Time to Rethink Thyroid Nodule Biopsies?
A new study makes a case for reducing the fairly aggressive surveillance that’s recommended for thyroid nodules. The results of the study, published in the journal JAMA, found that these abnormal growths of thyroid tissue are very slow growing if they grow at all. Yet guidelines recommend frequent follow-up and testing to monitor the nodules for cancer.
There’s been a surge in thyroid biopsies to detect thyroid cancer, and experts want to slow the trend. The American Thyroid Association is revising its guidelines for the treatment of thyroid nodules, and expects to publish the guidelines sometime this fall.
Use of thyroid fine needle aspiration, an uncomfortable procedure in which a radiologist makes several pokes into your neck to withdraw fluid from the nodule, more than doubled between 2006 and 2011. During that same time the number of thyroid operations performed for thyroid nodules increased by 31 percent. Total thyroidectomies increased by 12 percent per year.
But experts worry that the majority of these procedures are unnecessary. Studies show that about 50 percent of us have thyroid nodules, abnormal growths of cells within the thyroid gland. But most of us will never know we had them, or would have never known if it weren’t for all the imaging we undergo. Nodules are typically found incidentally during testing for other conditions. But what typically happens after a nodule is found is the problem.
Current guidelines state that people should have ultrasounds to locate and measure the nodules. If a nodule is bigger than 1 cm, a fine needle biopsy is recommended, though sometimes factors like the number of nodules and their characteristics are considered. If the nodule is benign, you’re advised to have repeat ultrasounds every six to 18 months to watch it for growth. Then have more needle biopsies if it grows more than 20 percent.
The JAMA study, however, found that the vast majority of nodules don’t grow much during a five year period and some actually decrease in size. Only 15 percent of nodules showed significant growth.
“One of the goals of surveillance is the prompt detection and treatment of thyroid cancers that arise during follow-up or have been missed on the initial assessment,” the study’s authors wrote. “In the population we studied, these events were rare.”
What’s more, only 7 patients (or 0.7 percent of the study population) were diagnosed with thyroid cancer during the five years of follow-up, and in two people, the cancer arose in a new nodule, not one that was being watched.
The authors said their results suggest after a benign finding, that nodules “can be safely managed with a second ultrasound examination 1 year after the first (early follow-up) and in the absence of changes, reassessment after 5 years (long-term follow-up).”
More frequent monitoring may be appropriate for nodules occurring in younger patients or older overweight individuals with multiple nodules or large nodules (>7.5 mm), or both.
“The one-size-fits-all approach simply does not work,” wrote Anne R. Cappola, MD, and Susan J. Mandel, MD, in an accompanying editorial in JAMA.
Instead, surveillance strategies should be individualized based on a nodule’s characteristics. All four cancers that arose in the previously biopsied nodules were associated with a suspicious feature.