Is Ozempic Contributing to the Overdiagnosis of Thyroid Cancer in the U.S.?

Recent research suggests that weight loss medications, particularly GLP-1 receptor agonists like Ozempic and Wegovy, may be linked to a potential increase in thyroid cancer diagnoses across the United States. However, experts are indicating that these drugs are unlikely to be the cause of the disease. Instead, the increased screening rates among users of these medications could lead to the overdiagnosis of thyroid cancer.

A study recently published in JAMA Otolaryngology—Head & Neck Surgery highlighted that individuals taking weight loss drugs are screened for thyroid cancer more frequently than the general population. This finding raises important questions about whether these medications truly increase cancer risk or simply contribute to heightened awareness and screening.

Key Findings from the Study

• The study showed that individuals using GLP-1 receptor agonists were diagnosed with thyroid cancer more often than others.
• However, researchers believe this is due to increased screening rather than an actual cause-and-effect relationship.
• Dr. Rozalina McCoy, an expert in the field, stressed that “more cancers are being identified, primarily due to increased imaging opportunities like ultrasounds.”
• This screening trend can lead to the detection of benign nodules, resulting in unnecessary cancer diagnoses even among the broader population.

According to Dr. Zachary Zumsteg, a noted researcher, “the incidence of thyroid cancer has plateaued since 2009, yet overdiagnoses remain prevalent without any noticeable decline.”

Understanding GLP-1s and Thyroid Cancer

The intention behind the study by Dr. McCoy and her team was to reassess the risks associated with GLP-1 drugs and thyroid cancer. Historical data from a 2010 animal study indicated a link between long-term exposure to liraglutide and medullary thyroid cancer in rodents, prompting a warning about these drugs.

However, subsequent human studies showed no substantial increase in thyroid cancer risk for those using GLP-1s. The recent investigation encompassed data from over 351,000 adults who had recently started these medications with a background of type 2 diabetes but no previous thyroid cancer history.

• Initial findings hinted at a somewhat elevated risk of thyroid cancer diagnoses.
• Nonetheless, a careful examination revealed that this risk was apparent only within the first year of commencing GLP-1 therapy, causing researchers to question its validity given cancer’s long development process.
• Significantly, the study confirmed that users of GLP-1s are far more likely to undergo thyroid imaging.

Dr. McCoy noted, “The screenings primarily detect existing nodules, many of which would remain clinically insignificant if not found.”

The Bigger Picture: Why Thyroid Cancer is Often Overdiagnosed

Many experts agree that thyroid cancer overdiagnosis is a broader issue tied to increased medical imaging practices, such as CT scans and MRIs. These screenings for unrelated health issues often identify nodules that could be benign yet labeled as cancerous.

• Richard Siegel, MD, pointed out that finding these nodules usually does not dramatically change patient outcomes.
• “The general mortality rate for thyroid cancer remains exceptionally low,” he explained.
• With the most common type, papillary thyroid cancer, having a 99.5% five-year survival rate, it also leads to the diagnosis of many nodules that are of little concern.

Dr. McCoy believes that users of GLP-1 medications face a similar situation due to the heightened vigilance created by black box warnings. This leads both patients and healthcare providers to be more proactive about screenings.

Should Users of GLP-1s Be Concerned About Thyroid Cancer?

In general, experts maintain that users of GLP-1 drugs should not worry excessively about an increased risk of thyroid cancer. “The animal studies raising this concern don’t effectively replicate human conditions,” Dr. McCoy noted.

• Dr. McCoy reassured her patients, saying, “They can take GLP-1s safely; concerns about thyroid cancer should arise from other factors.”
• Individuals with a family history of thyroid cancer or certain genetic disorders like multiple endocrine neoplasia type 2 (MEN2) might have elevated risks.
• Additionally, exposure to high radiation levels can enhance the likelihood of developing thyroid cancer.

Experts encourage anyone worried about their thyroid cancer risk to have an open discussion with their healthcare provider. Despite the rising awareness surrounding thyroid cancer, it’s crucial to remember that both GLP-1 users and the general public experience a relatively low risk of this disease.

As Dr. Siegel aptly observed, “In essence, we are sometimes victims of our own advanced medical technology.”