Skip to main content

Main menu

  • Home
  • Content
    • Current
      • JNMT Supplement
    • Ahead of print
    • Past Issues
    • Continuing Education
    • JNMT Podcast
    • SNMMI Annual Meeting Abstracts
  • Subscriptions
    • Subscribers
    • Rates
    • Journal Claims
    • Institutional and Non-member
  • Authors
    • Submit to JNMT
    • Information for Authors
    • Assignment of Copyright
    • AQARA Requirements
  • Info
    • Reviewers
    • Permissions
    • Advertisers
    • Corporate & Special Sales
  • About
    • About Us
    • Editorial Board
    • Contact Information
  • More
    • Alerts
    • Feedback
    • Help
    • SNMMI Journals
  • SNMMI
    • JNMT
    • JNM
    • SNMMI Journals
    • SNMMI

User menu

  • Subscribe
  • My alerts
  • Log in
  • Log out
  • My Cart

Search

  • Advanced search
Journal of Nuclear Medicine Technology
  • SNMMI
    • JNMT
    • JNM
    • SNMMI Journals
    • SNMMI
  • Subscribe
  • My alerts
  • Log in
  • Log out
  • My Cart
Journal of Nuclear Medicine Technology

Advanced Search

  • Home
  • Content
    • Current
    • Ahead of print
    • Past Issues
    • Continuing Education
    • JNMT Podcast
    • SNMMI Annual Meeting Abstracts
  • Subscriptions
    • Subscribers
    • Rates
    • Journal Claims
    • Institutional and Non-member
  • Authors
    • Submit to JNMT
    • Information for Authors
    • Assignment of Copyright
    • AQARA Requirements
  • Info
    • Reviewers
    • Permissions
    • Advertisers
    • Corporate & Special Sales
  • About
    • About Us
    • Editorial Board
    • Contact Information
  • More
    • Alerts
    • Feedback
    • Help
    • SNMMI Journals
  • Watch or Listen to JNMT Podcast
  • Visit SNMMI on Facebook
  • Join SNMMI on LinkedIn
  • Follow SNMMI on Twitter
  • Subscribe to JNMT RSS feeds
Research ArticleTeaching Case Studies

Reactive Axillary Lymphadenopathy to COVID-19 Vaccination on 18F-FDG PET/CT

Mathew V. Smith and Ming Yang
Journal of Nuclear Medicine Technology September 2021, 49 (3) 286-287; DOI: https://doi.org/10.2967/jnmt.121.262008
Mathew V. Smith
Department of Radiology, Mayo Clinic, Scottsdale, Arizona
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Ming Yang
Department of Radiology, Mayo Clinic, Scottsdale, Arizona
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • Article
  • Figures & Data
  • Info & Metrics
  • PDF
Loading

Abstract

In this report, we present 18F-FDG PET/CT findings of reactive left axillary and supraclavicular hypermetabolic lymphadenopathy, as well as ipsilateral deltoid muscle injection site radiotracer uptake, related to recent coronavirus disease 2019 (COVID-19) vaccination in a patient with osteosarcoma. With the growing number of patients receiving COVID-19 vaccine, recognition of benign characteristic 18F-FDG PET/CT image findings will ensure staging and restaging accuracy and avoid unnecessary biopsy.

  • COVID-19
  • vaccination
  • lymphadenopathy

Reactive lymphadenopathy is a recognized side effect related to vaccination. With messenger RNA–based coronavirus disease 2019 (COVID-19) vaccines, efficacy depends on the activation of dendritic cells after administration. These activated antigen-presenting cells must then migrate to the draining lymph nodes and present the translated protein to the node-based B and T cells in order to create robust humoral and cell-mediated adaptive immunity (1). As more oncologic patients start to receive COVID-19 vaccines, it is important to recognize the benign 18F-FDG PET/CT imaging features immediately after vaccination to ensure staging accuracy and prevent unnecessary biopsy.

CASE REPORT

A 40-y-old woman with a history of metastatic left proximal tibia osteosarcoma underwent surveillant 18F-FDG PET/CT. There was no radiotracer uptake suggestive of tumor recurrence. However, multiple morphologically benign-appearing hypermetabolic lymph nodes were visualized at the left axillary and supraclavicular regions, as well as focal uptake in the left deltoid muscle (Fig. 1). On further interview, the patient revealed receiving her second dose of the BNT162b2 vaccine (Pfizer/BioNTech) against SARS-CoV-2 the day before the 18F-FDG PET/CT scan. She also stated that she had experienced pain at the left-upper-arm injection site, intense body aches, headaches, and a slight fever. Combined with inoculation history and characteristic imaging features, as well as exclusion of tracer injection at ipsilateral arm, a diagnosis of reactive lymphadenopathy secondary to COVID-19 vaccination was achieved.

FIGURE 1.
  • Download figure
  • Open in new tab
  • Download powerpoint
FIGURE 1.

(A) Maximum-intensity-projection image demonstrating cluster of hypermetabolic left axillary lymph nodes (encircled), cluster of hypermetabolic supraclavicular lymph nodes (arrow), and faint intramuscular radiotracer uptake (star). (B and C) Representative left axillary lymph node that appears benign on axial CT image (C) but demonstrates increased uptake (SUVmax, 7.1) on axial 18F-FDG PET/CT image (B).

Reactive lymphadenopathy is one of the well-documented reactions after intramuscular injection of COVID-19 vaccine and is likely secondary to a robust vaccine-elicited immune response (2,3). The efficacy of messenger RNA COVID-19 vaccine depends on encoding dendritic cell migration to draining lymph nodes in order to kickstart the complex humoral and cell-mediated response and, ultimately, to establish immunity (2). There are rich draining lymph nodes at the axillary region that may show an immediate response after vaccination (4,5). 18F-FDG is a glucose analog and is nonspecifically trapped in metabolically active tumor cells and benign conditions such as infection and inflammation, potentially leading to false-positive interpretations on oncologic 18F-FDG PET/CT scans (6). Among the most common etiologies of hypermetabolic axillary lymph nodes on 18F-FDG PET/CT scans are malignancies, reactive changes, and lymphatic drainage of radiotracer extravasation.

CONCLUSION

With more oncologic patients receiving messenger RNA COVID-19 vaccines, it is important for nuclear radiologists to recognize the characteristic benign 18F-FDG uptake after vaccination. A detailed COVID-19 vaccination history, including the inoculation time, which arm was injected, and any side effects, should be acquired before the 18F-FDG PET/CT scan to ensure the accuracy of staging or restaging and to avoid an unnecessary biopsy.

DISCLOSURE

No potential conflict of interest relevant to this article was reported.

Footnotes

  • Published online April 5, 2021.

REFERENCES

  1. 1.↵
    1. Lindsay KE,
    2. Bhosle SM,
    3. Zurla C,
    4. et al
    . Visualization of early events in mRNA vaccine delivery in non-human primates via PET-CT and near-infrared imaging. Nat Biomed Eng. 2019;3:371–380.
    OpenUrl
  2. 2.↵
    1. Polack FP,
    2. Thomas SJ,
    3. Kitchin N,
    4. et al
    . Safety and efficacy of the BNT162b2 MRNA Covid-19 vaccine. N Engl J Med. 2020;383:2603–2615.
    OpenUrlCrossRefPubMed
  3. 3.↵
    1. Baden LR,
    2. El Sahly HM,
    3. Essink B,
    4. et al
    . Efficacy and safety of the mRNA-1273 SARS-CoV-2 vaccine. N Engl J Med. 2021;384:403–416.
    OpenUrlCrossRefPubMed
  4. 4.↵
    1. Coates EE,
    2. Costner PJ,
    3. Nason MC,
    4. et al
    . Lymph node activation by PET/CT following vaccination with licensed vaccines for human papillomaviruses. Clin Nucl Med. 2017;42:329–334.
    OpenUrl
  5. 5.↵
    1. Thomassen A,
    2. Lerberg Nielsen A,
    3. Gerke O,
    4. Johansen A,
    5. Petersen H.
    Duration of 18F-FDG avidity in lymph nodes after pandemic H1N1v and seasonal influenza vaccination. Eur J Nucl Med Mol Imaging. 2011;38:894–898.
    OpenUrlCrossRefPubMed
  6. 6.↵
    1. Stumpe KD,
    2. Dazzi H,
    3. Schaffner A,
    4. von Schulthess GK.
    Infection imaging using whole-body FDG-PET. Eur J Nucl Med. 2000;27:822–832.
    OpenUrlCrossRefPubMed
  • Received for publication January 26, 2021.
  • Accepted for publication March 9, 2021.
PreviousNext
Back to top

In this issue

Journal of Nuclear Medicine Technology: 49 (3)
Journal of Nuclear Medicine Technology
Vol. 49, Issue 3
September 1, 2021
  • Table of Contents
  • About the Cover
  • Index by author
  • Complete Issue (PDF)
Print
Download PDF
Article Alerts
Sign In to Email Alerts with your Email Address
Email Article

Thank you for your interest in spreading the word on Journal of Nuclear Medicine Technology.

NOTE: We only request your email address so that the person you are recommending the page to knows that you wanted them to see it, and that it is not junk mail. We do not capture any email address.

Enter multiple addresses on separate lines or separate them with commas.
Reactive Axillary Lymphadenopathy to COVID-19 Vaccination on 18F-FDG PET/CT
(Your Name) has sent you a message from Journal of Nuclear Medicine Technology
(Your Name) thought you would like to see the Journal of Nuclear Medicine Technology web site.
Citation Tools
Reactive Axillary Lymphadenopathy to COVID-19 Vaccination on 18F-FDG PET/CT
Mathew V. Smith, Ming Yang
Journal of Nuclear Medicine Technology Sep 2021, 49 (3) 286-287; DOI: 10.2967/jnmt.121.262008

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero
Share
Reactive Axillary Lymphadenopathy to COVID-19 Vaccination on 18F-FDG PET/CT
Mathew V. Smith, Ming Yang
Journal of Nuclear Medicine Technology Sep 2021, 49 (3) 286-287; DOI: 10.2967/jnmt.121.262008
Twitter logo Facebook logo LinkedIn logo Mendeley logo
  • Tweet Widget
  • Facebook Like
  • Google Plus One
Bookmark this article

Jump to section

  • Article
    • Abstract
    • CASE REPORT
    • CONCLUSION
    • DISCLOSURE
    • Footnotes
    • REFERENCES
  • Figures & Data
  • Info & Metrics
  • PDF

Related Articles

  • No related articles found.
  • PubMed
  • Google Scholar

Cited By...

  • A Quick Guide to Writing a Teaching Case Study
  • Once Again--The SNMMI "Nailed It"!
  • Google Scholar

More in this TOC Section

  • High-Sensitivity Troponin Elevation in a Young Woman with Typical Chest Pain: The Heart of the Matter
  • Pulmonary Adenocarcinoma Revealed by Parathyroid Scintigraphy: An Incidental Case to Remember
  • Prominent Right Ventricular Tracer Uptake: A Harbinger of Multivessel Coronary Artery Disease
Show more Teaching Case Studies

Similar Articles

Keywords

  • COVID-19
  • vaccination
  • lymphadenopathy
SNMMI

© 2025 SNMMI

Powered by HighWire