Association of COVID-19 mRNA Vaccine With Ipsilateral Axillary Lymph Node Reactivity on Imaging

Research letter notes in this cohort (n=68), reactive ipsilateral axillary lymph nodes developed in 9 (13%) patients. It was less common after 1st vaccine dose than 2nd, and women were more likely to develop reactive nodes (n=7), an important implication for breast cancer imaging

SPS commentary:

The researchers highlight that intramuscular COVID-19 vaccinations could induce ipsilateral axillary lymph node reactivity that may be falsely attributed to malignant abnormality, prompting unwarranted interventions, or it may be falsely attributed to vaccination rather than cancer, potentially delaying cancer care.

JAMA Oncology