Research

Hormonal

GLP-1-based therapies are associated with an increased risk of thyroid cancer, specifically medullary thyroid cancer and papillary thyroid cancer, due to GLP-1 receptor expression in thyroid C-cells and papillary cancer cells.

If you are taking a GLP-1 drug, be aware of the potential risk of thyroid cancer. If you notice a lump in your neck, hoarseness, or difficulty swallowing, seek medical attention immediately. The paper suggests this risk is real and mechanistically plausible, not just a rare side effect.

ModerateSupportsMEDIUM confidence
Moreover, GLP-1 receptor expression is also present in 20% of those with papillary thyroid cancer, a much more common tumor for which calcitonin levels would be irrelevant.
Peter C. Butler et al. · Diabetes Care · 2013

Why this rating

Based on animal models, human histological data showing GLP-1 receptor expression, and FDA adverse event reporting, but conflicting epidemiological data.

Source

A Critical Analysis of the Clinical Use of Incretin-Based Therapies

Peter C. Butler et al. · Diabetes Care · 2013

DOI 10.2337/dc12-2713

narrative_reviewCited 294×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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