Book Review: Should I Be Tested for Cancer

Should I Be Tested for Cancer?: Maybe Not and Here's Why by H. Gilbert Welch, M.D., M.P.H.

This fascinating book explores the world of medical testing, especially for cancer, in otherwise healthy patients (or at least those that are not showing any symptoms of cancer). He states repeatedly that this book does not address testing for cancer in patients that already have symptoms. If you are feeling unwell, please see your physician. It also does not address the situations of people who have a strong family history of cancer which is proven to be influenced by genetics.

If, however, you feel perfectly fine, should you agree to mammograms or screenings for things like cervical cancer and colon cancer? Many such tests are standard fare for those of us with health insurance and regular doctor's visits. I'm not currently contemplating any tests for cancer, but I am seeing my OB constantly (or so it seems) and have faced the usual suggested prenatal tests so the idea of testing was recent in my memory. (Though it is not the topic of this blog post, we decided to decline most of the prenatal tests. Unless a result meant we'd invite someone else into the delivery room, we simply didn't need to know before the birth.)

You can learn a great deal simply by reading the introduction to the book. Dr. Welch gives a brief but thorough summary of his arguments in just a few pages.

I marked so many passages that I could not possibly share them all. In six chapters, Dr. Welch covers the main problems with cancer screenings, including:

• the small chance of benefit (that you will be in the minority of patients that have a treatable, aggressive cancer caught at just the right time), 
• the much larger chance you'll have a "cancer scare" (that you will have an abnormal test result that indicates you might have cancer when in fact you do not, or that your test results will continue to be abnormal with no doctor willing to diagnose cancer but also unwilling to give a clean bill of health),
• the chance of unnecessary treatment (believing you have cancer when in fact you have abnormal test results),
• the chance of finding (and treating) a cancer that would never have harmed you (either because the cancer is exceptionally slow-growing or because the "cancer" is one that does not actually result in detrimental health),
• the chances of disagreement on whether the tests show you have cancer, and
• the possibility that you and your doctor may focus too much attention on the cancer that might be rather than the problems you are currently facing.

Lots of evidence is presented showing the probabilities and possibilities of the above problems, including how difficult it is to test the benefits of testing itself. I found all of Dr. Welch's arguments convincing (though I was inclined to believe all of the above anyway, given our own mindsets and other books we've read like The Last Well Person: How to Stay Well Despite the Health-Care System, reviewed here).

Only so many people die from cancer, and only so many are ever bothered by symptoms. Could it be that our enthusiasm for cancer testing leads us to detect cancer in thousands of people who would otherwise never be affected by the disease? And given the uncertainty and fear associated with a cancer diagnosis and the harms of treatment, isn't it possible that many would be better off simply not knowing?

What I hadn't considered before was his last point, that your doctor may be so focused on the recommended tests (and the results, the follow-up tests, and so on) that the current worry or symptom that brought you to the office may be ignored. (I think, too, many doctors believe they've addressed a problem if a test was ordered and came back clean, even if the pain remains.) There's no evidence or data presented in the chapter, just the thoughts and experiences of Dr. Welch and his worries of his own patient-doctor interactions, but I found it an intriguing argument and quite logical.

Routine testing is really a concern for what could happen in the future. And worrying about what might matter in the future can distract your doctor from what matters now. The more time we spend ordering tests and following up on abnormal results, the less time we spend dealing with things that concern you now [...] I'm not suggesting we abandon all scheduled health maintenance and restrict ourselves to addressing current patient concerns. We can certainly do some of both. But I do want you to consider that even if there were no other downsides to cancer testing--that is, if it could only be beneficial--it still might distract from other, more useful activities. I also want you to be aware that testing in general increasingly dominates the physician-patient encounter.

Dr. Welch continues with the second part of the book: How our behavior as consumers of health care could by changed with more knowledge.

I was particularly interested in his account of an evaluation of the use of mammography for women aged 40 to 50 by the National Cancer Institute (discussed on pages 126-128 in the book). The panel presented its findings, essentially "the benefits of mammography were simply too close to call" and that women should talk with their doctors and make individual decisions rather than depend on set guidelines for the entire population. Doctors (including radiologists, who of course stood to lose a lot of business if all those women decided against mammograms) and politicians were in an uproar.

This example highlights some of the forces that work to preclude rational discourse about research findings on cancer testing. There will always be an asymmetry among testing proponents and detractors. Testing proponents have a very strong interest (often financial) in promoting tests--much more so than the researchers trying to critically evaluate them.

One of the points Dr. Welch makes in the book is how we should each think about what we want from our medical care and how we want to live our lives. If cancer screenings are going to increase your anxiety about your own medical health, are they beneficial?

As I said in the introduction, the dominant cancer prevention strategy in American medicine today is to look for cancer in people who have no symptoms. Given the problems discussed in this book, you will want to gauge your own reaction to this approach. How we perceive health is a choice: you may assume you are healthy until proven otherwise or assume that a problem may exist until proven otherwise. How much effort, emotional and otherwise, do you want to devote to looking for things wrong when you feel well? To what extent would you rather focus on being well when you feel well?

Dr. Welch presents some concrete steps we can take to work with our doctor to determine the level of medical testing we want and when.

Despite the complexity of the field of medicine and specifically the complications of medical research, Dr. Welch does an excellent job presenting the data and his arguments in a clear way, even for those without medical training. (I admit I have a bit of an advantage, dated those it may be, by my background as a student of biology and research.) There is also a glossary at the back of the book for any tests, diseases or medical terms that may be unfamiliar.

I highly recommend this book.