Map of life expectancy at birth from Global Education Project.

Wednesday, July 31, 2013

What's in a name?

If the name is "cancer," plenty. When people are told they have cancer, they ordinarily are terrified. And they and their doctors feel compelled to do something about it. Doing something about cancer normally means surgery, chemotherapy, radiation -- all extremely expensive, unpleasant, and in fact damaging to your health.

It turns out, however, that since we've undertaken massive programs to screen the general population for what is generally called cancer, we've been detecting a lot of phenomena which, if untreated, would never hurt anyone. But the doctor tells the person "You have cancer," and  off we go.

The National Cancer Institute convened a working group to, well, work on this problem, and a summary of their group working is posted on the JAMA web site. They'll even let you read it!

They give a careful explanation of issues I have often discussed here, and I think it would be good for lots of people to read this and understand it. The mass hysterical freakout we've experienced every time the Preventive Services Task Force recommends less cancer screening is proof that people just don't get it.

The key ideas are:

Some abnormal cells that look like cells that sometimes become cancerous never in fact do so. In many cases, we really can't tell the difference.

The importance of early detection of cancer, or what might become cancer, has been exaggerated. The American Cancer Society is as guilty of this as anyone. Yes, five year survival is higher with lesions detected by screening than lesions that are detected because they are symptomatic; but that's largely because a) some of them were completely harmless to begin with and b) others would eventually become harmful, but they would not have killed you within five years even if untreated. What we really need to look at is whether, over the long term, the death rate from a form of cancer goes down in a screened compared to an unscreened population. This is difficult because you can't really do a controlled experiment, but the best evidence shows that general mammographic and prostate specific antigen screening have very small effects on population mortality. (In fact, the evidence is somewhat mixed. Some people aren't convinced it does significant good at all.)

The benefits of screening are offset by the costs, which include "overdiagnosis" -- finding those lesions that aren't going to hurt you and scaring you, treating them with all the attendant harm, and spending tens or hundreds of thousands of dollars. So yes, we need to strike an appropriate balance.

Good ideas include focusing tests on higher risk people, screening less frequently where indicated (and this has to do with parameters such as how fast a cancer tends to grow), and maybe abandoning screening entirely, as many people recommend with respect to PSA.

The working group has one more good idea: don't call it cancer when it isn't. For example, so-called ductal carcinoma in situ is not carcinoma. (Carcinoma is cancer arising from epithelial cells of ectodermic origin. That's fancy anatomy, look it up if you care.) Similarly with some prostate lesions. Instead of calling these "cancer," they want to call them Indolent Lesions of Epithelial Origin, or IDLE conditions. (Yes, the correct acronym would be ILEO, but evidently IDLE sends the right message.) If you're told you have an IDLE condition, rather than cancer, you won't freak out, and you'll be more likely to say okay, what the heck, let's not do anything and just keep an eye on it.

Seems like a good idea, but will doctors do it? We'll see.


kathy a. said...

i'm really interested. both my aunt and my SIL had DCIS -- my aunt referred to it as "pre-cancerous" but my SIL called it cancer, had a lumpectomy and radiation, and started collecting things covered in pink ribbons.

one of my sisters had a very aggressive breast cancer, diagnosed at stage II (fortunately now in remission). so, my daughter has some family risk on both sides -- but it seems to me better to be able to distinguish low-risk changes from very high risk ones.

Cervantes said...

Probably, given your family history, you or your daughter would be advised to choose a relatively aggressive approach to DCIS. But calling it cancer wouldn't help people in that position make a clear-eyed decision. "Pre-cancerous" isn't exactly right either, because that seems to imply that will inevitably become cancer.