Computed Tomography Imaging of COVID-19 Vaccination–related Axillary Lymphadenopathy: Updated Review of Literature

Abstract

As of September 2022, approximately 606 million cases of COVID-19 have been reported and 6.5 million deaths have occurred worldwide [1]. COVID-19 vaccination programs are in progress around the world to control the pandemic [2]. Till September 2022 approximately 12.6 billion doses of the vaccine have been globally administered [3]. It has been found that reactive hyperplasia of the ipsilateral axillary nodes and sometimes contralateral node is a side effect of vaccination [4]. The frequency of imaging-detected lymphadenopathy ranged between 14.5 to 53% [5]. Cancer patients undergoing active treatment or follow-up surveillance undergo frequent cross-sectional imaging which incidentally detects vaccine-related lymphadenopathy. A Chest CT scan is the most used imaging modality for lung cancer monitoring and lung screening for metastasis of other malignancies. Thus, incidentally detected COVID-19-associated axillary lymph node enlargement is seen in these patients who undergo frequent chest CT scans including the axilla. It is difficult to differentiate lymph node enlargement due to Covid vaccination from lymph node metastasis on imaging. This can lead to unnecessary fine needle aspiration cytology or biopsy thus increasing the patient’s cost and public health burden [6][7][8]. This systematic review aims to evaluate the published literature evidence of axillary lymphadenopathy after COVID-19 vaccination and its imaging features on Chest CT.