GLP-1 Meds Not Linked to Common Thyroid Cancers, Report Finds

Current human data do not show a link between GLP-1 receptor agonist medications and the most common types of thyroid cancer, according to a a white paper issued by the Clayman Thyroid Center.

As medications such as Ozempic, Wegovy and Mounjaro increase in popularity for the treatment of diabetes and weight loss, this comprehensive review aims to educate patients with cancer and their caregivers on the scientific evidence regarding potential risks, according to a news release. The white paper concludes that much of the existing fear surrounding these drugs is driven by a misunderstanding of the data rather than strong evidence in humans.

Main data that support the findings

The central finding of the white paper is that these medications do not appear to cause or affect the most common forms of thyroid cancer. These common types account for more than 95% of all thyroid cancer cases.

According to the review, the FDA boxed warning currently tied to GLP-1 medications is specific to a rare form of the disease known as medullary thyroid carcinoma. The authors noted that thyroid cancer is not a single disease and the distinction between subtypes is critical for understanding risk. For patients with papillary, follicular or Oncocytic (Hürthle cell) thyroid cancers, the evidence does not support the idea that GLP-1 medications cause these diseases or make them worse.

The data suggest that some studies showing a possible association between the drugs and cancer may be the result of detection bias.

"When diagnoses rise shortly after starting a medication, that pattern often reflects finding something that was already there," said Dr. Rashmi Roy, co-author of the white paper. "That is very different from a drug actually causing a new cancer."

Patients using GLP-1 therapy typically have more medical appointments, specialized care and diagnostic imaging. This increased medical surveillance makes it more likely that a physician will discover a small cancer or a pre-existing thyroid nodule that would have otherwise remained undetected. The authors noted that when cancer diagnoses rise shortly after a patient starts a new medication, it often reflects the discovery of a condition that was already present rather than the drug causing a new cancer.

More details into the research

The white paper reached its conclusions by examining a wide range of information, including mechanistic research, clinical trials, real-world clinical experience and large population studies.

The review highlighted that the initial FDA warnings originated from rodent studies. In those trials, animals exposed to GLP-1 drugs developed C-cell tumors. However, the white paper emphasizes that important biological differences exist between rodents and humans. Large human studies, including major international cohort studies and meta-analyses, have not demonstrated the same patterns seen in the rodent models.

The authors also drew upon clinical data from the Clayman Thyroid Center, which is among the highest-volume thyroid centers in the world. The center treats approximately 2,000 patients with thyroid cancer every year. Within this large practice, surgeons reported that they have not observed a pattern linking the use of GLP-1 medications to medullary thyroid carcinoma. Dr. Gary L. Clayman, senior author of the paper, noted that in a practice seeing more thyroid cancer than almost anywhere globally, they are not seeing a surge of medullary thyroid cancer linked to these medications.

While the white paper offers reassurance regarding common thyroid cancers, it maintains that safety precautions are necessary for specific groups. GLP-1 receptor agonists remain contraindicated for patients who have a personal or family history of medullary thyroid carcinoma. Additionally, the medications should not be used by individuals with Multiple Endocrine Neoplasia type 2 (MEN2). These recommendations are consistent with current FDA labeling.

The authors expressed concern that oversimplified summaries on social media and in headlines can blur the distinctions between different cancer subtypes. This confusion may lead patients to experience unnecessary anxiety or stop taking beneficial medications.

For the vast majority of patients, the authors suggest that decisions regarding GLP-1 therapy should be individualized. Patients and their physicians should consider the metabolic benefits of the drugs and the patient’s overall health goals.

"In a practice that sees more thyroid cancer than almost anywhere globally, we are not seeing a surge of medullary thyroid cancer linked to these medications," Dr. Gary L. Clayman, senior author of the white paper and thyroid cancer surgeon. said.

"Patients deserve clear, evidence-based guidance," Roy concluded. "Our goal is to provide clarity so people can make informed decisions with their physicians."

References

1. “Nation's Largest Thyroid Cancer Center Publishes White Paper Finding No Convincing Evidence That GLP-1 Medications Cause Common Thyroid Cancers,” by the Clayman Thyroid Center. News release; Feb. 12, 2026.

Editor's note: This article is for informational purposes only and is not a substitute for professional medical advice, as your own experience will be unique. Use this article to guide discussions with your oncologist. Content was generated with AI and reviewed by a human editor.

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