Lee H, Hwang KH. Unexpected focal fluorodeoxyglucose uptake in main organs; pass through or pass by? World J Clin Cases 2024; 12(11): 1885-1899 [PMID: 38660550 DOI: 10.12998/wjcc.v12.i11.1885]
Corresponding Author of This Article
Kyung-Hoon Hwang, MD, PhD, Professor, Department of Nuclear Medicine, Gachon University College of Medicine, Gil Medical Center, 21 Namdong-daero 774 Beon-gil, Namdong-gu, Incheon 21565, South Korea. forrest88@hanmail.net
Research Domain of This Article
Radiology, Nuclear Medicine & Medical Imaging
Article-Type of This Article
Review
Open-Access Policy of This Article
This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
World J Clin Cases. Apr 16, 2024; 12(11): 1885-1899 Published online Apr 16, 2024. doi: 10.12998/wjcc.v12.i11.1885
Unexpected focal fluorodeoxyglucose uptake in main organs; pass through or pass by?
Haejun Lee, Kyung-Hoon Hwang
Haejun Lee, Kyung-Hoon Hwang, Department of Nuclear Medicine, Gachon University College of Medicine, Gil Medical Center, Incheon 21565, South Korea
Author contributions: Lee H and Hwang KH contributed to this work, designed the editorial, searched the articles, analyzed the data, and wrote the manuscript; Lee H contributed analytic tools; all authors have read and approved the final manuscript.
Conflict-of-interest statement: The authors declare that they have no conflicting interests.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Kyung-Hoon Hwang, MD, PhD, Professor, Department of Nuclear Medicine, Gachon University College of Medicine, Gil Medical Center, 21 Namdong-daero 774 Beon-gil, Namdong-gu, Incheon 21565, South Korea. forrest88@hanmail.net
Received: December 30, 2023 Peer-review started: December 30, 2023 First decision: January 17, 2024 Revised: January 31, 2024 Accepted: March 21, 2024 Article in press: March 21, 2024 Published online: April 16, 2024 Processing time: 102 Days and 16.1 Hours
Abstract
Since the inception of fluorine-18 fluorodeoxyglucose (F-18 FDG), positron emission tomography/computed tomography (PET/CT) utilizing F-18 FDG has become widely accepted as a valuable imaging modality in the field of oncology, with global prevalence in clinical practice. Given that a single Torso PET/CT scan encompasses the anatomical region from the skull base to the upper thigh, the detection of incidental abnormal focal hypermetabolism in areas of limited clinical interest is both feasible and not uncommon. Numerous investigations have been undertaken to delineate the distinctive features of these findings, yet the outcomes have proven inconclusive. The incongruent results of these studies present a challenge for physicians, leaving them uncertain about the appropriate course of action. This article provides a succinct overview of the characteristics of fluorodeoxyglucose, followed by a comprehensive discussion of the imaging findings and clinical significance associated with incidental focal abnormal F-18 FDG activity in several representative organs. In conclusion, while the prevalence of unrecognized malignancy varies across organs, malignancies account for a substantial proportion, ranging from approximately one-third to over half, of incidental focal uptake. In light of these rates, physicians are urged to exercise vigilance in not disregarding unexpected uptake, facilitating more assured clinical decisions, and advocating for further active evaluation.
Core Tip: Unexpected incidental focal fluorine-18 fluorodeoxyglucose uptake on positron emission tomography/computed tomography is not an uncommon finding. The nature of this uptake has been the subject of various studies, with outcomes varying depending on the organ in which it manifests. A noteworthy finding from these investigations reveals that over one-third of such uptakes were determined to be malignant. This observation underscores the importance of conducting further examinations in cases where incidental uptake is identified, as it could potentially serve as a crucial indicator for malignancy.
