FDG PET/CT Images Demonstrating Subclinical Pancreatitis in a Patient on a GLP-1 Receptor Agonist

An 83-year-old man with basal cell carcinoma was referred for an 18 F-FDG PET/CT scan for staging. The FDG PET/CT scan revealed diffuse increased radiotracer uptake within the pancreas without CT abnormality, which raised concern for pancreatitis. Although this man was clinically asymptomatic, a lipase level obtained after the PET/CT scan was elevated, confirming the diagnosis. This man was noted to be on tirzepatide, which is a GLP-1 receptor agonist medication used for type 2 diabetes and weight loss. No other causes of pancreatitis were identified in this man, and therefore, the cause was attributed to this medication.