Prevalence and Significance of Hypermetabolic Lymph Nodes Detected by 2-[¹⁸F]FDG PET/CT after COVID-19 Vaccination: A Systematic Review and a Meta-Analysis

• Main Authors: Giorgio Treglia (Author), Marco Cuzzocrea (Author), Luca Giovanella (Author), Luigia Elzi (Author), Barbara Muoio (Author)
• Format: Book
• Published: MDPI AG, 2021-08-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.
• Notes: 10.3390/ph14080762; 1424-8247
• Keywords: COVID-19; vaccine; PET; FDG; lymph nodes; inflammation; Medicine; R; Pharmacy and materia medica; RS1-441
• Source: Pharmaceuticals, Vol 14, Iss 8, p 762 (2021)

Recently, several articles reported incidental findings at 2-[¹⁸F]FDG PET/CT in patients who have received COVID-19 vaccinations, including hypermetabolic axillary lymph nodes (HALNs) ipsilateral to the COVID-19 vaccine injection site which may cause diagnostic dilemmas. The aim of our work was to calculate the prevalence of this finding. A comprehensive computer literature search of PubMed/MEDLINE, Embase, and Cochrane library databases was performed to identify recently published articles that investigated the prevalence of HALNs detected by 2-[¹⁸F]FDG PET/CT after COVID-19 vaccination. Pooled prevalence of this finding was calculated through a meta-analytic approach. Nine recently published articles including 2354 patients undergoing 2-[¹⁸F]FDG PET/CT after recent COVID-19 vaccination have been included in the systematic review. Overall, HALNs ipsilateral to the vaccine injection site were frequent findings mainly due to vaccine-related immune response in most of the cases. The pooled prevalence of HALNs after COVID-19 vaccination was 37% (95% confidence interval: 27-47%) but with significant heterogeneity among the included studies. Physicians must be aware and recognize the significant frequency of HALNs at 2-[¹⁸F]FDG PET/CT related to immune response to vaccine injection. Larger studies are needed to confirm the findings of this systematic review and meta-analysis.