Axillary node reactivity after mRNA vaccine ‘can mimic malignancy’

Ipsilateral axillary lymph node reactivity seen in one in four patients after the IM administration of a COVID-19 mRNA vaccine may cause unnecessary concern for cancer patients, a small study suggests.
Researchers from Yale School of Medicine examined 18F-fluorodeoxyglucose PET and CT scans of 68 patients who had had at least one vaccine dose of the Moderna or Pfizer-BioNTech COVID-19 vaccines.
All but one of the recipients had undergone the PET/CT for cancer indications, none of which was adenopathy ipsilateral to the vaccination site, the doctors wrote in a research letter to JAMA Oncology.
Reactive ipsilateral axillary lymph nodes developed in nine patients, seven of whom were women.