A sigh of relief: vaccine-associated hypermetabolic lymphadenopathy following the third COVID-19 vaccine dose is short in duration and uncommonly interferes with the interpretation of [18F]FDG PET-CT studies performed in oncologic patients.

VAHL is commonly identified on [18F]FDG PET-CT performed within the first 5 days from the third BNT162b2 vaccine dose administration. High-grade VAHL is unlikely to be observed on a scan performed 6 days or longer from vaccination, and is even less likely in older and obese patients.