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Xu L, Huang G, Wang Y, Huang G, Liu J, Chen R. 2-[ 18F]FDG PET-based quantification of lymph node metabolic heterogeneity for predicting lymph node metastasis in patients with colorectal cancer. Eur J Nucl Med Mol Imaging 2024; 51:1729-1740. [PMID: 38150017 DOI: 10.1007/s00259-023-06578-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Accepted: 12/15/2023] [Indexed: 12/28/2023]
Abstract
BACKGROUND AND PURPOSE The pre-surgical estimation of lymph node (LN) metastasis in colorectal cancer (CRC) poses a significant diagnostic predicament. The associations between LN morphology, density, and metabolic heterogeneity and LN metastasis status in CRCs have been seldomly examined through the lens of radiomics. This research aimed to assess 2-[18F]FDG PET-based quantification of intratumoral metabolic heterogeneity for predicting lymph node metastasis in patients with colorectal cancer. MATERIALS AND METHODS The construction of the model utilized data from 264 CRC patients, all of whom underwent preoperative 2-[18F]FDG PET/CT. Radiomic features were extracted from PET and CT images of LNs. Least absolute shrinkage and selection operator (LASSO) regression was implemented for selecting pertinent imaging features with a tenfold cross-validation. The predictive accuracy for LN metastasis status was juxtaposed against traditional methodologies (comprising CT-reported LN status and PET/CT-reported LN status) by deploying the receiver operating characteristic (ROC) curve analysis. The radiomics signature was evaluated based on discrimination, calibration, and clinical utility parameters. The model was further subjected to validation using an independent cohort of 132 patients from the period of January 2012 to June 2020. RESULTS The radiomics model was composed of eight significant radiomic features (five from PET and three from CT), encapsulating metabolic and density heterogeneity. The radiomics signature (area under the curve (AUC), 0.908) showcased a significantly superior performance compared to CT-reported LN status (AUC, 0.563, P < 0.001) and PET/CT-reported LN status (AUC, 0.64, P < 0.001) for predicting LN-positive or LN-negative status. The radiomics signature (AUC, 0.885) also showcased a significantly superior performance compared to CT-reported LN status (AUC, 0.587, P < 0.001) and PET/CT-reported LN status (AUC, 0.621, P < 0.001) to identify N1 and N2. This signature maintained its independence from clinical risk factors and exhibited robustness in the validation test set. Decision curve analysis attested to the clinical utility of the radiomics signature. CONCLUSIONS The radiomics signature based on 2-[18F]FDG PET/CT, which derived image features directly from LNs irrespective of clinical risk factors, displayed enhanced diagnostic performance compared to conventional CT or PET/CT-reported LN status. This allows for the identification of pre-surgical LN metastasis status and facilitates a patient-specific prediction of LN metastasis status in CRC patients.
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Affiliation(s)
- Lian Xu
- Department of Nuclear Medicine, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, 160 Pujian Road, Shanghai, 200000, China
| | - Gan Huang
- Department of Nuclear Medicine, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, 160 Pujian Road, Shanghai, 200000, China
| | - Yining Wang
- Department of Nuclear Medicine, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, 160 Pujian Road, Shanghai, 200000, China
| | - Gang Huang
- Department of Nuclear Medicine, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, 160 Pujian Road, Shanghai, 200000, China
| | - Jianjun Liu
- Department of Nuclear Medicine, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, 160 Pujian Road, Shanghai, 200000, China.
| | - Ruohua Chen
- Department of Nuclear Medicine, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, 160 Pujian Road, Shanghai, 200000, China.
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Chantadisai M, Wongwijitsook J, Ritlumlert N, Rakvongthai Y. Combined clinical variable and radiomics of post-treatment total body scan for prediction of successful I-131 ablation in low-risk papillary thyroid carcinoma patients. Sci Rep 2024; 14:5001. [PMID: 38424177 PMCID: PMC10904821 DOI: 10.1038/s41598-024-55755-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 02/27/2024] [Indexed: 03/02/2024] Open
Abstract
To explore the feasibility of combined radiomics of post-treatment I-131 total body scan (TBS) and clinical parameter to predict successful ablation in low-risk papillary thyroid carcinoma (PTC) patients. Data of low-risk PTC patients who underwent total/near total thyroidectomy and I-131 ablation 30 mCi between April 2015 and July 2021 were retrospectively reviewed. The clinical factors studied included age, sex, and pre-ablative serum thyroglobulin (Tg). Radiomic features were extracted via PyRadiomics, and radiomic feature selection was performed. The predictive performance for successful ablation of the clinical parameter, radiomic, and combined models (radiomics combined with clinical parameter) was calculated using the area under the receiver operating characteristic curve (AUC). One hundred and thirty patients were included. Successful ablation was achieved in 77 patients (59.2%). The mean pre-ablative Tg in the unsuccessful group (15.50 ± 18.04 ng/ml) was statistically significantly higher than those in the successful ablation group (7.12 ± 7.15 ng/ml). The clinical parameter, radiomic, and combined models produced AUCs of 0.66, 0.77, and 0.87 in the training sets, and 0.65, 0.69, and 0.78 in the validation sets, respectively. The combined model produced a significantly higher AUC than that of the clinical parameter (p < 0.05). Radiomic analysis of the post-treatment TBS combined with pre-ablative serum Tg showed a significant improvement in the predictive performance of successful ablation in low-risk PTC patients compared to the use of clinical parameter alone.Thai Clinical Trials Registry TCTR identification number is TCTR20230816004 ( https://www.thaiclinicaltrials.org/show/TCTR20230816004 ).
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Affiliation(s)
- Maythinee Chantadisai
- Division of Nuclear Medicine, Department of Radiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
- Division of Nuclear Medicine, Department of Radiology, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, Thailand.
| | - Jirarot Wongwijitsook
- Division of Nuclear Medicine, Department of Radiology, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, Thailand
- Division of Nuclear Medicine, Department of Radiology, Surin Hospital, Surin, Thailand
| | - Napat Ritlumlert
- Chulalongkorn University Biomedical Imaging Group, Department of Radiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- Biomedical Engineering Program, Faculty of Engineering, Chulalongkorn University, Bangkok, Thailand
- School of Radiological Technology, Faculty of Health Science Technology, Chulabhorn Royal Academy, Bangkok, Thailand
| | - Yothin Rakvongthai
- Division of Nuclear Medicine, Department of Radiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- Chulalongkorn University Biomedical Imaging Group, Department of Radiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
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Dondi F, Gatta R, Treglia G, Piccardo A, Albano D, Camoni L, Gatta E, Cavadini M, Cappelli C, Bertagna F. Application of radiomics and machine learning to thyroid diseases in nuclear medicine: a systematic review. Rev Endocr Metab Disord 2024; 25:175-186. [PMID: 37434097 PMCID: PMC10808150 DOI: 10.1007/s11154-023-09822-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/30/2023] [Indexed: 07/13/2023]
Abstract
BACKGROUND In the last years growing evidences on the role of radiomics and machine learning (ML) applied to different nuclear medicine imaging modalities for the assessment of thyroid diseases are starting to emerge. The aim of this systematic review was therefore to analyze the diagnostic performances of these technologies in this setting. METHODS A wide literature search of the PubMed/MEDLINE, Scopus and Web of Science databases was made in order to find relevant published articles about the role of radiomics or ML on nuclear medicine imaging for the evaluation of different thyroid diseases. RESULTS Seventeen studies were included in the systematic review. Radiomics and ML were applied for assessment of thyroid incidentalomas at 18 F-FDG PET, evaluation of cytologically indeterminate thyroid nodules, assessment of thyroid cancer and classification of thyroid diseases using nuclear medicine techniques. CONCLUSION Despite some intrinsic limitations of radiomics and ML may have affect the results of this review, these technologies seem to have a promising role in the assessment of thyroid diseases. Validation of preliminary findings in multicentric studies is needed to translate radiomics and ML approaches in the clinical setting.
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Affiliation(s)
- Francesco Dondi
- Nuclear Medicine, ASST Spedali Civili di Brescia, P.le Spedali Civili, 1, Brescia, 25123, Italy
| | - Roberto Gatta
- Dipartimento di Scienze Cliniche e Sperimentali, Università degli Studi di Brescia, Brescia, Italy
| | - Giorgio Treglia
- Clinic of Nuclear Medicine, Imaging Institute of Southern Switzerland, Ente Ospedaliero Cantonale, Bellinzona, Switzerland
- Department of Nuclear Medicine and Molecular Imaging, Lausanne University Hospital, University of Lausanne, Lausanne, Switzerland
- Faculty of Biomedical Sciences, Università della Svizzera italiana, Lugano, Switzerland
| | | | - Domenico Albano
- Nuclear Medicine, ASST Spedali Civili di Brescia and Università degli Studi di Brescia, Brescia, Italy
| | - Luca Camoni
- Nuclear Medicine, ASST Spedali Civili di Brescia, P.le Spedali Civili, 1, Brescia, 25123, Italy
| | - Elisa Gatta
- Unit of Endocrinology and Metabolism, ASST Spedali Civili di Brescia and Università degli Studi di Brescia, Brescia, Italy
| | - Maria Cavadini
- Unit of Endocrinology and Metabolism, ASST Spedali Civili di Brescia and Università degli Studi di Brescia, Brescia, Italy
| | - Carlo Cappelli
- Unit of Endocrinology and Metabolism, ASST Spedali Civili di Brescia and Università degli Studi di Brescia, Brescia, Italy
| | - Francesco Bertagna
- Nuclear Medicine, ASST Spedali Civili di Brescia, P.le Spedali Civili, 1, Brescia, 25123, Italy.
- Nuclear Medicine, ASST Spedali Civili di Brescia and Università degli Studi di Brescia, Brescia, Italy.
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Lohmann P, Bundschuh RA, Miederer I, Mottaghy FM, Langen KJ, Galldiks N. Clinical Applications of Radiomics in Nuclear Medicine. Nuklearmedizin 2023; 62:354-360. [PMID: 37935406 DOI: 10.1055/a-2191-3271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2023]
Abstract
Radiomics is an emerging field of artificial intelligence that focuses on the extraction and analysis of quantitative features such as intensity, shape, texture and spatial relationships from medical images. These features, often imperceptible to the human eye, can reveal complex patterns and biological insights. They can also be combined with clinical data to create predictive models using machine learning to improve disease characterization in nuclear medicine. This review article examines the current state of radiomics in nuclear medicine and shows its potential to improve patient care. Selected clinical applications for diseases such as cancer, neurodegenerative diseases, cardiovascular problems and thyroid diseases are examined. The article concludes with a brief classification in terms of future perspectives and strategies for linking research findings to clinical practice.
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Affiliation(s)
- Philipp Lohmann
- Institute of Neuroscience and Medicine (INM-3/-4), Forschungszentrum Jülich GmbH, Jülich, Germany
| | | | - Isabelle Miederer
- Department of Nuclear Medicine, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Felix M Mottaghy
- Department of Nuclear Medicine, University Hospital RWTH Aachen, Aachen, Germany
- Center for Integrated Oncology (CIO), Universities of Aachen, Bonn, Cologne, and Duesseldorf, Germany
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Karl Josef Langen
- Institute of Neuroscience and Medicine (INM-3/-4), Forschungszentrum Jülich GmbH, Jülich, Germany
- Department of Nuclear Medicine, University Hospital RWTH Aachen, Aachen, Germany
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Norbert Galldiks
- Faculty of Medicine and University Hospital Cologne, Department of Neurology, University of Cologne, Cologne, Germany
- Institute of Neuroscience and Medicine (INM-3/-4), Forschungszentrum Jülich GmbH, Jülich, Germany
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
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Canpolat AG, Taşkın DG, Deryol HY, Korkmaz FN, Erdoğan MF. Should we reconsider high-risk features in thyroid ultrasonography? REVISTA DA ASSOCIACAO MEDICA BRASILEIRA (1992) 2023; 69:e20230820. [PMID: 37909623 PMCID: PMC10610763 DOI: 10.1590/1806-9282.20230820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Accepted: 08/15/2023] [Indexed: 11/03/2023]
Abstract
OBJECTIVE Round shape is generally considered to reduce the risk of malignancy according to recent guidelines. On the contrary, according to some reports, spherically shaped thyroid nodules are associated with a higher risk of malignancy. Thus, we aimed to evaluate the malignancy risk of solid round isoechoic nodules detected at thyroid ultrasonography and compare it with that of solid ovoid isoechoic nodules. METHODS Between 2017 and 2022, solitary solid round isoechoic nodules with diameters ³10 and £25 mm at thyroid ultrasonography were retrospectively selected and enrolled in the study. Age, size, nodule volume, serum thyrotropin levels, thyroid antibody levels, and cytopathological and histopathological results were recorded. RESULTS A total of 457 solitary solid isoechoechoic nodules from 457 patients (262 females and 195 males; median age, 59 [31-70] years) were selected, of which 203 were solid round isoechoic nodules, and 254 were solid ovoid isoechoic nodules. A total of 54 surgical operations were performed on 457 nodules, and 31 of them resulted in malignancy. From the 31 malignant results, 25 originated from solid round isoechoic nodules and the remaining 6 originated from solid ovoid isoechoic nodules (p<0.025). CONCLUSION We found that round nodules have higher malignancy rates than ovoid nodules. We think that ultrasonographic risk stratification systems used to target the most suitable nodules for the necessary biopsies can be dynamically updated, and sphericity can be added as a parameter in patient-based decision-making.
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Affiliation(s)
- Asena Gökçay Canpolat
- Ankara University, School of Medicine, Department of Endocrinology and Metabolism – Ankara, Turkey
| | - Dursun Göktürk Taşkın
- Ankara University, School of Medicine, Department of Internal Medicine – Ankara, Turkey
| | - Hilal Yıldırım Deryol
- Ankara Training and Research Hospital, Department of Endocrinology and Metabolism – Ankara, Turkey
| | - Fatma Nur Korkmaz
- Ankara University, School of Medicine, Department of Endocrinology and Metabolism – Ankara, Turkey
| | - Murat Faik Erdoğan
- Ankara University, School of Medicine, Department of Endocrinology and Metabolism – Ankara, Turkey
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Ko WS, Kim SJ. Prediction of Malignant Thyroid Nodules Using 18 F-FDG PET/CT-Based Radiomics Features in Thyroid Incidentalomas. Clin Nucl Med 2023; 48:497-504. [PMID: 37001129 DOI: 10.1097/rlu.0000000000004637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
Abstract
OBJECTIVE The purpose of the current study was to evaluate the diagnostic performances of 18 F-FDG PET/CT-based radiomics features for prediction of malignant thyroid nodules (TNs) in thyroid incidentaloma (TI). METHODS PubMed, Cochrane database, and EMBASE database, from the earliest available date of indexing through December 31, 2022, were searched for studies evaluating diagnostic performance of 18 F-FDG PET/CT-based radiomics features for prediction of malignant TNs in TI. We determined the sensitivities and specificities across studies, calculated positive and negative likelihood ratios (LRs; positive and negative LRs), and estimated pooled area under the curve. RESULTS Across 5 studies (518 patients), the pooled sensitivity of 18 F-FDG PET/CT was 0.77 (95% confidence interval [CI], 0.67-0.84), and a pooled specificity was 0.67. Likelihood ratio syntheses gave an overall positive LR of 2.3 (95% CI, 1.5-3.6) and negative LR of 0.35 (95% CI, 0.26-0.47). The pooled diagnostic odds ratio was 7 (95% CI, 4-12). The pooled area under the curve of fixed effects was 0.763 (95% CI, 0.736-0.791), and that of random effects was 0.763 (95% CI, 0.721-0.805). CONCLUSION 18 F-FDG PET/CT-based radiomics features showed a good diagnostic performance for prediction of malignant TNs in TI.
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Affiliation(s)
- Woo Seog Ko
- From the Department of Internal Medicine, Pusan National University Hospital, Busan
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Abou Karam G, Malhotra A. PET/CT May Assist in Avoiding Pointless Thyroidectomy in Indeterminate Thyroid Nodules: A Narrative Review. Cancers (Basel) 2023; 15:cancers15051547. [PMID: 36900338 PMCID: PMC10000406 DOI: 10.3390/cancers15051547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Revised: 02/23/2023] [Accepted: 02/26/2023] [Indexed: 03/05/2023] Open
Abstract
Indeterminate thyroid nodules (ITN) are commonly encountered among the general population, with a malignancy rate of 10 to 40%. However, many patients may be overtreated with futile surgery for benign ITN. To avoid unnecessary surgery, PET/CT scan is a possible alternative to help differentiate between benign and malignant ITN. In this narrative review, the major results and limitations of the most recent studies on PET/CT efficacy (from PET/CT visual assessment to quantitative PET parameters and recent radiomic features analysis) and on cost-effectiveness (compared to other alternatives (such as surgery)) are presented. PET/CT can reduce futile surgery with visual assessment (around 40%; if ITN ≥ 10 mm). Moreover, PET/CT conventional parameters and radiomic features extracted from PET/CT imaging can be associated together in a predictive model to rule out malignancy in ITN, with a high NPV (96%) when certain criteria are met. Even though promising results were obtained in these recent PET/CT studies, further studies are needed to enable PET/CT to become the definitive diagnostic tool once a thyroid nodule is identified as indeterminate.
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Affiliation(s)
- Gaby Abou Karam
- Section of Neuroradiology, Department of Radiology and Biomedical Imaging, Yale School of Medicine, 333 Cedar St., New Haven, CT 06510, USA
| | - Ajay Malhotra
- Section of Neuroradiology, Department of Radiology and Biomedical Imaging, Yale School of Medicine, 333 Cedar St., New Haven, CT 06510, USA
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, 789 Howard Ave, New Haven, CT 06519, USA
- Correspondence: ; Tel.: +1-(203)-785-5102; Fax: +1-(203)-737-1077
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Meng Y, Sun J, Zhang G, Yu T, Piao H. Imaging glucose metabolism to reveal tumor progression. Front Physiol 2023; 14:1103354. [PMID: 36818450 PMCID: PMC9932271 DOI: 10.3389/fphys.2023.1103354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Accepted: 01/20/2023] [Indexed: 02/05/2023] Open
Abstract
Purpose: To analyze and review the progress of glucose metabolism-based molecular imaging in detecting tumors to guide clinicians for new management strategies. Summary: When metabolic abnormalities occur, termed the Warburg effect, it simultaneously enables excessive cell proliferation and inhibits cell apoptosis. Molecular imaging technology combines molecular biology and cell probe technology to visualize, characterize, and quantify processes at cellular and subcellular levels in vivo. Modern instruments, including molecular biochemistry, data processing, nanotechnology, and image processing, use molecular probes to perform real-time, non-invasive imaging of molecular and cellular events in living organisms. Conclusion: Molecular imaging is a non-invasive method for live detection, dynamic observation, and quantitative assessment of tumor glucose metabolism. It enables in-depth examination of the connection between the tumor microenvironment and tumor growth, providing a reliable assessment technique for scientific and clinical research. This new technique will facilitate the translation of fundamental research into clinical practice.
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Affiliation(s)
- Yiming Meng
- Central Laboratory, Liaoning Cancer Hospital & Institute, Cancer Hospital of China Medical University, Shenyang, China
| | - Jing Sun
- Central Laboratory, Liaoning Cancer Hospital & Institute, Cancer Hospital of China Medical University, Shenyang, China
| | - Guirong Zhang
- Central Laboratory, Liaoning Cancer Hospital & Institute, Cancer Hospital of China Medical University, Shenyang, China
| | - Tao Yu
- Department of Medical Image, Liaoning Cancer Hospital & Institute, Cancer Hospital of China Medical University, Shenyang, China,*Correspondence: Tao Yu, ; Haozhe Piao,
| | - Haozhe Piao
- Department of Neurosurgery, Liaoning Cancer Hospital & Institute, Cancer Hospital of China Medical University, Shenyang, China,*Correspondence: Tao Yu, ; Haozhe Piao,
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9
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Lee H, Hwang KH. Significance of incidental focal fluorine-18 fluorodeoxyglucose uptake in colon/rectum, thyroid, and prostate: With a brief literature review. World J Clin Cases 2022; 10:12532-12542. [PMID: 36579086 PMCID: PMC9791515 DOI: 10.12998/wjcc.v10.i34.12532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 08/10/2022] [Accepted: 11/08/2022] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT), a functional imaging method, is usually performed on the entire torso, and regions of unexpected suspicious focal hypermetabolism are not infrequently observed. Among the regions, colon, thyroid, and prostate were found to be the common organs in a recent umbrella review. Some studies reported that a high rate of malignancy was shown in incidentally identified focal hypermetabolic regions and suggested that further examinations should not be ignored.
AIM To investigate the malignancy rate of incidental focal FDG uptake, useful PET parameters and their cutoffs in discrimination between malignant and benign lesions.
METHODS Retrospectively, the final reports of 16510 F-18 FDG PET/CT scans performed at our hospital between January 2016 and March 2022 were reviewed to identify incidentally observed FDG uptake in the colon/rectum, thyroid, and prostate. The scans of patients with current or prior malignancies at each corresponding location, without the final reports of histopathology or colonoscopy (for colon and rectum) for the corresponding hypermetabolic regions, or with diffuse (not focal) hypermetabolism were excluded. Finally, 88 regions of focal colorectal hypermetabolism in 85 patients (48 men and 37 women with mean age 67.0 ± 13.4 years and 63.4 ± 15.8 years, respectively), 48 focal thyroid uptakes in 48 patients (12 men and 36 women with mean age 62.2 ± 13.1 years and 60.8 ± 12.4 years, respectively), and 39 focal prostate uptakes in 39 patients (mean age 71.8 ± 7.5 years) were eligible for this study. For those unexpected focal hypermetabolic regions, rates of malignancy were calculated, PET parameters, such as standardized uptake value (SUV), capable of distinguishing between malignant and benign lesions were investigated, and the cutoffs of those PET parameters were determined by plotting receiver operating characteristic curves.
RESULTS In the colon and rectum, 29.5% (26/88) were malignant and 33.0% (29/88) were premalignant lesions. Both SUVmax and SUVpeak differentiated malignant/premalignant from benign lesions, however, no parameters could distinguish malignant from premalignant lesions. Higher area under the curve was shown with SUVmax (0.752, 95%CI: 0.649-0.856, P < 0.001) and the cutoff was 7.6. In the thyroid, 60.4% (29/48) were malignant. The majority were well-differentiated thyroid cancers (89.7%, 26/29). The results of BRAF mutation tests were available for 20 of the 26 well-differentiated thyroid cancers and all 20 had the mutation. Solely SUVmax differentiated malignant from benign lesions and the cutoff was 6.9. In the prostate, 56.4% (22/39) were malignant. Only SUVmax differentiated malignant from benign lesions and the cutoff was 3.8. Overall, among the 175 focal hypermetabolic regions, 60.6% (106/175) were proven to be malignant and premalignant (in colon and rectum) lesions.
CONCLUSION Approximately 60% of the incidentally observed focal F-18 FDG uptake in the colon/rectum, thyroid, and prostate were found to be malignant. Of the several PET parameters, SUVmax was superior to others in distinguishing between malignant/premalignant and benign lesions. Based on these findings, incidental focal hypermetabolism should not be ignored and lead physicians to conduct further investigations with greater confidence.
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Affiliation(s)
- Haejun Lee
- Department of Nuclear Medicine, Gachon University College of Medicine, Gil Medical Center, Incheon 21565, South Korea
| | - Kyung-Hoon Hwang
- Department of Nuclear Medicine, Gachon University College of Medicine, Gil Medical Center, Incheon 21565, South Korea
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An 18F-FDG PET/CT radiomics nomogram for differentiation of high-risk and non-high-risk patients of the International Neuroblastoma Risk Group Staging System. Eur J Radiol 2022; 154:110444. [DOI: 10.1016/j.ejrad.2022.110444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 06/28/2022] [Accepted: 07/18/2022] [Indexed: 11/22/2022]
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Giovanella L, Petranović Ovčariček P. Functional and molecular thyroid imaging. 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; 66:86-92. [PMID: 35166094 DOI: 10.23736/s1824-4785.22.03428-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Nuclear medicine methods were introduced in the 1940s for thyroid disease diagnosis and therapy. They is still a crucial part of thyroid nodules work-up. Thyroid imaging with iodine or iodine-analog isotopes is widely employed in patients with thyrotoxicosis and remains the only examination able to prove the presence of autonomously functioning thyroid tissue, which excludes malignancy with a high probability. In addition, technetium-99m-methoxyisobutylisonitrile ([99mTc]Tc-MIBI) scintigraphy and positron emission tomography/computed tomography (PET/CT) with 18F-fluoro-2-deoxy-d-glucose ([18F]FDG) are able to avoid unnecessary surgical procedures for cytologically inconclusive thyroid nodules, as confirmed by meta-analysis and cost-effectiveness studies. All considered thyroid molecular imaging allows functional characterization of different thyroid diseases, even before clinical symptoms become manifest, and remains integral to the management of such conditions. This paper summarizes main concepts of thyroid scintigraphy and its clinical use. In addition, it elaborates development of thyroid scintigraphy, as well as thyroid molecular imaging in patients with thyroid nodules and thyrotoxicosis.
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Affiliation(s)
- Luca Giovanella
- Clinic for Nuclear Medicine and Molecular Imaging, Imaging Institute of Southern Switzerland, Ente Ospedaliero Cantonale - EOC, Bellinzona, Switzerland -
- Clinic for Nuclear Medicine and Interdisciplinary Thyroid Center, University Hospital of Zurich, University of Zurich, Zurich, Switzerland -
| | - Petra Petranović Ovčariček
- Department of Oncology and Nuclear Medicine, University Hospital Center Sestre Milosrdnice, Zagreb, Croatia
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Giovanella L, Avram AM, Ovčariček PP, Clerc J. Thyroid functional and molecular imaging. Presse Med 2022; 51:104116. [PMID: 35124101 DOI: 10.1016/j.lpm.2022.104116] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 12/02/2021] [Accepted: 01/28/2022] [Indexed: 12/16/2022] Open
Abstract
Radioiodine uptake (RAIU) test with iodine-123 (Na[123I]I) or iodine-131 (Na[131I]I) enables accurate evaluation and quantification of iodine uptake and kinetics within thyroid cells. Thyroid Scintigraphy (TS) employing Na[123I]I or 99mTc-pertechnetate (Na[99mTc]TcO4) provides information regarding the function and topographical distribution of thyroid cells activity, including detection and localization of ectopic thyroid tissue. Destructive thyrotoxicosis is characterized by low RAIU with scintigraphically reduced radiotracer activity in the thyroid tissue, while productive thyrotoxicosis (i.e. hyperthyroidism "stricto sensu") is characterized by high RAIU with scintigraphically diffuse (i.e. Graves' Disease, GD and diffuse thyroid autonomy) or focal (i.e. autonomously functioning thyroid nodules, AFTN) overactivity. Accordingly, RAIU and/or TS are widely used to differentiate different causes of thyrotoxicosis. In addition, several radiopharmaceuticals are also available to help differentiate benign from malignant thyroid nodules and inform clinical decision-making: scintigraphic identification of AFTNs obviate fine-needle aspiration (FNA) biopsy, and [99mTc]Tc-hexakis-(2‑methoxy-2-isobutyl isonitrile ([99mTc]Tc-MIBI) and/or 18F-fluoro-d-glucose ([18F]FDG) may complement the work-up of cytologically indeterminate "cold" nodules for reducing the need for diagnostic lobectomies/thyroidectomies. Finally, RAIU studies are also useful for calculating the administered therapeutic activity of Na[131I]I to treat hyperthyroidism and euthyroid multinodular goiter. All considered, thyroid molecular imaging allows functional characterization of different thyroid diseases, even before clinical symptoms become manifest, and remains integral to the management of such conditions. Our present paper summarizes basic concepts, clinical applications, and potential developments of thyroid molecular imaging in patients affected by thyrotoxicosis and thyroid nodules.
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Affiliation(s)
- Luca Giovanella
- Clinic for Nuclear Medicine and Molecular Imaging, Imaging Institute of Southern Switzerland, Ente Ospedaliero Cantonale, Bellinzona, Switzerland; Clinic for Nuclear Medicine, University Hospital and University of Zurich, Zurich, Switzerland.
| | - Anca M Avram
- Division of Nuclear Medicine, Department of Radiology, University of Michigan, Ann Arbor, MI, USA; Division of Endocrinology, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Petra Petranović Ovčariček
- Department of Oncology and Nuclear Medicine, University Hospital Center "Sestre milosrdnice", Zagreb, Croatia
| | - Jerome Clerc
- Department of Nuclear Medicine, Cochin Hospital, Assistance Publique Hôpitaux de Paris, DMU Imagina, University of Paris France
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Morland D, Triumbari EKA, Boldrini L, Gatta R, Pizzuto D, Annunziata S. Radiomics in Oncological PET Imaging: A Systematic Review—Part 1, Supradiaphragmatic Cancers. Diagnostics (Basel) 2022; 12:diagnostics12061329. [PMID: 35741138 PMCID: PMC9221970 DOI: 10.3390/diagnostics12061329] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 05/25/2022] [Accepted: 05/26/2022] [Indexed: 12/10/2022] Open
Abstract
Radiomics is an upcoming field in nuclear oncology, both promising and technically challenging. To summarize the already undertaken work on supradiaphragmatic neoplasia and assess its quality, we performed a literature search in the PubMed database up to 18 February 2022. Inclusion criteria were: studies based on human data; at least one specified tumor type; supradiaphragmatic malignancy; performing radiomics on PET imaging. Exclusion criteria were: studies only based on phantom or animal data; technical articles without a clinically oriented question; fewer than 30 patients in the training cohort. A review database containing PMID, year of publication, cancer type, and quality criteria (number of patients, retrospective or prospective nature, independent validation cohort) was constructed. A total of 220 studies met the inclusion criteria. Among them, 119 (54.1%) studies included more than 100 patients, 21 studies (9.5%) were based on prospectively acquired data, and 91 (41.4%) used an independent validation set. Most studies focused on prognostic and treatment response objectives. Because the textural parameters and methods employed are very different from one article to another, it is complicated to aggregate and compare articles. New contributions and radiomics guidelines tend to help improving quality of the reported studies over the years.
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Affiliation(s)
- David Morland
- Nuclear Medicine Unit, TracerGLab, Department of Radiology, Radiotherapy and Hematology, Fondazione Policlinico Universitario A. Gemelli, IRCCS, 00168 Rome, Italy; (E.K.A.T.); (D.P.); (S.A.)
- Service de Médecine Nucléaire, Institut Godinot, 51100 Reims, France
- Laboratoire de Biophysique, UFR de Médecine, Université de Reims Champagne-Ardenne, 51100 Reims, France
- CReSTIC (Centre de Recherche en Sciences et Technologies de l’Information et de la Communication), EA 3804, Université de Reims Champagne-Ardenne, 51100 Reims, France
- Correspondence:
| | - Elizabeth Katherine Anna Triumbari
- Nuclear Medicine Unit, TracerGLab, Department of Radiology, Radiotherapy and Hematology, Fondazione Policlinico Universitario A. Gemelli, IRCCS, 00168 Rome, Italy; (E.K.A.T.); (D.P.); (S.A.)
| | - Luca Boldrini
- Radiotherapy Unit, Radiomics, Department of Radiology, Radiotherapy and Hematology, Fondazione Policlinico Universitario A. Gemelli, IRCCS, 00168 Rome, Italy; (L.B.); (R.G.)
| | - Roberto Gatta
- Radiotherapy Unit, Radiomics, Department of Radiology, Radiotherapy and Hematology, Fondazione Policlinico Universitario A. Gemelli, IRCCS, 00168 Rome, Italy; (L.B.); (R.G.)
- Department of Clinical and Experimental Sciences, University of Brescia, 25121 Brescia, Italy
- Department of Oncology, Lausanne University Hospital, 1011 Lausanne, Switzerland
| | - Daniele Pizzuto
- Nuclear Medicine Unit, TracerGLab, Department of Radiology, Radiotherapy and Hematology, Fondazione Policlinico Universitario A. Gemelli, IRCCS, 00168 Rome, Italy; (E.K.A.T.); (D.P.); (S.A.)
| | - Salvatore Annunziata
- Nuclear Medicine Unit, TracerGLab, Department of Radiology, Radiotherapy and Hematology, Fondazione Policlinico Universitario A. Gemelli, IRCCS, 00168 Rome, Italy; (E.K.A.T.); (D.P.); (S.A.)
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14
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Gherghe M, Lazar AM, Mutuleanu MD, Stanciu AE, Martin S. Radiomics Analysis of [18F]FDG PET/CT Thyroid Incidentalomas: How Can It Improve Patients’ Clinical Management? A Systematic Review from the Literature. Diagnostics (Basel) 2022; 12:diagnostics12020471. [PMID: 35204561 PMCID: PMC8870948 DOI: 10.3390/diagnostics12020471] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 02/07/2022] [Accepted: 02/09/2022] [Indexed: 01/01/2023] Open
Abstract
Background: We performed a systematic review of the literature to provide an overview of the application of PET-based radiomics of [18F]FDG-avid thyroid incidentalomas and to discuss the additional value of PET volumetric parameters and radiomic features over clinical data. Methods: The most relevant databases were explored using an algorithm constructed based on a combination of terms related to our subject and English-language articles published until October 2021 were considered. Among the 247 identified articles, 19 studies were screened for eligibility and 11 met the criteria, with 4 studies including radiomics analyses. Results: We summarized the available literature based on a study of PET volumetric parameters and radiomics. Ten articles provided accurate details about volumetric parameters and their prospective value in tumour assessment. We included the data provided by these articles in a sub-analysis, but could not obtain statistically relevant results. Four publications analyzed the diagnostic potential of radiomics and the possibility of creating precise predictive models, their corresponding quality score being assessed. Conclusions: The use of PET volumetric parameters and radiomics analysis in patients with [18F]FDG-avid thyroid incidentalomas outlines a great prospect in diagnosis and stratification of patients with malignant nodules and may represent a way of limiting the need for unnecessary invasive procedures; however, further studies need to be performed for a standardization of the method.
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Affiliation(s)
- Mirela Gherghe
- Nuclear Medicine Department, University of Medicine and Pharmacy Carol Davila Bucharest, 050474 Bucharest, Romania; (M.G.); (M.-D.M.)
- Nuclear Medicine Department, Institute of Oncology “Profesor Doctor Alexandru Trestioreanu”, 022328 Bucharest, Romania
| | - Alexandra Maria Lazar
- Nuclear Medicine Department, Institute of Oncology “Profesor Doctor Alexandru Trestioreanu”, 022328 Bucharest, Romania
- Correspondence:
| | - Mario-Demian Mutuleanu
- Nuclear Medicine Department, University of Medicine and Pharmacy Carol Davila Bucharest, 050474 Bucharest, Romania; (M.G.); (M.-D.M.)
- Nuclear Medicine Department, Institute of Oncology “Profesor Doctor Alexandru Trestioreanu”, 022328 Bucharest, Romania
| | - Adina Elena Stanciu
- Carcinogenesis and Molecular Biology Department, Institute of Oncology “Profesor Doctor Alexandru Trestioreanu”, 022328 Bucharest, Romania;
| | - Sorina Martin
- Endocrinology Department, Elias Emergency University Clinic Hospital, 011461 Bucharest, Romania;
- Endocrinology Department, University of Medicine and Pharmacy Carol Davila Bucharest, 050474 Bucharest, Romania
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15
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de Koster EJ, Noortman WA, Mostert JM, Booij J, Brouwer CB, de Keizer B, de Klerk JMH, Oyen WJG, van Velden FHP, de Geus-Oei LF, Vriens D. Quantitative classification and radiomics of [ 18F]FDG-PET/CT in indeterminate thyroid nodules. Eur J Nucl Med Mol Imaging 2022; 49:2174-2188. [PMID: 35138444 PMCID: PMC9165273 DOI: 10.1007/s00259-022-05712-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 01/26/2022] [Indexed: 12/12/2022]
Abstract
PURPOSE To evaluate whether quantitative [18F]FDG-PET/CT assessment, including radiomic analysis of [18F]FDG-positive thyroid nodules, improved the preoperative differentiation of indeterminate thyroid nodules of non-Hürthle cell and Hürthle cell cytology. METHODS Prospectively included patients with a Bethesda III or IV thyroid nodule underwent [18F]FDG-PET/CT imaging. Receiver operating characteristic (ROC) curve analysis was performed for standardised uptake values (SUV) and SUV-ratios, including assessment of SUV cut-offs at which a malignant/borderline neoplasm was reliably ruled out (≥ 95% sensitivity). [18F]FDG-positive scans were included in radiomic analysis. After segmentation at 50% of SUVpeak, 107 radiomic features were extracted from [18F]FDG-PET and low-dose CT images. Elastic net regression classifiers were trained in a 20-times repeated random split. Dimensionality reduction was incorporated into the splits. Predictive performance of radiomics was presented as mean area under the ROC curve (AUC) across the test sets. RESULTS Of 123 included patients, 84 (68%) index nodules were visually [18F]FDG-positive. The malignant/borderline rate was 27% (33/123). SUV-metrices showed AUCs ranging from 0.705 (95% CI, 0.601-0.810) to 0.729 (0.633-0.824), 0.708 (0.580-0.835) to 0.757 (0.650-0.864), and 0.533 (0.320-0.747) to 0.700 (0.502-0.898) in all (n = 123), non-Hürthle (n = 94), and Hürthle cell (n = 29) nodules, respectively. At SUVmax, SUVpeak, SUVmax-ratio, and SUVpeak-ratio cut-offs of 2.1 g/mL, 1.6 g/mL, 1.2, and 0.9, respectively, sensitivity of [18F]FDG-PET/CT was 95.8% (95% CI, 78.9-99.9%) in non-Hürthle cell nodules. In Hürthle cell nodules, cut-offs of 5.2 g/mL, 4.7 g/mL, 3.4, and 2.8, respectively, resulted in 100% sensitivity (95% CI, 66.4-100%). Radiomic analysis of 84 (68%) [18F]FDG-positive nodules showed a mean test set AUC of 0.445 (95% CI, 0.290-0.600) for the PET model. CONCLUSION Quantitative [18F]FDG-PET/CT assessment ruled out malignancy in indeterminate thyroid nodules. Distinctive, higher SUV cut-offs should be applied in Hürthle cell nodules to optimize rule-out ability. Radiomic analysis did not contribute to the additional differentiation of [18F]FDG-positive nodules. TRIAL REGISTRATION NUMBER This trial is registered with ClinicalTrials.gov: NCT02208544 (5 August 2014), https://clinicaltrials.gov/ct2/show/NCT02208544 .
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Affiliation(s)
- Elizabeth J de Koster
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, the Netherlands.
| | - Wyanne A Noortman
- Department of Radiology, Section of Nuclear Medicine, Leiden University Medical Center, Leiden, the Netherlands
- Biomedical Photonic Imaging Group, University of Twente, Enschede, the Netherlands
| | - Jacob M Mostert
- Department of Radiology, Section of Nuclear Medicine, Leiden University Medical Center, Leiden, the Netherlands
- Delft University of Technology, Delft, the Netherlands
| | - Jan Booij
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, Location Academic Medical Center, Amsterdam, the Netherlands
| | | | - Bart de Keizer
- Department of Radiology and Nuclear Medicine, University Medical Centre Utrecht, Utrecht, the Netherlands
| | - John M H de Klerk
- Department of Nuclear Medicine, Meander Medical Centre, Amersfoort, the Netherlands
| | - Wim J G Oyen
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
- Department of Radiology and Nuclear Medicine, Rijnstate Hospital, Arnhem, the Netherlands
- Department of Biomedical Sciences and Humanitas Clinical and Research Centre, Department of Nuclear Medicine, Humanitas University, Milan, Italy
| | - Floris H P van Velden
- Department of Radiology, Section of Nuclear Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Lioe-Fee de Geus-Oei
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
- Department of Radiology, Section of Nuclear Medicine, Leiden University Medical Center, Leiden, the Netherlands
- Biomedical Photonic Imaging Group, University of Twente, Enschede, the Netherlands
| | - Dennis Vriens
- Department of Radiology, Section of Nuclear Medicine, Leiden University Medical Center, Leiden, the Netherlands
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16
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Dondi F, Pasinetti N, Gatta R, Albano D, Giubbini R, Bertagna F. Comparison between Two Different Scanners for the Evaluation of the Role of 18F-FDG PET/CT Semiquantitative Parameters and Radiomics Features in the Prediction of Final Diagnosis of Thyroid Incidentalomas. J Clin Med 2022; 11:jcm11030615. [PMID: 35160067 PMCID: PMC8836668 DOI: 10.3390/jcm11030615] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 01/19/2022] [Accepted: 01/25/2022] [Indexed: 12/24/2022] Open
Abstract
The aim of this study was to compare two different tomographs for the evaluation of the role of semiquantitative PET/CT parameters and radiomics features (RF) in the prediction of thyroid incidentalomas (TIs) at 18F-FDG imaging. A total of 221 patients with the presence of TIs were retrospectively included. After volumetric segmentation of each TI, semiquantitative parameters and RF were extracted. All of the features were tested for significant differences between the two PET scanners. The performances of all of the features in predicting the nature of TIs were analyzed by testing three classes of final logistic regression predictive models, one for each tomograph and one with both scanners together. Some RF resulted significantly different between the two scanners. PET/CT semiquantitative parameters were not able to predict the final diagnosis of TIs while GLCM-related RF (in particular GLCM entropy_log2 e GLCM entropy_log10) together with some GLRLM-related and GLZLM-related features presented the best predictive performances. In particular, GLCM entropy_log2, GLCM entropy_log10, GLZLM SZHGE, GLRLM HGRE and GLRLM HGZE resulted the RF with best performances. Our study enabled the selection of some RF able to predict the final nature of TIs discovered at 18F-FDG PET/CT imaging. Classic semiquantitative and volumetric PET/CT parameters did not reveal these abilities. Furthermore, a good overlap in the extraction of RF between the two scanners was underlined.
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Affiliation(s)
- Francesco Dondi
- Nuclear Medicine, Università degli Studi di Brescia and ASST Spedali Civili Brescia, 25123 Brescia, Italy; (F.D.); (R.G.); (F.B.)
| | - Nadia Pasinetti
- Radiation Oncology Department, ASST Valcamonica Esine and Università degli Studi di Brescia, 25040 Brescia, Italy;
| | - Roberto Gatta
- Dipartimento di Scienze Cliniche e Sperimentali dell’Università degli Studi di Brescia, 25123 Brescia, Italy;
| | - Domenico Albano
- Nuclear Medicine, Università degli Studi di Brescia and ASST Spedali Civili Brescia, 25123 Brescia, Italy; (F.D.); (R.G.); (F.B.)
- Correspondence:
| | - Raffaele Giubbini
- Nuclear Medicine, Università degli Studi di Brescia and ASST Spedali Civili Brescia, 25123 Brescia, Italy; (F.D.); (R.G.); (F.B.)
| | - Francesco Bertagna
- Nuclear Medicine, Università degli Studi di Brescia and ASST Spedali Civili Brescia, 25123 Brescia, Italy; (F.D.); (R.G.); (F.B.)
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17
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Lee H, Chung YS, Lee JH, Lee KY, Hwang KH. Characterization of focal hypermetabolic thyroid incidentaloma: An analysis with F-18 fluorodeoxyglucose positron emission tomography/computed tomography parameters. World J Clin Cases 2022; 10:155-165. [PMID: 35071515 PMCID: PMC8727242 DOI: 10.12998/wjcc.v10.i1.155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 10/09/2021] [Accepted: 11/25/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Incidentally found thyroid tumor (thyroid incidentaloma, TI) on F-18 fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET-CT) is reported in 2.5%-5% of patients being investigated for non-thyroid purposes. Up to 50% of these cases have been diagnosed to be malignant by cytological/histological results. Ultrasonography (US) and fine-needle aspiration cytology are recommended for thyroid nodules with high FDG uptake (hypermetabolism) that are 1 cm or greater in size. It is important to accurately determine whether a suspicious hypermetabolic TI is malignant or benign.
AIM To distinguish malignant hypermetabolic TIs from benign disease by analyzing F-18 FDG PET-CT parameters and to identify a cut-off value.
METHODS Totally, 12761 images of patients who underwent F-18 FDG PET-CT for non-thyroid purposes at our hospital between January 2016 and December 2020 were retrospectively reviewed, and 339 patients [185 men (mean age: 68 ± 11.2) and 154 women (mean age: 63 ± 15.0)] were found to have abnormal, either focal or diffuse, thyroid FDG uptake. After a thorough review of their medical records, US, and cytological/histological reports, 46 eligible patients with focal hypermetabolic TI were included in this study. The TIs were categorized as malignant and benign according to the cytological/histological reports, and four PET parameters [standardized uptake value (SUV)max, SUVpeak, SUVmean, and metabolic tumor volume (MTV)] were measured on FDG PET-CT. Total lesion glycolysis (TLG) was calculated by multiplying the SUVmean by MTV. Both parametric and non-parametric methods were used to compare the five parameters between malignant and benign lesions. Receiver operating characteristic (ROC) curve analysis was performed to identify a cut-off value.
RESULTS Each of the 46 patients [12 men (26.1%; mean age: 62 ± 13.1 years) and 34 women (73.9%; mean age: 60 ± 12.0 years)] with focal hypermetabolic TIs had one focal hypermetabolic TI. Among them, 26 (56.5%) were malignant and 20 (43.5%) were benign. SUVmax, SUVpeak, SUVmean, and TLG were all higher in malignant lesions than benign ones, but the difference was statistically significant (P = 0.012) only for SUVmax. There was a positive linear correlation (r = 0.339) between SUVmax and the diagnosis of malignancy. ROC curve analysis for SUVmax revealed an area under the curve of 0.702 (P < 0.05, 95% confidence interval: 0.550-0.855) and SUVmax cut-off of 8.5 with a sensitivity of 0.615 and a specificity of 0.789.
CONCLUSION More than half of focal hypermetabolic TIs on F-18 FDG PET-CT were revealed as malignant lesions, and SUVmax was the best parameter for discriminating between malignant and benign disease. Unexpected focal hypermetabolic TIs with the SUVmax above the cut-off value of 8.5 may have a greater than 70% chance of malignancy; therefore, further active assessment is required.
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Affiliation(s)
- Haejun Lee
- Department of Nuclear Medicine, Gachon University College of Medicine, Gil Medical Center, Incheon 21565, South Korea
| | - Yoo Seung Chung
- Department of Endocrine Surgery, Gachon University College of Medicine, Gil Medical Center, Incheon 21565, South Korea
| | - Joon-Hyop Lee
- Department of Endocrine Surgery, Gachon University College of Medicine, Gil Medical Center, Incheon 21565, South Korea
| | - Ki-Young Lee
- Department of Endocrinology and Metabolism, Gachon University College of Medicine, Gil Medical Center, Incheon 21565, South Korea
| | - Kyung-Hoon Hwang
- Department of Nuclear Medicine, Gachon University College of Medicine, Gil Medical Center, Incheon 21565, South Korea
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de Koster EJ, de Geus-Oei LF, Brouwers AH, van Dam EWCM, Dijkhorst-Oei LT, van Engen-van Grunsven ACH, van den Hout WB, Klooker TK, Netea-Maier RT, Snel M, Oyen WJG, Vriens D. [ 18F]FDG-PET/CT to prevent futile surgery in indeterminate thyroid nodules: a blinded, randomised controlled multicentre trial. Eur J Nucl Med Mol Imaging 2022; 49:1970-1984. [PMID: 34981165 PMCID: PMC9016050 DOI: 10.1007/s00259-021-05627-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 11/16/2021] [Indexed: 01/21/2023]
Abstract
Purpose To assess the impact of an [18F]FDG-PET/CT-driven diagnostic workup to rule out malignancy, avoid futile diagnostic surgeries, and improve patient outcomes in thyroid nodules with indeterminate cytology. Methods In this double-blinded, randomised controlled multicentre trial, 132 adult euthyroid patients with scheduled diagnostic surgery for a Bethesda III or IV thyroid nodule underwent [18F]FDG-PET/CT and were randomised to an [18F]FDG-PET/CT-driven or diagnostic surgery group. In the [18F]FDG-PET/CT-driven group, management was based on the [18F]FDG-PET/CT result: when the index nodule was visually [18F]FDG-positive, diagnostic surgery was advised; when [18F]FDG-negative, active surveillance was recommended. The nodule was presumed benign when it remained unchanged on ultrasound surveillance. In the diagnostic surgery group, all patients were advised to proceed to the scheduled surgery, according to current guidelines. The primary outcome was the fraction of unbeneficial patient management in one year, i.e., diagnostic surgery for benign nodules and active surveillance for malignant/borderline nodules. Intention-to-treat analysis was performed. Subgroup analyses were performed for non-Hürthle cell and Hürthle cell nodules. Results Patient management was unbeneficial in 42% (38/91 [95% confidence interval [CI], 32–53%]) of patients in the [18F]FDG-PET/CT-driven group, as compared to 83% (34/41 [95% CI, 68–93%]) in the diagnostic surgery group (p < 0.001). [18F]FDG-PET/CT-driven management avoided 40% (25/63 [95% CI, 28–53%]) diagnostic surgeries for benign nodules: 48% (23/48 [95% CI, 33–63%]) in non-Hürthle cell and 13% (2/15 [95% CI, 2–40%]) in Hürthle cell nodules (p = 0.02). No malignant or borderline tumours were observed in patients under surveillance. Sensitivity, specificity, negative and positive predictive value, and benign call rate (95% CI) of [18F]FDG-PET/CT were 94.1% (80.3–99.3%), 39.8% (30.0–50.2%), 95.1% (83.5–99.4%), 35.2% (25.4–45.9%), and 31.1% (23.3–39.7%), respectively. Conclusion An [18F]FDG-PET/CT-driven diagnostic workup of indeterminate thyroid nodules leads to practice changing management, accurately and oncologically safely reducing futile surgeries by 40%. For optimal therapeutic yield, application should be limited to non-Hürthle cell nodules. Trial registration number This trial is registered with ClinicalTrials.gov: NCT02208544 (5 August 2014), https://clinicaltrials.gov/ct2/show/NCT02208544. Supplementary Information The online version contains supplementary material available at 10.1007/s00259-021-05627-2.
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Affiliation(s)
- Elizabeth J de Koster
- Department of Radiology and Nuclear Medicine, Radboud University Medical Centre, Nijmegen, the Netherlands.
| | - Lioe-Fee de Geus-Oei
- Department of Radiology and Nuclear Medicine, Radboud University Medical Centre, Nijmegen, the Netherlands
- Department of Radiology, Section of Nuclear Medicine, Leiden University Medical Center, Leiden, the Netherlands
- Biomedical Photonic Imaging Group, University of Twente, Enschede, the Netherlands
| | - Adrienne H Brouwers
- Department of Nuclear Medicine and Molecular Imaging Groningen, University of Groningen, University Medical Centre Groningen, Groningen, the Netherlands
| | - Eveline W C M van Dam
- Department of Internal Medicine, Division of Endocrinology, Amsterdam University Medical Centers, Location VU Medical Center, Amsterdam, the Netherlands
| | | | | | - Wilbert B van den Hout
- Department of Medical Decision Making, Leiden University Medical Center, Leiden, the Netherlands
| | - Tamira K Klooker
- Department of Endocrinology and Metabolism, Amsterdam Gastroenterology Endocrinology and Metabolism, Amsterdam University Medical Centers, Location Academic Medical Center, Amsterdam, the Netherlands
- Department of Internal Medicine, Flevo Hospital, Almere, the Netherlands
| | - Romana T Netea-Maier
- Department of Internal Medicine, Division of Endocrinology, Radboud University Medical Centre, Nijmegen, the Netherlands
| | - Marieke Snel
- Department of Medicine, Division of Endocrinology, Leiden University Medical Center, Leiden, the Netherlands
| | - Wim J G Oyen
- Department of Radiology and Nuclear Medicine, Radboud University Medical Centre, Nijmegen, the Netherlands
- Department of Radiology and Nuclear Medicine, Rijnstate Hospital, Arnhem, the Netherlands
- Department of Biomedical Sciences and Humanitas Clinical and Research Centre, Department of Nuclear Medicine, Humanitas University, Milan, Italy
| | - Dennis Vriens
- Department of Radiology, Section of Nuclear Medicine, Leiden University Medical Center, Leiden, the Netherlands
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19
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Giovanella L, Milan L, Piccardo A, Bottoni G, Cuzzocrea M, Paone G, Ceriani L. Radiomics analysis improves 18FDG PET/CT-based risk stratification of cytologically indeterminate thyroid nodules. Endocrine 2022; 75:202-210. [PMID: 34468949 PMCID: PMC8763930 DOI: 10.1007/s12020-021-02856-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 08/21/2021] [Indexed: 01/13/2023]
Abstract
PURPOSE As ~25% of cytologically indeterminate thyroid nodules harbour malignancy, diagnostic lobectomy is still performed in many cases. 18FDG PET/CT rules out malignancy in visually negative nodules; however, none of the currently available interpretation criteria differentiates malignant from benign 18FDG-avid nodules. We evaluated the ability of PET metrics and radiomics features (RFs) to predict final diagnosis of 18FDG-avid cytologically indeterminate thyroid nodules. METHODS Seventy-eight patients were retrospectively included. After volumetric segmentation of each thyroid lesion, 4 PET metrics and 107 RFs were extracted. A logistic regression was performed including thyroid stimulating hormone, PET metrics, and RFs to assess their predictive performance. A linear combination of the resulting parameters generated a radiomics score (RS) that was matched with cytology classes (Bethesda III and IV) and compared with final diagnosis. RESULTS Two RFs (shape_Sphericity and glcm_Autocorrelation) differentiated malignant from benign lesions. A predictive model integrating RS and cytology classes effectively stratified the risk of malignancy. The prevalence of thyroid cancer increased from 5 to 37% and 79% in accordance with the number (score 0, 1 or 2, respectively) of positive biomarkers. CONCLUSIONS Our multiparametric model may be useful for reducing the number of diagnostic lobectomies with advantages in terms of costs and quality of life for patients.
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Affiliation(s)
- Luca Giovanella
- Clinic for Nuclear Medicine and Molecular Imaging, Imaging Institute of Southern Switzerland, Ente Ospedaliero Cantonale, 6500, Bellinzona, Switzerland.
- Clinic for Nuclear Medicine, University Hospital and University of Zurich, Zurich, Switzerland.
| | - Lisa Milan
- Clinic for Nuclear Medicine and Molecular Imaging, Imaging Institute of Southern Switzerland, Ente Ospedaliero Cantonale, 6500, Bellinzona, Switzerland
| | - Arnoldo Piccardo
- Department of Nuclear Medicine, E.O. "Ospedali Galliera", Genoa, Italy
| | - Gianluca Bottoni
- Department of Nuclear Medicine, E.O. "Ospedali Galliera", Genoa, Italy
| | - Marco Cuzzocrea
- Clinic for Nuclear Medicine and Molecular Imaging, Imaging Institute of Southern Switzerland, Ente Ospedaliero Cantonale, 6500, Bellinzona, Switzerland
| | - Gaetano Paone
- Clinic for Nuclear Medicine and Molecular Imaging, Imaging Institute of Southern Switzerland, Ente Ospedaliero Cantonale, 6500, Bellinzona, Switzerland
| | - Luca Ceriani
- Clinic for Nuclear Medicine and Molecular Imaging, Imaging Institute of Southern Switzerland, Ente Ospedaliero Cantonale, 6500, Bellinzona, Switzerland
- Faculty of Biomedical Sciences, Università della Svizzera Italiana (USI), Lugano, Switzerland
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Şahin Ö, Kaya B, Aydın Z, Şen AE, İyisoy MS, Aydın A. Prostate incidentaloma on 18F-fluorodeoxyglucose positron emission tomography: Diagnostic value of volumetric positron emission tomography parameters. Nuklearmedizin 2021; 60:394-402. [PMID: 34243190 DOI: 10.1055/a-1525-7607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE To evaluate whether volumetric PET parameters such as metabolic tumor volume (MTV) and total lesion glycolysis (TLG) contributed to maximum standardized uptake value (SUVmax) in predicting prostate carcinoma in the prostate incidentalomas (PI) in 18F-FDG PET/CT. MATERIALS AND METHODS This retrospective study comprised 107 patients with PI of 4723 male patients who had undergone 18F-FDG PET/CT. SUVmax and volumetric PET parameters of PIs were assessed. MTV and TLG were acquired with each SUV threshold as 2.5, 3.0, 3.5, 4.0, 4.5, and 5.0. RESULTS The PI incidence was 2.3%, and the malignancy ratio of PI was 15.9%. According to further analysis results, 17 patients were in the malignant group, and 46 patients were in the benign group. Malignant PIs had higher SUVmax (10.6 vs. 6.4 and p<0.01), MTV (all p < 0.01) and TLG (all p < 0.01) than benign incidentalomas. All volumetric PET parameters had higher area under the curve (AUC) than SUVmax. SUVmax AUC was 0.835 [95% confidence interval (CI): 0.728-0.942]. MTV 2.5 and TLG 2.5 had the highest performance for predicting malignant PI.MTV2.5 AUC was 0.871 (95% CI: 0.775-0.968), and TLG2.5 AUC was 0.882 (95% CI: 0.797-0.967). Using TLG 2.5 greater than 29.8 as the cut-off point, the sensitivity and specificity for malignancy prediction were 94.1% and 82.6%, respectively. CONCLUSION In this study, in which the effectiveness of volumetric parameters in the diagnosis of PI was evaluated for the first time, it was shown that they could potentially have clinical value along with SUVmax.
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Affiliation(s)
- Özlem Şahin
- Department of Nuclear Medicine, Necmettin Erbakan University Meram Medical Faculty Hospital, Konya, Turkey
| | - Buğra Kaya
- Department of Nuclear Medicine, Necmettin Erbakan University Meram Medical Faculty Hospital, Konya, Turkey
| | - Zeynep Aydın
- Department of Nuclear Medicine, Necmettin Erbakan University Meram Medical Faculty Hospital, Konya, Turkey
| | - Ahmet Eren Şen
- Department of Nuclear Medicine, Necmettin Erbakan University Meram Medical Faculty Hospital, Konya, Turkey
| | - Mehmet Sinan İyisoy
- Department of Medical Education and Informatics, Necmettin Erbakan University Meram Medical Faculty Hospital, Konya, Turkey
| | - Arif Aydın
- Department of Urology, Necmettin Erbakan University Meram Medical Faculty Hospital, Konya, Turkey
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Giovanella L, Avram A, Clerc J. Molecular Imaging for Thyrotoxicosis and Thyroid Nodules. J Nucl Med 2021; 62:20S-25S. [PMID: 34230069 DOI: 10.2967/jnumed.120.246017] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 09/21/2020] [Indexed: 12/14/2022] Open
Abstract
After exclusion of exogenous iodine overload, radioiodine uptake (RAIU) testing with 123I or 131I enables the accurate evaluation and quantification of iodine uptake and kinetics within thyroid cells. In addition, scintigraphic evaluation with 123I or 99mTc-pertechnetate (99mTc04-) provides the topographic distribution of thyroid cell activity and allows the detection and localization of ectopic thyroid tissue. Destructive thyrotoxicosis is characterized by abolished or reduced uptake whereas productive thyrotoxicosis (i.e., hyperthyroidism "sensu strictu") is characterized by high RAIU with scintigraphically diffuse (i.e., Graves disease and diffuse thyroid autonomy) or focal (i.e., autonomously functioning thyroid nodules [AFTN]) overactivity. Accordingly, RAIU or thyroid scintigraphy are widely used to differentiate different causes of thyrotoxicosis. In addition, several radiopharmaceuticals are also available to help in differentiating benign from malignant thyroid nodules and inform clinical decision making. In fact, AFTNs can be safely excluded from fine-needle aspiration biopsy while either 99mTc-methoxyisobutylisonitrile (MIBI) and 18F-FDG may complement the work-up of cytologically indeterminate cold nodules and contribute to reducing the need for diagnostic lobectomies/thyroidectomies. Finally, RAIU studies are also useful for calculating the administered therapeutic activity of 131I to treat hyperthyroidism and euthyroid multinodular goiter. All considered, thyroid molecular imaging allows us to characterize molecular/functional aspects of different thyroid diseases, even before clinical symptoms become manifest and remains integral to properly managing such conditions. Our present paper summarizes basic concepts, clinical applications, and potential developments of thyroid molecular imaging in patients affected by thyrotoxicosis and thyroid nodules.
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Affiliation(s)
- Luca Giovanella
- Clinic for Nuclear Medicine and Competence Center for Thyroid Diseases, Imaging Institute of Southern Switzerland, Bellinzona, Switzerland;
- Clinic for Nuclear Medicine, University Hospital and University of Zurich, Zurich, Switzerland
| | - Anca Avram
- Division of Nuclear Medicine, Department of Radiology, University of Michigan, Ann Arbor, Michigan; and
| | - Jerome Clerc
- Department of Nuclear Medicine, Cochin Hospital, Assistance Publique Hôpitaux de Paris, DMU Imagina, University of Paris, Paris, France
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A Systematic Review of PET Textural Analysis and Radiomics in Cancer. Diagnostics (Basel) 2021; 11:diagnostics11020380. [PMID: 33672285 PMCID: PMC7926413 DOI: 10.3390/diagnostics11020380] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 02/10/2021] [Accepted: 02/19/2021] [Indexed: 12/12/2022] Open
Abstract
Background: Although many works have supported the utility of PET radiomics, several authors have raised concerns over the robustness and replicability of the results. This study aimed to perform a systematic review on the topic of PET radiomics and the used methodologies. Methods: PubMed was searched up to 15 October 2020. Original research articles based on human data specifying at least one tumor type and PET image were included, excluding those that apply only first-order statistics and those including fewer than 20 patients. Each publication, cancer type, objective and several methodological parameters (number of patients and features, validation approach, among other things) were extracted. Results: A total of 290 studies were included. Lung (28%) and head and neck (24%) were the most studied cancers. The most common objective was prognosis/treatment response (46%), followed by diagnosis/staging (21%), tumor characterization (18%) and technical evaluations (15%). The average number of patients included was 114 (median = 71; range 20–1419), and the average number of high-order features calculated per study was 31 (median = 26, range 1–286). Conclusions: PET radiomics is a promising field, but the number of patients in most publications is insufficient, and very few papers perform in-depth validations. The role of standardization initiatives will be crucial in the upcoming years.
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Hirata K, Tamaki N. Quantitative FDG PET Assessment for Oncology Therapy. Cancers (Basel) 2021; 13:cancers13040869. [PMID: 33669531 PMCID: PMC7922629 DOI: 10.3390/cancers13040869] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 02/15/2021] [Accepted: 02/16/2021] [Indexed: 12/12/2022] Open
Abstract
Simple Summary PET enables quantitative assessment of tumour biology in vivo. Accumulation of F-18 fluorodeoxyglucose (FDG) may reflect tumour metabolic activity. Quantitative assessment of FDG uptake can be applied for treatment monitoring. Numerous studies indicated biochemical change assessed by FDG-PET as a more sensitive marker than morphological change. Those with complete metabolic response after therapy may show better prognosis. Assessment of metabolic change may be performed using absolute FDG uptake or metabolic tumour volume. More recently, radiomics approaches have been applied to FDG PET. Texture analysis quantifies intratumoral heterogeneity in a voxel-by-voxel basis. Combined with various machine learning techniques, these new quantitative parameters hold a promise for assessing tissue characterization and predicting treatment effect, and could also be used for future prognosis of various tumours. Abstract Positron emission tomography (PET) has unique characteristics for quantitative assessment of tumour biology in vivo. Accumulation of F-18 fluorodeoxyglucose (FDG) may reflect tumour characteristics based on its metabolic activity. Quantitative assessment of FDG uptake can often be applied for treatment monitoring after chemotherapy or chemoradiotherapy. Numerous studies indicated biochemical change assessed by FDG PET as a more sensitive marker than morphological change estimated by CT or MRI. In addition, those with complete metabolic response after therapy may show better disease-free survival and overall survival than those with other responses. Assessment of metabolic change may be performed using absolute FDG uptake in the tumour (standardized uptake value: SUV). In addition, volumetric parameters such as metabolic tumour volume (MTV) have been introduced for quantitative assessment of FDG uptake in tumour. More recently, radiomics approaches that focus on image-based precision medicine have been applied to FDG PET, as well as other radiological imaging. Among these, texture analysis extracts intratumoral heterogeneity on a voxel-by-voxel basis. Combined with various machine learning techniques, these new quantitative parameters hold a promise for assessing tissue characterization and predicting treatment effect, and could also be used for future prognosis of various tumours, although multicentre clinical trials are needed before application in clinical settings.
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Affiliation(s)
- Kenji Hirata
- Department of Diagnostic Imaging, Graduate School of Medicine, Hokkaido University, Sapporo 060-8638, Japan;
| | - Nagara Tamaki
- Department of Radiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
- Correspondence:
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