Lymphadenopathy after COVID-19 vaccination in patients with endocrine cancer: two case reports.

Reactive lymphadenopathy is very common after an mRNA vaccination against Covid-19 and should be part of the differential diagnosis in patients with endocrine tumours who recently received a Covid-19 mRNA vaccination and present with an ipsilateral lymphadenopathy. A good vaccine history is essential in assessing the risk for lymphadenopathy and if possible, screening imaging in patients with endocrine tumours should be postponed at least 6 weeks after the previous vaccination. For now, a multidisciplinary care approach is recommended to determine the necessary steps in the diagnostic evaluation of lymphadenopathy in the proximity of a Covid-19 vaccination.