Ipsilateral Lymphadenopathy, COVID-19 Vaccination and Breast Cancer.

Dear Editor,

We would like to correspond and share ideas on the publication “Ipsilateral Lymphadenopathy After COVID-19 Vaccination in Patients With Newly Diagnosed Breast Cancer [1].”

Abnormal US and MRI findings of cortical thickening, effacement of the fatty hilum, round form, and asymmetry in the number or size relative to the contralateral side were observed in more than half of non-metastatic and metastatic lymph nodes, according to Ha et al. [1]. Ha and colleagues [1] also noted that axillary lymphadenopathy was typically reported in breast cancer patients who got concurrent ipsilateral COVID-19 vaccination without distinct differential imaging findings. We agree that interpreting lymphadenopathy from an imaging investigation in a COVID-19 vaccination recipient is sometimes problematic.

Ha et al. [1] stated that there should be no excessive unnecessary investigation, but did not offer any specific suggestions for how to handle the situation. In general, it is recommended that imaging should be avoided for the first 10 weeks after vaccination [2].

Additionally, Ha et al. [1] attempted to link pathological and imaging findings in their investigation. If there is additional information on vaccination timing, a study of the relationship between lymphadenopathy features and the time between immunization and imaging could be assessed.