¹⁸F-FDG PET/CT Scans Reveal Vascular Inflammation From Pembrolizumab

Background: Pembrolizumab is an immune checkpoint inhibitor (ICI) often administered for treatment of malignancies. However, vascular side effects from these medications such as myocarditis, pericarditis, and vasculitis have been reported. Since 18 F-FDG PET/CT scans may be able to detect vascular inflammatory changes, identifying such changes in patients receiving pembrolizumab with this imaging approach might be valuable for patient management. Objective: To determine if subclinical arterial vasculitis in patients receiving pembrolizumab therapy can be detected on 18 F-FDG PET/CT scans. Methods: The clinical and imaging data on consecutive patients who were receiving pembrolizumab therapy between May 2016 and June 2023 were obtained. Inclusion in the study required that each patient had at least 4 doses of pembrolizumab and have 18 F-FDG PET/CT scans at baseline and after at least 4 doses of therapy. The 18 F-FDG PET/CT examinations were performed on either the Biograph or Biograph more...