The ultrasound risk stratification systems for thyroid nodule have been evaluated against papillary carcinoma: a meta-analysis

Thyroid imaging reporting and data systems (TIRADS) are used to stratify the malignancy risk of thyroid nodule by ultrasound (US) examination. We conducted a meta-analysis to evaluate the pooled cancer prevalence and the relative prevalence of papillary, medullary, follicular thyroid cancer (PTC, MTC, and FTC) and other malignancies among nodules included in studies evaluating their performance. Four databases were searched until February 2020. Original articles with at least 1000 nodules, evaluating the performance of at least one TIRADS among AACE/ACE/AME, ACR-TIRADS, ATA, EU-TIRADS, or K-TIRADS, and reporting data on the histological diagnosis of malignant lesions were included. The number of malignant nodules, PTC, FTC, MTC and other malignancies in each study was extracted. For statistical pooling of data, a random-effects model was used. Nine studies were included, evaluating 19,494 thyroid nodules. The overall prevalence of malignancy was 34% (95%CI 21 to 49). Among 6162 histologically proven malignancies, the prevalence of PTC, FTC, MTC and other malignancies was 95%, 2%, 1%, and 1%, respectively. A high heterogeneity was found for all the outcomes. A limited number of studies generally conducted using a retrospective design was found, with possible selection bias. Acknowledging this limitation, TIRADSs should be regarded as accurate tools to diagnose PTC only. Proposed patterns and/or cut-offs should be revised and other strategies considered to improve their performance in the assessment of FTC, MTC and other malignancies

124I-MIBG: a new promising positron-emitting radiopharmaceutical for the evaluation of neuroblastoma

Neuroblastoma is the most common extra-cranial solid tumor in pediatric patients. Despite the established role of 123I-MIBG and 131I-MIBG scintigraphy in this tumor, only limited data are available regarding the use of 124I-metaiodobenzylguanidine (MIBG) positron emission tomography (PET)/computed tomography (CT). We present our preliminary experience with 124I-MIBG PET/CT: two pediatric patients affected by neuroblastoma, who underwent 124I-MIBG PET/CT for pre-therapy distribution evaluation and restaging purposes. We aimed to evaluate whether 124I-MIBG PET/CT can detect as many or more neuroblastoma lesions than 123I/131I-MIBG imaging. Our cases show promising results, although further validation and standardization of 124I-MIBG PET/CT are required

Metabolic and densitometric correlation between atherosclerotic plaque and trabecular bone: an 18F-Natrium-Fluoride PET/CT study

Increasing evidence links atherosclerosis to a decreased bone thickness. This correlation could reflect a bone/plaque interaction. Hereby we analyzed Hounsfield density (HU) and mineral turnover in bone and in the arterial calcifications (AC), using a computational method applied to PET/CT data. 79 18F-NaF PET/CT from patients with AC were retrospectively analyzed. Mean AC density and background-corrected uptake (TBR) were estimated after semi-automatic isocontour segmentation. The same values were assessed in the trabecular bone, using an automatic adaptive thresholding method. Patients were then stratified into terciles, according to their mean HU plaque density ("light", "medium" or "heavy" calcifications"). 35 18F-NaF PET/CT from patients without AC served as controls. Vertebral density and TBR were lower in patients than in controls (137\ub125 vs. 160\ub114 HU, P<0.001); (6.2\ub13.9 vs. 8.4\ub13.4, P<0.05). Mean trabecular TBR values were 8.3\ub14, 4.5\ub12.1 and 3.5\ub11.8 in light, medium and heavy AC groups, respectively (P<0.05 for light vs. medium and P<0.01 for light vs. heavy). Similarly, mean trabecular HU was 143\ub119, 127\ub126 and 119\ub118 in the three groups, respectively (P<0.01 for light vs. heavy). Mean AC density was inversely associated with the trabecular HU (R=-0.56, P<0.01). Conversely, plaques' TBR directly correlated with the one in trabecular bone (R=0.63, P<0.001). At multivariate analysis, the sole predictor of vertebral density was plaque HU (P<0.05). Our data highlight a correlation between plaque and bone morpho-functional parameters and suggest that observing skeletal bone characteristics could represent a novel window on atherosclerosis pathophysiology

124I-MIBG: a new promising positron-emitting radiopharmaceutical for the evaluation of neuroblastoma.

Neuroblastoma is the most common extra-cranial solid tumor in pediatric patients. Despite the established role of 123I-MIBG and 131I-MIBG scintigraphy in this tumor, only limited data are available regarding the use of 124I-metaiodobenzylguanidine (MIBG) positron emission tomography (PET)/computed tomography (CT). We present our preliminary experience with 124I-MIBG PET/CT: two pediatric patients affected by neuroblastoma, who underwent 124I-MIBG PET/CT for pre-therapy distribution evaluation and restaging purposes. We aimed to evaluate whether 124I-MIBG PET/CT can detect as many or more neuroblastoma lesions than 123I/131I-MIBG imaging. Our cases show promising results, although further validation and standardization of 124I-MIBG PET/CT are required

Patient Age Is an Independent Risk Factor of Relapse of Differentiated Thyroid Carcinoma and Improves the Performance of the American Thyroid Association Stratification System

Background: The 2015 American Thyroid Association (ATA) guidelines proposed a three-category system for estimating the risk of recurrence of differentiated thyroid carcinoma (DTC). This system includes several perioperative features, but not age at diagnosis. However, age has traditionally been recognized as a critical factor in the survival of DTC patients, and the eighth edition of TNM stated that patients older than 55 years were at higher risk of death. In this study, we raised the question of whether age at DTC diagnosis impacts on its risk of recurrence. Specifically, the present study aimed to (i) evaluate the association between age at diagnosis and structural recurrence and (ii) investigate whether age at diagnosis could improve the performance of the ATA system. Methods: During the study period, four institutions selected DTC patients treated with both thyroidectomy and radioiodine and who had follow-up for at least one year. Patients with proven structural evidence of disease during follow-up were identified, and disease-free survival (DFS) was calculated accordingly. Results: The study involved 1603 DTC patients with a median age of 49 years and DFS of 44 months. Disease recurred in 8%. The shortest DFS was found in the oldest patients. The Kaplan-Meier curves were calculated for each decade of age, and there was a significant association with DFS (p = 0.0014). Patients older than 55 years had significantly higher risk (hazard ratio [HR] 1.78, 95% confidence interval [CI 1.23-2.56]). The Kaplan-Meier curves of DFS in high-, intermediate-and low-risk groups showed a significant association only in the high-risk group (p = 0.0058). Patients older than 55 years had significantly higher risk of relapse over time only in the high-risk group (HR 2.15 [CI 2.01-4.53]). Cox's proportional analysis showed that the age cutoff of 55 years and the ATA system were significant predictors of relapse. Adding age at diagnosis above 55 years to the ATA system identified a subgroup of patients at highest risk for relapse. Conclusions: The age threshold adopted in the eighth edition of TNM staging system for DTC patients' prognosis also identifies cases at higher risk of relapse. Applying age at diagnosis, with a cutoff of 55 years, to the ATA risk stratification system identifies cases at highest risk of relapse

Comparisons between glucose analogue 2-deoxy-2-((18)F)fluoro-D-glucose and (18)F-sodium fluoride positron emission tomography/computed tomography in breast cancer patients with bone lesions

To compare 2-deoxy-2-((18)F)fluoro-D-glucose((18)F-FDG) and (18)F-sodium ((18)F-NaF) positron emission tomography/computed tomography (PET/CT) accuracy in breast cancer patients with clinically/radiologically suspected or known bone metastases

The evidence-based role of catecholaminergic PET tracers in Neuroblastoma. A systematic review and a head-to-head comparison with mIBG scintigraphy

Background: Molecular imaging is pivotal in staging and response assessment of children with neuroblastoma (NB). [123I]-metaiodobenzylguanidine (mIBG) is the standard imaging method; however, it is characterised by low spatial resolution, time-consuming acquisition procedures and difficult interpretation. Many PET catecholaminergic radiotracers have been proposed as a replacement for [123I]-mIBG, however they have not yet made it into clinical practice. We aimed to review the available literature comparing head-to-head [123I]-mIBG with the most common PET catecholaminergic radiopharmaceuticals. Methods: We searched the PubMed database for studies performing a head-to-head comparison between [123I]-mIBG and PET radiopharmaceuticals including meta-hydroxyephedrine ([11C]C-HED), 18F-18F-3,4-dihydroxyphenylalanine ([18F]DOPA) [124I]mIBG and Meta-[18F]fluorobenzylguanidine ([18F]mFBG). Review articles, preclinical studies, small case series (< 5 subjects), case reports, and articles not in English were excluded. From each study, the following characteristics were extracted: bibliographic information, technical parameters, and the sensitivity of the procedure according to a patient-based analysis (PBA) and a lesion-based analysis (LBA). Results: Ten studies were selected: two regarding [11C]C-HED, four [18F]DOPA, one [124I]mIBG, and three [18F]mFBG. These studies included 181 patients (range 5-46). For the PBA, the superiority of the PET method was reported in two out of ten studies (both using [18F]DOPA). For LBA, PET detected significantly more lesions than scintigraphy in seven out of ten studies. Conclusions: PET/CT using catecholaminergic tracers shows superior diagnostic performance than mIBG scintigraphy. However, it is still unknown if such superiority can influence clinical decision-making. Nonetheless, the PET examination appears promising for clinical practice as it offers faster image acquisition, less need for sedation, and a single-day examination