The Problem of Overscreening

problem with overscreening thryoid cancers

I just read an interesting op-ed piece in today’s NY Times on the dangers of overscreening for thyroid cancers.

I’ve posted a couple of times on here about thyroid cancers. If you remember this post from a few months ago, you’ll recall that the large majority of thyroid cancers are papillary cancers. Autopsy studies have shown that about 1/3 of American adults have small papillary thyroid cancers as an incidental finding at their deaths (from other causes).

So, there are huge numbers of these small cancers out there which mostly are causing no symptoms and aren’t killing anyone.

The above article describes the South Korean experience, where a nation-wide screening program for thyroid cancer was instituted some years back. Over that time, the number of diagnosed thyroid cancers increased by a factor of 15! However, the death rate due to thyroid cancer did not change at all (because the undiagnosed cancers weren’t killing anyone).

In the US, we have seen a 3-fold increase in the diagnoses of thyroid cancer over the same period (without a formal screening program).

The author of the Times article argues that we are actually causing harm by aggressively screening for early thyroid cancers (the majority of which will likely never cause symptoms or deaths).

I believe he has a point. The treatment for thyroid cancer (surgical removal of the entire thyroid gland followed by postoperative radioactive iodine treatment) is not without complications and side effects. There is also the fact that the patient will have to be treated with thyroid supplements for the rest of their life, which can sometimes be challenging for doctors to maintain the right levels of hormone.

Perhaps we should be less aggressive in searching for thyroid lesions. This is easier said than done, though.

Patients worry when they hear the word “cancer,” and it’s hard to argue that a known cancer should be watched. The American Thyroid Association guidelines continue to recommend against watchful waiting for even small papillary cancers.

I will continue to offer diagnostic testing (needle biopsy) for thyroid nodules and surgery for symptomatic benign nodules and cancers. However, I will be diligent in laying out all the options for my patients, whether treatment or no treatment.