Will Using Semaglutide Increase Your Risk of Thyroid Cancer?

New research indicates GLP1-RA medications do not increase thyroid cancer risk, reassuring users and clinicians.

A new study, published in the peer-reviewed journal Thyroid, the official journal of the American Thyroid Association, found no evidence linking the use of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) to an increased risk of thyroid cancer.

What are GLP1-RAs?

Glucagon-like peptide 1 receptor agonists (GLP1-RAs) are incretin-based glucose-lowering medications commonly used in the management of type 2 diabetes and obesity. They function by mimicking the action of glucagon-like peptide-1, a hormone naturally released from the gut after eating. GLP1-RAs help to regulate blood glucose levels by:

• Stimulating insulin release from the pancreas when blood glucose levels are elevated.
• Slowing down gastric emptying, thus promoting a feeling of fullness and reducing appetite.
• Reducing glucagon secretion, which lowers glucose production in the liver.

Commonly prescribed GLP1-RAs include Ozempic (semaglutide), Victoza (liraglutide), and Trulicity (dulaglutide).

Why Were There Concerns About Thyroid Cancer?

Initial concerns regarding thyroid cancer risks associated with GLP1-RAs emerged primarily from preclinical animal studies. In rodents, exposure to certain GLP1-RAs was associated with increased incidence of thyroid C-cell tumors. These findings prompted regulatory agencies, including the U.S. Food and Drug Administration (FDA), to require thyroid cancer risk warnings on GLP1-RA medication labeling.

Professor Anton Pottegård, from the University of Southern Denmark, and coauthors analyzed databases from six countries, comparing patients with type 2 diabetes between 2007 and 2023 for the risk of thyroid cancer among GLP1-RA users compared with dipeptidyl peptidase-4 inhibitors (DPP-4is). The investigators examined data from 92,497 users of GLP1-RA and 2,484,408 users of DPP-4i.

“In this large multisite study, utilizing data from six population-based databases, we found no evidence that GLP1-RA use is associated with an increased risk of thyroid cancer with follow-up ranging from 1.8-3.0 years, providing some reassurance to patients and clinicians about the short-term safety of these drugs,” concluded the investigators.

Reference: “Glucagon-Like Peptide 1 Receptor Agonists and Risk of Thyroid Cancer: An International Multisite Cohort Study” by Sarah M. Baxter, Lars Christian Lund, Jacob H. Andersen, Thomas H. Brix, Laszlo Hegedüs, Miyuki Hsing-Chun Hsieh, Chris Tzu-Ting Su, Michael Chun-Yuan Cheng, Zoe Chi-Jui Chang, Edward Chia-Cheng Lai, Swaleh Hussain, Cherry Chu, Tara Gomes, Tony Antoniou, Antoine Eskander, Zachary Bouck, Mina Tadrous, Sungho Bea, Eun-Young Choi, Ju-Young Shin, Karin Modig, Mats Talbäck, Rickard Ljung, Hanne Løvdal Gulseth, Øystein Karlstad, Blánaid Hicks and Anton Pottegård, 16 January 2025, Thyroid.