Application of Thyroid Imaging Reporting and Data System in the Ultrasound Assessment of Thyroid Nodules According to Physician Experience

Diagnostic Performance of ACR and Kwak TI-RADS for Benign and Malignant Thyroid Nodules: An Update Systematic Review and Meta-Analysis

(1) Background: To determine the optimal cut-off values of two risk stratification systems to discriminate malignant thyroid nodules and to compare the diagnostic performance; (2) Methods: True and false positive and negative data were collected, and methodological quality was assessed for forty-six studies involving 39,085 patients; (3) Results: The highest area under the receiver operating characteristic (ROC) curve (AUC) of ACR and Kwak TI-RADS were 0.875 and 0.884. Based on the optimal sensitivity and specificity, the highest accuracy values of ROC curves or diagnostic odds ratios (DOR) were taken as the cut-off values for TR4 (moderate suspicious) and 4B. The sensitivity, specificity, DOR, and AUC by ACR (TR4) and Kwak TI-RADS (4B) for malignancy risk stratification of thyroid nodules were 94.3% and 96.4%; 52.2% and 53.7%; 17.5185 and 31.8051; 0.786 and 0.884, respectively. There were no significant differences in diagnostic accuracy in any of the direction comparisons of the two systems; (4) Conclusions: ACR and Kwak TI-RADS had good diagnostic performances (AUCs > 85%). Although we determined the best cut-off values in individual risk stratification systems based on statistical assessment, clinicians can adjust the optimal cut-off value according to the clinical purpose of the ultrasonography because raising or lowering cut-points leads to reciprocal changes in sensitivity and specificity.

Effect of Decreasing the ACR TI-RADS Point Assignment for Punctate Echogenic Foci When They Occur in Mixed Solid and Cystic Thyroid Nodules

OBJECTIVE. Using the American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS), this study sought to determine whether decreasing the point assignment for punctate echogenic foci in mixed solid and cystic nodules would reduce the number of benign mixed solid and cystic nodules that were biopsied and would not substantially increase the number of missed mixed carcinomas MATERIALS AND METHODS. A multiinstitutional database of 3422 pathologically proven thyroid nodules was evaluated to identify all mixed solid and cystic nodules with punctate echogenic foci. We determined the numbers of mixed benign and malignant nodules that would receive ACR TI-RADS recommendations of fine-needle aspiration, follow-up, and no further evaluation if the points assigned to punctate echogenic foci were changed from 3 points to 1 or 2 points. RESULTS. A total of 287 mixed nodules were adequately characterized for evaluation. When the number of points assigned to punctate echogenic foci was changed from 3 points to 1 point, the point categories changed for 198 mixed nodules. Seven carcinomas would not undergo biopsy, but six of those seven would receive follow-up, and 44 benign nodules would not undergo biopsy. When 2 points were assigned to punctate echogenic foci, the point categories changed for 66 mixed nodules. Three carcinomas would not undergo biopsy, but all three of these would receive follow-up, and eight benign nodules would not undergo biopsy. CONCLUSION. Consideration should be given to decreasing the number of points assigned to punctate echogenic foci in mixed solid and cystic thyroid nodules, given the substantial decrease in the number of benign nodules requiring biopsy and the recommendation of follow-up for any carcinoma 1 cm or larger that did not undergo biopsy.

Thyroid Image Reporting and Data System Categorization: Effectiveness in Pediatric Thyroid Nodule Assessment

Ultrasonography (US) is the main imaging method to assess thyroid nodules. In the pediatric population, thyroid nodules are less prevalently seen than those in adults. However, approximately 25% of the nodules can be malignant. Validation of Thyroid Image Reporting and Data System (TI-RADS) classification has been mostly tested in adults, and information on pediatric cases is limited. In the current study, we aim to define the diagnostic power of the TI-RADS risk stratification method in pediatric thyroid nodules.The study population consists of 68 nodules of 64 patients (20 malignant, 48 benign). We have included patients at least 18 years and with a pathological diagnosis. The researchers evaluated the US images of the patients, if available. If US images cannot be found, US reports of the patients were evaluated to define TI-RADS points and category.Mean age of the population is 15.15 ± 2.66 years. There were 10 (17.7%) male patients and 58 (85.3%) female patients. Median nodule size was 8 mm. Final diagnosis was benign in 48 nodules (70.6%) and malignant in 20 nodules (29.4%). There were 5 follicular carcinoma cases and 15 papillary carcinoma cases. The area under the curve estimate was 0.89 (95% confidence interval, 0.80-0.98), and the area under the curve value confirmed the diagnostic efficacy of TI-RADS categorization in pediatric thyroid nodules. A TI-RADS category of 4 or 5 seemed to be a good cutoff point to predict malignancy.To conclude, TI-RADS categorization can be effectively used to assess pediatric thyroid nodules. Nodules with TI-RADS categories of 4 and 5 have the greatest risk of malignancy, and they should be evaluated pathologically.

American College of Radiology Thyroid Imaging Reporting and Data System standardises reporting of thyroid ultrasounds

Background

Thyroid nodules are common, the majority benign. The small risk of malignancy leads to excessive workup. Thyroid ultrasound is essential for risk stratification and management guidance. Without an organised reporting guideline, reports do not add significant value to referring clinicians. The American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) was developed to aid ultrasound reporting, lessen excessive biopsies and diagnose thyroid cancers.

Objectives

To standardise reporting of thyroid ultrasounds by utilising an organised reporting guideline based on ACR TI-RADS.

Method

Thyroid ultrasound reports generated by radiology registrars at an academic hospital were studied in two phases. In Phase 1, the reports were generated as free text, and in Phase 2, using a guideline based on ACR TI-RADS. The percentages of reports that described the maximum size, the five ACR TI-RADS features and a management recommendation were compared.

Results

A total of 130 reports were studied. Significant improvement was observed in the description of all five ACR TI-RADS categories (p < 0.0001) from Phase 1 to Phase 2. Of all the reports, 89% included a management recommendation. Reports including an ACR TI-RADS-based recommendation increased from 48% to 75% (p < 0.05). Recommendation for biopsy increased from 35.4% to 53.8% (p < 0.05).

Conclusion

Introduction of an organised reporting guideline based on ACR TI-RADS, standardised reporting of thyroid ultrasounds by increasing description of thyroid nodule features and ensuring appropriate management recommendations. This, in future, will prevent underdiagnosis of thyroid cancer and unnecessary workup of benign nodules.

Large (≥3cm) thyroid nodules with benign cytology: Can Thyroid Imaging Reporting and Data System (TIRADS) help predict false-negative cytology?

Background

There is controversy about the accuracy of the fine-needle aspiration (FNA) cytology results in large sized thyroid nodules. Our aim was to evaluate the false-negative rate of FNA for large thyroid nodules and the usefulness of the Thyroid Imaging Reporting and Data System (TIRADS) in predicting false-negative cytology for large thyroid nodules with benign cytology.

Methods

632 thyroid nodules larger than or equal to 3cm in size with subsequent benign cytology on US-guided FNA were included. US features of internal composition, echogenicity, margin, calcifications, and shape were evaluated, and nodules were classified according to TIRADS. TIRADS category 3 included nodules without any of the following suspicious features:solidity, hypoechogenicity or marked hypoechogenicity, microlobulated or irregular margins, microcalcifications, and taller-than-wide shape. Category 4a, 4b, 4c, and 5 were assigned to nodules showing one, two, three or four, or five suspicious US features, respectively. US features associated with malignancy for these lesions were analyzed and malignancy risk according to TIRADS was calculated.

Results

Of the 632 lesions, 23 lesions(3.6%) were malignant and 609(96.4%) were benign, suggesting a 3.6% false-negative rate for FNA cytology. Of the 23 malignant lesions, final pathology was mainly follicular carcinoma minimally invasive(65.2%, 15/23) and the follicular variant of papillary carcinoma(26.1%, 6/23). The malignancy risks of categories 3, 4a, 4b, and 4c nodules were 0.9%, 4.6%, 10.0%, and 11.8%, respectively.

Conclusion

Large thyroid nodules with benign cytology had a relatively high false-negative risk of 3.6% and TIRADS was helpful in predicting false-negative cytology for these lesions.

Hypermetabolic Thyroid Incidentaloma on Positron Emission Tomography: Review of Laboratory, Radiologic, and Pathologic Characteristics

Introduction

Incidental hypermetabolic thyroid lesions on Positron Emission Tomography have significant clinical value and may harbor malignancy. In this study we evaluated laboratory, radiologic, and pathologic characteristics of incidental hypermetabolic thyroid lesions.

Materials and Methods

We evaluated 18 patients prospectively with various malignancies and hypermetabolic thyroid incidentaloma. The thyroid function tests, ultrasound assessment, and guided FNA biopsy were performed on all cases.

Results

We included 9 male and 9 female patients with mean age of 51 years. Most common malignancy was colon cancer. Metabolic activity quantification using maximum standard uptake value demonstrated range between 1.4 and 65.4 with mean value of 9.4. We found highest metabolic activity in patients with lung adenocarcinoma, B-cell lymphoma, and colon adenocarcinoma. On ultrasound exam most thyroid lesions were of solid, hypoechoic, noncalcified nature with either normal or peripheral increased vascularity. FNA biopsy report was benign in 15 cases and malignant or highly suggestive for malignancy in 3 other cases. Two of the three malignant cases demonstrated metabolic activity higher than average SUV max.

Conclusion

Most thyroid hypermetabolic incidentalomas are benign lesions, while higher values of SUV max are in favor of malignancy. This mandates further evaluation of incidentally found thyroid hypermetabolic lesions on routine PET/CT scans.

Cytologically indeterminate thyroid nodules: increased diagnostic performance with combination of US TI-RADS and a new scoring system

To investigate the diagnostic performance of combination of ultrasound (US) thyroid imaging reporting and data system (TI-RADS) and a new US scoring system for diagnosing thyroid nodules (TNs) with indeterminate results (Bethesda categories III, IV and V) on fine-needle aspiration (FNA) cytology. 453 patients with 453 cytologically indeterminate TNs were included in this study. Multivariate analyses were performed to construct the scoring system. The diagnostic performances of TI-RADS and the combined method were evaluated and compared. Multivariate analyses revealed that marked hypoechogenicity, taller than wide shape and absence of halo sign were independent predictors for malignancy in cytologically indeterminate TNs. Scoring system was thereafter defined as follows: risk score (RS) = 3.2 x (if marked hypoechogenicity) + 2.8 x (if taller than wide shape) + 1.3 x (if absence of halo sign). Compared with TI-RADS alone, the areas under the receiver operating characteristic curves (AUC), specificity, accuracy and positive predictive value (PPV) of the combined method increased significantly with 0.731 versus 0.569, 48.5% versus 14.1%, 76.2% versus 62.3%, and 70.9% versus 59.9%, respectively (all P < 0.05). The combination of TI-RADS and new US scoring system showed superior diagnostic performances in predicting malignant TNs with indeterminate FNA cytology results in comparison with TI-RADS alone.