1
|
Califaretti E, Dall'armellina S, Rovera G, Finessi M, Deandreis D. The role of PET/CT in thyroid autoimmune diseases. THE QUARTERLY JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING : OFFICIAL PUBLICATION OF THE ITALIAN ASSOCIATION OF NUCLEAR MEDICINE (AIMN) [AND] THE INTERNATIONAL ASSOCIATION OF RADIOPHARMACOLOGY (IAR), [AND] SECTION OF THE SOCIETY OF... 2022; 66:218-228. [PMID: 35612371 DOI: 10.23736/s1824-4785.22.03464-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Autoimmune thyroid diseases (AITD) are a heterogeneous group of disorders. They include, in particular, Graves' disease and Hashimoto's thyroiditis with a wide range of different functional status ranging from subclinical biochemical abnormalities to severe hyperthyroidism or severe hypothyroidism respectively. Furthermore, other conditions more frequently infectious or drug related can cause an immune reaction in the thyroid tissue. In AITDs, positron emission tomography/computed tomography (PET/CT) does not play a primary role for disease diagnosis or management, but accidental findings can occur in both symptomatic and asymptomatic patients, and they should be recognized and well interpreted. A comprehensive literature search of the PubMed databases was conducted to identify papers (systematic review, prospective and retrospective study, case report) evaluating the role of PET/CT in thyroid autoimmune diseases. Thyroid diffuse uptake of 18F-fluoro-2-deoxy-2-d-glucose ([18F]FDG) has been shown to be frequently associated with AITDs, but also with immune-induced thyroid disorders related to SARS-CoV-2 or immunotherapy, while malignant lesions more often have a focal aspect. Other radiopharmaceuticals as [68Ga]-DOTA-peptides, [68Ga]-fibroblast activation protein inhibitors (FAPIs) and [68Ga]-prostate specific membrane antigen ([68Ga]-PSMA) showed similar findings. In conclusion, PET/CT scan in AITDs does not play a primary role in the diagnosis, but the occasional finding of a thyroid uptake must always be described in the report and possibly investigated for a better patient's management.
Collapse
Affiliation(s)
- Elena Califaretti
- Unit of Nuclear Medicine, Department of Medical Sciences, Città della Salute e della Scienza, University of Turin, Turin, Italy
| | - Sara Dall'armellina
- Unit of Nuclear Medicine, Department of Medical Sciences, Città della Salute e della Scienza, University of Turin, Turin, Italy
| | - Guido Rovera
- Unit of Nuclear Medicine, Department of Medical Sciences, Città della Salute e della Scienza, University of Turin, Turin, Italy
| | - Monica Finessi
- Unit of Nuclear Medicine, Department of Diagnostic Imaging and Interventional Radiology, Città della Salute e della Scienza, Turin, Italy -
| | - Désirée Deandreis
- Unit of Nuclear Medicine, Department of Medical Sciences, Città della Salute e della Scienza, University of Turin, Turin, Italy
- Unit of Nuclear Medicine, Department of Diagnostic Imaging and Interventional Radiology, Città della Salute e della Scienza, Turin, Italy
| |
Collapse
|
2
|
Characteristics of malignant thyroid lesions on [ 18F] fluorodeoxyglucose (FDG)-Positron emission tomography (PET)/Computed tomography (CT). Eur J Radiol Open 2021; 8:100373. [PMID: 34458507 PMCID: PMC8379667 DOI: 10.1016/j.ejro.2021.100373] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 08/07/2021] [Accepted: 08/12/2021] [Indexed: 11/22/2022] Open
Abstract
Objectives To determine the imaging variables that can best differentiate malignant from benign thyroid lesions incidentally found on F-18 FDG PET/CT scans. Methods All F-18 FDG PET/CT studies starting from 2011 to end of 2016 were reviewed for incidental thyroid lesions or metabolic abnormalities. Only patients who were found to have FNAB or histopathology were included. Patients with known thyroid malignancy were excluded. Patients were analyzed for age, sex, SUVmax, non-enhanced CT tissue density in mean Hounsfield units (HU), uptake pattern (focal or diffuse) and gland morphology (MNG or diffuse). A control group of 15 patients with normal thyroid glands were used to assess the tissue density in HU for normal thyroid tissue. Sensitivity, specificity, PPV, NPV and accuracy to detect malignancy were calculated. Pearson Chi-square test was used to compare categorical variables while unpaired T-test and one way ANOVA test were used to compare means of continuous variables. ROC analysis was used to assess the best cut off points for SUVmax and HU. Regression analysis was used to detect the independent predictors for malignant lesions. Results Biopsy was unsatisfactory or indeterminate in 4/48 patients (8%). Only 44 patients (mean age 55.2 ± 14.7; 30 females (68 %)) with unequivocal FNAB or histopathology were included for further analysis. MNG was noted in 17/44 patients (38.6 %). Thyroid malignancy was found in 16/44 (36.4 %), benign thyroid lesions in 28/44 (63.6 %). Thyroid malignancies were 12 papillary, 1 follicular, 1 Hurthle cell neoplasm and 2 lymphoma. Benign lesions were 23 benign follicular or colloid nodules and 5 autoimmune thyroiditis. Focal FDG uptake pattern was more frequently associated with malignant lesions compared to benign lesions (75 % vs. 43 %; p = 0.039). The mean SUVmax and tissue density (HU) were both higher in malignant than benign lesions (8.8 ± 8.3 vs. 3.6 ± 1.9, p = 0.024) and (48.9 ± 12.7 vs. 32.9 ± 17.5, p = 0.003) respectively. The mean HU in the control group with normal thyroid tissue was 90 ± 7.4 significantly higher than in both the benign and malignant lesions (p < 0.001). ROC analysis revealed SUVmax cutoff of >4.7 and HU cutoff of >42 to best differentiate malignant from benign lesions. The sensitivity, specificity, PPV, NPV and accuracy to detect malignancy for SUVmax>4.7 were 68.8 %, 78.6 %, 64.8 %, 81.5 & 75.0 % (p = 0.002), for HU > 42 were 81.3.0 %, 75.0 %, 65.0 %, 87.5 & 77.3 % (p = 0.0003) and for both parameters combined were 87.5 %, 60.7 %, 56.0 %, 89.5 % and accuracy of 70.5 % (p = 0.002) respectively. Only HU > 42 and SUVmax>4.7 were independent predictors for malignancy with odd ratios 8.98 and 4.93 respectively. Conclusion A higher tissue density (HU > 42) and SUVmax>4.7 as well as tendency for focal uptake pattern are the most significant characteristics associated with malignant thyroid lesions occasionally detected on PET/CT.
Collapse
|
3
|
Korsholm K, Reichkendler M, Alslev L, Rasmussen ÅK, Oturai P. Long-Term Follow-Up of Thyroid Incidentalomas Visualized with 18F-Fluorodeoxyglucose Positron Emission Tomography-Impact of Thyroid Scintigraphy in the Diagnostic Work-Up. Diagnostics (Basel) 2021; 11:diagnostics11030557. [PMID: 33808919 PMCID: PMC8003788 DOI: 10.3390/diagnostics11030557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 03/16/2021] [Accepted: 03/18/2021] [Indexed: 11/16/2022] Open
Abstract
Our objective was to evaluate the frequency of malignancy in incidental thyroidal uptake on 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in a cohort of Danish patients, and furthermore to evaluate the impact of thyroid scinti-graphy in the diagnostic work-up. All whole-body PET/CT reports from 1 January 2010 to 31 December 2013 were retrospectively reviewed and further analyzed if visually increased thyroidal FDG uptake was reported. Patient electronic files were searched for further thyroid evaluation. Of 13,195 18F-FDG-PET/CT scans in 9114 patients, 312 PET/CT reports mentioned incidental thyroid FDG-uptake, and 279 patients were included in the study (3.1%). The thyroid was further investigated in 137 patients (49%), and 75 patients underwent thyroid scintigraphy. A total of 57 patients had a thyroid biopsy and 21 proceeded to surgery. Surgical specimens displayed malignancy in 10 cases, and one thyroid malignancy was found by autopsy. Hence, 11 patients were diagnosed with thyroid malignancies among 279 patients with incidental thyroid 18F-FDG uptake (3.9%). In 34 patients, a biopsy was avoided due to the results of the thyroid scintigraphy. We conclude that patients with thyroid incidentalomas can benefit from further diagnostic work-up including a thyroid scintigraphy.
Collapse
Affiliation(s)
- Kirsten Korsholm
- Department of Clinical Physiology, Nuclear Medicine and PET, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark; (M.R.); (L.A.); (P.O.)
- Correspondence:
| | - Michala Reichkendler
- Department of Clinical Physiology, Nuclear Medicine and PET, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark; (M.R.); (L.A.); (P.O.)
| | - Louise Alslev
- Department of Clinical Physiology, Nuclear Medicine and PET, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark; (M.R.); (L.A.); (P.O.)
| | - Åse Krogh Rasmussen
- Department of Endocrinology, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark;
| | - Peter Oturai
- Department of Clinical Physiology, Nuclear Medicine and PET, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark; (M.R.); (L.A.); (P.O.)
| |
Collapse
|
4
|
Kim YH, Chang Y, Kim Y, Kim SJ, Rhee EJ, Kwon H, Ahn J, Ryu S. Diffusely Increased 18F-FDG Uptake in the Thyroid Gland and Risk of Thyroid Dysfunction: A Cohort Study. J Clin Med 2019; 8:jcm8040443. [PMID: 30987005 PMCID: PMC6517876 DOI: 10.3390/jcm8040443] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 03/28/2019] [Accepted: 03/28/2019] [Indexed: 01/21/2023] Open
Abstract
The impact of incidentally identified diffuse thyroid FDG uptake on 18F-FDG PET/CT scan on the incidence of thyroid dysfunction remains unclear. We examined the association of diffuse thyroid FDG uptake with the development of thyroid dysfunction. This cohort study involved 39,098 Korean adults who were free of malignancy and thyroid disease at baseline and underwent regular health checkup examinations including an 18F-FDG whole body PET/CT scan, thyroid-stimulating hormone and free thyroxine. The participants were annually or biennially followed for up to 5 years. A parametric proportional hazard model was used to estimate the adjusted hazard ratio (HR) and 95% confidence interval (CI). Diffuse thyroid uptake was positively associated with increased risk of thyroid dysfunction in both the cross-sectional and cohort studies. During 104,261.4 person-years of follow-up, 102 incident hypothyroidism cases and 172 hyperthyroidism cases were identified. Multivariable-adjusted HR (95% CI) for incident hypothyroidism or hyperthyroidism comparing diffuse thyroid uptake to no uptake were 15.72 (9.23–26.77) and 7.38 (4.23–12.87), respectively. In this large cohort, incidentally, identified diffuse thyroid uptake on 18F-FDG PET/CT was associated with increased risk of both prevalent and incident thyroid dysfunction. Therefore, baseline and follow-up evaluations in individuals with diffuse thyroid uptake may help identify individuals with thyroid dysfunction.
Collapse
Affiliation(s)
- Young Hwan Kim
- Department of Nuclear Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, 03181 Seoul, Korea.
| | - Yoosoo Chang
- Center for Cohort Studies, Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, 04514 Seoul, Korea.
- Department of Occupational and Environmental Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, 03181 Seoul, Korea.
- Department of Clinical Research Design & Evaluation, SAIHST, Sungkyunkwan University, 06351 Seoul, Korea.
| | - Yejin Kim
- Center for Cohort Studies, Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, 04514 Seoul, Korea.
- Department of Clinical Research Design & Evaluation, SAIHST, Sungkyunkwan University, 06351 Seoul, Korea.
| | - Soo Jeong Kim
- Department of Nuclear Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, 03181 Seoul, Korea.
| | - Eun-Jung Rhee
- Department of Endocrinology and Metabolism, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, 03181 Seoul, Korea.
| | - Hyemi Kwon
- Department of Endocrinology and Metabolism, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, 03181 Seoul, Korea.
| | - Jiin Ahn
- Center for Cohort Studies, Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, 04514 Seoul, Korea.
| | - Seungho Ryu
- Center for Cohort Studies, Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, 04514 Seoul, Korea.
- Department of Occupational and Environmental Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, 03181 Seoul, Korea.
- Department of Clinical Research Design & Evaluation, SAIHST, Sungkyunkwan University, 06351 Seoul, Korea.
| |
Collapse
|
5
|
Edo N, Morita K, Sakamoto M, Kaminaga T, Edo H, Okamura E, Ogawa M, Tsukamoto K, Okinaga H, Ishikawa T. Correlation between anti-thyroid peroxidase antibody levels and diffuse thyroid uptake of 18F-fluorodeoxyglucose in Hashimoto's thyroiditis: a retrospective study. Thyroid Res 2018; 11:14. [PMID: 30349584 PMCID: PMC6192302 DOI: 10.1186/s13044-018-0058-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 10/03/2018] [Indexed: 11/10/2022] Open
Abstract
Background On 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET), diffuse uptake in the thyroid gland is often observed in patients with Hashimoto’s thyroiditis. In this study, we evaluated the factors associated with diffuse uptake by comparing Hashimoto’s thyroiditis patients with or without diffuse uptake in the thyroid. Methods A retrospective study was conducted of 18 patients with Hashimoto’s thyroiditis who underwent blood tests, thyroid ultrasonography, and FDG-PET during the period from 2014 to 2015. The patients were divided into two groups: one with diffuse thyroid uptake (group 1, n = 13) and one without diffuse thyroid uptake (group 2, n = 5). Clinical and laboratory parameters, including maximum standardized uptake in the thyroid (SUVmax), which was defined as the higher value obtained in either the right or left thyroid lobe, were compared in the two groups. Results The frequency of abnormal findings, such as a rough or heterogeneous pattern, was significantly higher in group 1 (p < 0.01), as were anti-thyroid peroxidase (TPO) antibody titers, anti-thyroglobulin (Tg) antibody titers, and SUVmax (p < 0.01). The frequency of hypothyroidism did not differ significantly in the two groups. Anti-TPO and anti-Tg titers were positively correlated with SUVmax (r = 0.856, p < 0.01 and r = 0.821, p < 0.01, respectively); in univariate analysis, anti-TPO titer was predictive of SUVmax (p < 0.01). Conclusions The results of the current study suggest that Hashimoto’s thyroiditis patients with high titers of anti-thyroid antibodies are likely to exhibit intense diffuse FDG uptake in the thyroid, and that thyroid function may be clearly impaired, even in the presence of mild FDG uptake in the thyroid.
Collapse
Affiliation(s)
- Naoki Edo
- 1Department of Internal Medicine, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi, Tokyo, 173-0003 Japan
| | - Koji Morita
- 1Department of Internal Medicine, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi, Tokyo, 173-0003 Japan
| | - Miki Sakamoto
- 1Department of Internal Medicine, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi, Tokyo, 173-0003 Japan
| | - Tatsuro Kaminaga
- 2Department of Radiology, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi, Tokyo, 173-0003 Japan
| | - Hiromi Edo
- 3Department of Radiology, Toho University Ohashi Medical Center, 2-22-36, Ohashi, Meguro, Tokyo, Japan
| | - Erina Okamura
- 1Department of Internal Medicine, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi, Tokyo, 173-0003 Japan
| | - Masumi Ogawa
- 1Department of Internal Medicine, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi, Tokyo, 173-0003 Japan
| | - Kazuhisa Tsukamoto
- 1Department of Internal Medicine, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi, Tokyo, 173-0003 Japan
| | - Hiroko Okinaga
- 1Department of Internal Medicine, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi, Tokyo, 173-0003 Japan
| | - Toshio Ishikawa
- 1Department of Internal Medicine, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi, Tokyo, 173-0003 Japan
| |
Collapse
|
6
|
PET/CT and prediction of thyroid cancer in patients with follicular neoplasm or atypia. Eur Arch Otorhinolaryngol 2018; 275:2109-2117. [PMID: 29909471 DOI: 10.1007/s00405-018-5030-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 06/05/2018] [Indexed: 12/20/2022]
Abstract
PURPOSE To examine whether addition of 18F-fluoro-deoxy-glucose positron emission tomography/computed tomography (FDG-PET/CT) to fine needle aspiration biopsy (FNAB) would improve prediction of thyroid cancer in patients with FNAB-derived follicular neoplasm or atypia, classified according to focal, multifocal, diffuse, or no FDG uptake. MATERIALS AND METHODS Consecutive patients with FNAB-derived follicular neoplasm or atypia planned for surgery from September 2013 to March 2016 were prospectively included and considered for analysis. All patients underwent preoperative PET/CT and a clinical head and neck examination, including ultrasound of the neck and the thyroid gland. Patients with obvious signs of thyroid malignancy were excluded from the study. Histology of the surgical specimen was used as reference standard for statistical analysis. RESULTS Of the 108 patients included (85 women, median age 53.4 years), 31 (29%) had a thyroid nodule that was histologically verified as malignant. Sensitivity and specificity for PET/CT in detection of thyroid cancer was 79 and 32%, respectively, including a derived positive predictive value (PPV) of 31%, and a negative predictive value (NPV) of 79%. Univariate and multivariate analyses showed no significant increase in the risk of thyroid cancer among patients with focal or multifocal FDG uptake compared to patients with no FDG uptake. CONCLUSION Addition of PET/CT to FNAB did not improve prediction of thyroid cancer in patients with FNAB-derived follicular neoplasm or atypia.
Collapse
|
7
|
Tamburello A, Treglia G, Albano D, Bertagna F, Giovanella L. Prevalence and clinical significance of focal incidental 18F-FDG uptake in different organs: an evidence-based summary. Clin Transl Imaging 2017. [DOI: 10.1007/s40336-017-0253-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
8
|
Algin E, Uner A, Akdemir UO, Gumusay O, Kapucu O, Ozet A. The assessment of incidental thyroid lesions on 18F-fluorodeoxyglucose positron emission tomography/computed tomogrophy: A single centre experience. JOURNAL OF ONCOLOGICAL SCIENCES 2017. [DOI: 10.1016/j.jons.2017.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
|
9
|
Martinez B, Soñanez-Organis JG, Godoy-Lugo JA, Horin LJ, Crocker DE, Ortiz RM. Thyroid hormone-stimulated increases in PGC-1α and UCP2 promote life history-specific endocrine changes and maintain a lipid-based metabolism. Am J Physiol Regul Integr Comp Physiol 2016; 312:R189-R196. [PMID: 27903512 DOI: 10.1152/ajpregu.00395.2016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 10/31/2016] [Accepted: 11/18/2016] [Indexed: 12/12/2022]
Abstract
Thyroid hormones (THs) regulate metabolism, but are typically suppressed during times of stressful physiological conditions, including fasting. Interestingly, prolonged fasting in northern elephant seal pups is associated with reliance on a lipid-based metabolism and increased levels of circulating THs that are partially attributed to active secretion as opposed to reduced clearance. This apparent paradox is coupled with complementary increases in cellular TH-mediated activity, suggesting that in mammals naturally adapted to prolonged fasting, THs are necessary to support metabolism. However, the functional relevance of this physiological paradox has remained largely unexplored, especially as it relates to the regulation of lipids. To address the hypothesis that TSH-mediated increase in THs contributes to lipid metabolism, we infused early and late-fasted pups with TSH and measured several key genes in adipose and muscle, and plasma hormones associated with regulation of lipid metabolism. TSH infusion increased the mRNA expressions of peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) more than 6.5-fold at 60 min in muscle, and expression of uncoupling protein 2 (UCP2) more than 27-fold during the early fast at 60 min, in adipose. Additionally, during the late fast period, the protein content of adipose CD36 increased 1.1-fold, and plasma nonesterified fatty acid (NEFA) concentrations increased 25% at 120 min, with NEFA levels returning to baseline after 24 h. We show that the TSH-induced increases in THs in fasting pups are functional and likely contribute to the maintenance of a lipid-based metabolism.
Collapse
Affiliation(s)
- Bridget Martinez
- Molecular and Cellular Biology, University of California Merced, Merced, California;
| | - José G Soñanez-Organis
- Departamento de Ciencias Químico Biológicas y Agropecuarias, Universidad de Sonora, Francisco Villa, Navojoa Sonora, México
| | - José Arquimides Godoy-Lugo
- Departamento de Ciencias Químico Biológicas y Agropecuarias, Universidad de Sonora, Francisco Villa, Navojoa Sonora, México
| | - Lillian J Horin
- W. M. Keck Science Department, Pitzer College, Claremont, California; and
| | - Daniel E Crocker
- Department of Biology, Sonoma State University, Rohnert Park, California
| | - Rudy M Ortiz
- Molecular and Cellular Biology, University of California Merced, Merced, California
| |
Collapse
|
10
|
Martinez B, Soñanez-Organis JG, Viscarra JA, Jaques JT, MacKenzie DS, Crocker DE, Ortiz RM. Glucose delays the insulin-induced increase in thyroid hormone-mediated signaling in adipose of prolong-fasted elephant seal pups. Am J Physiol Regul Integr Comp Physiol 2016; 310:R502-12. [PMID: 26739649 DOI: 10.1152/ajpregu.00054.2015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Accepted: 01/04/2016] [Indexed: 12/14/2022]
Abstract
Prolonged food deprivation in mammals typically reduces glucose, insulin, and thyroid hormone (TH) concentrations, as well as tissue deiodinase (DI) content and activity, which, collectively, suppress metabolism. However, in elephant seal pups, prolonged fasting does not suppress TH levels; it is associated with upregulation of adipose TH-mediated cellular mechanisms and adipose-specific insulin resistance. The functional relevance of this apparent paradox and the effects of glucose and insulin on TH-mediated signaling in an insulin-resistant tissue are not well defined. To address our hypothesis that insulin increases adipose TH signaling in pups during extended fasting, we assessed the changes in TH-associated genes in response to an insulin infusion in early- and late-fasted pups. In late fasting, insulin increased DI1, DI2, and THrβ-1 mRNA expression by 566%, 44%, and 267% at 60 min postinfusion, respectively, with levels decreasing by 120 min. Additionally, we performed a glucose challenge in late-fasted pups to differentiate between insulin- and glucose-mediated effects on TH signaling. In contrast to the insulin-induced effects, glucose infusion did not increase the expressions of DI1, DI2, and THrβ-1 until 120 min, suggesting that glucose delays the onset of the insulin-induced effects. The data also suggest that fasting duration increases the sensitivity of adipose TH-mediated mechanisms to insulin, some of which may be mediated by increased glucose. These responses appear to be unique among mammals and to have evolved in elephant seals to facilitate their adaptation to tolerate an extreme physiological condition.
Collapse
Affiliation(s)
- Bridget Martinez
- Department of Molecular & Cellular Biology, University of California, Merced, California;
| | - José G Soñanez-Organis
- Departamento de Ciencias Químico Biológicas y Agropecuarias, Universidad de Sonora, Navojoa, Sonora, México
| | - Jose A Viscarra
- Department of Molecular & Cellular Biology, University of California, Merced, California
| | - John T Jaques
- Veterinary Medical Diagnostic Laboratory, Texas A&M University, College Station, Texas
| | - Duncan S MacKenzie
- Department of Biology, Texas A&M University, College Station, Texas; and
| | - Daniel E Crocker
- Department of Biology, Sonoma State University, Rohnert Park, California
| | - Rudy M Ortiz
- Department of Molecular & Cellular Biology, University of California, Merced, California
| |
Collapse
|
11
|
Thyroid lesions incidentally detected by (18)F-FDG PET-CT - a two centre retrospective study. Radiol Oncol 2015; 49:121-7. [PMID: 26029022 PMCID: PMC4387987 DOI: 10.2478/raon-2014-0039] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Accepted: 09/22/2014] [Indexed: 11/20/2022] Open
Abstract
Background. Incidental 18F-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 evaluated 18F-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 SUVmax of the thyroid lesion was calculated. Patients with incidental 18F-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. Incidental 18F-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 SUVmax of 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 SUVmax of 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. Incidental 18F-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. SUVmax should only serve as one of several parameters that alert the clinician on the possibility of thyroid malignancy.
Collapse
|
12
|
Agrawal K, Weaver J, Ngu R, Krishnamurthy Mohan H. Clinical significance of patterns of incidental thyroid uptake at (18)F-FDG PET/CT. Clin Radiol 2015; 70:536-43. [PMID: 25687827 DOI: 10.1016/j.crad.2014.12.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 12/22/2014] [Accepted: 12/29/2014] [Indexed: 10/24/2022]
Abstract
Incidental uptake of 2-[(18)F]-fluoro-2-deoxy-d-glucose ((18)F-FDG) in the thyroid gland is not uncommonly encountered in day-to-day practice of oncological (18)F-FDG positron-emission tomography/computed tomography (PET/CT). These are often felt to be "nuisance lesions" by referring clinicians and radiologists alike. However, recognition of the importance of different patterns of FDG uptake in the thyroid gland and knowledge of the possible underlying aetiologies are crucial in ensuring that patients are managed appropriately in the clinical context of their primary diagnosis, as the underlying pathological condition may be clinically important in a significant minority of such cases. This review describes the various patterns of (18)F-FDG uptake within the thyroid and discusses the clinical significance and possible impact on patient management. Incidental low-grade homogeneous diffuse increased thyroid (18)F-FDG uptake is usually seen in the patients with chronic thyroiditis, Grave's disease, and hypothyroidism. Thyroid function tests and antibody profiling are advised in these patients. Incidental focal (18)F-FDG thyroid uptake should raise the possibility of underlying malignancy. Ultrasound with or without fine-needle aspiration cytology is usually recommended for the evaluation of these lesions. Heterogeneous uptake with prominent focal uptake in the thyroid should be further evaluated to exclude malignancy.
Collapse
Affiliation(s)
- K Agrawal
- Dept of Nuclear Medicine, Guy's and St Thomas' NHS Foundation Trust, London, UK.
| | - J Weaver
- School of medicine, King's College London, London, UK
| | - R Ngu
- Department of Dental Maxillofacial Radiology, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - H Krishnamurthy Mohan
- Dept of Nuclear Medicine, Guy's and St Thomas' NHS Foundation Trust, London, UK; Clinical PET Centre, St Thomas' Hospital, London, UK
| |
Collapse
|
13
|
The usefulness of standardized uptake value in differentiation between benign and malignant thyroid lesions detected incidentally in 18F-FDG PET/CT examination. PLoS One 2014; 9:e109612. [PMID: 25296297 PMCID: PMC4190406 DOI: 10.1371/journal.pone.0109612] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2014] [Accepted: 09/01/2014] [Indexed: 11/19/2022] Open
Abstract
Introduction In the last decade, (18)F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET and PET/CT) has become one of the major diagnostic tools used in oncology. A significant number of patients who undergo this procedure, due to non-thyroidal reasons, present incidental uptake of (18F-FDG) in the thyroid. The aim of the study was to compare the SUVmax (standardized uptake value) of thyroid focal lesions, which were incidentally found on PET/CT, in relation to the results of thyroid fine-needle aspiration biopsy (FNAB) and/or histopathological evaluation. Materials and Methods Patients referred for PET/CT examination, due to non-thyroidal illness, presented focal 18F-FDG uptake in the thyroid and were advised to undergo ultrasonography (US), hormonal evaluation, FNAB and/or total thyroidectomy at our institution. Results 6614 PET/CT examinations performed in 5520 patients were analyzed. Of the 122 patients with focal thyroid 18F-FDG activity, 82 patients (67.2%) underwent further thyroid evaluation using FNAB. Benign lesions were diagnosed in 46 patients, malignant - in 19 patients (confirmed by post-surgical histopathology), while 17 patients had inconclusive results of cytological assessment. Mean SUVmax of benign lesions was 3.2±2.8 (median = 2.4), while the mean SUVmax value for malignant lesions was 7.1±8.2 (median = 3.5). The risk of malignancy was 16.7% for lesions with a SUVmax under 3, 43.8% for lesions with a SUVmax between 3 and 6, and 54.6% for lesions with a SUVmax over 6. In the group of malignant lesions, a positive correlation between the lesion’s diameter and SUVmax was observed (p = 0.03, r = 0.57). Conclusions Subjects with incidental focal uptake of 18F-FDG in thyroid are at a high risk of thyroid malignancy. A high value of SUVmax further increases the risk of malignancy, indicating the necessity for further cytological or histological evaluation. However, as SUVmax correlated with the diameter of malignant lesions, small lesions with focal uptake of 18F-FDG should be interpreted cautiously.
Collapse
|
14
|
Qu N, Zhang L, Lu ZW, Wei WJ, Zhang Y, Ji QH. Risk of malignancy in focal thyroid lesions identified by (18)F-fluorodeoxyglucose positron emission tomography or positron emission tomography/computed tomography: evidence from a large series of studies. Tumour Biol 2014; 35:6139-47. [PMID: 24622887 DOI: 10.1007/s13277-014-1813-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Accepted: 02/28/2014] [Indexed: 11/24/2022] Open
Abstract
Focal thyroid incidentaloma identified on (18)F-fluorodeoxyglucose positron emission tomography or positron emission tomography/computed tomography ((18)F-FDG PET or PET/CT) indicates a high risk of thyroid malignancy. A meta-analysis was performed to investigate whether the maximum standardized uptake value (SUVmax) could discriminate between benign and malignant tissues in focal lesions and to explore the cutoff value of SUVmax for the diagnosis of malignancy. A total of 29 studies were involved in this meta-analysis. The results indicated that there was no statistically significant difference in the size of the two benign and malignant groups when measured by ultrasonography (95 % confidence interval (CI), -0.79 to 0.03 min; p=0.07), while a significantly higher focal SUVmax was observed in the malignant group (95 % CI, 0.34 to 1.05; p=0.0001). In conclusion, the findings of this meta-analysis suggest that a higher focal (18)F-FDG SUVmax was associated with a higher risk of thyroid malignancy, especially at a threshold of 3.3 or more.
Collapse
Affiliation(s)
- Ning Qu
- Department of Head and Neck Surgery, Fudan University Shanghai Cancer Center and Department of Oncology, Shanghai Medical College, Fudan University, 200032, Shanghai, China
| | | | | | | | | | | |
Collapse
|
15
|
Lee JY, Choi JY, Choi YH, Hyun SH, Moon SH, Jang SJ, Choe YS, Lee KH, Kim BT. Diffuse thyroid uptake incidentally found on 18F-fluorodeoxyglucose positron emission tomography in subjects without cancer history. Korean J Radiol 2013; 14:501-9. [PMID: 23690721 PMCID: PMC3655308 DOI: 10.3348/kjr.2013.14.3.501] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Accepted: 12/26/2012] [Indexed: 11/16/2022] Open
Abstract
Objective We investigated the clinical significance of incidental diffuse thyroid uptake (DTU) on 18F-FDG PET in subjects without a history of cancer. Materials and Methods This study included 2062 studies from adults who underwent 18F-FDG PET as a cancer screening program. Subjects were divided into the following two groups: with (group I) or without (group II) DTU. The presence of DTU and the thyroid visual grading score were compared with thyroid function tests, serum anti-microsomal antibody (AMA) levels, and the presence of diffuse parenchymal change (DPC) on ultrasonography (USG). Results DTU was found in 6.6% of the scans (137/2062). Serum thyroid stimulating hormone (TSH) and AMA levels were significantly higher in group I than in group II. Increased AMA level (55.1%) and DPC (48.7%) were more frequently found in group I (p < 0.001). The proportion of subjects with any abnormal results in serum free thyroxine, triiodothyronine, TSH, or AMA levels or DPC on USG was significantly higher in group I than in group II (71.5% vs. 10.6%, p < 0.001), and was significantly and gradually increased according to the visual grading score group (0 vs. 1-2 vs. 3-4 = 10.6% vs. 58.5% vs. 90.9%, p < 0.001). TSH and is AMA levels were significantly increased according to the visual grading score. Conclusion The presence or degree of incidental DTU on 18F-FDG PET is closely correlated with increased serum AMA and TSH levels, and the presence of DPC on USG. Therefore, the most plausible pathological cause of DTU may be cell damage by an autoimmune mechanism.
Collapse
Affiliation(s)
- Ji Young Lee
- Department of Nuclear Medicine, CHA Bundang Medical Center, CHA University, Seongnam 463-712, Korea
| | | | | | | | | | | | | | | | | |
Collapse
|
16
|
|
17
|
Boeckmann J, Bartel T, Siegel E, Bodenner D, Stack BC. Can the pathology of a thyroid nodule be determined by positron emission tomography uptake? Otolaryngol Head Neck Surg 2012; 146:906-12. [PMID: 22307576 DOI: 10.1177/0194599811435770] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVES To determine if standardized uptake values (SUV) on positron emission tomography (PET) are predictive of thyroid pathology and the significance of serial SUV measurements of thyroid nodules over time. STUDY DESIGN Case series with chart review. SETTING Academic health center. SUBJECTS In total, 23,384 PET and PET/computed tomography (CT) scans were performed between December 2001 and April 2011. METHODS Patients with incidental thyroid uptake were identified. SUV(max), age, sex, size of thyroid lesion, indication for PET scan, and cytology/pathology were collected. RESULTS Incidental thyroid uptake was noted in 1309 PET scans (5.60%), focal uptake in 690 (2.95%), and diffuse uptake in 619 (2.65%). Complete data were available for 359 PET scans from 103 patients. Malignancy was identified in 28 patients (27%). Twenty-five of the 28 lesions (89%) were primary thyroid malignancies. A significant difference between malignant SUV(max) and benign SUV(max) was found (mean ± SD, 7.04 ± 7.88 for malignancies vs 3.85 ± 3.06 for benign tumors, P = .0292). Receiver operating characteristics curves were constructed on patients with PET data within 3 months of diagnosis and indicated that a SUV(max) of 4.2 differentiated maximally between benign and malignant lesions. Serial SUV uptake had no significant change over time. CONCLUSION All thyroid nodules with focal uptake on (18)F-fluorodeoxyglucose-PET/CT should be considered at higher risk of malignancy than those discovered incidentally by other imaging modalities. Higher SUV(max) values are more indicative of malignant lesions. All lesions should be evaluated with ultrasonography ± fine-needle aspiration if no clinical contraindications exist. Size of the primary nodule does not influence SUV(max) uptake.
Collapse
Affiliation(s)
- Jacob Boeckmann
- Department of Otolaryngology-Head and Neck Surgery, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA
| | | | | | | | | |
Collapse
|
18
|
Wong C, Lin M, Chicco A, Benson R. The clinical significance and management of incidental focal FDG uptake in the thyroid gland on positron emission tomography/computed tomography (PET/CT) in patients with non-thyroidal malignancy. Acta Radiol 2011; 52:899-904. [PMID: 21873505 DOI: 10.1258/ar.2011.110078] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND Incidental focal fluorine-18-2-fluoro-2-deoxy-D-glucose (FDG) uptake in the thyroid is not uncommon. A significant proportion is due to intercurrent thyroid cancer on further evaluation. PURPOSE To investigate and discuss the clinical significance and management of incidental focal FDG uptake in the thyroid gland on positron emission tomography/computed tomography (PET/CT) in patients with non-thyroidal malignancy. MATERIAL AND METHODS We investigated 188/7896 (2.4%) patients who had incidental focal thyroid uptake on FDG PET/CT in an oncology population over a 45-month period. Diagnosis was confirmed in 63 patients of whom 59 patients had histopathological verification. RESULTS Thirty-two percent of confirmed cases were malignant comprising intercurrent thyroid cancer in three-quarters of these patients. Maximum standardized uptake values of the thyroid lesions and SUV ratios compared with background thyroid and mediastinal uptake were not predictive of a benign or malignant etiology. In patients with incidental thyroid cancers, more than half had non-papillary and intermediate to high-risk pathology. CONCLUSION Focal FDG uptake in the thyroid gland on PET/CT showed a malignancy risk of 32%. The intensity of uptake does not predict histology and underpins the importance of further investigations to exclude intercurrent thyroid cancer in suitable patients.
Collapse
Affiliation(s)
| | - Michael Lin
- University of New South Wales, Australia
- Department of Nuclear Medicine and PET, Liverpool Hospital, Liverpool, New South Wales, Australia
| | - Andrew Chicco
- Department of Nuclear Medicine and PET, Liverpool Hospital, Liverpool, New South Wales, Australia
| | - Rhonda Benson
- Department of Nuclear Medicine and PET, Liverpool Hospital, Liverpool, New South Wales, Australia
| |
Collapse
|
19
|
Chen YK, Yeh CL, Chen YL, Wang SC, Cheng RH, Kao PF. The frequency and spectrum of thymus 2-[fluorine-18] fluoro-2-deoxy-D-glucose uptake patterns in hyperthyroidism patients. Acad Radiol 2011; 18:1292-7. [PMID: 21893295 DOI: 10.1016/j.acra.2011.05.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Revised: 04/27/2011] [Accepted: 05/02/2011] [Indexed: 01/15/2023]
Abstract
RATIONALE AND OBJECTIVES Thymic hyperplasia is associated with hyperthyroidism. Increased thymus 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG) uptake in hyperthyroidism patients has been reported. The aim of this study was to analyze the FDG positron emission tomography (PET) thymus uptake spectrum in patients with active hyperthyroidism with correlation with serum hormones. MATERIALS AND METHODS The prospective study included FDG PET scans from 65 hyperthyroidism patients and 30 subjects with euthyroid status as control group. The intensity of FDG uptake in thyroid and thymus regions was graded subjectively on a five-point scale and semi-quantitatively by measuring standard uptake value (SUV). Correlation coefficient between thymus SUV and serum thyroxine, triiodothyronine, thyrotropin, thyroid peroxidase antibodies (TPO Ab), thyrotropin receptor autoantibody (TR Ab), and thymulin were analyzed. RESULTS Among 65 hyperthyroidism patients, 30 (46.2%) and 39 (60%) patients showed thyroid and thymus FDG uptake, respectively. The frequency of thymus uptake FDG was high in patients younger than age 40 (28/31, 90.3%). The patterns of the thymic FDG uptake include inverted V or triangular, separated triangular, united nontriangular, unilateral right or left extension, and focal midline. Focal midline FDG uptake was the most common pattern (15/39, 38.5%). None of the control group showed thymus FDG uptake. The correlation coefficient between the FDG uptake SUV levels in thymus and serum hormones, thyrotropin, TPO Ab, TR Ab, and thymulin levels were all low (P > .05). CONCLUSIONS In FDG PET scan, thymus activity was common in hyperthyroidism patients; this should not be misdiagnosed as a malignancy in patients exhibiting weight loss.
Collapse
|
20
|
Clinical Significance of Diffuse (18)F-FDG Uptake in Residual Thyroid Gland after Unilateral Thyroid Lobectomy. Nucl Med Mol Imaging 2011; 45:197-202. [PMID: 24900004 DOI: 10.1007/s13139-011-0097-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Accepted: 06/30/2011] [Indexed: 10/18/2022] Open
Abstract
PURPOSE We investigated the clinical significance of diffuse uptake in remaining thyroid after unilateral lobectomy for thyroid cancer. METHODS A total of 144 thyroid cancer patients who underwent (18)F-FDG PET/CT after lobectomy were enrolled in the present study. The PET/CT images were evaluated for the presence of diffuse (18)F-FDG uptake with maximum SUV (SUVmax) >2.0 in the residual thyroid and placed into one of two groups: with diffuse uptake and without diffuse uptake group. Clinical, laboratory, and PET/CT parameters in both groups were compared. Correlations between SUVmax of thyroid and available parameters were analyzed. RESULTS Forty-two of 144 patients (29.2%) had diffuse thyroid uptake (mean SUVmax: 3.2 ± 1.1). All patients with diffuse uptake and 96 (94.1%) without diffuse uptake were receiving thyroxine therapy (P = 0.09). Thyroid function tests showed that most patients were euthyroid status (78.6 vs. 85.3%, P = 0.36). TgAb levels were significantly higher in patients with diffuse uptake (338.0 ± 664.6 vs. 57.3 ± 46.4, P < 0.0001). Mean attenuation values in the diffuse uptake group were significantly lower (72.2 ± 15. vs. 97.0 ± 16.0, P < 0.0001). An inverse correlation was found between SUVmax and mean attenuation values of residual thyroid in all patients (r = -0.57, P < 0.0001) and subgroup with diffuse uptake (r = -0.31, P < 0.05). CONCLUSION In this study, diffuse (18)F-FDG uptake in the residual thyroid after unilateral lobectomy was a relatively frequent finding and may be associated with chronic thyroiditis. This uptake is not influenced by thyroid status or thyroxine therapy. The (18)F-FDG uptake is inversely correlated with mean attenuation value of thyroid.
Collapse
|
21
|
Abstract
The introduction of PET(-CT) has brought about a major paradigm shift in the management of thyroid carcinoma, especially from the diagnostic standpoint. From the viewpoint of patient management, the areas where it has made significant impact include the following: (1) the detection of disease focus in patients with differentiated thyroid carcinoma with elevated Tg levels and negative radioiodine scan. When localized disease is identified with F-18 FDG-PET-CT, surgery or focused radiotherapy could be utilized to eradicate the tumor; (2) the localization of disease in patients of MTC with elevated serum calcitonin levels; (3) the detection of unsuspected focal F-18 FDG uptake in the thyroid in patients undergoing whole body F-18 FDG PET for a different indication. This would prompt a workup to rule out thyroid carcinoma. The use of I-124 is evolving at this time and has been of great promise with regard to (a) its better efficacy of lesion detection and (b) the ability to provide lesion-specific dosimetry. In addition, F-18 FDG PET appears to be of potential value in patients with thyroid lymphoma in making the initial diagnosis, monitoring therapeutic response, and assessing for residual disease and/or recurrence.
Collapse
Affiliation(s)
- Sandip Basu
- Division of Nuclear Medicine, Hospital of the University of Pennsylvania, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | | | | | | |
Collapse
|
22
|
Diagnostic Value of CT Density in Patients With Diffusely Increased FDG Uptake in the Thyroid Gland on PET/CT Images. AJR Am J Roentgenol 2010; 195:223-8. [DOI: 10.2214/ajr.09.3319] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
23
|
Abstract
OBJECTIVE Adrenal nodules are frequently encountered on current high-resolution imaging, and accurate characterization of such lesions is critical for appropriate patient care. Our article highlights how imaging techniques such as CT densitometry, CT washout characteristics, chemical shift MRI, PET, and PET/CT help characterize most adrenal lesions. We focus on these techniques as well as specifically, because of space constraints, the varied imaging appearances of adrenocortical carcinoma, pheochromocytoma, and lymphoma on these techniques. CONCLUSION The imaging characterization of adrenal lesions has continued to advance over the past decade as new technologies have evolved. CT, MRI, PET, and PET/CT are now established clinical techniques capable of differentiating benign from malignant adrenal lesions.
Collapse
|
24
|
Shie P, Cardarelli R, Sprawls K, Fulda KG, Taur A. Systematic review: prevalence of malignant incidental thyroid nodules identified on fluorine-18 fluorodeoxyglucose positron emission tomography. Nucl Med Commun 2009; 30:742-8. [PMID: 19561553 DOI: 10.1097/mnm.0b013e32832ee09d] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE To review current literature and determine the prevalence of malignant incidental focal hypermetabolic thyroid lesions detected by fluorine-18 fluorodeoxyglucose positron emission tomography (F-FDG-PET). MATERIALS AND METHODS Studies evaluating thyroid carcinomas discovered incidentally on F-FDG-PET were systematically searched in the MEDLINE, CINAHL, and Evidence-Based Medicine (EBM) Reviews from 1998 to 2007. Studies were eligible for inclusion with the following criteria: F-FDG-PET studies carried out on humans, long-term clinical follow-up or presence of histological confirmation of thyroid disease, and if studies reported the prevalence of abnormal F-FDG-PET scans with thyroid lesions and confirmed pathological thyroid disease. Studies were excluded if (1) there was no confirmed diagnosis, (2) there was a history of thyroid cancer, (3) they were carried out for diagnoses of thyroid abnormalities, or (4) they were case series. Two reviewers independently reviewed each study's eligibility and abstracted the data. RESULTS Eighteen articles met criteria resulting in a total of 55 160 patients with 571 patients (1%) having an unexpected focal abnormality in the thyroid gland. Diagnostic confirmations were obtained in 322 patients. Among the confirmed diagnoses, 200 (62.1%) were benign, 107 (33.2%) were malignant, and 15 (4.7%) were indeterminate or a patient without a clear diagnosis. Papillary thyroid carcinoma was the most prevalent thyroid malignancy (82.2%). Eight studies reporting individual maximum standard uptake values were included in a subanalysis. The mean maximum standard uptake value for 73 benign lesions was 4.6+/-2.1, and for the 52 malignant lesions was 6.8+/-4.6 (P<0.001). CONCLUSION The high prevalence of malignancy associated with focal hypermetabolic thyroid nodules found on F-FDG-PET warrants further evaluation when detected.
Collapse
Affiliation(s)
- Philip Shie
- Diagnostic Imaging Services, Kaiser Permanente Fontana Medical Center, Fontana, California, USA.
| | | | | | | | | |
Collapse
|
25
|
Bae JS, Chae BJ, Park WC, Kim JS, Kim SH, Jung SS, Song BJ. Incidental thyroid lesions detected by FDG-PET/CT: prevalence and risk of thyroid cancer. World J Surg Oncol 2009; 7:63. [PMID: 19664272 PMCID: PMC2732624 DOI: 10.1186/1477-7819-7-63] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Accepted: 08/10/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Incidentally found thyroid lesions are frequently detected in patients undergoing FDG-PET/CT. The aim of this study was to investigate the prevalence of incidentally found thyroid lesions in patients undergoing FDG-PET/CT and determine the risk for thyroid cancer. METHODS FDG-PET/CT was performed on 3,379 patients for evaluation of suspected or known cancer or cancer screening without any history of thyroid cancer between November 2003 and December 2005. Medical records related to the FDG-PET/CT findings including maximum SUV(SUVmax) and pattern of FDG uptake, US findings, FNA, histopathology received by operation were reviewed retrospectively. RESULTS Two hundred eighty five patients (8.4%) were identified to have FDG uptake on FDG-PET/CT. 99 patients with focal or diffuse FDG uptake underwent further evaluation. The cancer risk of incidentally found thyroid lesions on FDG-PET/CT was 23.2% (22/99) and the cancer risks associated with focal and diffuse FDG uptake were 30.9% and 6.4%. There was a significant difference in the SUVmax between the benign and malignant nodules (3.35 +/- 1.69 vs. 6.64 +/- 4.12; P < 0.001). There was a significant correlation between the SUVmax and the size of the cancer. CONCLUSION The results of this study suggest that incidentally found thyroid lesions by FDG-PET/CT, especially a focal FDG uptake and a high SUV, have a high risk of thyroid malignancy. Further diagnostic work-up is needed in these cases.
Collapse
Affiliation(s)
- Ja Seong Bae
- Department of Surgery, The Catholic University of Korea, Seoul, Korea.
| | | | | | | | | | | | | |
Collapse
|
26
|
Wang X, Koch S. Positron emission tomography/computed tomography potential pitfalls and artifacts. Curr Probl Diagn Radiol 2009; 38:156-69. [PMID: 19464586 DOI: 10.1067/j.cpradiol.2008.01.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
With the recent use of 18-fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) for tumor staging and treatment response, it is important to recognize many pitfalls, artifacts, and benign uptakes that are commonly encountered. Normal physiology can explain many regions of increased FDG activity, as well as incidental benign tumors and benign metabolic conditions. Recognition of characterization of benign causes and physiologic variants for FDG uptake are discussed to avoid improper characterization as a malignancy. A basic understanding of PET/computed tomographic physics is also discussed, in relation to attenuation correction artifacts caused by metallic implants and contrast agents in the gastrointestinal tract, as well as artifacts caused in fused images due to patient motion. Also presented is the rationale for expected, benign uptake in various metabolic diseases, as well as pharmacologic methods for decreasing the artifacts caused by metabolic diseases. PET/computed tomographic evaluation of the thyroid, thymus, adrenal adenomas, uterus and ovaries, infection/inflammatory changes, and postradiation/chemotherapy changes are also discussed, with expected normal changes, as well as pitfalls and artifacts.
Collapse
Affiliation(s)
- Xia Wang
- Department of Radiology, Henry Ford Health System, Detroit, MI 48202-2689, USA
| | | |
Collapse
|
27
|
|
28
|
Clinical significance of thyroid uptake on F18-fluorodeoxyglucose positron emission tomography. Ann Nucl Med 2009; 23:17-23. [DOI: 10.1007/s12149-008-0198-0] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2008] [Accepted: 08/07/2008] [Indexed: 12/26/2022]
|
29
|
Tateishi U, Gamez C, Dawood S, Yeung HWD, Cristofanilli M, Inoue T, Macapinlac HA. Chronic thyroiditis in patients with advanced breast carcinoma: metabolic and morphologic changes on PET-CT. Eur J Nucl Med Mol Imaging 2009; 36:894-902. [PMID: 19156410 DOI: 10.1007/s00259-008-1048-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2008] [Accepted: 12/05/2008] [Indexed: 11/28/2022]
Affiliation(s)
- Ukihide Tateishi
- Department of Nuclear Medicine, University of Texas, MD Anderson Cancer Center, Houston, TX, USA.
| | | | | | | | | | | | | |
Collapse
|
30
|
Mirzaei S, Prosch H, Knoll P, Mostbeck G. Non-small Cell Lung Cancer. Cancer Imaging 2008. [DOI: 10.1016/b978-012374212-4.50030-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
31
|
Salvatori M, Melis L, Castaldi P, Maussier ML, Rufini V, Perotti G, Rubello D. Clinical significance of focal and diffuse thyroid diseases identified by 18F-fluorodeoxyglucose positron emission tomography. Biomed Pharmacother 2007; 61:488-93. [PMID: 17604940 DOI: 10.1016/j.biopha.2007.05.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2007] [Accepted: 05/02/2007] [Indexed: 12/01/2022] Open
Abstract
(18)F-Fluorodeoxyglucose positron emission tomography (FDG-PET) thyroid incidentalomas are defined abnormal FDG uptake in the thyroid gland found at PET scan performed as part of a staging protocol and follow-up of patients with various kinds of malignancies. In the present study we report two cases of FDG PET thyroid incidentalomas, and review the literature with regard to the meaning of this new category of thyroid "disease". Since the advent of whole body FDG PET scan, a relatively high incidence of cases of thyroid FDG uptake has been reported as an incidental finding as in one of our patient. Focal uptake was found to be more likely associated to a malignant lesion, while a diffuse thyroid uptake to a benign thyroid disease. However, differential diagnosis is difficult, and reported data in literature are somewhat discordant. A focal thyroid uptake of FDG incidentally discovered at PET scan cannot be invariably considered a malignant thyroid nodule, however a prompt and complete work-up including laboratory examinations, ultrasonography and fine needle aspiration cytology, should be obtained to exclude a thyroid carcinoma. On the other hand, patients with a PET finding of diffuse FDG uptake can be considered at low risk of malignancy, being more likely associated to chronic thyroiditis or diffuse thyroid autonomy.
Collapse
Affiliation(s)
- M Salvatori
- Institute of Nuclear Medicine, Università Cattolica del S. Cuore, Rome, Italy
| | | | | | | | | | | | | |
Collapse
|
32
|
Chen W, Li G, Parsons M, Zhuang H, Alavi A. Clinical Significance of Incidental Focal Versus Diffuse Thyroid Uptake on FDG-PET Imaging. PET Clin 2007; 2:321-9. [DOI: 10.1016/j.cpet.2008.04.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
33
|
Bogsrud TV, Karantanis D, Nathan MA, Mullan BP, Wiseman GA, Collins DA, Kasperbauer JL, Strome SE, Reading CC, Hay ID, Lowe VJ. The value of quantifying 18F-FDG uptake in thyroid nodules found incidentally on whole-body PET–CT. Nucl Med Commun 2007; 28:373-81. [PMID: 17414887 DOI: 10.1097/mnm.0b013e3280964eae] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
OBJECTIVE To determine if quantification of [18F]fluorodeoxyglucose (18F-FDG) uptake in a thyroid nodule found incidentally on whole-body 18F-FDG positron emission tomography-computed tomography (PET-CT) can be used to discriminate between malignant and benign aetiology. METHODS A retrospective review of all patients with focally high uptake in the thyroid as an incidental finding on 18F-FDG PET-CT from May 2003 through May 2006. The uptake in the nodules was quantified using the maximum standardized uptake value (SUVmax). The aetiology was determined by cytology and/or ultrasound, or on histopathology. RESULTS Incidental focally high uptake was found in 79/7347 patients (1.1%). In 31/48 patients with adequate follow-up, a benign aetiology was determined. Median SUVmax for the benign group was 5.6, range 2.5-53. Malignancy was confirmed in 15/48 patients. The malignancies were papillary thyroid carcinoma in 12, metastasis from squamous cell carcinoma in one, and lymphoma in two. Median SUVmax for the malignant lesions was 6.4, range 3.5-16. Cytology suspicious for follicular carcinoma was found in 2/48 patients. No statistical difference (P=0.12) was found among the SUVmax between the benign and malignant groups. CONCLUSION Focally high uptake of 18F-FDG in the thyroid as an incidental finding occurred in 1.1% of the patients. Malignancy was confirmed or was suspicious in 17/48 (35%) of the patients that had adequate follow-up. There was no significant difference in the SUVmax between benign and malignant nodules.
Collapse
Affiliation(s)
- Trond V Bogsrud
- Division of Nuclear Medicine, Department of Radiology, Mayo Clinic, Rochester, MN 55905, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Chen YK, Chen YL, Cheng RH, Yeh CL, Lee CC, Hsu CH. The significance of FDG uptake in bilateral thyroid glands. Nucl Med Commun 2007; 28:117-22. [PMID: 17198352 DOI: 10.1097/mnm.0b013e328013eaf7] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
AIM To evaluate the significance of bilateral fluorodeoxyglucose (FDG) uptake in the thyroid glands. METHODS Bilateral thyroid FDG uptake, defined as visualization of thyroid glands, was found in 66 (3.4%) of 1925 subjects who underwent our FDG PET cancer-screening program. Additionally, 16 of the 41 patients with Graves' disease and hyperthyroidism (GD(H)) and six of the 20 subjects with Graves' disease and euthyroidism (GD(E)), who had FDG uptake in thyroid glands, were enrolled in this study. RESULTS Among the 66 subjects, 22 were normal variant, 39 subjects had chronic thyroiditis (35 subjects presented with diffuse goitre and four with multinodular goitre), and five subjects had multinodular goitre (MNG) without chronic thyroiditis. Fourteen of 22 (63.6%) of the subjects with the normal variant had a visual uptake intensity less than that of the liver, while 30 of 39 (76.9%) of the subjects with chronic thyroiditis and 14 of 22 (63.6%) of the subjects with Graves' disease had visual uptake intensity greater than or equal to liver uptake. Two of the five subjects with MNG with focally intense uptake were proven to have thyroid carcinoma. Bilateral loser uptake in thyroids associated with thymus and symmetrical skeletal muscle uptake were found in GD(H). The standard uptake value (SUV) (mean+/-SD) in subjects with chronic thyroiditis (2.76+/-1.24) were higher, while those with GD(H) (1.59+/-0.36) were lower than that of the normal variant (1.99+/-0.63). Subjects with hypothyroidism (3.04+/-1.39) had higher SUV levels than those subjects with euthyroidism (2.44+/-1.11). In addition, patients with GD(H) had lower levels than those with GD(E) (2.0+/-0.38). CONCLUSION (1) Bilateral thyroidal uptake of FDG can be found in normal variants and subjects with various thyroid disorders, showing varieties of uptake patterns. (2) Diffuse intense uptake and higher SUV levels are a clue to a diagnosis of chronic thyroiditis, especially for those with hypothyroidism. (3) Focally intense uptake suggests the possibility of a thyroid carcinoma. (4) Sparse uptake associated with the thymus and symmetrical skeletal muscle uptake and lower SUV level raise the possibility of Graves' disease with hyperthyroidism.
Collapse
Affiliation(s)
- Yen-Kung Chen
- Department of Nuclear Medicine and PET Center, Shin Kong Wu Ho-Su Memorial Hospital, Taipei Medical University, Taipei, Taiwan
| | | | | | | | | | | |
Collapse
|
35
|
Are C, Hsu JF, Schoder H, Shah JP, Larson SM, Shaha AR. FDG-PET Detected Thyroid Incidentalomas: Need for Further Investigation? Ann Surg Oncol 2006; 14:239-47. [PMID: 17024553 DOI: 10.1245/s10434-006-9181-y] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2006] [Revised: 05/21/2006] [Accepted: 05/23/2006] [Indexed: 11/18/2022]
Abstract
BACKGROUND Incidental thyroid abnormalities are increasingly detected in patients undergoing PET scans. The aim of this study was to review our experience with the management of PET detected thyroid incidentalomas in a large single institution series. METHODS All PET scans performed from May 2003 to July 2005 were reviewed and patients with incidental thyroid abnormalities were identified. From this group, patients that underwent further investigation were analyzed. Data relating to PET scan findings, FNA diagnoses, operative details, and histopathology was reviewed. RESULTS In 8,800 patients, 16,300 PET scans were performed of whom 263 patients (2.9% of patients and 1.6% of PET scans) had findings positive for thyroid abnormality. Thyroid malignancy was noted in 42% (24 patients) of the 57 patients that underwent FNA. In the group of 27 patients that were subjected to operative intervention, 74% (20 patients) were noted to have a malignant diagnosis. The final histopathology revealed primary thyroid carcinoma in all these 20 patients (19 patients with papillary carcinoma and one patient with primary thyroid lymphoma). The factors that correlated with an increased risk of malignancy were the presence of physical finding (p = 0.01) and focal (p < 0.01) or unilateral uptake (p < 0.01) on PET scan. The average SUV was not useful in differentiating benign (9.2) from malignant lesions (8.2, p = 0.7). CONCLUSIONS PET detected incidental thyroid abnormalities are rare. In patients with positive PET scan findings and suspicious features, the incidence of primary thyroid malignancy is very high. These patients warrant further investigation followed by possible operative intervention.
Collapse
Affiliation(s)
- Chandrakanth Are
- Department of Surgical Oncology, Memorial Sloan-Kettering Cancer Center, 1233 York Avenue, 16 I, New York, New York, 10021, USA
| | | | | | | | | | | |
Collapse
|
36
|
Chen YK, Chen YL, Liao AC, Shen YY, Kao CH. Elevated 18F-FDG uptake in skeletal muscles and thymus: a clue for the diagnosis of Graves' disease. Nucl Med Commun 2004; 25:115-21. [PMID: 15154698 DOI: 10.1097/00006231-200402000-00004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
AIM The aim of this study was to evaluate the appearance of Graves' disease in whole-body 2-[18F]fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) imaging. SUBJECTS Twenty patients (three men, 17 women; mean age +/- SD, 37.2 +/- 12.1 years) with newly diagnosed Graves' disease without anti-thyroid drug treatment took part in the study. Secondly, a control group, 15 examinees (three men, 12 women; mean age +/- SD, 45.3 +/- 13 years) each with a history of Graves' disease and post-medical treatment were recruited. This group showed normal thyroid function. Finally, a normal group, 32 physical check-up examinees with non-specific medical histories and normal thyroid functions, were recruited. Whole-body FDG PET was performed on all subjects. The intensity of FDG uptake in the thyroid, thymus and muscles region was graded subjectively on a five-point scale. RESULTS Among the 20 patients with Graves' disease, only six (30%) showed thyroid uptake of FDG, 15 (75%) showed thymus uptake of FDG, and up to 19 (95%) showed symmetrical increased uptake of FDG in skeletal muscles. In particular, the skeletal muscle uptake of FDG in the psoas and rectus abdominis muscles was 19/20 (95%) and 12/20 (60%), respectively. In the control group, three of the 15 examinees showed thyroid uptake of FDG. In the normal group, four of the 32 examinees had faintly visualized thyroid uptake of FDG. In thymus and skeletal muscles, there was no substantially increased FDG uptake in control and normal group examinees. CONCLUSIONS In patients with Graves' disease, the thyroid uptake of FDG is not uniformly increased. Symmetrically increased uptake of FDG in the skeletal muscles and thymus is a clue for the diagnosis of Graves' disease. The uptake of FDG in skeletal muscles is more specific in the psoas and rectus abdominis muscles. An increment of muscle FDG uptake may be responsible for the high peripheral glucose utilization seen in Graves' disease.
Collapse
Affiliation(s)
- Yen-Kung Chen
- Department of Nuclear Medicine, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan, ROC.
| | | | | | | | | |
Collapse
|
37
|
Gianoukakis AG, Karam M, Cheema A, Cooper JA. Autonomous thyroid nodules visualized by positron emission tomography with 18F-fluorodeoxyglucose: a case report and review of the literature. Thyroid 2003; 13:395-9. [PMID: 12804108 DOI: 10.1089/105072503321669893] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A 41-year-old white female underwent a positron emission tomography with (18)F-fluorodeoxyglucose (FDG-PET) scan as part of staging follow-up for breast cancer. Focal FDG uptake was noted in the right neck. Further evaluation revealed only thyroid nodules and subclinical hyperthyroidism. A sodium pertechnetate thyroid scan showed two "hot" nodules in the right thyroid lobe corresponding to the focal uptake visualized on FDG-PET scan. Technetium-99m uptake was suppressed in the remaining thyroid gland. The patient underwent a subtotal thyroidectomy. Histopathologic evaluation revealed two hyperplastic nodules in each thyroid lobe. We review the literature with regard to FDG-PET imaging of normal and diseased thyroid tissue.
Collapse
Affiliation(s)
- A G Gianoukakis
- Division of Endocrinology, Albany Medical College, New York, USA.
| | | | | | | |
Collapse
|
38
|
Affiliation(s)
- Yen-Kung Chen
- Department of Nuclear Medicine, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan
| | | |
Collapse
|
39
|
Van den Bruel A, Maes A, De Potter T, Mortelmans L, Drijkoningen M, Van Damme B, Delaere P, Bouillon R. Clinical relevance of thyroid fluorodeoxyglucose-whole body positron emission tomography incidentaloma. J Clin Endocrinol Metab 2002; 87:1517-20. [PMID: 11932274 DOI: 10.1210/jcem.87.4.8371] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Fluorodeoxyglucose (FDG) whole body positron emission tomography (PET) scan is increasingly used in the diagnostic work-up or follow-up of patients. In these conditions, positive PET scans with unexpected hot spots within the thyroid region could be defined as thyroid FDG-PET incidentaloma (in analogy with unexpected sonographic thyroid nodules). We describe eight consecutive patients referred to the endocrine department because of thyroid "hot spots," incidentally detected by whole body FDG-PET scan (September 1999 to March 2001). Using ultrasound, fine needle aspiration cytology (FNAC), and histology reports, we tried to identify the pathology underlying thyroid FDG-PET incidentaloma. FNAC showed an indication for surgery in all patients. Surgery has been performed in 7 patients. Malignancy was correctly identified in five patients: two medullary thyroid carcinomas, one with lymph node invasion, and three papillary thyroid carcinomas with invasion through the thyroid capsule in two of the PTC cases. In two patients with a positive FDG-PET scan, FNAC pointed to follicular neoplasms, and final histology reports showed follicular adenoma. In the remaining patient, FNAC revealed a follicular lesion, but surgery has not yet been performed. In conclusion, a small series of consecutive thyroid FDG-PET incidentaloma cases is presented and suggests a high rate of clinically relevant malignancies.
Collapse
Affiliation(s)
- Annick Van den Bruel
- Laboratory and Clinic of Experimental Medicine and Endocrinology, Universitaire Ziekenhuizen Gasthuisberg, B-3000 Leuven, Belgium
| | | | | | | | | | | | | | | |
Collapse
|
40
|
Ramos CD, Chisin R, Yeung HW, Larson SM, Macapinlac HA. Incidental focal thyroid uptake on FDG positron emission tomographic scans may represent a second primary tumor. Clin Nucl Med 2001; 26:193-7. [PMID: 11245108 DOI: 10.1097/00003072-200103000-00002] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE This article discusses the value of incidental thyroid uptake of fluorodeoxyglucose (FDG) on whole-body positron emission tomography (PET) scans performed in patients with cancer. This issue has been reported diversely in the literature. MATERIALS AND METHODS Whole-body PET scans of four patients with cancer (two of them women; age, 49 to 78 years) in whom focal thyroid uptake was visualized and subsequently correlated with thyroid carcinoma based on cytologic or histopathologic data were reviewed. The clinical outcomes of these patients were analyzed retrospectively. Maximum and average standardized uptake values (SUVs) of thyroid accumulation were recalculated in all patients. RESULTS Two of the four patients referred for FDG PET scans had lung adenocarcinomas, one had prostate carcinoma, and one had an unknown primary tumor. Focal thyroid uptake was visualized, with maximum and average SUVs ranging from 3.7 and 2.3 to 53 and 34, respectively. These findings were correlated with cytologic (two patients) or histopathologic data (two patients) that indicated thyroid carcinoma. In two patients, their treatment was changed and total thyroidectomy was performed; in one of them the SUVs of the focal thyroid accumulation (maximum and average values of 7.9 and 4.8, respectively) were less than the cutoff values for thyroid cancer noted in the literature. The clinical condition of the other two patients did not permit additional investigation or treatment for thyroid carcinoma. CONCLUSION Increased focal thyroid uptake on whole-body FDG PET scans should not be overlooked, even when it is not marked, and should prompt further investigation to rule out cancer.
Collapse
Affiliation(s)
- C D Ramos
- Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, New York, USA.
| | | | | | | | | |
Collapse
|
41
|
Abstract
FDG-PET imaging in neck oncology has a definite clinical impact in the post-therapy setting, assisting in the management of thyroid cancers and SCC of the neck. Quantitation of FDG uptake in suspicious areas may be helpful but should be regarded cautiously. Overall, wider incorporation of FDG imaging in clinical routine depends also on cost availability issues of FDG and of imaging devices. Dual-coincidence scanners for FDG imaging are much cheaper than dedicated PET scanners and are installed in growing numbers in many centers. These devices have inferior sensitivity; however, series published with these scanners produce encouraging results. Easier and more acceptable clinical application will also be facilitated by the systematic use of coregistration with anatomic images. Both prerequisites might be fulfilled by the emergence on the market of a gamma camera-mounted anatomic X-ray tomograph, which in addition to dual-coincidence scintigraphic imaging provides radiographic images of comparable quality to third-generation CT systems. This type of hybrid gamma camera-CT scanner has great potential in a region of complex anatomy, such as the head and neck.
Collapse
Affiliation(s)
- R Chisin
- Department of Medical Biophysics and Nuclear Medicine, Hadassah Hebrew University Hospital, Jerusalem, Israel.
| | | |
Collapse
|