A prospective comparison of ACR-TIRADS and EU-TIRADS in thyroid nodule assessment for FNA-US

Diagnostic Performance of European and American College of Radiology Thyroid Imaging Reporting and Data System Classification Systems in Thyroid Nodules Over 20 mm in Diameter

OBJECTIVE

The challenge of selecting thyroid nodules for fine needle aspiration (FNA) cytology has led to the development of the Thyroid Imaging Reporting and Data System, primarily in 2 formats: European Thyroid Imaging Reporting and Data System (EU-TIRADS) and American College of Radiology Thyroid Imaging Reporting and Data System (ACR-TIRADS). Clinical observations suggest imperfect risk assessment for TIRADS 3 nodules ≥20 mm. This study aimed to evaluate the efficacy of TIRADS systems in distinguishing benign from malignant nodules in this subgroup.

METHODS

From May 2023 to March 2024, 1094 patients with thyroid nodules were referred for ultrasound at a University Hospital. Data on clinical, ultrasound, cytological, and histopathological parameters were collected. Nodules ≥20 mm were categorized by EU-TIRADS and ACR-TIRADS, and their predictive performance for malignancy was assessed through postthyroidectomy histopathology or FNA cytology (Bethesda classification).

RESULTS

Two hundred sixty-seven patients (mean age 60.3 ± 14.3 years; 46 men, 221 women) with 308 nodules were analyzed. Twenty-two malignancies and 286 benign nodules were recorded. Recalculating European Thyroid Imaging Reporting and Data System 3 performance using 25-mm and 30-mm thresholds (ACR-modified EU-TIRADS) avoided 24% and 41% of FNAs, respectively, while ACR-TIRADS would prevent 26.6% (P > .05). Two malignancies were missed.

CONCLUSION

EU-TIRADS and ACR-TIRADS show similar efficacy when using a 25 mm FNA threshold. Raising the cutoff for FNA in European Thyroid Imaging Reporting and Data System 3 nodules could reduce unnecessary procedures but may increase the risk of missed malignancies, impacting patient outcomes.

Meaning of ACR-TIRADS recommendation in favor of follow-up rather than FNAC in thyroid nodules

Thyroid Imaging Reporting and Data Systems (TIRADSs) have been largely diffused for their high accuracy in risk stratification of thyroid nodules (TNs) and their selection for fine-needle aspiration cytology (FNAC). The most popular TIRADSs are ACR-, EU-, and K-TIRADS, with some discrepancies each other. One major difference is that ACR-TIRADS includes a recommendation in favor of follow-up in TNs having a major diameter insufficient to indicate FNAC. The present study aimed to explore prevalence and significance of this recommendation. EU- and K-TIRADS were used as comparator. A retrospective series of thyroidectomies was searched according to a pre-defined protocol. The study period was 2019-2023. Preoperative ultrasound images were reviewed by radiologists blinded of clinical data. Matching of TIRADS and histology was performed later. Histology was the gold standard. The study series included 39 TNs classified as category 3, 4, or 5 and assessed for follow-up according to ACR-TIRADS. The overall cancer frequency was 25.6%, being 13% in category 3, 20% in category 4, and 83.3% in category 5. The category assessment according to ACR-, EU-, and K-TIRADS was not significantly different. EU-TIRADS indicated FNAC in 10 TNs of which two cancers and eight benign lesions. K-TIRADS recommended FNAC in 32 TNs of which seven cancers and 25 benign lesions. TNs assessed for follow-up according to ACR-TIRADS are cancer in one-fourth of cases. EU- and, especially, K-TIRADS allow us to select for FNAC cancers, with the burden of non-negligible frequency of unnecessary FNACs.

Effects of Implementation of European Thyroid Imaging Reporting and Data System Risk Stratification in a Thyroid Cancer Program in Western Sweden: A Retrospective Cohort Study

OBJECTIVE

The European Thyroid Imaging Reporting and Data System (EU-TIRADS) allows for selective fine needle aspiration cytology (FNAC). In 2017, EU-TIRADS was implemented as part of a nationwide standardized care bundle for thyroid cancer in Western Sweden with a population of approximately 1.7 million. The objective of this study was to investigate the clinical value of EU-TIRADS attempting to reduce the number of unnecessary FNACs in referred patients with thyroid nodules.

METHODS

The study cohort consisted of all patients referred to Sahlgrenska University Hospital due to a palpable, newly detected or growing thyroid nodules or a positron emission tomography-positive finding for examination with thyroid ultrasound and selective cytology between 2018 and 2022. Medical records on EU-TIRADS classification, corresponding FNAC results, and histopathologic diagnosis were retrospectively collected. Adherence to the EU-TIRADS guidelines, use of selective FNAC, and rate of malignancy in patients who underwent surgery were assessed.

RESULTS

In total, 1246 thyroid nodules in 990 patients were evaluated. The distributions of EU-TIRADS 2 to 5 (number [percentage]) for all examined nodules were 63 (5%), 462 (37%), 443 (36%), and 278 (22%), respectively. FNAC was omitted in 7% of the investigated patients. FNAC was performed in 124 nodules (10%) despite not fulfilling the EU-TIRADS criteria or absence of positron emission tomography-positive findings. The rate of malignancy was 33% and 1/50 in patients who underwent "unnecessary" FNAC.

CONCLUSION

Implementation of EU-TIRADS in routine management of thyroid nodules led to the selective use of FNAC; however, the clinical impact was limited. This study provides real-world data on the value and magnitude of diagnostic improvement by implementing EU-TIRADS in clinical practice.

Thyroid Nodule Characterization: Overview and State of the Art of Diagnosis with Recent Developments, from Imaging to Molecular Diagnosis and Artificial Intelligence

Ultrasound (US) is the primary tool for evaluating patients with thyroid nodules, and the risk of malignancy assessed is based on US features. These features help determine which patients require fine-needle aspiration (FNA) biopsy. Classification systems for US features have been developed to facilitate efficient interpretation, reporting, and communication of thyroid US findings. These systems have been validated by numerous studies and are reviewed in this article. Additionally, this overview provides a comprehensive description of the clinical and laboratory evaluation of patients with thyroid nodules, various imaging modalities, grayscale US features, color Doppler US, contrast-enhanced US (CEUS), US elastography, FNA biopsy assessment, and the recent introduction of molecular testing. The potential of artificial intelligence in thyroid US is also discussed.

Comparison the accuracy of thyroid sono-elastography vs. ultrasound-guided fine needle aspiration cytology with thyroid malignancy diagnosis histopathology

Objective. The intend of the present study was to assess the diagnostic performance of strain elastography in investigating the thyroid nodule malignancy taking the surgical biopsy as a gold standard reference test. Methods. The study included 120 patients with 123 thyroid nodules, of which 67 had total thyroidectomy. The American College of Radiology Thyroid Imaging Reporting and Data Systems (ACR-TIRADS) were evaluated for all nodules. All suspicious nodules were referred for a fine needle aspiration cytology (FNAC) if they fulfilled the required size. Strain elastography was performed for each suspicious nodule. Ultrasound-guided FNAC was performed for all suspicious nodules. Total thyroidectomy was performed in those whom the suspicious nodules were proven by FNAC. Results. Strain ratio had a sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of 84%, 81%, 95%, 85%, and 84%, respectively, with a cut point 1.96. Elasticity score had a sensitivity, specificity, PPV, NPV, and diagnostic accuracy of 100%, 80%, 95%, 85% and 87%, respectively, with a cut point 0.96. The elasticity score had a statistically significantly odds ratio for detecting the benignity 3.9 C. I (1.6-9.3). Conclusion. Strain elastography has a high diagnostic performance in detecting the malignant as well as benign nodules, thus it can limit the rate of unneeded FNAC or surgery especially among B3 and B4 groups with indeterminate cytology.

Age-related variation in malignant cytology rates of thyroid nodules: insights from a retrospective observational study assessing the ACR TI-RADS

OBJECTIVE

The influence of age on the malignant cytology rate of thyroid nodules remains uncertain. The American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) is currently used to guide subsequent investigations of thyroid nodules, regardless of clinical variables. This study aimed to investigate the impact of age on the malignant cytology rates of thyroid nodules and the diagnostic performance of ACR TI-RADS across different age groups.

DESIGN

A retrospective, single-center, observational study.

METHODS

Patients aged ≥ 20 years with thyroid nodules, who underwent fine-needle aspiration biopsy between 2012 and 2019 were evaluated. Ultrasound images were used to obtain the TI-RADS data. Malignancy was determined based on suspicious for malignancy (Bethesda V) and malignant (Bethesda VI) cytology results or malignancy in cell block analysis.

RESULTS

A total of 1023 nodules from 921 patients (88.2% female) were analyzed. The median age was 58.5 (interquartile range [IQR], 41.1-66.6) years, and the median nodule size was 2.4 (IQR, 1.7-3.6) cm. Stratification by age revealed a decreasing prevalence of malignant cytology across subgroups of 20-39, 40-59, and ≥60 years (10.7%, 8.5%, and 3.7%, respectively; P = .002). After adjusting for sex, multinodularity, nodule size, and ACR TI-RADS category, we observed that each year of age reduced the OR for malignant cytology by 3.0% (95% CI: 0.7%-5.3%; P = .011). When comparing the subgroups of 20-39 and ≥60 years, the malignant cytology rate decreased by half in TI-RADS 4 (from 21.4% to 10.4%) and two-thirds in TI-RADS 5 (from 64.7% to 22.6%).

CONCLUSIONS

Our study demonstrated that as patient age increased, the rate of malignant cytology in thyroid nodules decreased. Moreover, age significantly influences the malignancy rates of thyroid nodules classified according to the ACR TI-RADS.

Diagnostic efficiency among Eu-/C-/ACR-TIRADS and S-Detect for thyroid nodules: a systematic review and network meta-analysis

Background

The performance in evaluating thyroid nodules on ultrasound varies across different risk stratification systems, leading to inconsistency and uncertainty regarding diagnostic sensitivity, specificity, and accuracy.

Objective

Comparing diagnostic performance of detecting thyroid cancer among distinct ultrasound risk stratification systems proposed in the last five years.

Evidence acquisition

Systematic search was conducted on PubMed, EMBASE, and Web of Science databases to find relevant research up to December 8, 2022, whose study contents contained elucidation of diagnostic performance of any one of the above ultrasound risk stratification systems (European Thyroid Imaging Reporting and Data System[Eu-TIRADS]; American College of Radiology TIRADS [ACR TIRADS]; Chinese version of TIRADS [C-TIRADS]; Computer-aided diagnosis system based on deep learning [S-Detect]). Based on golden diagnostic standard in histopathology and cytology, single meta-analysis was performed to obtain the optimal cut-off value for each system, and then network meta-analysis was conducted on the best risk stratification category in each system.

Evidence synthesis

This network meta-analysis included 88 studies with a total of 59,304 nodules. The most accurate risk category thresholds were TR5 for Eu-TIRADS, TR5 for ACR TIRADS, TR4b and above for C-TIRADS, and possible malignancy for S-Detect. At the best thresholds, sensitivity of these systems ranged from 68% to 82% and specificity ranged from 71% to 81%. It identified the highest sensitivity for C-TIRADS TR4b and the highest specificity for ACR TIRADS TR5. However, sensitivity for ACR TIRADS TR5 was the lowest. The diagnostic odds ratio (DOR) and area under curve (AUC) were ranked first in C-TIRADS.

Conclusion

Among four ultrasound risk stratification options, this systemic review preliminarily proved that C-TIRADS possessed favorable diagnostic performance for thyroid nodules.

Systematic review registration

https://www.crd.york.ac.uk/prospero, CRD42022382818.

Recent Advances in the Surgical Management of Thyroid Cancer

A growing incidence of differentiated thyroid cancer (DTC) has been reported in most developed countries, corresponding mainly to incidentally discovered small papillary thyroid carcinomas. Given the excellent prognosis of most patients with DTC, optimal therapeutic management, minimizing complications, and preserving patient quality of life are essential. Thyroid surgery has a central role in both the diagnosis, staging, and treatment of patients with DTC. Thyroid surgery should be integrated into the global and multidisciplinary management of patients with DTC. However, the optimal surgical management of DTC patients is still controversial. In this review article, we discuss the recent advances and current debates in DTC surgery, including preoperative molecular testing, risk stratification, the extent of thyroid surgery, innovative surgical tools, and new surgical approaches.

Evaluation of the efficacy of EU-TIRADS and ACR-TIRADS in risk stratification of pediatric patients with thyroid nodules

BACKGROUND

Pediatric thyroid nodules have a lower prevalence but a higher rate of malignancy (ROM) than those in adults. Ultrasound features suspected of malignancy lead to fine needle aspiration biopsy (FNAB) and subsequent cytological determination, upon which management is decided. Based on the characteristics of ultrasound, to standardize clinician decisions and avoid unnecessary FNAB, the European Thyroid Association and the American Radiology College have established guidelines for Thyroid Imaging, Reporting and Data System (EU-TIRADS and ACR-TIRADS) for ROM stratification of thyroid nodules. The aim of this study is to evaluate the diagnostic performance of ACR-TIRADS and EU-TIRADS in pediatric age.

MATERIALS AND METHODS

Subjects younger than 18 years of age with thyroid nodules greater than 0.5 cm observed in the 2000-2020 period were included.

RESULTS

Data from 200 subjects were collected. The overall ROM was 13%, rising to 26% if nodules with a diameter >1 cm were considered. Patients with a malignant nodule were more likely to have a higher EU-TIRADS score (p=0.03). Missed cancer diagnoses were 26.9%. Using the EU-TIRADS system, 40% of FNABs could have been avoided, while this scoring system would have resulted in FNAB being performed in 12% of cases where the assessment of ultrasound features would not recommend FNAB. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 73.1%, 57.1%, 73.1%, and 50%, respectively. Even considering the ACR-TIRADS, a higher score correlated with a higher ROM (p<0.001). This system missed 6 diagnoses of cancer (23.1%). Using the ACR-TIRADS system, 45.3% of FNABs could have been avoided, while FNAB should have been performed in 12% of cases where it was not recommended by ultrasound characteristics. Sensitivity, specificity, PPV and NPV were 76.9%, 50%, 76.9%, and 42.9%, respectively.

CONCLUSION

The present study confirms the correspondence of the EU-TIRADS and ACR-TIRADS categories with respect to malignancy but indicates not entirely satisfactory performance compared to FNAB alone. However, the use of the two TIRADS systems should be encouraged in multicentre studies to increase their performance and establish paediatric-specific points in the scoring criteria.