinese factory owners who are seriously contemplating moving operations to Vietnam, among other places, to, ironically enough, take advantage of cheaper labor. The Chinese government has also started to recognize that their "growth at any cost" strategy has brought many areas of the country to the verge of environmental collapse - I've spent a lot of time in the industrial zone south of Shanghai and have yet to see anything resembling a blue sky and even tap water in downtown Shanghai is too polluted to drink. Correcting what can only be called "environmental atrocities" while necessary, will have a distinctly negative impact on China's global competitiveness. I don't know how the Chinese government will end up addressing the issue of economic sustainability, but I do know that whatever actions they take will dominate the world of Realpolitk for at least the next 20 years.