Learning objectives
After reading this educational exhibit, the reader should:- be able to recognise typical appearances of benign reactive hyperplasia across multiple modalities.- be aware of other ancillary imaging findings of vaccine related unilateral axillary lymphadenopathy.- recognise the importance in obtaining an accurate vaccine history prior to any imaging of the axilla, especially during periods of mass vaccination and subsequent booster programmes.- recognise the importance of taking in to account the patient's risk factors for malignancy when determining subsequent management.
Background
The patients in this series were selected from two institutions in January and February 2021, shortly after the UK vaccination programme commenced. They include patients with a known malignancy as well as patients without a history of malignancy presenting to symptomatic breast clinic.
Findings and procedure details
Ultrasound offers the most thorough assessment of the size and morphology of axillary lymph nodes due to its high soft-tissue resolution. Sonographic changes seen in COVID-19 vaccine related adenopathy include lymph node enlargement, a thickened cortex and loss of the normal fatty hilum (Figure 1).
Similarly, on CT the nodes may be enlarged with thickened cortices and possibly with surrounding fat stranding (Figure 2).
A feature unique to MRI in determining vaccination as the cause of axillary adenopathy is high T2/STIR signal in the ipsilateral...
Conclusion
Unilateral axillary adenopathy is a commonly encountered side effect of COVID-19 vaccination and will be further encountered by radiologists during future COVID-19 booster vaccination programmes.
Imaging findings of reactive adenopathy are non-specific, usually consisting of lymph node enlargement and symmetrical cortical thickening. Therefore important consideration must be given to the patient's vaccine history and relevant cancer risk factors to determine appropriate follow up and management. Particular caution must be taken in patients with a history of breast cancer; there should be a low threshold for...
Personal information and conflict of interest
A. H. Brown:
Nothing to disclose
S. Shah:
Nothing to disclose
S. Dluzewski:
Nothing to disclose
B. Musaddaq:
Nothing to disclose
A. Malhotra:
Nothing to disclose
References
1. Wolfson et al. Axillary adenopathy after COVID-19 vaccine: No reason to delay screening mammogram. Radiology. 2022 Feb 8;213227. doi: 10.1148/radiol.213227