Thursday, August 22, 2013

Do I really want to know? How will knowing be helpful?

This is my question to you:  Do you want to know?

You say you do. You may think you do. But, do you really?  Do you really really want to know?

This may seem like a trick question, but I am not being sly. I promise. Let's be clear here. This is your body, your health, your life, not mine.

And before we proceed, one word of warning: once you know, you cannot un-know. 

If after pausing a moment to ponder the question, you are now leaning in the direction of answering something to the tune of, "Yes, insanely weird doctor, I definitely always want to know. Please order the test."-- then please now ask yourself a few follow-up questions.  Will knowing be helpful? What if it comes up positive? Or negative?  Can I do anything with the information? (Other than stay up at night worrying and/or searching the Internet for an answer). Will it change the outcome? Does the information give me options? And perhaps most importantly: Will it make my life longer and better and richer and fuller?

Patients often look at me like I am totally insane when I ask them the 'do you want to know' question-- as though knowing is always better than not knowing. Just today, my patient looked stunned when I questioned her request for an imaging study of her brain. She looked at me suspiciously (as though I was suggesting we maybe sacrifice her dog) and asked, "What do you mean there could be something inside of me that I don't want to know about? How in the world could knowing make things worse?"

Many of us assume that all medical information equates to useful information. And perhaps, even more tightly embraced is the notion that the more medical information we have, the better off we are. This is deeply embedded in our American ethos and exemplified by our outrage that there is actually a waiting period in Canada to get an MRI.  As your clinician, I want to challenge this notion.

Yes, medical information can be amazingly powerful (e.g. Congrats, you're pregnant! No, you don't have HIV. You are cancer free. Your heart is working just fine). However, medical information is not always useful--and, I would argue, it can even be remarkably unhelpful.

There are two reasons I encourage you to be careful about what you ask for: First, you might find out something you don't actually want to know and second, what you find out may not matter at all.

Hear me out:
1) Incidentalomas: Yes, definitely looks (and sounds) like a fake word, but believe it or not, this is actually a term we use with some frequency in medicine. Incidentalomas are things "incidentally found" when we are looking for something else-- often the result of an imaging study like a CT scan or an MRI scan. In other words, we found something we weren't looking for.

Consider this example:  Dr.Careful wants to be sure his patient, Lina, doesn't have appendicitis, so he orders a CT scan of her abdomen. Thankfully, the CT scan confirms that Lina's appendix is totally normal, and she is able to avoid surgery. However, in the scan report, Dr. Careful discovers that Lina has some funky little blip on her kidney. Now what? Is the blip causing her pain? Is it cancer? Is it important? Who the heck knows?!?

Occasionally incidentalomas are blessings-- because we find a tumor that would have taken a long time to appear and is still in its early stages, so treatable or curable. However, more often, incidentalomas are just pains in the rears. We (clinicians and patients)  feel compelled to investigate further that silly little incidentaloma, which often means more tests, more imaging (i.e. more radiation exposure), and even unnecessary surgery. And often, the incidentaloma would have just lived happily ever after tucked away in our belly never causing problems. Here is a great case in point written in the NY Times awhile back. Interestingly, in the end, the columnist doesn't complain about how he had unnecessary surgery. Instead he marvels about a greater "appreciation for the glory of life". I don't know about you, but I'd hope to be able appreciate the glory of my life life sans unnecessary scans and definitely without unnecessary surgery!

2) True positives that we don't actually care about. The example that always comes to my mind for this phenomenon is that of prostate cancer (more on PSA in another post). But for now, you should know that somewhere in the ballpark of 60% of men after age 60, 70% of men after 70, 80% of men after 80, and 90% of men after 90 will have prostate cancer. Did you catch that? That is, if you open up a 90-year-old man's body after he dies from whatever cause, you will find that he has actual real live cancer in his prostate. The numbers are impressive! 

However, the numbers of men for whom prostate cancer causes death or even illness is much much lower. Though 1 in 6 men will be diagnosed with prostate cancer in their lifetime, only 1 in 36 will die from prostate cancer. A recent 2012 study  randomized 731 men with localized prostate cancer to radical prostatectomy (i.e. really big surgery with lots of side effects) versus observation (i.e. just watch and wait, no surgery). They found NO difference in the numbers of men who died. None. In this study, in fact, only 7% of men with known prostate cancer (in both groups) actually died as a result of prostate cancer, and it didn't matter if they were treated or not. This begs the question, did knowing and treating prostate cancer improve these men's lives? Did it make them healthier and happier? Was knowing better?


Okay, enough blathering for now. You get my point, I hope. What I want you take home is that the decision to take a test or have a scan is not a black or white one, but rather one that requires communication with your provider and the ability and space to ask some serious questions. I am not saying don't get the test, I am only asking you to be an empowered patient and ask yourself and your clinician two questions, "Do I really want to know? How will knowing be helpful?"

In case you are interested, here is a quick list of tests that I would want to talk about with my patients before ever ordering or even considering. Certainly doesn't mean I would NEVER order them as a physician (there are clear times and places when these tests are super important) or never get them as a patient, but I would just be mindful before taking the leap:

1) MRI of the back for low back pain (Unless you have clear neurological symptoms, routine MRI has not been shown to improve patients' health) more info
2) CT scan of the belly (especially for vague reasons, You should know that a single CT scan of the belly = 769 chest x-rays of radiation exposure!) more info
3)  PSA (prostate specific antigen, controversial screening test for prostate cancer for men, touched on above) more info

4) Prenatal genetic screening (tests women get in first and second trimester of pregnancy, offered to all pregnant women) more info
5) HPV testing (in the presence of a normal pap smears--26% of us will test positive. That's a lot of partner disclosing!) more info
6) Genital herpes blood test (1/6 of us will test positive!) more info

Each of these examples could be a post in and of themselves. And time, allowing, I promise to write on each of these. For now, I welcome your thoughts and your questions.


  1. I agree with this wholeheartedly. Though this might sound odd, I feel that way about testing for the BRCA gene. Eventually I will get it done but given my family history of breast cancer (every woman except for two have gotten it) even if the test came back negative I will still assume I will get breast cancer. The test will give me little piece of mind because statistically people still get breast cancer without the gene. My sister got the test and assumes now she will not get breast cancer, which is a dangerous attitude. And what does one do mammogram-wise? Get more mammograms and expose oneself to more radiation (they recommend I get mammograms 10 years prior to my mom's diagnosis which would have been two years ago) or wait until I'm older? It's hard to know when the tests do more harm than good.

  2. Thanks, Nicole. I totally get what you are saying about the BRCA issue for you and your family. And it's funny, my original draft included "False negatives that are falsely reassuring", but then I took that part out. The example you give about your sister highlights the false assumption that a negative tests means that you won't get sick. This comes up often with genetic screening for pregnant women. As for the mammos for you, super uber tricky question. No perfect answer (as usual). And when there is no perfect answer, I often fall back on choosing the timing/decision that feels the best for you (i.e. least anxiety, least risk, most reassuring, etc). Hard stuff!