Prevalence of increased fdg pet/ct axillary lymph node uptake beyond 6 weeks after mrna covid-19 vaccination

Abstract

This study shows that avid axillary lymph node uptake at FDG PET/CT can be detected in more than a quarter of our patient population even beyond 6 weeks after the second dose of the mRNA-based COVID-19 vaccination. Compared with a previous study showing normalization of FDG uptake within 40 days of receiving an inactivated H1N1 influenza vaccine (6), we found uptake persistence even at 70 days. Physicians should be aware of this potential pitfall.