Director's Message: May 18, 2010

On May 6, the President’s Cancer Panel issued a report to the White House that made a bit of a splash—editorials and commentaries in newspapers including a piece by Nicholas Kristof in the New York Times.

The bottom line was that the “true burden environmentally induced cancers has been grossly underestimated.” The panel advised President Obama to use the powers of his office to remove carcinogens and toxins from our food, air and water as an urgent priority.

The report had some impact. Kristof, who is someone I read fairly often because he tells me things that I tend to agree with, concluded that we should eat organic food, change water storage methods and check for radon exposure in our homes.

Kristof also made the point that this isn’t just a recommendation from a bunch of wackos: It’s from the President’s Cancer Panel, a group of real experts. Maybe.

While the President’s Cancer Panel member are indeed not wacko, they are also not the final word on all things cancer. In fact, this three-person panel has just two current members because President Obama hasn’t appointed someone to fill a gap yet. I’m not sure of the dictionary definition but I think it’s hard to be a “panel” if you’re just two people.
A better example of a critical report on cancer is this: a committee of more than a dozen leading experts comes to consensus on an issue, such as a recent report from the Institute of Medicine about how to reinvigorate cancer clinical trials in the United States.

The American Cancer Society highlighted a problem in the President’s Cancer Panel report that I agree with. While chemical exposure can be associated with elevated cancer risk, the President’s Cancer Panel report may give people the impression that chemicals in the environment are the BIGGEST risk factor. If a smart guy like Nicholas Kristof gets that impression, its not just overreaction from folks who don’t know any better.

As far as I can tell, the Cancer Panel report is running the danger of presenting hypotheses as firmly established fact. We really don’t know how much cancer risk is associated with environmental chemicals. The problem (and this is where I personally tend to agree with the ACS position) is that it may give the false impression that other modifiable risks are not as important.

My fear is that if we focus on chemicals, an average person might think that if they filter their drinking water and buy organic potatoes they are significantly reducing their cancer risk. Water filtering and eating organic aren’t bad, but reports like the Cancer Panel’s may suggest that ways we know we can reduce cancer risk, like not using tobacco, maintaining a healthy weight and reducing sun exposure, are maybe not so important.

It makes sense to reduce radiation exposure through encouraging radon testing, limiting exposure to known carcinogens like benzene and limiting the amount of radiation exposure through medical screening and other interventions. But I don’t want people to think that the risk of radiation exposure from cancer screening is as big as the risk of the disease unless that’s true (and it almost always won’t be).

I certainly think that better understanding (i.e. more research) on the effects of chemicals is sorely needed. But there are lots of things we need to do research on. Are we really going to carefully analyze 80,000 chemicals without taking resources away from other areas of research that will have a bigger impact?

I fear that we run the risk of diluting our message, that people get further confused by all the information that is thrown at them about things that are “good” or “bad” as regards cancer. And, if we continue to confuse them, we risk sending entirely the wrong message.

It would be a pity if the President’s Cancer Panel Report ends up making people think that environmental chemicals are the biggest problem that we need to deal with. Those of us in the cancer world should focus on ensuring clear messages about what we do know about big, avoidable cancer risks (tobacco, obesity, sun exposure), and if we add things to that list such as chemical exposure, we should do so with a similar level of confidence that our messages are indeed fact and not hypothesis.

And, we should make sure we’re clear about which of these provide the highest risks to people and make sure we convey the message that dealing with tobacco and the like should be our first priority.

Sincerely,

Andrew Thorburn
Interim Director
Associate Director for Basic Science
Grohne Chair for Basic Cancer Research