Automated threshold selection on whole-body 18F-FDG PET/CT for assessing tumor metabolic response

Abstract Introduction [18F]-FDG-PET/CT positive metastatic lesions in radioiodine-refractory differentiated thyroid cancer (RAI-R DTC) have a poor prognosis and lenvatinib represents the best therapy. We investigated the role of [ 18F]-FDG-PET/CT in the evaluation of metabolic response and prediction of the outcome of RAI-R DTC patients treated with lenvatinib. Materials and Methods Thirty-three progressive metastatic RAI-R DTC patients treated with lenvatinib were investigated at baseline and during follow-up with biochemical (Tg/TgAb), morphological (whole-body CT scan) and metabolic evaluation ([ 18F]-FDG-PET/CT). Results Nineteen of thirty-three (57.6%) patients showed the greatest metabolic response at the first [ 18F]-FDG-PET/CT scan, performed after 4 weeks of lenvatinib, while 5/33 (15.1%) patients had this response later. Moreover, 66.7% of patients had both a metabolic response at the first [ 18F]-FDG-PET/CT scan and a morphological response at the first CT scan. We observed a correlation between the metabolic response at [ 18F]-FDG-PET/CT scan performed after 4 weeks of treatment and the biochemical response at the same time in 60.6% of patients. The median overall survival (OS) was significantly longer in patients with either a metabolic response at last [ 18F]-FDG-PET/CT (40.00 vs 8.98 months) or a morphological response at last CT scan (37.22 vs 9.53 months) than in those without response. Moreover, the OS was longer in patients with a metabolic response at [ 18F]-FDG-PET/CT performed after 4 weeks of treatment (36.53 vs 11.28 months). Conclusions Our data show that [ 18F]-FDG-PET/CT can early predict the response to lenvatinib and correlates with the OS of RAI-R DTC patients treated with this drug.

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Diagnostic Performance of 18F-FDG PET/CT Semiquantitative Analysis in the Management of Sarcoidosis

Current Medical Imaging Formerly Current Medical Imaging Reviews ◽

10.2174/1573405614666180522075828 ◽

2018 ◽

Vol 15 (1) ◽

pp. 32-38 ◽

Cited By ~ 1

Author(s):

Giuseppe Rubini ◽

Cristina Ferrari ◽

Corinna Altini ◽

Alessandra Cimino ◽

Margherita Fanelli ◽

...

Keyword(s):

Fdg Pet ◽

Metabolic Response ◽

Statistical Significance ◽

Clinical Stage ◽

Whole Body ◽

Mean Values ◽

Pet Ct ◽

Response Groups ◽

18F Fdg ◽

Fdg Pet Ct

Background: Sarcoidosis is a multisystem granulomatous disorder of unknown origin characterized by nonspecific clinical symptomatology. 18F-FDG PET/CT can visualize activated inflammatory cells of sarcoidosis and simultaneously provide whole-body images. </P><P> Objective: To evaluate the clinical usefulness of 18F-FDG PET/CT and its semiquantitative parameters for the assessment of treatment efficacy in patients with sarcoidosis. Methods: Thirty-one consecutive patients who performed 18F-FDG PET/CT for sarcoidosis assessment were selected. All subjects performed 18F-FDG PET/CT before any treatment (PET1) and after 6-12 months (PET2). SUVmax and SUVmean on PET1 and PET2 were collected. SUVs values were employed to evaluate the ratios with the liver (R-LIVERmax, R-LIVERmean) and the blood (R-BLOODmax, R-BLOODmean). The difference between the PET1 and PET2 values was evaluated (ΔSUVmax, ΔSUVmean, ΔR-LIVERmax, ΔR-LIVERmean, ΔR-BLOODmax, ΔR-BLOODmean). Patients were classified as Responders (R), Partial-Responders (PR) and Non- Responders (NR). Results: Seventeen patients (54.8%) had a complete metabolic response (R), 4 (12.9%) were PR while 10 (32.3%) had no Metabolic Response (NR). The chi-square test showed that response groups were related neither to the stage of disease (p=0.59) nor to therapy performed (p<0.079). The comparison between each Δ semiquantitative parameter showed a statistically significant decrease from PET1 to PET2 (0.0001 < p < 0.002). The comparison between Δ mean values in relation to response groups showed to be statistically significant (0.001 < p < 0.005). Conversely, they did not show statistical significance in relation to the clinical stage groups and to the kind of therapy performed (p>0.05). Pearson’s coefficient demonstrated a reverse correlation between a number of sites still involved in disease after therapy and each Δ semiquantitative parameters (p≤0.0001). Conclusion: 18F-FDG PET/CT should be considered a useful technique for the evaluation of sarcoidosis and semiquantitative parameters. Further studies are needed to determine the long-term impact of 18F-FDG PET/CT on clinical outcomes.

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Low positive yield from routine inclusion of the brain in whole-body 18F-FDG PET/CT imaging for noncerebral malignancies

Nuclear Medicine Communications ◽

10.1097/mnm.0b013e32836066c0 ◽

2013 ◽

Vol 34 (6) ◽

pp. 540-543 ◽

Cited By ~ 8

Author(s):

Kuruva Manohar ◽

Anish Bhattacharya ◽

Bhagwant R. Mittal

Keyword(s):

Fdg Pet ◽

Ct Imaging ◽

Whole Body ◽

Pet Ct ◽

18F Fdg ◽

Fdg Pet Ct ◽

The Brain

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Comparison of the diagnostic performance and impact on management of 18F-FDG PET/CT and whole-body MRI in multiple myeloma

European Journal of Nuclear Medicine and Molecular Imaging ◽

10.1007/s00259-020-05182-2 ◽

2021 ◽

Author(s):

Olwen Westerland ◽

◽

Ashik Amlani ◽

Christian Kelly-Morland ◽

Michal Fraczek ◽

...

Keyword(s):

Multiple Myeloma ◽

Clinical Data ◽

Bone Disease ◽

Fdg Pet ◽

Diagnostic Performance ◽

Whole Body ◽

Bone Lesions ◽

Pet Ct ◽

18F Fdg ◽

Fdg Pet Ct

Abstract Purpose Comparative data on the impact of imaging on management is lacking for multiple myeloma. This study compared the diagnostic performance and impact on management of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) and whole-body magnetic resonance imaging (WBMRI) in treatment-naive myeloma. Methods Forty-six patients undergoing 18F-FDG PET/CT and WBMRI were reviewed by a nuclear medicine physician and radiologist, respectively, for the presence of myeloma bone disease. Blinded clinical and imaging data were reviewed by two haematologists in consensus and management recorded following clinical data ± 18F-FDG PET/CT or WBMRI. Bone disease was defined using International Myeloma Working Group (IMWG) criteria and a clinical reference standard. Per-patient sensitivity for lesion detection was established. McNemar test compared management based on clinical assessment ± 18F-FDG PET/CT or WBMRI. Results Sensitivity for bone lesions was 69.6% (32/46) for 18F-FDG PET/CT (54.3% (25/46) for PET component alone) and 91.3% (42/46) for WBMRI. 27/46 (58.7%) of cases were concordant. In 19/46 patients (41.3%) WBMRI detected more focal bone lesions than 18F-FDG PET/CT. Based on clinical data alone, 32/46 (69.6%) patients would have been treated. Addition of 18F-FDG PET/CT to clinical data increased this to 40/46 (87.0%) patients (p = 0.02); and WBMRI to clinical data to 43/46 (93.5%) patients (p = 0.002). The difference in treatment decisions was not statistically significant between 18F-FDG PET/CT and WBMRI (p = 0.08). Conclusion Compared to 18F-FDG PET/CT, WBMRI had a higher per patient sensitivity for bone disease. However, treatment decisions were not statistically different and either modality would be appropriate in initial staging, depending on local availability and expertise.

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POSITRON EMISSION TOMOGRAPHY WITH 18F -FDG IN THE DIAGNOSIS OF PROSTHETIC HEART VALVE ENDOCARDITIS

Emergency Cardiology and Cardiovascular Risks ◽

10.51922/2616-633x.2021.5.2.1151 ◽

2021 ◽

Vol 5 (1) ◽

pp. 1151-1160

Author(s):

A.S. Lukashevich ◽

Keyword(s):

Computed Tomography ◽

Positron Emission Tomography ◽

Fdg Pet ◽

Prosthetic Heart Valve ◽

Emission Tomography ◽

Whole Body ◽

Positron Emission ◽

Pet Ct ◽

18F Fdg ◽

Fdg Pet Ct

Purpose. The purpose of the article is to evaluate the diagnostic significance of positron emission tomography / computed tomography with 18F -fluorodeoxyglucose (18F -FDG PET/CT) for the diagnosis of prosthetic endocarditis. Methods of research. The study included 82 patients with suspected prosthetic endocarditis in accordance with the criteria proposed by Duke University [1-5]. The patients received hospital treatment at the State Institution RSPC "Cardiology" from January 2016 to March 2021. The study was of a prospective, non-randomized, single-center cohort design. The duration of the monitor period was 12 months from the moment of patients’ inclusion in the study. Whole-body positron emission tomography / computed tomography (PET/CT) examinations were performed in 82 patients. 27 patients were selected for surgical treatment. Conservative treatment group included 16 patients. 27 patients were selected into the observation group, they were suspected to have prosthetic heart valve infection in the primary referral and underwent PET/CT scanning, according to which the diagnosis of prosthetic endocarditis was excluded. The event under the study did not develop in this group during the year of observation. Results and conclusion. The history of infective endocarditis was not statistically significant and did not increase the risk of developing prosthetic endocarditis in the sample presented. The Duke criteria are less reliable in establishing the diagnosis of prosthetic endocarditis. The median number of days from the date of the first prosthesis implantation to the onset of prosthetic endocarditis was about 4 years. This study revealed that the development of the infectious process in the area of the prosthesis was noted in a more distant postoperative period compared to literature data. Histological confirmation of infection was noted in 100% (27 patients) of cases in reoperated patients. The presence of a more formidable complication such as valve ring abscess located mainly in the projection of the aortic valve ring was quite common in both groups. Presepsin and Interleukin-6 have a statistically significant (U = 394,50 p = 0,01 and U = 94,50 p = 0.004) value in the prognosis of prosthetic endocarditis. Considering the data obtained from ROC analysis, it can be said that the cut-off point at which it is possible to diagnose prosthetic endocarditis based on PETCT is 2.85. The presented methods for the interpretation of whole-body FDG-PET/CT images of patients with suspected infectious complications after cardiac surgery, as well as with the presence of prosthetic endocarditis, show high sensitivity and specificity.

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Leydig cell tumor of the testis: an incidental finding at 18F-FDG PET/CT imaging

Egyptian Journal of Radiology and Nuclear Medicine ◽

10.1186/s43055-021-00646-3 ◽

2021 ◽

Vol 52 (1) ◽

Author(s):

Almalki Yassir

Keyword(s):

Leydig Cell ◽

Fdg Pet ◽

Chronic Rejection ◽

Ct Imaging ◽

The Body ◽

Whole Body ◽

Pet Ct ◽

18F Fdg ◽

The Right ◽

Fdg Pet Ct

Abstract Background Leydig cell tumors (LCTs) represent the most common form of stromal tumors. We reported the 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) findings of a patient with testicular LCT. Case presentation A 50-year-old man with a history of end-stage renal disease and renal transplantation 19 years ago. One year earlier, he started to have a chronic rejection. During the investigation to determine the cause of chronic rejection, a suspicious lesion in the graft with a collection around it was seen on ultrasound (US) images, raising the possibility of post-transplant lymphoproliferative disorder (PTLD). The patient was referred for further evaluation by whole body 18F-FDG PET/CT imaging. The image finding revealed an incidental hypermetabolic focal lesion in the right testicle—no other specific findings in the remaining parts of the body nor definitive FDG avid lymphadenopathy to suggest PTLD. Testicular US was requested and showed a well-defined right-sided heterogeneous hypoechoic intratesticular focal mass at the upper pole of the right testis with significant internal vascularity on the color Doppler imaging. The patient underwent a right radical orchidectomy, and the tumor was pathologically confirmed as an LCT. Conclusion In our case, 18F-FDG-PET/CT has been helpful in incidentally detecting this rare testicular tumor in a patient with suspected PTLD.

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