Is Radioiodine Tx Overused In Low-Risk Thyroid Cancer?

Target Audience and Goal Statements:

Endocrinologists, oncologists, nuclear medicine specialists, internists, primary care physicians, surgeons, family medicine specialists

The goal of one study was to determine whether patients with low-risk papillary thyroid cancer (PTC) are being overtreated with radioactive iodine (RAI); the goal of the second study was to investigate whether patients with differentiated thyroid cancer for whom RAI was “selectively” recommended felt pressured by their physicians to undergo RAI, felt a lack of real choice in deciding on treatment, and underwent significantly more overtreatment than warranted.

• Is RAI treatment for low-risk papillary thyroid cancer overused, and if yes, by how much?
• Do patients, for whom treatment guidelines currently recommend “selective” use of RAI, feel they had a choice about receiving this treatment, and if not, did that increase the risk of overtreatment?
• How did this perception affect patient treatment satisfaction?

Study Synopsis and Perspective:

A quarter of patients with low-risk papillary thyroid cancer received RAI treatment despite current guidelines that do not recommend radiation treatment for that diagnosis, according to researchers.

Physicians treated 4,300 of 17,236 patients with RAI even when it was not recommended according to the American Thyroid Association (ATA) clinical guidelines. RAI-treated patients underwent total thyroidectomy and more extensive lymphadenectomy significantly more often when compared with patients with the same diagnosis who did not get RAI, reported Alliric I. Willis, MD, of Thomas Jefferson University in Philadelphia, and colleagues in Surgical Oncology.

The association between RAI and more aggressive surgery for low-risk thyroid cancer could reflect a more aggressive clinical practice environment, they hypothesized.

“This is where guidelines, such as those outlined by the American Thyroid Association, can really help,” Willis said in a statement. “The guidelines can say this more extensive treatment is unnecessary. You will not have better outcomes because of it.”

A second study in the Journal of Clinical Oncology indicated that a majority of patients with differentiated thyroid cancer for whom RAI was “selectively” recommended felt they had no choice about RAI treatment, particularly when their physicians were perceived as strongly recommending it.

Patients who felt they did not have a choice were more likely to be unsatisfied with the treatment decision, reported Megan R. Haymart, MD, of the University of Michigan Health System in Ann Arbor, and colleagues. And overall, this resulted in overtreatment with RAI.

According to 2016 ATA guidelines, patients with low-risk thyroid cancer do not routinely require RAI ablation. More specifically, the guideline authors stated that postsurgical RAI is not indicated for patients with T1a N0/Nx M0/Mx disease.

In low-risk thyroid cancer, RAI confers no survival benefit, both authors observed. Moreover, use of RAI when not indicated may expose patients unnecessarily to several risks, including second primary malignancy and greater financial burden.

Willis and colleagues used the NCI Surveillance, Epidemiology, and End Results (SEER) database to identify patients treated for newly diagnosed thyroid cancer during 2011 to 2013. They compared patients with, and without low-risk disease, and sought to identify characteristics of low-risk patients who received postoperative RAI.

Patients with low-risk disease were older (age 51.3 vs 48.5), more likely to be white (69.7% vs 62.0%), more likely to be female (81.6% vs 71.7%), and more likely to be insured (87.6% vs 85.6%, P<0.001 for all).

With respect to disease/clinical factors, patients with low-risk thyroid cancer more often had T1 disease (99.5% vs 41.8%), underwent total thyroidectomy less often (80.2% vs 94.1%), and more often had no lymph nodes removed (59.7% vs 27.4%).

Comparison of the 4,300 low-risk patients who received postoperative RAI with 12,936 who did not show that RAI treatment was significantly (P<0.001) associated with male sex, and:

• Younger age: 49.9 vs 51.8
• Hispanic ethnicity: 14.2% vs 11.8%
• Asian ethnicity: 10.7% vs 8.6%
• Insurance: 88.9% vs 87.2%
• Total thyroidectomy: 94.9% vs 73.3%
• Lymphadenectomy: 44.1% vs 37.0%

By multivariable analysis, predictors of overtreatment with RAI for low-risk disease were age <45 (OR 1.393, 95% CI 1.250-1.552), ages 45-64 (OR 1.275, 95% CI 1.152-1.412), male sex (OR 1.191, 95% CI 1.086-1.305), Hispanic (OR 1.236, 95% 1.110-1.376) or Asian ethnicity (OR 1.306, 95% CI 1.159-1.473), and more extensive lymphadenectomy (OR 1.243, 95% CI 1.119-1.381).

Study limitations included the derivation of data from a national database, which could include coding errors and missing data. Also, data regarding certain high-risk tumor features, such as aggressive histology, were not available.

Haymart and colleagues examined patient perception of choice in RAI treatment. This study included 2,632 patients from the Georgia and Los Angeles SEER registries, treated for differentiated thyroid cancer during 2014 and 2015. The authors focused on 1,319 patients who met criteria for “selective” use of RAI.

Survey participants were asked whether they felt that had a choice in the decision to receive RAI, how strongly their physicians recommended RAI, whether they received RAI, and how satisfied they were with the treatment decision. The results showed that 75.9% of patients received RAI, and that 55.8% of the patients felt they did not have a choice in the decision about RAI.

The results suggested “a need for more shared decision making to reduce overtreatment,” the authors concluded. – Medpage Today