Thyroid lesions incidentally detected by 18F-FDG PET-CT ― a two centre retrospective study

AbstractBackground. Incidental18F-FDG uptake in the thyroid on PET-CT examinations represents a diagnostic challenge. The maximal standardized uptake value (SUVmax) is one possible parameter that can help in distinguishing between benign and malignant thyroid PET lesions.Patients and methods. We retrospectively evaluated18F-FDG PET-CT examinations of 5,911 patients performed at two different medical centres from 2010 to 2011. If pathologically increased activity was accidentally detected in the thyroid, the SUVmaxof the thyroid lesion was calculated. Patients with incidental18F-FDG uptake in the thyroid were instructed to visit a thyroidologist, who performed further investigation including fine needle aspiration cytology (FNAC) if needed. Lesions deemed suspicious after FNAC were referred for surgery.Results. Incidental18F-FDG uptake in the thyroid was found in 3.89% ― in 230 out of 5,911 patients investigated on PET-CT. Malignant thyroid lesions (represented with focal thyroid uptake) were detected in 10 of 66 patients (in 15.2%). In the first medical centre the SUVmaxof 36 benign lesions was 5.6 ± 2.8 compared to 15.8 ± 9.2 of 5 malignant lesions (p < 0.001). In the second centre the SUVmaxof 20 benign lesions was 3.7 ± 2.2 compared to 5.1 ± 2.3 of 5 malignant lesions (p = 0.217). All 29 further investigated diffuse thyroid lesions were benign.Conclusions. Incidental18F-FDG uptake in the thyroid was found in 3.89% of patients who had a PET-CT examination. Only focal thyroid uptake represented a malignant lesion in our study ― in 15.2% of all focal thyroid lesions. SUVmaxshould only serve as one of several parameters that alert the clinician on the possibility of thyroid malignancy.

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Pulmonary Findings of [18F]FDG PET/CT Images on Asymptomatic COVID-19 Patients

Pathogens ◽

10.3390/pathogens10070839 ◽

2021 ◽

Vol 10 (7) ◽

pp. 839

Author(s):

Tzu-Chuan Ho ◽

Chin-Chuan Chang ◽

Hung-Pin Chan ◽

Ying-Fong Huang ◽

Yi-Ming Arthur Chen ◽

...

Keyword(s):

Systematic Review ◽

Fdg Pet ◽

Standardized Uptake Value ◽

Fdg Uptake ◽

Asymptomatic Patients ◽

Positron Emission ◽

Pet Ct ◽

18F Fdg ◽

Maximal Standardized Uptake Value ◽

Fdg Pet Ct

During the coronavirus disease 2019 (COVID-19) pandemic, several case studies demonstrated that many asymptomatic patients with COVID-19 underwent fluorine-18 fluorodeoxyglucose ([18F]FDG) positron emission tomography/computed tomography (PET/CT) examination for various indications. However, there is a lack of literature to characterize the pattern of [18F]FDG PET/CT imaging on asymptomatic COVID-19 patients. Therefore, a systematic review to analyze the pulmonary findings of [18F]FDG PET/CT on asymptomatic COVID-19 patients was conducted. This systematic review was performed under the guidelines of PRISMA. PubMed, Medline, and Web of Science were used to search for articles for this review. Articles with the key words: “asymptomatic”, “COVID-19”, “[18F]FDG PET/CT”, and “nuclear medicine” were searched for from 1 January 2020 to 20 May 2021. Thirty asymptomatic patients with COVID-19 were included in the eighteen articles. These patients had a mean age of 62.25 ± 14.85 years (male: 67.71 ± 12.00; female: 56.79 ± 15.81). [18F]FDG-avid lung lesions were found in 93.33% (28/30) of total patients. The major lesion was [18F]FDG-avid multiple ground-glass opacities (GGOs) in the peripheral or subpleural region in bilateral lungs, followed by the consolidation. The intensity of [18F]FDG uptake in multiple GGOs was 5.605 ± 2.914 (range from 2 to 12) for maximal standardized uptake value (SUVmax). [18F]FDG-avid thoracic lymph nodes (LN) were observed in 40% (12/40) of the patients. They mostly appeared in both mediastinal and hilar regions with an SUVmax of 5.8 ± 2.93 (range from 2.5 to 9.6). The [18F]FDG uptake was observed in multiple GGOs, as well as in the mediastinal and hilar LNs. These are common patterns in PET/CT of asymptomatic patients with COVID-19.

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Comparison of MR imaging and FDG-PET/CT in the differential diagnosis of benign and malignant vertebral compression fractures

Journal of Neurosurgery Spine ◽

10.3171/2010.10.spine10175 ◽

2011 ◽

Vol 14 (2) ◽

pp. 177-183 ◽

Cited By ~ 16

Author(s):

Won-Ik Cho ◽

Ung-Kyu Chang

Keyword(s):

Mr Imaging ◽

Fdg Pet ◽

Vertebral Compression Fractures ◽

Benign Lesions ◽

Fracture Group ◽

Radiotracer Uptake ◽

Pet Ct ◽

Malignant Lesions ◽

Fdg Pet Ct ◽

Mass Formation

Object Differentiation between malignant and benign vertebral compression fractures (VCFs) is important but sometimes difficult, especially in elderly cancer patients. The authors investigated the findings of MR imaging and FDG-PET/CT for the differentiation of VCFs. Methods Between 2007 and 2008, the authors evaluated and treated 102 VCFs in 96 patients. The final diagnosis, based on biopsy results or clinical follow-up, was benign fracture in 67 lesions in 65 patients and malignant fracture in 35 lesions in 31 patients. Magnetic resonance images were obtained in all patients, and FDG-PET/CT was performed in 17 patients in the benign fracture group and 20 in the malignant fracture group. The prevalence of 3 significant MR imaging findings (posterior cortical bulging, epidural mass formation, and pedicle enhancement) and the presence of radiotracer uptake on FDG-PET/CT were evaluated in the 2 groups. The maximum standardized uptake value (SUVmax) on FDG-PET/CT was compared between the 2 groups, and diagnostic threshold value was sought to confirm malignancy. The diagnostic accuracy of MR imaging and FDG-PET/CT was compared in the differentiation of malignant from benign VCFs. Results Posterior cortical bulging was seen in 26 (74%) of 35 malignant lesions and 30 (45%) of 67 benign ones, epidural mass formation in 27 (77%) of the malignant lesions and 25% of the benign ones, and pedicle enhancement in 30 (91%) of the 33 malignant lesions and 18 (39%) of the 46 benign ones evaluated with Gd-enhanced MR imaging. These differences were statistically significant for each feature. Sensitivity and specificity for predicting malignancy were, respectively, 74% and 55% for posterior cortical bulging, 77% and 74% for epidural mass formation, and 90% and 61% for pedicle enhancement. Simultaneous occurrence of 3 significant features was found in 21 (64%) of the 33 malignant and 8 (17%) of the 46 benign lesions for which complete MR imaging data were available and showed sensitivity of 64% and specificity of 83%. The presence of radiotracer uptake on FDG-PET/CT was seen in all 20 (100%) of the 20 malignant lesions and 12 (71%) 17 of the benign lesions evaluated by FDG-PET/CT and showed a sensitivity of 100% and specificity of 29%. There was a significant difference in mean (± SD) SUVmax for the malignant (6.29 ± 3.50) and benign (2.38 ± 1.90) lesions (p < 0.001). The most reliable threshold for SUVmax was found to be 4.25, which yielded a sensitivity of 85% and a specificity of 71%. Conclusions When MR imaging findings are equivocal, FDG-PET/CT can be considered as an adjunctive diagnostic method for differentiating malignant from benign VCFs. In comparison with MR imaging, FDG-PET/CT showed slightly higher sensitivity and lower specificity.

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Use of 68Ga-PSMA-11 and 18F-FDG PET-CT Dual-Tracer to Differentiate Between Lymph Node Metastases and Ganglia

Frontiers in Oncology ◽

10.3389/fonc.2021.646110 ◽

2021 ◽

Vol 11 ◽

Author(s):

Yiping Shi ◽

Lian Xu ◽

Yinjie Zhu ◽

Yining Wang ◽

Ruohua Chen ◽

...

Keyword(s):

Lymph Node ◽

Lymph Node Metastases ◽

Fdg Pet ◽

Standardized Uptake Value ◽

Fdg Uptake ◽

Positron Emission ◽

Pet Ct ◽

Node Metastases ◽

Ct Data ◽

Fdg Pet Ct

PurposeDifferentiating lymph node metastases (LNM) from peripheral ganglia by physiological prostate-specific membrane antigen (PSMA) uptake is challenging. Two tracers (68Ga-PSMA-11 and 18F-fluorodeoxyglucose [FDG]) metabolic uptake patterns were evaluated by positron emission tomography-computed tomography (PET-CT), searching for differences that could tell ganglia from LNM.MethodsDual 68Ga-PSMA-11 and 18F-FDG PET-CT data of 138 prostate cancer patients acquired from June 2018 to December 2019 were retrospectively evaluated. Ganglia and LNM with PSMA-11 uptake above local background were analyzed by the location and PSMA-11-PET and FDG-PET maximum standardized uptake value (SUVmax).ResultsPSMA-11-positive ganglia (n = 381) and LNM (n = 83) were identified in 138 and 58 patients, respectively. The LNM SUVmax of PSMA-11-PET (16.4 ± 14.8 vs 2.3 ± 0.7, P < 0.001) and FDG-PET (3.3 ± 3.2 vs 1.5 ± 0.5, P < 0.001) were higher than in ganglia. The probabilities of being an LNM in the low-potential (PSMA-11-PET SUVmax of <4.1 and FDG-PET SUVmax of <2.05), moderate-potential (PSMA-11-PET SUVmax of >4.1 and FDG-PET SUVmax of <2.05, or PSMA-11-PET SUVmax of <4.1 and FDG-PET SUVmax of >2.05), and high-potential (PSMA-11-PET SUVmax of >4.1 and FDG-PET SUVmax of >2.05) groups were 0.9% (3/334), 44.6% (37/83), and 91.5% (43/47), respectively (P < 0.001). The cervical and coeliac ganglia had higher PSMA-11 and FDG uptake than the sacral ganglia (P < 0.001 for all). LNM PSMA-11 and FDG uptake was similar in these three locations.ConclusionThe FDG-PET and PSMA-11-PET SUVmax, especially when combined, could well differentiate LNM from ganglia. The tracers uptake differed between cervical/coeliac and sacral ganglia, so the lesion location should be considered during image assessment.

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The clinical impact of incidental sellar uptake on F-18 FDG PET/CT

International Journal of Endocrine Oncology ◽

10.2217/ije-2018-0004 ◽

2019 ◽

Vol 6 (2) ◽

pp. IJE15

Author(s):

Zehra Pınar Koç ◽

Pelin Özcan Kara ◽

Emel Sezer ◽

Kadir Eser ◽

Anıl Özgür

Keyword(s):

Fdg Pet ◽

Standardized Uptake Value ◽

Sellar Region ◽

Primary Tumors ◽

Fdg Uptake ◽

Pet Ct ◽

Frequent Finding ◽

Metastatic Involvement ◽

Fdg Pet Ct

Aim: The most frequent finding associated with incidental fluorodeoxyglucose (FDG) uptake in sellar region in oncologic F-18 FDG PET/CT is adenoma. However, reports of metastatic involvement exist. We investigated the clinical significance of incidental FDG uptake in this region. Materials & method: 34 patients with several primary tumors who were referred for staging, restaging or treatment response via F-18 FDG PET/CT were included. Images were reviewed and patients with significant FDG uptake in the sellar region were referred. Results: Mean lesion diameter was 11.9 ± 4.9 mm and mean standardized uptake value was 8.2 ± 6.1. Thirteen patients underwent MRI, and the others underwent follow-up F-18 FDG PET/CT. MRI revealed metastatic involvement in nine patients and macro- or micro-adenoma in four. Metastatic patients also had other lesions, yet management did not change. Conclusion: FDG accumulation in the sellar region might be associated with metastasis or adenoma. However, it did not change management. Future studies are warranted.

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PET/CT Parameters are Useful in Discrimination of Incidental Benign, Premalignant and Malignant Colonic Lesions

Nuklearmedizin ◽

10.1055/a-1084-4723 ◽

2020 ◽

Vol 59 (03) ◽

pp. 235-240

Author(s):

Emine Budak ◽

Ahmet Yanarateş

Keyword(s):

Tumor Volume ◽

Standardized Uptake Value ◽

Metabolic Tumor Volume ◽

Total Lesion Glycolysis ◽

Premalignant Lesions ◽

Benign Lesions ◽

Pet Ct ◽

Malignant Lesions ◽

Fdg Pet Ct

Abstract Aim The present study evaluates the role of PET parameters pertaining to incidentally detected foci of colorectal uptake (IFCU) on FDG PET/CT in the differentiation of benign, premalignant and malignant lesions. Methods This retrospective study included 74 patients. The colonoscopic and histopathological findings were regarded as the reference standards. The results were evaluated on a lesion basis by dividing the lesions into three groups as benign, premalignant and malignant. The maximum standardized uptake value (SUVmax), SUVmean, metabolic tumor volume(MTV) and total lesion glycolysis(TLG) values of the three groups were compared. Results There were 88 IFCU in a total of 74 patients (27 female, 47 male, mean age 65 years). Of the 88 IFCU, 26 were qualified as benign, 42 as premalignant and 20 as malignant. Malignant + premalignant lesions were found in 62/88 (70.4 %) of the IFCU. The SUVmax of the benign lesions was significantly lower than those of the premalignant and malignant lesions; and SUVmean was lower than that of the malignant lesions. The MTV of the malignant lesions was significantly higher than that of the premalignant and benign lesions; and TLG was higher than that of the premalignant lesions. The optimum cut-off value in differentiating between the malignant and non-malignant lesions was 9.15 for SUVmax, 5.05 for SUVmean, 4.7 for MTV and 30.25 for TLG. Conclusion PET parameters can guide the differentiation of benign, premalignant and malignant lesions with IFCU. Besides, patients with IFCU should undergo further evaluation due to high probability of premalignant and malignant lesions.

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The Usefulness of Standardized Uptake Value in Differentiation between Benign and Malignant Thyroid Lesions Detected Incidentally in 18F-FDG PET/CT Examination

PLoS ONE ◽

10.1371/journal.pone.0109612 ◽

2014 ◽

Vol 9 (10) ◽

pp. e109612 ◽

Cited By ~ 14

Author(s):

Adam Stangierski ◽

Kosma Woliński ◽

Rafał Czepczyński ◽

Agata Czarnywojtek ◽

Martha Lodyga ◽

...

Keyword(s):

Fdg Pet ◽

Standardized Uptake Value ◽

Ct Examination ◽

Pet Ct ◽

18F Fdg ◽

Fdg Pet Ct ◽

Thyroid Lesions

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The retention index calculated with dual-phase 18F-FDG PET/CT in ovarian carcinoma: Determination of the optimal cutoff level using ROC analysis.

Journal of Clinical Oncology ◽

10.1200/jco.2013.31.15_suppl.5539 ◽

2013 ◽

Vol 31 (15_suppl) ◽

pp. 5539-5539

Author(s):

Jin Hwa Hong ◽

Sungeun Kim ◽

Kyung Jin Min ◽

Kyeong A So ◽

Jae Kwan Lee

Keyword(s):

Retention Index ◽

Roc Curve ◽

Fdg Pet ◽

Standardized Uptake Value ◽

Preoperative Imaging ◽

Dual Phase ◽

Benign Lesions ◽

Ovarian Cancers ◽

Pet Ct ◽

Fdg Pet Ct

5539 Background: Although 18F-fluorodeoxyglucose (FDG) positron emission tomography /computed tomography (PET/CT) is useful as a clinical tool in various malignancies, the maximum standardized uptake value (SUVmax) overlap between malignant and benign lesions is significant. The dual-phase PET/CT has shown its usefulness to differentiate benign from malignant conditions in some solid tumors, but its usefulness has not yet been evaluated in patients with ovarian cancers. Methods: Twenty consecutive patients (thirteen with ovarian cancers and seven with benign lesions) were evaluated preoperatively by dual-phase 18F-FDG PET/CT (Time of Flight, Philips), performed 1 and 2 hour after injection of 370-555 MBq of 18F-FDG. The SUVmax at 1 hour (SUVmax1) and at 2 hour (SUVmax2) were determined, and the retention index (RI) was calculated by subtracting the SUVmax1 from the SUVmax2 and dividing by SUVmax1. Results: Area under the receiver operating characteristic (ROC) curve of SUVmax1 and SUVmax2 were 0.753 and 0.835, respectively (95% CI; 0.512, 0.915 versus 0.604, 0.961; p = 0.062 versus 0.001). Area under the ROC curve of RI was 0.901 (95% CI; 0.684, 0.988; p <0.001). When the SUVmax1 cutoff was set to 3.2, the sensitivity and the specificity of the SUVmax1 were 100% and 57.1%, respectively. When the SUVmax2 cutoff was set to 3.9, the sensitivity and the specificity of the SUVmax2 were 100% and 57.1%, respectively. The sensitivity and the specificity of RI were 92.3% and 71.4% when the cutoff was set to 16.67. By pairwise comparisons, the area under the ROC curve of SUVmax2 was significantly higher than that of SUVmax1 (p = 0.032). The area under the ROC curve of the RI was higher than those of SUVmax1 and SUVmax2, but not statistically significant (p = 0.166 and 0.459, respectively). Conclusions: The RI and SUVmax2 are proved to be useful in differentiating ovarian cancers from benign lesions. The use of dual-phase 18F-FDG PET/CT should be taken into account when the preoperative imaging is ambiguous. Acknowledgements: This study was supported by a grant of the Korean Health Technology R&D Project, Ministry for Health, Welfare & Family Affairs, (A070001) Republic of Korea.

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What Is the Clinical Significance of FDG Unexpected Uptake in the Prostate in Patients Undergoing PET/CT for Other Malignancies?

International Journal of Molecular Imaging ◽

10.1155/2013/476786 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 8

Author(s):

Priya Bhosale ◽

Aparna Balachandran ◽

Raghu Vikram ◽

Chitra Viswanathan ◽

Homer Macapinlac ◽

...

Keyword(s):

Clinical Significance ◽

Prostate Carcinoma ◽

Fdg Pet ◽

Prostate Gland ◽

Elevated Serum ◽

Standardized Uptake Value ◽

Prior History ◽

Fdg Uptake ◽

Pet Ct ◽

Fdg Pet Ct

Purpose. To determine the clinical significance of unexpected, abnormal FDG uptake in the prostate in patients undergoing FDG-PET/CT for staging of other primary malignancies without a prior history of prostate carcinoma. Methods. Retrospective search of FDG-PET/CT studies to identify patients with unexpected, abnormal FDG uptake in the prostate gland, who underwent subsequent biopsy, was performed. 26 patients were identified. Images were reviewed to determine the pattern of uptake within the prostate (focal or diffuse) and maximum standardized uptake value (SUVmax). PSA and Gleason scores were recorded. Results. 15/26 (58%) patients were found to have prostate carcinoma. Gleason scores ranged from 6 to 9.9. There was no statistical difference in the pattern of uptake (focal versus diffuse) or the SUVmax. Serum PSA levels with cancer (range, 2–26.8 ng; mean, 10.2 ng) and those without cancer (range, 2–10.5 ng; mean, 2.2 ng) were statistically significant (P<0.007, Wilcoxon rank sum test). Conclusions. Patients with abnormal uptake in the prostate have a 58% likelihood of occult prostate cancer. In the setting of elevated serum PSA levels, abnormal prostate uptake should therefore be viewed with suspicion and a urology consult should be obtained; however, it is irrelevant in patients with underlying aggressive malignancies.

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Incidental colorectal focal 18F-FDG uptake: a novel indication for colonoscopy

Endoscopy International Open ◽

10.1055/s-0043-116384 ◽

2017 ◽

Vol 05 (09) ◽

pp. E924-E930 ◽

Cited By ~ 2

Author(s):

Eugénie Rigault ◽

Laurence Lenoir ◽

Guillaume Bouguen ◽

Mael Pagenault ◽

Astrid Lièvre ◽

...

Keyword(s):

False Positive ◽

Fdg Pet ◽

True Positive ◽

Fdg Uptake ◽

Endoscopic Findings ◽

Pet Ct ◽

Uptake Sites ◽

Malignant Lesions ◽

18F Fdg ◽

Fdg Pet Ct

Abstract Background and study aims The relevance of incidental colorectal focal 18F-FDG PET/CT uptake is debatable. All patients who were referred for colonoscopy because of incidental colonic focal FDG uptake were included in this retrospective study. Patients and methods PET/CT imaging characteristics were reviewed by a nuclear physician who was blinded to endoscopic and histopathological findings to determine the location of FDG uptake sites and to measure the maximum standardized uptake values (SUVmax) and metabolic volume (MV). Endoscopic findings were categorized as malignant lesions (ML), high-risk polyps (HRP), low-risk polyps (LRP) or other non-neoplastic lesions (NNL). Results Seventy patients with 84 foci of FDG uptake were included. The proportions of true-positive (lesions found at colonoscopy at the same location) and false-positive (no lesion at colonoscopy) PET/CT findings were 65.5 % (n = 55) and 34.5 % (n = 29). Median SUVmax values did not differ between true-positive and false-positive findings (P = 0.27). Median MV30 values differed significantly between true-positive (5.5 cm3, [3.3 – 10.9 cm3]) and false-positive (9.7 cm3, [5.2 – 40.8 cm3]) findings (P = 0.015). Among the 55 true-positive FDG uptake sites, there were 14 (25.5 %) malignant lesions, 30 (54.5 %) HRP, 4 (7.3 %) LRP, and 7 (12.7 %) NNL. Median MV30 values differed significantly between advanced neoplasia (5.0 cm3, [2.9 – 9.7 cm3]) and other endoscopic findings (9.4 cm3, [5.2 – 39.8 cm3]) (P = 0.001); the AUROC was 0.71. By per-colonic segment analysis, the distribution of true-positive, false-negative, false-positive, and true-negative FDG PET/CT findings was as follows: 21.5 %, 14.2 %, 11.5 %, and 52.8 %, respectively. Conclusion Our study demonstrates that follow-up complete colonoscopy is mandatory in all patients with incidental colorectal focal 18F-FDG PET/CT uptake.

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The role of FDG PET/CT or PET/MRI in assessing response to neoadjuvant therapy for patients with borderline or resectable pancreatic cancer: a systematic literature review

Annals of Nuclear Medicine ◽

10.1007/s12149-021-01629-0 ◽

2021 ◽

Author(s):

Laura Evangelista ◽

Pietro Zucchetta ◽

Lucia Moletta ◽

Simone Serafini ◽

Gianluca Cassarino ◽

...

Keyword(s):

Neoadjuvant Therapy ◽

Fdg Pet ◽

Standardized Uptake Value ◽

Response To Therapy ◽

Ductal Adenocarcinoma ◽

Resectable Pancreatic Cancer ◽

Number Of Patients ◽

Pet Ct ◽

Fdg Pet Ct

AbstractThe aim of the present systematic review is to examine the role of fluorodeoxyglucose (FDG) positron emission tomography (PET) associated with computed tomography (CT) or magnetic resonance imaging (MRI) in assessing response to preoperative chemotherapy or chemoradiotherapy (CRT) for patients with borderline and resectable pancreatic ductal adenocarcinoma (PDAC). Three researchers ran a database query in PubMed, Web of Science and EMBASE. The total number of patients considered was 488. The most often used parameters of response to therapy were the reductions in the maximum standardized uptake value (SUVmax) or the peak standardized uptake lean mass (SULpeak). Patients whose SUVs were higher at the baseline (before CRT) were associated with a better response to therapy and a better overall survival. SUVs remaining high after neoadjuvant therapy correlated with a poor prognosis. Available data indicate that FDG PET/CT or PET/MRI can be useful for predicting and assessing response to CRT in patients with resectable or borderline PDAC.

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