Ultrasound imaging classifications of thyroid nodules for malignancy risk stratification and clinical management: state of the art

Thyroid Fine-Needle Aspiration: The Current and Future Landscape of Cytopathology

Thyroid cytology is a rapidly evolving field that has seen significant advances in recent years. Its main goal is to accurately diagnose thyroid nodules, differentiate between benign and malignant lesions, and risk stratify nodules when a definitive diagnosis is not possible. The current landscape of thyroid cytology includes the use of fine-needle aspiration for the diagnosis of thyroid nodules with the use of uniform, tiered reporting systems such as the Bethesda System for Reporting Thyroid Cytopathology. In recent years, molecular testing has emerged as a reliable preoperative diagnostic tool that stratifies patients into different risk categories (low, intermediate, or high) with varying probabilities of malignancy and helps guide patient treatment.

Impact of ultrasound elastography in evaluating Bethesda category IV thyroid nodules with histopathological correlation

Introduction

Fine needle aspiration (FNA) is the gold standard method recommended in the diagnosis of thyroid nodules. Bethesda IV cytology results are identified in 7-9% of nodules investigated through FNA, with reported malignancy rate in a wide range of 10-40%. The recommended treatment is either surgical or risk additional molecular testing before surgery. However, a large number of nodules belonging to this category (60-80%) are observed to be benign after surgical excision, which can put the patient at risk of unnecessary surgical morbidity. This study aimed to assess the diagnostic performance of conventional ultrasound, the ACR TI-RADS score and elastography in cases of Bethesda IV cytology on FNA.

Methods

We evaluated ninety-seven consecutive cases with Bethesda category IV results on FNA by using conventional B-mode ultrasound, qualitative strain or shear-wave elastography (Hitachi Preirus Machine, Hitachi Inc., Japan and Aixplorer Mach 30 Supersonic Imagine, Aix-en-Provence, France) and all nodules were classified according to the ACR TI-RADS system. Conventional ultrasound was used to categorize the nodules as potentially malignant based on the following features: hypoechogenicity, inhomogeneity, a taller than wide shape, irregular margins, presence of microcalcifications, an interrupted thyroid capsule and suspicious cervical lymph nodes. Elastography classified nodules with increased stiffness as suspicious for malignancy.

Results

We considered pathology results as the gold standard diagnosis, finding that 32 out of 97 nodules were carcinomas (33%) and 65 out of 97 were benign nodules (67%). The benign group included twenty cases of non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP). Finally, we compared ultrasound data with pathology results, which showed that nineteen out of the 32 malignant nodules presented with increased stiffness on elastography (p=0.0002). On conventional ultrasound, we found that microcalcifications (p=0.007), hypoechogenicity and irregular margins (p=0.006) are features which can distinguish between benign and malignant nodules with statistical significance.

Discussion

Integrating elastography as a parameter of the ACR TI-RADS score in the evaluation of Bethesda category IV nodules showed a sensitivity of 90.62% in detecting thyroid cancer cases (p=0.006). We can conclude that elastographic stiffness as an addition to high risk features observed on conventional ultrasound improves the detection of malignant nodules in cases with Bethesda IV cytology.

Diagnostic Efficiency of ACR-TIRADS Score for Differentiating Benign and Malignant Thyroid Nodules of Various Pathological Types

BACKGROUND Thyroid nodule prevalence reaches 65% in the general population. Hence, appropriate ultrasonic examination is key in disease monitoring and management. We investigated the American College of Radiology Thyroid Imaging Reporting and Data System (ACR-TIRADS) score for diagnosis of benign and malignant thyroid nodules and pathological types. MATERIAL AND METHODS A retrospective study was conducted. According to ultrasound images, ultrasonic characteristics of benign and malignant thyroid nodules and different pathological types were analyzed using ACR-TIRADS score, and diagnostic value was determined. AUCs were compared for tumor diagnosis and differentiation. RESULTS Overall, 1675 thyroid nodules from 1614 patients were included. AUC value of papillary thyroid carcinoma (PTC) diagnosed with ACR-TIRADS was highest (0.955 [95% CI=0.946-0.965]), while that of follicular thyroid carcinoma (FTC) was lowest (0.877 [95% CI=0.843-0.912]). FTC had the highest sensitivity (95.1%) and lowest specificity (64.8%). When the cut-off value was 5.5 points, accuracy of diagnosing PTC and anaplastic thyroid carcinoma (ATC) was highest, 80.5% and 78.7% respectively. Comparison of the multi-index prediction model constructed by multivariable logistic regression analysis and prediction model constructed by ACR-TIRADS score showed, when evaluating PTC and ATC, the multi-index model was better: AUCs of PTC were 0.966 vs 0.955, and AUCs of ATC were 0.982 vs 0.952, respectively, (P<0.05). CONCLUSIONS ACR-TIRADS score-based ultrasound examination of thyroid nodules aids diagnosis of benign and malignant thyroid nodules. TIRADS criteria favor diagnosis of PTC (and ATC) over FTC. ACR-TIRADS score can help clinicians diagnose thyroid nodules quickly and earlier, exhibits good clinical value, and can prevent missed diagnoses.

The Incidence of Thyroid Cancer in Bethesda III Thyroid Nodules: A Retrospective Analysis at a Single Endocrine Surgery Center

BACKGROUND

Fine-needle aspiration cytology (FNAC) is widely used to diagnose and monitor thyroid nodules. The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) is the standard for interpreting FNAC specimens. The risk of malignancy in Bethesda III nodules, also known as Atypia of Undetermined Significance (AUS), varies significantly throughout several studies published worldwide. This retrospective study examines the risk of cancer in thyroid FNAC categorized as Bethesda III as identified in the final histopathology of thyroidectomy specimens at a single endocrine surgery center.

METHODS

This retrospective cohort analysis included 1038 consecutive patients who underwent elective thyroid surgery with complete follow-up data between January 2020 and March 2024. Preoperative data on clinical and pathological characteristics have been collected. The final histopathology report from the thyroidectomy specimen was compared to the results of the preoperative FNAC on nodules that were judged to be Bethesda category III. Statistical methods were performed using SPSS version 29.

RESULTS

A total of 670 ultrasound-guided FNACs (64.5%) performed during the study period were included in the final analysis. The study population was predominantly female, represented by 79.6% of patients with a mean age of 42.5 (SD 12.1), while 20.4% were male and significantly older with mean age of 45.13 years (p = 0.02). The FNAC inadequacy rate was 5.1%, which was associated with a high risk of malignancy (6 out of 34; 17.6%). Out of the total sample size of 170 patients classified as group III, 57 were found to have malignancies in final surgical histopathology, representing 33.5% of the cases within this category. The secondary gender-related outcome analysis showed that female patients classified under the Bethesda II category had a significantly higher risk of malignancy, with a rate of 21.2%, compared to males who had a malignancy rate of 3.4% in the same Bethesda category (p = 0.001, chi-square test). However, the female patients exhibited prognostically superior non-invasive tumors compared to male individuals (p = 0.02, chi-square test).

CONCLUSION

This study's results indicate that Bethesda categories II and III are associated with a higher risk of malignancy in comparison to the reports of the first and third editions of the TBSRTC, particularly for female patients classified under category II.

Diagnostic Performance of ACR TI-RADS and ATA Guidelines in the Prediction of Thyroid Malignancy: A Prospective Single Tertiary Center Study and Literature Review

AIM

This study sought to compare two common risk stratification systems in terms of their diagnostic performance for the evaluation of thyroid malignancy.

METHODS

The American College of Radiology (ACR) Thyroid Imaging, Reporting and Data System (TI-RADS) and the American Thyroid Association (ATA) guidelines were compared among 571 thyroid nodules with definitive fine needle aspiration (FNA) cytology or postoperative histopathology. Ultrasound characteristics such as composition, echogenicity, shape, margin, size, and vascularity were assessed for each thyroid nodule. Diagnostic performance measures were determined and compared through receiver operating characteristic (ROC) curves, and decision curve analysis (DCA).

RESULTS

Of 571 nodules, 65 (11.4%) were malignant. The AUC, sensitivity, specificity, positive predictive value, and negative predictive value were 0.691, 49.2%, 84.9%, 29.6%, and 92.8% for ATA guideline, and 0.776, 72.3%, 79.2%, 30.9%, and 95.7%, for ACR TI-RADS, respectively. ACR TI-RADS was more sensitive (p = 0.003), while the ATA guideline was more specific (p < 0.001). DCA demonstrated that the ACR TI-RADS provided a greater net benefit than the ATA guideline. In addition, the net reduction in unnecessary biopsies is higher for ACR TI-RADS than ATA guidelines. The total number of indicated biopsies and unnecessary FNA rates were lower in ACR TI-RADS compared to ATA guideline (293 vs. 527 and 80.2 vs. 87.8). ACR TI-RADS presented no biopsy indication in seven malignant nodules (all categorized as TR2), whereas ATA guideline missed one. Hypoechogenicity was the most significant predictor of malignancy (OR = 8.34, 95% CI: 3.75-19.45), followed by a taller-than-wide shape (OR = 6.73, 95% CI: 3.07-14.77).

CONCLUSIONS

Our findings suggest that each system has particular advantages in the evaluation of thyroid nodules. ACR TI-RADS reduces unnecessary FNA rates, however, malignant nodules categorized as TR2 might be missed using this system. Further evaluation of this group of nodules using Doppler and other ultrasound modalities is recommended.

Performance of ACR TI-RADS and the Bethesda System in Predicting Risk of Malignancy in Thyroid Nodules at a Large Children's Hospital and a Comprehensive Review of the Pediatric Literature

While thyroid nodules are less common in children than in adults, they are more frequently malignant. However, pediatric data are scarce regarding the performance characteristics of imaging and cytopathology classification systems validated to predict the risk of malignancy (ROM) in adults and select those patients who require fine-needle aspiration (FNA) and possibly surgical resection. We retrospectively reviewed the electronic medical records of all patients 18 years of age or younger who underwent thyroid FNA at our institution from 1 July 2015 to 31 May 2022. Based on surgical follow-up from 74 of the 208 FNA cases, we determined the ROM for the American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) ultrasound risk stratification system and The Bethesda System for Reporting Thyroid Cytopathology and added our results to those of pediatric cohorts from other institutions already published in the literature. We found the following ROMs for 1458 cases using ACR TI-RADS (TR): TR1. Benign: 2.2%, TR2. Not Suspicious: 9.3%, TR3. Mildly Suspicious: 16.6%, TR4. Moderately Suspicious: 27.0%, and TR5. Highly Suspicious 76.5%; and for 5911 cases using the Bethesda system: Bethesda I. Unsatisfactory: 16.8%, Bethesda II. Benign: 7.2%, Bethesda III: Atypia of Undetermined Significance: 29.6%, Bethesda IV. Follicular Neoplasm: 42.3%, Bethesda V. Suspicious for Malignancy: 90.8%, and Bethesda VI. Malignant: 98.8%. We conclude that ACR TI-RADS levels imply higher ROMs for the pediatric population than the corresponding suggested ROMs for adults, and, in order to avoid missing malignancies, we should consider modifying or altogether abandoning size cutoffs for recommending FNA in children and adolescents whose thyroid glands are smaller than those of adults. The Bethesda categories also imply higher ROMs for pediatric patients compared to adults.

Ultrasound elastography in chronic kidney disease: a systematic review and meta-analysis

Ultrasound elastography (USE) is a noninvasive technique for assessing tissue elasticity, and its application in nephrology has aroused growing interest in recent years. The purpose of this article is to systematically review the clinical application of USE in patients with chronic kidney disease (CKD), including native and transplanted kidneys, and quantitatively investigate differences in elasticity values between healthy individuals and CKD patients. Furthermore, we provide a qualitative analysis of the studies included, discussing the potential interplay between renal stiffness, estimated glomerular filtration rate, and fibrosis. In January 2022, a systematic search was carried out on the MEDLINE (PubMed) database, concerning studies on the application of USE in patients with CKD, including patients with transplanted kidneys. The results of the included studies were extracted by two independent researchers and presented mainly through a formal narrative summary. A meta-analysis of nine study parts from six studies was performed. A total of 647 studies were screened for eligibility and, after applying the exclusion and inclusion criteria, 69 studies were included, for a total of 6728 patients. The studies proved very heterogeneous in terms of design and results. The shear wave velocity difference of - 0.82 m/s (95% CI: - 1.72-0.07) between CKD patients and controls was not significant. This result agrees with the qualitative evaluation of included studies that found controversial results for the relationship between renal stiffness and glomerular filtration rate. On the contrary, a clear relationship seems to emerge between USE values and the degree of fibrosis. At present, due to the heterogeneity of results and technical challenges, large-scale application in the monitoring of CKD patients remains controversial.

Diagnostic performance of the EU TI-RADS and ACR TI-RADS scoring systems in predicting thyroid malignancy

INTRODUCTION

Several ultrasound scoring systems have been developed to stratify the risk of malignancy of thyroid nodules, including ACR (American College of Radiology) and EU (European) TI-RADS. This study aimed to assess the diagnostic performance of these two classifications using histology as a reference standard.

METHODS

It was a single-centre, retrospective study including 156 patients who underwent thyroidectomy. Ultrasound data of 198 nodules (99 malignant nodules and 99 benign nodules) were analysed. Both classifications were applied for all nodules.

RESULTS

Ultrasound criteria associated with malignancy were solid composition (OR=7.81; p < 10^-3 ), hypoechoic character (OR=16.42; p < 10^-3 ), irregular contours (OR=7.47; p < 10^-3 ), taller-than-wide shape (OR=3.58; p = 0.02), microcalcifications (OR=3.02; p = .006) and the presence of cervical adenopathy (OR=3.89; p = .006). The prevalence of malignancy was 15.5%, 69% and 76.9% for EU TI-RADS categories 3, 4 and 5, respectively. It was 33.3%, 57% and 91.1% for ACR TI-RADS categories 3, 4 and 5, respectively. For category 5, EU TI-RADS and ACR TI-RADS had sensitivities of 60% and 41%, specificities of 82% and 96%, respectively. For categories 4 and 5 combined, the diagnostic performance of these two classification systems became comparable with a sensitivity of 89% and 86% for EU-TIRADS and ACR-TIRADS, respectively. The area under the ROC curve was 0.81 for the EU TI-RADS classification and 0.82 for the ACR TI-RADS classification.

CONCLUSIONS

EU TI-RADS and ACR TI-RADS scoring systems seem to be comparable in predicting malignancy in thyroid nodules.

The Size of a Thyroid Nodule with ACR TI-RADS Does Not Provide a Better Prediction of the Nature of the Nodule: A Single-Center Retrospective Real-Life Observational Study

We investigated if thyroid nodule size has a predictive value of malignancy on a par with composition, echogenicity, shape, margin, and echogenic foci, and what would be the consequence of observing the rule of the American College of Radiology (ACR) to perform a fine-needle aspiration biopsy (FNAB). We conducted a retrospective real-life observational study on 86 patients who underwent surgery after a standardized diagnostic protocol. We divided the TR3, TR4, and TR5 classes into sub-classes according to the size threshold indicating FNAB (a: up to the threshold for no FNAB; b: over the threshold for FNAB suggested). We computed sensitivity, specificity, and positive (PPV) and negative predictive value (NPV) for the different sub-classes and Youden's index (Y) for the different possible cutoffs. Each sub-class showed the following PPV (0.67, 0.68, 0.70, 0.78, 0.72), NPV (0.56, 0.54, 0.51, 0.52, 0.59), and Y (0.20, 0.20, 0.22, 0.31, 0.30). In this real-life series, we did not find a significant difference in prediction of malignancy between the sub-categories according to the size threshold. All nodules have a pre-evaluation likelihood of being malignant, and the impact and utility of size thresholds may be less clear than suggested by the ACR TIRADS guidelines in patients undergoing standardized thyroid work up.

Patients undergoing endocrine consultation and first diagnosis of nodular disease: Indications of thyroid ultrasound and completeness of ultrasound reports

PURPOSE

To evaluate reasons for performing ultrasonography (US) and completeness of US reports in patients undergoing endocrine consultation with the first diagnosis of nodular disease.

METHODS

Since January 1 to June 30, 2021, we prospectively collected patient data (age and thyroid-stimulating hormone concentrations), reasons for performing thyroid US, and completeness of reports regarding the description of the thyroid gland and nodules. In the case of multiple nodules, we considered the nodule suspected of malignancy and the largest one. To evaluate the accuracy of thyroid nodule description, we referred to the five characteristics suggested by the ACR TI-RADS system.

RESULTS

A total of 341 patients with thyroid nodules received endocrine consultation (female, 78%). The most frequent reasons for performing thyroid US were unrelated to a suspected thyroid disease (31.7%), followed by incidentaloma (23.5%), dysfunction or positivity for thyroid antibodies (19.1%), symptomatic or visible nodules (17.6%), and family history of any thyroid disease (8.2%). Gland texture was not reported in 41.9%. The depth of the lobes was the dimension reported most frequently (42.2%), but any diameter was not reported in 57.8% of the cases. As regards the description of the most relevant nodule, length was reported more frequently (75.9%). Margins and echogenicity were more frequently described (54.5% and 44.3%, respectively) than other characteristics (composition: 27%; shape: 8.8%; echogenic foci: 6.7%). No reports had indicated the malignancy risk stratification.

CONCLUSIONS

The results of the study demonstrate that in patients undergoing endocrine consultation with first detected thyroid nodules, US was mostly performed in asymptomatic cases, US reports were incomplete, and no risk stratification system was reported.

Diagnostic Value of AngioPLUS Microvascular Imaging in Thyroid Nodule Diagnosis Using Quantitative and Qualitative Vascularity Grading

This study investigated the diagnostic value of the Angio Planewave Ultrasensitive (AngioPLUS) Doppler ultrasound in improving the efficacy of grey scale ultrasound in thyroid nodule diagnosis. The EU TIRADS was used for the grey scale ultrasound assessment of 94 thyroid nodules. conventional Doppler and AngioPLUS Doppler ultrasound images were evaluated using qualitative vascularity grading, where predominant central vascularity indicated malignancy-suspicion, and quantitative regional vascularity assessment, where predominant peripheral vascularity using a ratio vascularity index (RVI) of > 1 indicated benign disease. Diagnostic performance outcomes of sole and combination approaches were calculated based on final pathologic results. Using sole EU TIRADS and AngioPLUS + power Doppler imaging (APDI) based on qualitative vascularity and RVI, the results were a sensitivity of 83.3% vs. 83.3 vs. 66.7% and a specificity of 50% vs. 81.3% vs. 73.4, respectively. EU TIRADS combined with APDI significantly improved the specificity using both qualitative vascularity and RVI assessment approaches (84.4% and 81%, respectively, p < 0.05); and slightly reduced the sensitivity (76.7% and 58.1%). For cytologically-equivocal thyroid nodules, the combination approach using qualitative vascularity assessment outperformed the EU TIRADS (sensitivity: both were 88.9%; specificity: 77.4% vs. 38.7%, p < 0.05; and AUROC: 0.83 vs. 0.62, p < 0.05). APDI combined with EU TIRADS is diagnostically efficient in stratifying thyroid nodules, particularly cytologically-equivocal nodules.

A rare case of unilateral vocal cord paralysis: neurovascular conflict due to an aberrant bronchial artery detected at computed tomography

We report the case of a 29-year-old patient without medical history presenting with dysphonia associated with left unilateral vocal cord paralysis. The patient underwent a contrast-enhanced computed tomography with an angiographic arterial phase of the head, neck and chest, and the only significant finding was the presence of a large, aberrant right bronchial artery originating directly from the aortic arch, where the recurrent left laryngeal nerve loops. After excluding alternative etiologies, the hypothesis of neurovascular conflict between this vessel and the recurrent left laryngeal nerve was formulated. To the best of our knowledge, this is the first case reported in the literature. Thanks to its high spatial resolution, contrast-enhanced computed tomography is the examination of choice for the study of anatomical variants and should be included in the routine work-up of patients presenting with unilateral vocal cord paralysis.

Contrast-Enhanced Ultrasonography for Differential Diagnosis of Benign and Malignant Thyroid Lesions: Single-Institutional Prospective Study of Qualitative and Quantitative CEUS Characteristics

Objectives

To extend and revise the diagnostic value of contrast-enhanced ultrasonography (CEUS) for differentiation between malignant and benign thyroid nodules.

Methods

This single-institution prospective study aims to compare CEUS qualitative and objective quantitative parameters in benign and malignant thyroid nodules. Consecutive cohort of 100 patients was examined by CEUS, 68 out of them were further analysed in detail. All included patients underwent cytological and/or histopathological verification of the diagnosis.

Results

Fifty-five (81%) thyroid nodules were benign, and 13 (19%) were malignant. Ring enhancement pattern was strongly associated with a benign aetiology (positive predictive value 100%) and heterogeneous enhancement pattern with malignant aetiology (positive predictive value 72.7%). The shape of the TIC (time-intensity curve) was more often identical in the benign lesion (98.2%) than in malignant lesions (69.2%), p=0.004.

Conclusions

This study indicates that CEUS enhancement patterns were significantly different in benign and malignant lesions. Ring enhancement was a very strong indicator of benign lesions, whereas heterogeneous enhancement was valuable to detect malignant lesions.

Immune response pathways enriched in breast cancer samples with brain metastasis

BACKGROUND

Breast cancer (BC) is the most common form of cancer in women. BC brain metastasis (BM) is associated with poor prognosis, especially for Triple negative breast cancer (TNBC). However, the driver genes of this clinical characteristic are poorly understood.

METHODS

This study conducted a transcriptome-wide analysis of gene expression levels in BCBM samples from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) datasets. Clinical data and gene expression matrix of TNBC samples were collected. Differential analysis and functional enrichment of metastasis vs. non metastasis data samples were conducted. Genes associated with overall survival and BM event was scanned.

RESULTS

Up-regulation in 120 genes and down-regulation in 56 genes were found in TNBC metastasis data. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) clustering using expression alternated genes showed unique immune-gene enrichment in BM samples. Immune response category GO:000695 was found as the most significant term associated with metastasis event. KEGG pathways including cytokine pathways and Primary immunodeficiency were significantly changed in metastasis samples. ESR1 and FYB2 genes expression changes were found to be linked to survival or BM events.

CONCLUSIONS

Our results suggest that data-mining on the immune microenvironment of BM might be useful in future study.

The role of ultrasound measurements and cosmetic scoring in evaluating the effectiveness of ethanol ablation in cystic thyroid nodules

BACKGROUND

A minimally invasive approach has been adopted to treat benign cystic nodules in recent years, with ethanol ablation (EA) being used as a more common method in routine treatment. For this study, we aimed to investigate the change of nodule volumes and cosmetic scores before and after EA in benign thyroid nodules and the effectiveness of treatment. Therefore, ultrasound data and cosmetic scores of pure cystic, mixed-type and spongy-type benign thyroid nodules undergoing EA in the last two years were reviewed retrospectively.

METHODS

Archive scanning was performed for all cases that were proven benign by fine-needle aspiration biopsy (FNAB) and who underwent EA. In all 46 patients included in the study, thyroid FNAB was performed. Ultrasound images were available to assess the size and volumes at pretreatment and 3 and 6 months after EA. The cosmetic scores obtained before the procedure and at 6 months after EA were compared.

RESULTS

There was a statistically significant difference when the sizes and volumes of the nodules were compared at pretreatment, 3 and 6 months follow-up (P < .001). The mean pretreatment cosmetic score was 3.09, and at 6 months, it was 1.20, with a statistically significant difference (P < .001).

CONCLUSIONS

Recently, a minimally invasive approach has been adopted in the treatment of benign cystic nodules, with ethanol ablation becoming more common in routine treatment. Therefore, ethanol ablation is very valuable in minimising complications that may arise from surgery.

Diagnostic Performance of Kwak, EU, ACR, and Korean TIRADS as Well as ATA Guidelines for the Ultrasound Risk Stratification of Non-Autonomously Functioning Thyroid Nodules in a Region with Long History of Iodine Deficiency: A German Multicenter Trial

Germany has a long history of insufficient iodine supply and thyroid nodules occur in over 30% of the adult population, the vast majority of which are benign. Non-invasive diagnostics remain challenging, and ultrasound-based risk stratification systems are essential for selecting lesions requiring further clarification. However, no recommendation can yet be made about which system performs the best for iodine deficiency areas. In a German multicenter approach, 1211 thyroid nodules from 849 consecutive patients with cytological or histopathological results were enrolled. Scintigraphically hyperfunctioning lesions were excluded. Ultrasound features were prospectively recorded, and the resulting classifications according to five risk stratification systems were retrospectively determined. Observations determined 1022 benign and 189 malignant lesions. The diagnostic accuracies were 0.79, 0.78, 0.70, 0.82, and 0.79 for Kwak Thyroid Imaging Reporting and Data System (Kwak-TIRADS), American College of Radiology (ACR) TI-RADS, European Thyroid Association (EU)-TIRADS, Korean-TIRADS, and American Thyroid Association (ATA) Guidelines, respectively. Receiver Operating Curves revealed Areas under the Curve of 0.803, 0.795, 0.800, 0.805, and 0.801, respectively. According to the ATA Guidelines, 135 thyroid nodules (11.1%) could not be classified. Kwak-TIRADS, ACR TI-RADS, and Korean-TIRADS outperformed EU-TIRADS and ATA Guidelines and therefore can be primarily recommended for non-autonomously functioning lesions in areas with a history of iodine deficiency.

The Role of Metabolic Volumetric Parameters in Predicting Malignancy in Incidental Thyroid Nodules Detected in 18F-FDG PET/CT Scans

Objectives

The metabolic activities of tumors can be calculated volumetrically during positron emission tomography/computed tomography (PET/CT) imaging using metabolic tumor volume (MTV) and total lesion glycolysis (TLG). This study aimed to evaluate the roles of MTV and TLG in predicting the malignancy risk of incidental thyroid nodules detected by PET/CT imaging.

Methods

Active metabolic areas of each section were manually drawn by region of interest to calculate the MTV of nodules, and all obtained values were then summed. TLG, the product of mean standardized uptake value and MTV, was calculated by multiplying two values. All participants underwent thyroid ultrasonography imaging. All nodules were divided into risk classes according to the European Thyroid Image Reporting and Data System (EU-TIRADS) that was developed by the European Thyroid Association. The American Thyroid Association Guidelines were used to determine which thyroid nodules would undergo thyroid fine-needle biopsy (FNAB). Results were classified according to the Bethesda scoring system.

Results

TLG levels were significantly higher in malignant or malignant-suspicious nodules than in benign nodules (p=0.013). Although MTV levels were high in malignant or malignant-suspicious nodules than in benign and non-diagnostic nodules, it was statistically insignificant at limit values (p=0.079). Areas under curve (AUC) were 0.726 (p=0.005) and AUC: 0.668 (p=0.039) for TLG and MTV, respectively. The 2.3 g cut-off value of TLG has a sensitivity of 85.7% and specificity of 59.0%. The 1.7 mL cut-off value of MTV has a sensitivity of 78.6% and specificity of 60.4%.

Conclusion

We believe that TLG evaluation will be useful in predicting high-risk malignancy or malignancy suspicion based on EU-TIRADS risk classification of incidental thyroid nodules detected in PET/CT images. We believe that unnecessary thyroid FNABs can be avoided for thyroid incidental nodules if such relation and cut-off values are determined and that it will be useful in hastening the operation of the necessary patients.

Combining real-time elastography with fine-needle aspiration biopsy to identify malignant thyroid nodules

Objectives

To evaluate the diagnostic performance of real-time elastography (RTE) combined with fine-needle aspiration (FNA) biopsy in identifying malignant thyroid nodules.

Methods

This was a single-centre, retrospective study and involved patients who had underogone partial or total thyroidectomy from 01 January 2014 to 31 December 2018 at our centre. Eligible patients were at least18 years of age, had reliable grayscale ultrasound imaging results, a RTE evaluation and had undergone a FNA biopsy.

Results

Data were available from 437 patients. A high RTE score was a significant independent risk factors for malignancy. RTE plus FNA biopsy increased diagnostic accuracy compared with either method alone and the sensitivity and specificity of the combined model were 86% and 78%, respectively.

Conclusions

The combination of RTE imaging with FNA biopsy improves the diagnostic performance in differentiating benign and malignant thyroid nodules.

The value of the Demetics ultrasound-assisted diagnosis system in the differential diagnosis of benign from malignant thyroid nodules and analysis of the influencing factors

OBJECTIVES

To evaluate the value of Demetics and to explore whether Demetics can help radiologists with varying years of experience in the differential diagnosis of benign from malignant thyroid nodules.

METHODS

The clinical application value of Demetics was assessed by comparing the diagnostic accuracy of radiologists before and after applying Demetics. This retrospective analysis included 284 thyroid nodules that underwent pathological examinations. Two different combined methods were applied. Using method 1: the original TI-RADS classification was forcibly upgraded or downgraded by one level when Demetics classified the thyroid nodules as malignant or benign. Using method 2: the TI-RADS and benign or malignant classification of the thyroid nodules were flexibly adjusted after the physician learned the Demetics' results.

RESULTS

Demetics exhibited a higher sensitivity than did junior radiologist 1 (p_D1 = 0.029) and was similar in sensitivity to the two senior radiologists. Demetics had a higher AUC than both junior radiologists (p_D1 = 0.042, p_D2 = 0.038) and an AUC similar to that of the senior radiologists. The sensitivity (p = 0.035) and AUC (p = 0.031) of junior radiologist 1 and the specificity (p < 0.001) and AUC (p = 0.026) of junior radiologist 2 improved with combined method 1. The AUC of junior radiologist 2 improved with combined method 2 (p = 0.045). The factors influencing the diagnostic results of Demetics include sonographic signs (echogenicity and echogenic foci), contrast of the image, and nodule size.

CONCLUSION

Demetics exhibited high sensitivity and accuracy in the differential diagnosis of benign from malignant thyroid nodules. Demetics could improve the diagnostic accuracy of junior radiologists.

KEY POINTS

• Demetics exhibited a high sensitivity and accuracy in the differential diagnosis of benign from malignant thyroid nodules. • Demetics could improve the diagnostic accuracy of junior radiologists in the differential diagnosis of benign from malignant thyroid nodules. • Factors influencing the diagnostic results of Demetics include the sonographic signs (echogenicity and echogenic foci), contrast of the image, and nodule size.

Diagnostic performance evaluation of different TI-RADS using ultrasound computer-aided diagnosis of thyroid nodules: An experience with adjusted settings

BACKGROUND

Thyroid cancer diagnosis has evolved to include computer-aided diagnosis (CAD) approaches to overcome the limitations of human ultrasound feature assessment. This study aimed to evaluate the diagnostic performance of a CAD system in thyroid nodule differentiation using varied settings.

METHODS

Ultrasound images of 205 thyroid nodules from 198 patients were analysed in this retrospective study. AmCAD-UT software was used at default settings and 3 adjusted settings to diagnose the nodules. Six risk-stratification systems in the software were used to classify the thyroid nodules: The American Thyroid Association (ATA), American College of Radiology Thyroid Imaging, Reporting, and Data System (ACR-TIRADS), British Thyroid Association (BTA), European Union (EU-TIRADS), Kwak (2011) and the Korean Society of Thyroid Radiology (KSThR). The diagnostic performance of CAD was determined relative to the histopathology and/or cytology diagnosis of each nodule.

RESULTS

At the default setting, EU-TIRADS yielded the highest sensitivity, 82.6% and lowest specificity, 42.1% while the ATA-TIRADS yielded the highest specificity, 66.4%. Kwak had the highest AUROC (0.74) which was comparable to that of ACR, ATA, and KSThR TIRADS (0.72, 0.73, and 0.70 respectively). At a hyperechoic foci setting of 3.5 with other settings at median values; ATA had the best-balanced sensitivity, specificity and good AUROC (70.4%; 67.3% and 0.71 respectively).

CONCLUSION

The default setting achieved the best diagnostic performance with all TIRADS and was best for maximizing the sensitivity of EU-TIRADS. Adjusting the settings by only reducing the sensitivity to echogenic foci may be most helpful for improving specificity with minimal change in sensitivity.

Systems of Risk Stratification of Malignancy by Ultrasound of Thyroid Nodules

Thyroid nodules (TN) are more frequently identified with the use of thyroid ultrasonography, and they have a low risk of malignancy. Ultrasonographic features have been established that increase the probability of being faced with thyroid carcinoma; however, individually, these characteristics do not perform adequately in the diagnosis of malignancy, limiting their usefulness when indicating cytological studies by means of fine-needle aspiration (FNC). This situation motivated the development of risk stratification systems for thyroid nodules, which unified their ultrasound characteristics, with the aim of establishing risk categories, standardizing the preparation of reports, and providing the clinician with useful tools to define the surveillance option or form invasive studies.

The objective of this review is to compare the different systems developed by some scientific societies for the stratification of thyroid nodules, with respect to their predictive capacities for malignancy, their operational characteristics for diagnosis, and, to suggest recommendations for the implementation of these systems, placing emphasis on those with the best ability to reduce the performance of unnecessary invasive studies and to guide decision-making in the face of undetermined cytological results.

Detection of STRN-ALK fusion in thyroid nodules with indeterminate cytopathology facilitates papillary thyroid cancer diagnosis

Thyroid cancer is the most common endocrine malignancy. Approximately 70% of cases of papillary thyroid carcinoma and 50% of poorly differentiated and anaplastic thyroid carcinoma harbor well-characterized driver mutations and chromosomal rearrangements that drive tumorigenesis. Molecular profiling has been helpful in identifying and informing follow-up strategies in tumors with more aggressive trajectories. Here, we report a case of papillary thyroid cancer (PTC) discovered in a patient with thyroid nodules with relatively benign ultrasound and fine needle aspiration (FNA) findings. Molecular testing in this patient identified a rare STRN-ALK fusion in two thyroid nodules with indeterminate and/or benign cytology. This led to the patient undergoing a thyroid lobectomy and a subsequent confirmation of papillary thyroid carcinoma upon resection. The report highlights the role of comprehensive molecular testing in thyroid lesions of indeterminate cytology.

Evaluation of vitamin D receptor gene polymorphisms in patients with differentiated thyroid carcinomas and nodular goiter

BACKGROUND

The role of vitamin D has previously been determined in autoimmune and malignant thyroid diseases. We aimed to identify the haplotype distribution of single nucleotide polymorphisms (SNPs) in the vitamin D receptor (VDR) gene, which has been suggested to play a role in the pathogenesis of differentiated thyroid cancers and benign thyroid diseases.

METHODS

Two hundred and sixteen patients, 113 with benign and 103 with differentiated thyroid cancers, together with the same number of healthy controls, were included in the study. FokI, BsmI, ApaI, and TaqI SNPs in VDR were analyzed in all participants using the PCR-RFLP method.

RESULTS

When the patients with differentiated thyroid cancers or the patients with nodular goiter and control cases were compared for BsmI, ApaI or TaqI polymorphisms, three genotype distributions (BB, Bb, bb; AA, Aa, aa; TT, Tt, tt) were found to not differ significantly. When the patients with differentiated thyroid cancers and control cases were compared for the FokI polymorphism in the VDR gene, the three genotype distributions (FF, Ff, ff) did not differ. However, in patients with nodular goiter, the FF genotype in the FokI polymorphism of the VDR gene was found to be statistically significantly higher (P=0.033).

CONCLUSIONS

This is the first study in the literature evaluating the role of VDR gene SNPs in nodular goiter. We can suggest that SNP distribution in the VDR gene is not associated with malignancy but may cause some alterations in thyrocyte morphology and functions.

False-Positive Malignant Diagnosis of Nodule Mimicking Lesions by Computer-Aided Thyroid Nodule Analysis in Clinical Ultrasonography Practice

This study aims to test computer-aided diagnosis (CAD) for thyroid nodules in clinical ultrasonography (US) practice with a focus towards identifying thyroid entities associated with CAD system misdiagnoses. Two-hundred patients referred to thyroid US were prospectively enrolled. An experienced radiologist evaluated the thyroid nodules and saved axial images for further offline blinded analysis using a commercially available CAD system. To represent clinical practice, not only true nodules, but mimicking lesions were also included. Fine needle aspiration biopsy (FNAB) was performed according to present guidelines. US features and thyroid entities significantly associated with CAD system misdiagnosis were identified along with the diagnostic accuracy of the radiologist and the CAD system. Diagnostic specificity regarding the radiologist was significantly (p < 0.05) higher than when compared with the CAD system (88.1% vs. 40.5%) while no significant difference was found in the sensitivity (88.6% vs. 80%). Focal inhomogeneities and true nodules in thyroiditis, nodules with coarse calcification and inspissated colloid cystic nodules were significantly (p < 0.05) associated with CAD system misdiagnosis as false-positives. The commercially available CAD system is promising when used to exclude thyroid malignancies, however, it currently may not be able to reduce unnecessary FNABs, mainly due to the false-positive diagnoses of nodule mimicking lesions.

US-based risk stratification "guidelines" for thyroid nodules: Quō Vādis?

PURPOSE

This rapid scoping review addresses the commentary titled the ACR TI-RADS™: An Advance in the Management of Thyroid Nodules or Pandora's Box of Surveillance? suggesting that the 2017 American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS™-2017) adds to a plethora of existing guidelines, incorporates an inconsistent lexicon, and potentially contradicts recommendations.

MATERIALS AND METHODS

The author performed a rapid scoping review using a combination of English keywords to identify and review peer reviewed articles contained in electronic databases (e-databases) comparing 2 or more guidelines for managing adult thyroid nodules (GMTNs) with (UGMTNs) and without (non-UGMTNs) ultrasound. E-databases included Medline (PubMed), EBSCO, Google, and Google Scholar published (2010-2019).

RESULTS

The search returned 28 articles, where the author identified 12 different guidelines. Most articles evaluated diagnostic performance (N = 26), not quality (N = 2) measures. The most commonly reviewed UGMTNs were in descending order ATA-2015, ACR TI-RADS™-2017, South Korean, and EU TI-RADS. No article reviewed all GMTNs or identified a generally accepted UGMTNs or non-UGMTNs. Primary origin continents were: North America (U.S.A), Asia (Japan, South Korea, Thailand), Europe (France, Italy, U.K.), and South America (Chile).

CONCLUSION

A plethora of UGMTNs may exist. No guideline enjoys general acceptance and evaluations of performance and quality vary.