COVID-19 vaccine associated cervical lymphadenopathy: a case series

COVID-19 is an evolving worldwide pandemic causing significant morbidity and mortality. COVID-19 vaccinations have been developed to increase immunity against the virus. In New Zealand, the Pfizer BioNTech mRNA vaccine has been provisionally approved for use. Axillary lymphadenopathy is a recognized side effect of the mRNA vaccine, however cervical lymphadenopathy has also been reported. Due to a wide range of differential diagnoses, the finding of cervical lymphadenopathy requires thorough investigation which can include imaging and invasive diagnostic procedures.

Five patients were identified by otorhinolaryngology (ORL) consultants at Whangarei Base Hospital and Waikato Hospital between 15/7/2021 and 21/12/2021 after being investigated through high suspicion of cancer triage pathways set by the New Zealand Ministry of Health. Inclusion criteria were adult patients with cervical lymphadenopathy following vaccination. Exclusion criteria were no history of vaccination or lymphadenopathy present before vaccination.

All patients were identified to have cervical lymphadenopathy on radiological imaging and a recent history of COVID-19 vaccination with the Pfizer BioNTech vaccine. Interval vaccination to fine needle aspiration time ranged between 41 and 76 days. All patients had cytological or histological diagnosis showing reactive findings or interval imaging showing resolution of lymphadenopathy.

With increasing levels of COVID-19 vaccination and booster vaccinations we will continue to see cases of COVID-19 vaccine associated cervical lymphadenopathy. We highlight the importance of taking a COVID-19 vaccination history and including COVID-19 associated cervical lymphadenopathy in the differential diagnosis of presentation with a neck lump.