The use of modified TI-RADS using contrast-enhanced ultrasound features for classification purposes in the differential diagnosis of benign and malignant thyroid nodules: A prospective and multi-center study

Abstract

ObjectivesTo evaluate the diagnostic efficacy of a modified thyroid imaging reporting and data system (TI-RADS) in combination with contrast-enhanced ultrasound (CEUS) for differentiating between benign and malignant thyroid nodules and to assess inter-observer concordance between different observers.MethodsThis study included 3353 patients who underwent thyroid ultrasound (US) and CEUS in ten multi-centers between September 2018 and March 2020. Based on a modified TI-RADS classification using the CEUS enhancement pattern of thyroid lesions, ten radiologists analyzed all US and CEUS examinations independently and assigned a TI-RADS category to each thyroid nodule. Pathology was the reference standard for determining the diagnostic performance (accuracy (ACC), sensitivity (SEN), specificity (SPN), positive predictive value (PPV), and negative predictive value (NPV)) of the modified TI-RADS for predicting malignant thyroid nodules. The risk of malignancy was stratified for each TI-RADS category-based on the total number of benign and malignant lesions in that category. ROC curve was used to determine the cut-off value and the area under the curve (AUC). Cohen’s Kappa statistic was applied to assess the inter-observer agreement of each sonological feature and TI-RADS category for thyroid nodules.ResultsThe calculated malignancy risk in the modified TI-RADS categories 5, 4b, 4a, 3 and 2 nodules was 95.4%, 86.0%, 12.0%, 4.1% and 0%, respectively. The malignancy risk for the five categories was in agreement with the suggested malignancy risk. The ROC curve showed that the AUC under the ROC curve was 0.936, and the cutoff value of the modified TI-RADS classification was >TI-RADS 4a, whose SEN, ACC, PPV, NPV and SPN were 93.6%, 91.9%, 90.4%, 93.7% and 88.5% respectively. The Kappa value for taller than wide, microcalcification, marked hypoechoic, solid composition, irregular margins and enhancement pattern of CEUS was 0.94, 0.93, 0.75, 0.89, 0.86 and 0.81, respectively. There was also good agreement between the observers with regards to the modified TI-RADS classification, the Kappa value was 0.80.ConclusionsThe actual risk of malignancy according to the modified TI-RADS concurred with the suggested risk of malignancy. Inter-observer agreement for the modified TI-RADS category was good, thus suggesting that this classification was very suitable for clinical application.

Evaluation of Fine Needle Aspiration Cytology [Bethesda Classification] Versus Ultrasonography [Thyroid imaging recording and data system [TIRADS] Classification] in Diagnosis of Thyroid Nodule

“…From table [5] and using equations, the sensitivity of ultrasound and FNAC for diagnosis of malignant thyroid nodules were 57.1% and 87.5% respectively. However, both were 100% specific for detection of malignant nodules.…”

“…The size of the thyroid gland and assessment of thyroid nodules were conducted using the TIRADS, categorizing lesions into six classifications. Abdominal examinations included inspection and superficial palpation [5] .…”

Applying machine-learning models to differentiate benign and malignant thyroid nodules classified as C-TIRADS 4 based on 2D-ultrasound combined with five contrast-enhanced ultrasound key frames

“…For example, some Hashimoto’s nodules may show hypoechogenicity with blurred margins on 2D-US, which may be classified as TIRADS >4 and require unnecessary FNA according to the guidelines ( 7 , 40 , 41 ). CEUS, as a novel noninvasive microangiography technology, can reveal microvasculature with a smaller diameter (>40 µm) than that by CDFI (>100 µm) and is helpful in the detection of malignant thyroid nodules ( 42 , 43 ). Recent studies have indicated that CEUS could modify the current TIRADS to create a new risk stratification that may reduce unnecessary biopsies ( 42 – 46 ).…”

“…CEUS, as a novel noninvasive microangiography technology, can reveal microvasculature with a smaller diameter (>40 µm) than that by CDFI (>100 µm) and is helpful in the detection of malignant thyroid nodules (42,43). Recent studies have indicated that CEUS could modify the current TIRADS to create a new risk stratification that may reduce unnecessary biopsies (42)(43)(44)(45)(46). Our team had published one CEUS-TIRADS model to differentiate thyroid nodules (C-TIRADS 4) by combining CEUS with C-TIRADS (46), which had high clinical practicability in clinic.…”

Combining CEUS and ultrasound parameters in thyroid nodule and cancer diagnosis: a TIRADS-based evaluation

“…There were other proposals of CEUS + TIRADS approach, with slightly different designs but also with improved outcomes One study found that when used together in a predictive model, TIRADS and CEUS they performed better than either method alone (P <0.05), with an accuracy of 86.6% for the combined score ( 21 ). In another multicentric study on a large number of cases, the authors found au AUC for the modified TIRADS of 0.936, sensitivity 93.6%, specificity 88.5%, with Kappa for CEUS evaluation of 0.81, describing good interobserver variability ( 34 ). In our group, for the B-mode-only TIRADS, the percentage of cancers identified in score 3 is 17.28%, in score 4 it is 57.9% and 81.25% in score 5; for the TIRADS + CEUS, in score 3 we identified 1.9% cancers, in score 4 we identified 23.6% and in score 5 – 68%.…”