SARS-CoV-2 vaccination site as possible pitfall on somatostatin receptor imaging

Abstract

SARS-CoV-2 (COVID-19) vaccination numbers are globally increasing. Therefore, an increased chance exists that patients undergoing Peptide Receptor Radionuclide Therapy (PRRT) or diagnostic radionuclide imaging for Neuroendocrine Tumours (NETs) may have recently received vaccination. We report the imaging findings of two NETs patients, A—following [ 177 Lu] Lu-DOTATATE PRRT post therapy planar scintigraphy and single photon emission computed tomography with computed tomography (SPECT/CT), and B—following [ 68 Ga]Ga-DOTA-NOC positron emission tomography with computed tomography (PET/CT) respectively. Both studies were done few days after COVID-19 vaccination. Patient A showed a new focus of uptake in the left deltoid muscle; and Patient B showed uptake in the left deltoid and a left axillary lymph node. Nuclear Physicians need to be aware of pitfalls with somatostatin receptor radionuclide imaging post-vaccination to ensure accurate interpretation, as well as dosimetric considerations with vaccine-related post-therapy uptake.

[18F]FES PET Resolves the Diagnostic Dilemma of COVID-19-Vaccine-Associated Hypermetabolic Lymphadenopathy in ER-Positive Breast Cancer

“…Since their approval at the end of 2020, COVID-19 vaccines have been widely distributed worldwide, and reports on FDG PET findings after vaccine administration have been published since the first half of 2021 [2,[16][17][18]. Vaccine-induced accumulation in the ipsilateral axillary lymph nodes is known to be observed not only with FDG but also with [ 11 C] Choline [19], [ 18 F]Choline [20], [ 18 F] prostate-specific membrane antigen (PSMA) [20], [ 68 Ga]DOTA-peptide (DOTATATE) [21], and [ 177 Lu] Lu-DOTATATE PRRT post-therapy planar scintigraphy, as well as single-photon emission computed tomography with computed tomography (SPECT/CT) [22]. On the other hand, [ 68 Ga] fibroblast-activation protein inhibitor (FAPI) was reported to show no accumulation in the enlarged axillary lymph nodes after vaccine administration, similar to our report on [ 18 F]FES, which may be useful in distinguishing lymph node metastasis [23].…”