Predictive value of sonographic features in preoperative evaluation of malignant thyroid nodules in a multinodular goiter

International Expert Consensus on US Lexicon for Thyroid Nodules

Multiple US-based systems for risk stratification of thyroid nodules are in use worldwide. Unfortunately, the malignancy probability assigned to a nodule varies, and terms and definitions are not consistent, leading to confusion and making it challenging to compare study results and craft revisions. Consistent application of these systems is further hampered by interobserver variability in identifying the sonographic features on which they are founded. In 2018, an international multidisciplinary group of 19 physicians with expertise in thyroid sonography (termed the International Thyroid Nodule Ultrasound Working Group) was convened with the goal of developing an international system, tentatively called the International Thyroid Imaging Reporting and Data System, or I-TIRADS, in two phases: (phase I) creation of a lexicon and atlas of US descriptors of thyroid nodules and (phase II) development of a system that estimates the malignancy risk of a thyroid nodule. This article presents the methods and results of phase I. The purpose herein is to show what has been accomplished thus far, as well as generate interest in and support for this effort in the global thyroid community.

Predictors and a prediction model for positive fine needle aspiration biopsy in C-TIRADS 4 thyroid nodules

Objectives

To screen out the predictors and establish a prediction model of positive fine needle aspiration biopsy (FNAB) in the Chinese Guidelines for Malignant Risk Stratification of Thyroid Nodule Ultrasound (C-TIRADS) 4 thyroid nodules, and this nomogram can help clinicians evaluate the risk of positive FNAB and determine if FNAB is necessary.

Methods

We retrospectively analyzed data from 547 patients who had C-TIRADS 4 thyroid nodules and underwent fine-needle aspiration biopsy (FNAB) at the Second Affiliated Hospital of Chongqing Medical University between November 30, 2021 and September 5, 2022. Patients who met our inclusion criteria were divided into two groups based on positive or negative FNAB results. We compared their ultrasound (US) features, BRAF V600E status, thyroid function, and other general characteristics using univariate and multivariate logistic regression analyses to identify independent predictors. These predictors were then used to construct a nomogram. The calibration plot, area under the curve (AUC), and decision curve analysis were employed to evaluate the calibration, discrimination, and clinical utility of the prediction model.

Results

Out of 547 patients, 39.3% (215/547) had a positive result on fine-needle aspiration biopsy (FNAB), while 60.7% (332/547) had a negative result. Univariate logistic regression analysis revealed no significant differences in TPOAb, TgAb, TSH, Tg, nodule location, sex, or solid status between the two groups (P>0.05). However, age, nodule size, internal or surrounding blood flow signal, microcalcifications, aspect ratio, morphology, and low echo showed significant differences (P<0.05). Multivariate logistic regression analysis was conducted to explore the correlation between potential independent predictors. The results showed that only age (OR=0.444, 95% Cl=0.296~0.666, P<0.001), low echo (OR=3.549, 95% Cl=2.319~5.432, P<0.001), microcalcifications (OR=2.531, 95% Cl=1.661~3.856, P<0.001), aspect ratio (OR=3.032, 95% Cl=1.819~5.052, P<0.001), and morphology (OR=2.437, 95% Cl=1.586~3.745, P<0.001) were independent predictors for a positive FNAB. These variables were used to construct a prediction nomogram. An ROC curve analysis was performed to assess the accuracy of the nomogram, and AUC=0.793, which indicated good discrimination and decision curve analysis demonstrated clinical significance within a threshold range of 14% to 91%.

Conclusion

In conclusion, 5 independent predictors of positive FNAB, including age (≤45 years old), low echo (yes), microcalcifications (yes), aspect ratio (>1) and morphology (irregular), were identified. A nomogram was established based on the above 5 predictors, and the nomogram can be used as a complementary basis to help clinicians make decisions on FNAB of C-TI-RADS 4 thyroid nodules.

Role of echogenic foci in ultrasonographic risk stratification of thyroid nodules: Echogenic focus scoring in the American College of Radiology Thyroid Imaging Reporting and Data System

Background

Although echogenic foci may raise malignancy rates in thyroid nodules, the association between peripheral calcification or macrocalcification and thyroid carcinoma is controversial. We evaluated the malignancy probability of various echogenic foci and explored whether the method of determining a thyroid nodule’s point score in the echogenic focus category of the American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS) is reasonable.

Methods

We retrospectively evaluated 819 patients with 852 nodules. The patterns of echogenic foci on ultrasonography were classified into the following four categories: punctate echogenic foci, macrocalcification, peripheral calcification, and multiple different types of echogenic foci. The core needle biopsy results were divided into two groups: benign and malignant or suspicious for malignancy.

Results

Among the 852 nodules, 471 (55.3%) had echogenic foci on ultrasonography. Of these nodules, there was no significant statistical difference in the malignant or suspicious for malignancy rate between nodules with peripheral calcification and those with macrocalcification [40.0% (8/20) vs. 30.6% (11/36), respectively; p = 0.474]. The incidence of malignancy or suspicious for malignancy for nodules with peripheral calcification, macrocalcification, or multiple different types of echogenic foci was significantly lower than the incidence for punctate echogenic foci alone, with odds ratios of 0.265 [95% confidence interval (CI): 0.105–0.667; p = 0.005], 0.175 (95% CI: 0.083–0.368; p = 0.000), and 0.256 (95% CI: 0.136–0.482; p = 0.000), respectively.

Conclusion

We found no significant statistical difference in the risk of malignancy or suspicious for malignancy rate between peripheral calcification and macrocalcification in thyroid nodules. We observed that nodules with multiple different types of echogenic foci were not associated with higher malignant or suspicious for malignancy rates compared with nodules with punctate echogenic foci alone.

Malignancy risk of thyroid nodules with minimally cystic changes: a multicenter retrospective study

Purpose

The aim of this multicenter study was to investigate the malignancy risk of minimally cystic thyroid nodules (MCTNs) using cyto-histopathologic diagnoses as the reference standard.

Methods

From June 2015 to September 2015, 5,601 thyroid nodules (≥1 cm) from 4,989 consecutive patients who underwent thyroid ultrasonography (US) at 26 institutions were retrospectively analyzed. Each thyroid nodule was categorized according to its cystic proportion: purely solid, minimally cystic (≤10%), and partially cystic (>10%). The malignancy risk of MCTNs was compared with those of purely solid nodules and partially cystic thyroid nodules (PCTNs). The malignancy risk of MCTNs was assessed according to echogenicity and the presence of suspicious US features.

Results

The prevalence of MCTNs was 22.5%. The overall malignancy risk of MCTNs was 8.8%, which was significantly lower than that of purely solid nodules (29.5%) (P<0.001), and slightly higher than that of PCTNs (6.2%) (P=0.013). The risk of malignancy associated with MCTNs was similar to that of PCTNs regardless of echogenicity or the presence of suspicious US features (all P>0.05). MCTNs were associated with a higher risk of malignancy in hypoechoic nodules than in isohyperechoic nodules and in nodules with suspicious US features than in those without suspicious US features (all P<0.001).

Conclusion

The malignancy risk of MCTNs was significantly lower than that of purely solid nodules. MCTNs could be categorized as PCTNs rather than as solid nodules to increase the accuracy of the risk stratification system for thyroid nodules.

Revision Thyroid Surgery

The incidence of recurrence in well-differentiated thyroid malignancies range from 10 to 30%. It is estimated that about 31-46% of patients with differentiated thyroid cancer will have the persistent disease and 1.2-6.8% will have structural recurrences during post-operative monitoring, depending on the initial therapy and prognostic variables. It is challenging to decide on treatment versus active monitoring following repeated or persistent tumour detection. The biological factors of the tumour and the patient guide us in the overall decision-making. Revision thyroid surgery is technically challenging. The morbidity encountered during the revision surgery is related to the anatomy of the region undergoing dissection, the degree of fibrosis and scarring from prior surgery and the operating surgeon's experience. Successful comprehensive management of revision thyroid surgery needs a multi-disciplinary approach. This review article highlights the definition, indications for revision surgery, identification of recurrent disease, management of parathyroid and recurrent laryngeal nerves with neuromonitoring.

Preoperative ultrasound characteristics in determining the likelihood of cytologically confirmed (Bethesda VI), 1-4 cm papillary thyroid tumours requiring completion thyroidectomy

BACKGROUND

Papillary thyroid carcinoma (PTC) is the most commonly diagnosed differentiated thyroid carcinoma. There is controversy about performing upfront lobectomy vs thyroidectomy for smaller well differentiated thyroid carcinoma.

METHODS

A retrospective study from 2015 to 2020 was conducted consisting of consecutive patients with a preoperative malignant (Bethesda VI) cytology on fine needle aspirate (FNA) consistent with PTC. Specific ultrasonographic features such as taller than wide, hypoechogenicity, irregular margins, internal vascularity and microcalcifications were recorded. Criteria for exclusion was the presence of positive lymph nodes, extrathyroidal extension, familial thyroid carcinoma and bilateral disease detected preoperatively. Outcome was defined as a lobectomy being adequate treatment or a completion thyroidectomy recommended based on current 2015 ATA guidelines.

RESULTS

Preoperative malignant cytological nodules (Bethesda VI) with irregular margins on sonography were significantly (p = 0.025) at increased risk (OR = 2.48) of requiring a completion thyroidectomy. There was also no statistically significant difference between groups when stratified by size with 50% of tumours between 1 and 2 cm requiring a completion thyroidectomy.

CONCLUSIONS

The presence of irregular margins on ultrasound predicts an increased risk of requiring a completion thyroidectomy. Specific consideration of this sonographic finding should be made when counselling patients who have cytologically confirmed papillary thyroid carcinoma regarding the best choice of thyroid operation.

Diagnostic Value of Sonographic Features in Distinguishing Malignant Partially Cystic Thyroid Nodules: A Systematic Review and Meta-Analysis

Ultrasonography (US) is one of the most important methods for the management of thyroid nodules, which can be classified as solid, partially cystic, or cystic by composition. The various Thyroid Imaging Reporting and Data System classifications pay more attention to solid nodules and have reported pertinent US features associated with malignancy. However, the likelihood of malignancy of partially cystic thyroid nodules (PCTNs) is 3.3-17.6%, and few studies have systematically discussed the value of US in differentiating such entities. Therefore, we deemed it necessary to perform a systematic evaluation of US features in recognizing malignant PCTNs. Our systematic review and meta-analysis aimed to assess the value of US features in predicting malignant PCTNs. We searched the PubMed/MEDLINE, Web of Science, and Cochrane Library databases to find studies that researched US features of PCTNs and that were published before June 2020. Review Manager 5.3 was used to summarize suspicious US features and calculate the sensitivity, specificity, and likelihood ratios. MetaDiSc 1.4 was used to estimate receiver operating characteristic curves and calculate areas under the curves (AUCs). Our review included eight studies with a total of 2,004 PCTNs. Seven features were considered to be associated with malignancy. High specificity (>0.9) was found in nodules with a taller-than-wide shape, those that were spiculated/microlobulated or with an ill-defined margin, those with microcalcification, and a non-smooth rim. Among US features, eccentric configuration, microcalcification, and marked or mild hypoechogenicity were more reliable in predicting malignancy (AUC: 0.9592, 0.8504, and 0.8092, respectively). After meta-analysis, we recommend combining PCTN US features including an eccentric internal solid portion, marked or mild hypoechogenicity, and presence of microcalcification to better identify malignant nodules. More studies are needed to explore and improve the diagnostic value of US in PCTNs.

EU-TIRADS-Based Omission of Fine-Needle Aspiration and Cytology from Thyroid Nodules Overlooks a Substantial Number of Follicular Thyroid Cancers

BACKGROUND

The classification of nodules by Thyroid Imaging Reporting and Data Systems (TIRADS) is important in guiding management. Whether sensitivity in identifying thyroid cancers varies with thyroid cancer phenotype remains unclarified.

METHODS

The ultrasound (US) characteristics of nodules of 26,908 nodular goiter patients were recorded. Fine-needle aspiration cytology (FNA) was performed in all nodules >1 cm irrespective of US findings (n = 25,025) and in nodules between 5 mm and 10 mm with suspicious US characteristics (n = 1,883). Of the 3281 operated cases, 221, 30, and 23 were papillary (PTC), follicular (FTC), and medullary (MTC) cancers, respectively. The US-based indication of FNA, as defined by EU-TIRADS scores, combined with lesion size, was calculated. This study design is unique in avoiding the common selection bias when TIRADS' sensitivity is tested in a cohort selected for FNA and surgery based on the same US characteristics on which TIRADS is based.

RESULTS

The EU-TIRADS score influences decision of FNA in the 10-20 mm range. In such nodules (n = 118), the number of suspicious features (marked hypoechogenicity, microcalcifications, irregular shape, and irregular border) per lesion was lower in FTC (0.7 ± 0.6) than in PTC (1.7 ± 1.0) or MTC (1.8 ± 0.7; p < 0.02), resulting in EU-TIRADS scores of 4.1 ± 0.6, 4.8 ± 0.3, and 4.9 ± 0.2, respectively (p < 0.01). The EU-TIRADS-based FNA indication rate was lower in FTC (55.5%) compared to PTC (85.0%) and MTC (88.9%) (p=0.02).

CONCLUSIONS

EU-TIRADS-defined suspicious US features are less common in FTC than in PTC and MTC. Therefore, a substantial number of FTCs in the 10-20 mm range escape surgery.

The diagnostic value of ultrasonography in detection of different types of thyroid nodules

Background

This article discusses the importance of high frequency ultrasonography in detection of different types of thyroid nodules considering only the histopathological examination of the surgical specimens as the final diagnosis. We studied 50 patients referred to ENT clinic with a thyroid nodule. Ultrasonography and ultrasound-guided fine-needle aspiration biopsy were done to all the patients. Thyroid surgery was done according to FNAB results.

Result

From 50 thyroid specimens, the US could predict the malignancy in 18 specimens. By histopathology, only 16 specimens were malignant, and 34 were benign thyroid disease. The sensitivity, specificity, and accuracy of US were 100%, 94.12%, and 96% respectively. The most suspicious ultrasongraphic feature was microcalcification followed by taller than wider (T ˃ W).

Conclusion

High frequency ultrasound is a very important tool to predict the malignant possibility during thyroid nodule evaluation.

The American Association of Endocrine Surgeons Guidelines for the Definitive Surgical Management of Thyroid Disease in Adults

OBJECTIVE

To develop evidence-based recommendations for safe, effective, and appropriate thyroidectomy.

BACKGROUND

Surgical management of thyroid disease has evolved considerably over several decades leading to variability in rendered care. Over 100,000 thyroid operations are performed annually in the US.

METHODS

The medical literature from 1/1/1985 to 11/9/2018 was reviewed by a panel of 19 experts in thyroid disorders representing multiple disciplines. The authors used the best available evidence to construct surgical management recommendations. Levels of evidence were determined using the American College of Physicians grading system, and management recommendations were discussed to consensus. Members of the American Association of Endocrine Surgeons reviewed and commented on preliminary drafts of the content.

RESULTS

These clinical guidelines analyze the indications for thyroidectomy as well as its definitions, technique, morbidity, and outcomes. Specific topics include Pathogenesis and Epidemiology, Initial Evaluation, Imaging, Fine Needle Aspiration Biopsy Diagnosis, Molecular Testing, Indications, Extent and Outcomes of Surgery, Preoperative Care, Initial Thyroidectomy, Perioperative Tissue Diagnosis, Nodal Dissection, Concurrent Parathyroidectomy, Hyperthyroid Conditions, Goiter, Adjuncts and Approaches to Thyroidectomy, Laryngology, Familial Thyroid Cancer, Postoperative Care and Complications, Cancer Management, and Reoperation.

CONCLUSIONS

Evidence-based guidelines were created to assist clinicians in the optimal surgical management of thyroid disease.

Investigating the Effect of Thyroid Nodule Location on the Risk of Thyroid Cancer

Background: Thyroid nodules are routinely evaluated with ultrasound. Our aim was to determine if thyroid nodule location was a useful feature to predict thyroid cancer. Materials and Methods: Retrospective review of patients with thyroid nodules from six referral centers from 2006 to 2010. A total of 3313 adult patients with thyroid nodules and confirmed benign or malignant thyroid diagnoses were included. Results: Mean patient age was 54.2 (18-97) years, and the majority were women (n = 2635, 79.8%). A total of 3241 nodules were analyzed, 335 (10.3%) of which were malignant. Thyroid nodule location was an independent risk factor in predicting thyroid cancer (p = 0.005). Thyroid cancer odds were highest in the isthmus (odds ratio [OR] = 2.4, 95% confidence interval [CI] 1.6-3.6, p < 0.0001). In a multivariate regression model adjusting for age, sex, family history of thyroid cancer, radiation exposure, nodule size, and American College of Radiology (ACR) TI-RADS (Thyroid Imaging Reporting and Data System) score, the isthmus nodules had the highest risk of malignancy (OR = 2.4 [CI 1.5-3.9], p = 0.0007), followed by upper thyroid nodules (OR = 1.8 [CI 1.2-2.7], p = 0.005) and then middle thyroid nodules (OR = 1.5 [CI 1.1-2.0], p = 0.01) compared with lower thyroid nodules. Isthmus nodules were significantly smaller in size compared with middle (p < 0.0001) and lower (p = 0.0004), but not upper nodules (p = 0.25), with a mean size of 15.5 mm (±10.7). Conclusions: Thyroid nodule location is an independent risk factor in predicting the risk of thyroid cancer. Isthmic nodules carry the highest risk of cancer diagnosis and lower lobe nodules carry the lowest risk.

A novel computerised quantification of thyroid vascularity in the differentiation of malignant and benign thyroid nodules

PURPOSE

Only five percent of thyroid nodules are malignant. It is important to find reliable and at the same time non-invasive methods to identify high-risk nodules. The aim of this study was to determine the diagnostic validity of a morphologic feature-oriented approach of ultrasound study for the identification of malignant thyroid nodules.

MATERIAL AND METHODS

Seventy-one thyroid nodules in 71 consecutive patients were evaluated with both ultrasonography (US) and US-assisted fine needle aspiration biopsy (FNAB). Thyroid grey-scale and power Doppler US were performed, and a Windows-based software was designed to process power Doppler US (PDUS) images that were recorded directly by the US device. We provided a histogram graph of coloured pixels and calculated the Malignancy Index to identify the probability of malignancy for each thyroid nodule.

RESULTS

Thirty-six nodules (50.7%) were determined to be malignant in FNAB. Area under the receiver operating curve was 0.91 (95% CI: 0.85-0.98) for PDUS-based malignancy index in differentiating malignant thyroid nodules from benign ones. The best cut-off point for malignancy index was determined to be 0.092, with a sensitivity of 86.1% and specificity of 80% in identifying malignant nodules.

CONCLUSIONS

This PDUS-driven malignancy index using a contour-finding algorithm approach could accurately and reliably differentiate malignant and benign thyroid nodules. As a pre-FNAB assessment, the malignancy index may be able to reduce the number of patients with nodular thyroid disease undergoing this invasive procedure.

Nodules with nonspecific ultrasound pattern according to the 2015 American Thyroid Association malignancy risk stratification system: A comparison to the Thyroid Imaging Reporting and Data System (TIRADS-Na)

New sonographic patterns have been recommended by the 2015 American Thyroid Association (ATA) to stratify nodules in terms of malignancy risk and help guide biopsy decision. This study aimed to compare the ultrasound part of the ATA guidelines and the Thyroid Imaging Reporting and Data System (TIRADS-Na).In 2013 to 2016, 708 thyroid nodules in 505 patients were confirmed by postoperative histopathology. Hypoechogenicity, solidity, microcalcification, irregular margin, and a taller-than-wide shape were considered features suggesting malignancy. Sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) were obtained for the TIRADS and ATA guidelines.Of the 708 nodules, 341(48.2%) and 367(51.8%) were benign and malignant, respectively. Based on the ultrasound 2015 ATA guidelines, 62 nodules had nonspecific pattern (both malignant and benign features); malignancy rates of nodules with very low, low, intermediate, and high suspicion, and nonspecific pattern were 0, 17.7%, 57.9%, 90.0%, and 69.4%, respectively (P < .001). Malignancy rates of categories 2/3/4/5 nodules by TIRADS were 0, 8.1%, 67.0%, and 90.1%, respectively (P < .001). Based on pathological results, the AUC, sensitivity, specificity, NPV, and PPV were 0.926, 96.7%, 81.5%, 84.9%, and 95.9% for TIRADS, and 0.920, 93.5%, 82.4%, 85.1%, and 92.1% for ATA patterns, respectively. The TIRADS was generally more efficient than the 2015 ATA guidelines, especially for nodules >2 cm in diameter or those with nonspecific pattern.The TIRADS show a relative superiority over the ultrasound 2015 ATA guidelines, especially for nodules with >2 cm diameter or nonspecific pattern.

Prospective analysis of inter-observer and intra-observer variability in multi ultrasound descriptor assessment of thyroid nodules

Aim: The aim of this study was to evaluate the inter- and intra-observer variability and accuracy of ultrasound assessment of thyroid nodules using a descriptive lexicon. Materials and methods: A prospective study was performed on complete ultrasound examinations, including sonoelastography and color Doppler ultrasound of 18 patients with 20 thyroid nodules. A total of 20 records of thyroid nodules from these techniques were duplicated, numbered, and randomly arranged. Five radiologists assessed the recordings independently. Cohen Kappa and Fleiss Kappa statistics were used to determine the degree of intra- and inter-observer agreement. Results: Mean accuracy rates for all radiologists, for all ultrasound features, ranged from 82.7 to 87.8%. For B-mode and strain elastography, accuracies ranged from 65.0 to 100% and 47.4 to 86.8%, respectively. Concerning intra-observer variability, three radiologists demonstrated almost perfect agreement (the κ-value ranged from 0.81 to 0.86), and a substantial agreement was noted for the two remaining radiologists. The κ-values for inter-observer agreement ranged from 0.61 for macrocalcifications (substantial agreement) to 0.33 for Asteria four-point elastography scale criteria (fair agreement). Conclusions: The results suggest relatively good inter-observer and excellent intra-observer agreement in the assessment of thyroid nodules using ultrasound, and fair agreement in the case of strain elastography.

The Efficacy and The Safety of Ultrasound-guided Ablation Therapy for Treating Papillary Thyroid Microcarcinoma

The prevalence of papillary thyroid microcarcinoma (PTMC) increases rapidly all around the world, but the management of PTMC hasn't reached a consensus. Recently, ultrasound-guided (US-guided) ablation therapy was introduced as a feasible treatment for low-risk PTMC. The clinical application of US-guided ablation therapy needs doctors' effort to investigate the efficacy and the safety of US-guided ablation in treating PTMC carefully. Although the present evidence showed some limitations, such as short-term study time spans and no randomized control design, in our perspective, US-guided thermal ablation therapy has good short-term efficacy and safety and is a promising PTMC's treatment in future clinical practice.

Thyroid disease in the perimenopause and postmenopause period

The interpretation of thyroid function tests should be cautiously made during the perimenopause and postmenopause period bearing in mind that physiologic changes do exist in this group of women in terms of secretion and metabolism of thyrotropin and thyroid hormones. Moreover the incidence of thyroid disorders increases in postmenopausal and elderly women. There is no consensus for screening postmenopausal women even though there is well-known evidence about the effect of thyroid status on cognitive function, cardiovascular risk, bone turnover, and longevity. The diagnosis of any thyroid disorder is challenging in these patients because the symptoms are more subtle and attributed to menopausal symptoms. Management requires more attention in this population than that of younger groups, because high doses of L-thyroxine can lead to cardiac complications and increased bone turnover. Furthermore radio-iodine is preferred in treatment of hyperthyroidism in older patients. The risk of nodular thyroid disease and thyroid cancers increases in this group. Although the diagnostic approach is the same as for young patients, the risk of surgery is high and disease prognosis is worse. Women with any form of thyroid disease should be treated according to the current guidelines. Decision for menopausal hormonal therapy should be individualized regardless of the concomitant presence of thyroid disorders.

Evaluation of the thyroid nodule with high-resolution ultrasonography and elastography without fine needle aspiration biopsy

INTRODUCTION

Fine needle aspiration biopsy (FNAB) is the gold standard screening technique used in the diagnostic protocol for thyroid nodules. However, it is not free of complications.

OBJECTIVE

To identify thyroid nodules in which FNAB could be avoided during the diagnostic process by means of the use of a high-resolution ultrasonography or elastography.

MATERIAL AND METHOD

A prospective, non-randomized study was carried out. Single thyroid nodules and dominant nodules of multinodular goiter were included. Patients who had undergone thyroid surgery in the past were excluded. All patients underwent a high-resolution ultrasound and elastography, and, subsequently, a FNAB. We analyzed the ultrasound variables in 2D and Doppler, followed by the elastographic variables, and the results of the FNAB according to Bethesda. To correlate the data, the nodules were classified as benign or malignant. Student's t test, the Chi-square test and a logistic regression analysis were applied for the statistical analysis.

RESULTS

A total of 221 thyroid nodules were analyzed, 32 of which were malignant (14%). The most predictive ultrasound findings of malignancy (P<.05) were a hypoechoic or complex echostructure (OR=11.832), the presence of microcalcifications (OR=9.637) and chaotic vascularization observed in the Doppler (OR=46.464). With regard to the elastography, elastographic patterns i and ii were seen to be associated with benignity (P=.0004 and P<.0001, respectively). When type i or ii elastography was combined with an ultrasound showing a non-hypoechoic nor complex echostructure, without microcalcifications nor chaotic vascularization in the Doppler ultrasound, 100% of the cases were benign with a specificity of 100% and a sensitivity of 14%.

CONCLUSIONS

The combination of a high-resolution ultrasound with an elastography makes it possible to select cases where a FNAB does not have to be performed. Cases susceptible to a periodic follow-up without the use of a FNAB are those without a hypoechoic nor complex structure, no microcalcifications, non-chaotic vascularization and a type i or ii elastography.

Combination of Maximum Shear Wave Elasticity Modulus and TIRADS Improves the Diagnostic Specificity in Characterizing Thyroid Nodules: A Retrospective Study

OBJECTIVES

The present study is aimed at evaluating the diagnostic value of combining shear wave elastography (SWE) parameters and the thyroid imaging reporting and data system (TIRADS) for differentiating between benign and malignant thyroid nodules.

METHODS

Patients who underwent conventional ultrasonography (US) and SWE before surgery were enrolled in the current study. Each nodule was given a TIRADS risk score. The effectiveness of the SWE parameters was assessed by odds ratios (ORs). The SWE scoring risk stratification was proposed beyond 95% probability, and the desired values were obtained according to the log-normal distribution. The area under the receiver-operating characteristic (AUC) was used to compare the diagnostic performance between TIRADS-alone and TIRADS + SWE.

RESULTS

A total of 262 patients with 298 thyroid nodules were enrolled in our study. The pathological analyses were conducted on 121 benign and 177 malignant nodules. The AUC values for TIRADS-alone and TIRADS + SWE were 0.896 (accuracy 83.2%) and 0.917 (accuracy 84.2%), respectively. However, the TIRADS + SWE scores showed a higher specificity (88.4%) and positive predictive value (91.2%) as compared with the TIRADS-alone of 73.6% and 83.2%, respectively.

CONCLUSIONS

Combining SWE and TIRADS improves the specificity of TIRADS-alone in differentiating between benign and malignant thyroid nodules.

Validation of American Thyroid Association Ultrasound Risk Assessment of Thyroid Nodules Selected for Ultrasound Fine-Needle Aspiration

OBJECTIVE

The aim of this study was to validate the American Thyroid Association (ATA) sonographic risk assessment of thyroid nodules.

METHODS

The ATA sonographic risk assessment was prospectively applied to 206 thyroid nodules selected for ultrasound-guided fine-needle aspiration (US-FNA), and analyzed with The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC), as well as surgical pathology for the subset undergoing surgical excision.

RESULTS

The analysis included 206 thyroid nodules averaging 2.4 cm (range 1-7 cm; standard error of the mean 0.07). Using the ATA US pattern risk assessment, nodules were classified as high (4%), intermediate (31%), low (38%), and very low (26%) risk of malignancy. Nodule size was inversely correlated with sonographic risk assessment, as lower risk nodules were larger on average (p < 0.0001). Malignancy rates determined by cytology/surgical pathology were high 100%, intermediate 11%, low 8%, and very low 2%, which were closely aligned with ATA malignancy risk estimates (high 70-90%, intermediate 10-20%, low 5-10%, and very low 3%). ATA US pattern risk assessment also appropriately predicted the proportion of nodules classified as malignant or suspicious for malignancy through TBSRTC classification-high (77%), intermediate (6%), low (1%), and very low 0%-as well as benign TBSRTC classification-high (0%), intermediate (47%), low (61%), and very low (70%) (p < 0.0001). Malignancy rates of surgically excised, cytologically indeterminate nodules followed ATA sonographic risk stratification (high 100%, intermediate 21%, low 17%, and very low 12%; p = 0.003).

CONCLUSION

This prospective study supports the new ATA sonographic pattern risk assessment for selection of thyroid nodules for US-FNA based upon TBSRTC and surgical pathology results. In the setting of indeterminate cytopathology, nodules categorized as atypia of undetermined significance/follicular lesion of undetermined significance with ATA high-risk sonographic patterns have a high likelihood of being malignant.

2016 Russian clinical practice guidelines for differentiated thyroid cancer diagnosis and treatment

В представленных клинических рекомендациях обсуждаются современные подходы к диагностике и лечению дифференцированного рака щитовидной железы у взрослых. Изменения в настоящей редакции Клинических рекомендаций касаются показаний к пункционной биопсии, скринингового определения концентрации кальцитонина, унификации заключений цитологического исследования, новых подходах к послеоперационной динамической стратификации риска рецидива, показаний к супрессивной и заместительной терапии, таргетной терапии йоднегативных форм дифференцированного рака щитовидной железы.

The utility of thyroid ultrasonography in the management of thyroid nodules

BACKGROUND

Ultrasonography for thyroid nodules is one of the most common imaging tests performed in the general population. Details from ultrasound reports guide biopsies and surgery. This study quantifies the completeness of these reports based on Thyroid Imaging and Reporting System (TI-RADS) criteria and considers their utility in predicting malignant disease.

METHODS

We retrospectively reviewed ultrasound reports for 329 thyroidectomy patients and extracted data elements using the TI-RADS criteria: nodule size, echogenicity, margins, vascularity, solid/cystic composition and the presence or absence of microcalcifications and the halo sign. We assessed the reports to determine whether individual or multiple criteria were associated with malignancy.

RESULTS

More than 97% of reports document nodule size; however, more than 90% of the reports noted only 3 or fewer of the 6 remaining TI-RADS criteria. The presence of microcalcifications was the most sensitive marker of malignancy (> 90%), whereas the documentation of irregular margins was the most specific indicator of malignancy (88%). Overall it was clear that microcalcifications, hypoechogenicity, irregular margins and solid nodules were significantly more likely to be found in malignant neoplasms; their absence predicted benign disease. Because so few reports consistently documented all criteria, the overall ability of thyroid ultrasonography to discriminate between lowerand higher-risk nodules is limited.

CONCLUSION

Although the accuracy of thyroid ultrasonography is good, few ultrasound reports contain the necessary information, as defined by TI-RADS, to predict malignancy and guide management. When reported, microcalcifications and/or irregular margins are the best predictors of malignancy.

Evaluation of Diagnostic Efficiency of Ultrasound Features on Malignant Thyroid Nodules in Chinese Patients

Background:

The aim of this study was to evaluate the efficacy of ultrasonic features in predicting the malignancy of thyroid nodules in a group of Chinese patients.

Methods:

In all, 762 patients with thyroid nodules (424 malignant and 338 benign) underwent ultrasound (US) check and surgery between March 2011 and July 2014 at Peking University First Hospital were identified. Univariate and receiver operating characteristic (ROC) analyses were performed to calculate the sensitivity, specificity, negative and positive predictive values of each US feature, and the accuracy of their combinations for prediction of malignancy.

Results:

Patients with malignant nodules were younger and without obvious risk history than those in the benign group (P < 0.001, P = 0.93). No individual US sign was fully predictive of a malignant lesion. The Youden indexes of irregular margins and hypoechogenicity were the first and second highest in all US features, which were 51.9% and 45.2%, respectively. The sensitivity of solid components (89.7%) and hypoechogenicity (89.2%) and the specificity of taller-than-wide shape (98.5%) and microcalcifications (90.6%) were the first and second highest in all US features. Intranodular flow on a color Doppler examination was a weak predictor of malignancy. Under ROC analysis excepting intranodular flow, the 95% confidence interval (CI) of areas under the curves of hypoechogenicity and irregular margins with any one of the US features were overlapped that of five-feature combinations (95% CI: 0.850–0.901).

Conclusions:

We should be alert with taller-than-wide shape and microcalcifications. Intranodular flow was a weak predictor of malignancy. According to Youden indexes and ROC analysis, irregular margins and hypoechogenicity combined with solid component or taller-than-wide shapes or microcalcifications have a high predicative value for malignant thyroid nodules in Chinese patients.

Diagnostic Performance of Shear Wave Elastography Parameters Alone and in Combination with Conventional B-Mode Ultrasound Parameters for the Characterization of Thyroid Nodules: A Prospective, Dual-Center Study

The aims of our study were to determine whether shear wave elastography (SWE) can improve the conventional B-mode differentiation of thyroid lesions, determine the most accurate SWE parameter for differentiation and assess the influence of microcalcifications and chronic autoimmune thyroiditis on SWE values. We examined 119 patients with 169 thyroid nodules who prospectively underwent B-mode ultrasound and SWE using the same ultrasound machine. The parameters assessed using SWE were: mean elasticity within the entire lesion (SWE-whole) and mean (SWE-mean) and maximum (SWE-max) elasticity for a 2-mm-diameter region of interest in the stiffest portion of the lesion, excluding microcalcifications. The discriminant powers of a generalized estimating equation model including B-mode parameters only and a generalized estimation equation model including both B-mode and SWE parameters were assessed and compared using the area under the receiver operating characteristic curve, in association with pathologic verification. In total, 50 and 119 malignant and benign lesions were detected. In generalized estimated equation regression, the B-mode parameters associated with higher odds ratios (ORs) for malignant lesions were microcalcifications (OR = 4.3), hypo-echogenicity (OR = 3.13) and irregular margins (OR = 10.82). SWE-max was the only SWE independent parameter in differentiating between malignant and benign tumors (OR = 2.95). The area under the curve for the B-mode model was 0.85, whereas that for the model combining B-mode and SWE parameters was 0.87. There was no significant difference in mean SWE values between patients with and without chronic autoimmune thyroiditis. The results of the present study suggest that SWE is a valuable tool for the characterization of thyroid nodules, with SWE-max being a significant parameter in differentiating benign and malignant lesions, independent of conventional B-mode parameters. The combination of SWE parameters and conventional B-mode parameters does not significantly improve the diagnosis of malignant thyroid nodules. The presence of microcalcifications can influence the SWE-whole value, whereas the presence of chronic autoimmune thyroiditis may not.

Why Thyroid Surgeons Are Frustrated with Radiologists: Lessons Learned from Pre- and Postoperative US

Optimal treatment of thyroid cancer is highly dependent on accurate staging of the extent of disease at presentation. Preoperative ultrasonography (US) is the most sensitive method for detecting metastatic lymph nodes and is recommended as part of the standard preoperative workup. Missed findings on preoperative scans may lead to understaging and inadequate surgical management, which subsequently predispose these patients to residual disease postoperatively and a higher risk for recurrence, possibly requiring repeat surgery. Traditionally, thyroid US for pre- and postoperative staging has been performed by radiologists. However, there is a growing trend away from radiologist-performed US in favor of surgeon-performed US. Recent surgical and endocrinology literature has shown that, when compared with surgeon-performed US, radiologist-performed preoperative staging US is less accurate and is inadequate for presurgical planning, with higher local recurrence rates. This review highlights the importance of accurate preoperative US for patients with differentiated thyroid cancer, with specific attention to deficiencies that exist in general radiology department thyroid US reports. We present a standardized approach to neck US reporting that incorporates the newly updated 2015 recommendations from the American Thyroid Association and also addresses the pertinent questions for thyroid surgeons. By ensuring comprehensive preoperative assessment and improving thyroid US reporting, we seek to improve patient access to optimized care. ^©RSNA, 2016.

[Clinical importance of thyroid gland cytology]

The cytological evaluation of fine needle biopsies (FNB) of the thyroid gland crucially depends on a close cooperation between clinicians and cytopathologists. Scintigraphy, sonography as well as clinical data and patient history are necessary for a correct interpretation of the indications for FNB; moreover, these data are of outstanding importance for cytopathologists for the correct interpretation of the cytomorphological findings. This overview describes the present standards in the acquisition, technical workup and cytopathological interpretation of thyroid gland tissue obtained by FNB, particularly focusing on the rapidly growing relevance of additional molecular pathological investigations to increase the diagnostic accuracy of thyroid FNB.

Pediatric thyroid nodules: ultrasonographic characteristics and inter-observer variability in prediction of malignancy

BACKGROUND

Pediatric thyroid nodules, while uncommon, have high malignancy risk. The objectives of the study were (1) to identify sonographic features predictive of malignancy; (2) to create a prediction model; and (3) to assess inter-observer agreement among radiologists.

METHODS

All available cases of thyroid nodules, surgically removed between 2000 and 2009. Three radiologists reviewed the sonographic images; 2 pathologists reviewed the tissue specimens. Adult prediction models were applied. Interobserver variability was assessed.

RESULTS

Twenty-seven subjects, mean age 13.1±3.4 years, were included. Nineteen nodules were differentiated thyroid carcinomas. On multivariate analysis, size was the only significant predictor of malignancy. On recursive partitioning analysis, size >35 mm with microcalcification and ill-defined margins yielded the best prediction model. Radiologist inter-observer agreement regarding malignancy was moderate (κ=0.50).

CONCLUSIONS

Larger size, microcalcifications and ill-defined margins on ultrasound demonstrate the best predictive model for malignancy in the pediatric population. Experienced pediatric radiologists demonstrate moderate inter-observer agreement in prediction of malignancy.

Ultrasonography Diagnosis and Imaging-Based Management of Thyroid Nodules: Revised Korean Society of Thyroid Radiology Consensus Statement and Recommendations

The rate of detection of thyroid nodules and carcinomas has increased with the widespread use of ultrasonography (US), which is the mainstay for the detection and risk stratification of thyroid nodules as well as for providing guidance for their biopsy and nonsurgical treatment. The Korean Society of Thyroid Radiology (KSThR) published their first recommendations for the US-based diagnosis and management of thyroid nodules in 2011. These recommendations have been used as the standard guidelines for the past several years in Korea. Lately, the application of US has been further emphasized for the personalized management of patients with thyroid nodules. The Task Force on Thyroid Nodules of the KSThR has revised the recommendations for the ultrasound diagnosis and imaging-based management of thyroid nodules. The review and recommendations in this report have been based on a comprehensive analysis of the current literature and the consensus of experts.

2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: The American Thyroid Association Guidelines Task Force on Thyroid Nodules and Differentiated Thyroid Cancer

BACKGROUND

Thyroid nodules are a common clinical problem, and differentiated thyroid cancer is becoming increasingly prevalent. Since the American Thyroid Association's (ATA's) guidelines for the management of these disorders were revised in 2009, significant scientific advances have occurred in the field. The aim of these guidelines is to inform clinicians, patients, researchers, and health policy makers on published evidence relating to the diagnosis and management of thyroid nodules and differentiated thyroid cancer.

METHODS

The specific clinical questions addressed in these guidelines were based on prior versions of the guidelines, stakeholder input, and input of task force members. Task force panel members were educated on knowledge synthesis methods, including electronic database searching, review and selection of relevant citations, and critical appraisal of selected studies. Published English language articles on adults were eligible for inclusion. The American College of Physicians Guideline Grading System was used for critical appraisal of evidence and grading strength of recommendations for therapeutic interventions. We developed a similarly formatted system to appraise the quality of such studies and resultant recommendations. The guideline panel had complete editorial independence from the ATA. Competing interests of guideline task force members were regularly updated, managed, and communicated to the ATA and task force members.

RESULTS

The revised guidelines for the management of thyroid nodules include recommendations regarding initial evaluation, clinical and ultrasound criteria for fine-needle aspiration biopsy, interpretation of fine-needle aspiration biopsy results, use of molecular markers, and management of benign thyroid nodules. Recommendations regarding the initial management of thyroid cancer include those relating to screening for thyroid cancer, staging and risk assessment, surgical management, radioiodine remnant ablation and therapy, and thyrotropin suppression therapy using levothyroxine. Recommendations related to long-term management of differentiated thyroid cancer include those related to surveillance for recurrent disease using imaging and serum thyroglobulin, thyroid hormone therapy, management of recurrent and metastatic disease, consideration for clinical trials and targeted therapy, as well as directions for future research.

CONCLUSIONS

We have developed evidence-based recommendations to inform clinical decision-making in the management of thyroid nodules and differentiated thyroid cancer. They represent, in our opinion, contemporary optimal care for patients with these disorders.

Thyroid ultrasound features and risk of carcinoma: a systematic review and meta-analysis of observational studies

BACKGROUND

Thyroid nodules are a common finding in the general population, and their detection is increasing with the widespread use of ultrasound (US). Thyroid cancer is found in 5-15% of cases depending on sex, age, and exposure to other risk factors. Some US parameters have been associated with increased risk of malignancy. However, no characteristic seems sufficiently reliable in isolation to diagnose malignancy. The objective of this meta-analysis was to evaluate the diagnostic performance of US features for thyroid malignancy in patients with unselected thyroid nodules and nodules with indeterminate fine-needle aspiration (FNA) cytology.

METHODS

Electronic databases were reviewed for studies published prior to July 2012 that evaluated US features of thyroid nodules and reported postoperative histopathologic diagnosis. A manual search of references of review and key articles, and previous meta-analyses was also performed. A separate meta-analysis was performed including only nodules with indeterminate cytology. Analyzed features were solid structure, hypoechogenicity, irregular margins, absence of halo, microcalcifications, central vascularization, solitary nodule, heterogeneity, taller than wide shape, and absence of elasticity.

RESULTS

Fifty-two observational studies (12,786 nodules) were included. Nine studies included nodules with indeterminate cytology as a separate category, comprising 1851 nodules. In unselected nodules, all US features were significantly associated with malignancy with an odds ratio varying from 1.78 to 35.7, and microcalcifications, irregular margins, and a taller than wide shape had high specificities (Sp; 87.8%, 83.1%, 96.6%) and positive likelihood ratios (LHR; 3.26, 2.99, 8.07). Absence of elasticity was the single feature with the best diagnostic performance (sensitivity 87.9%, Sp 86.2%, and positive LHR 6.39). The presence of central vascularization was the most specific US feature in nodules with indeterminate cytology (Sp 96% and positive LHR 2.13).

CONCLUSIONS

US features in isolation do not provide reliable information to select nodules that should have a FNA performed. A combination of US characteristics with higher likelihood ratios and consequently with higher post-test probabilities of malignancy-microcalcifications, or a taller than wide shape, or irregular margins, or absence of elasticity-will probably identify nodules with an increased risk for malignancy. Further studies are required to standardize elastography techniques and evaluate outcomes, especially in nodules with an indeterminate cytology.

The accuracy of thyroid nodule ultrasound to predict thyroid cancer: systematic review and meta-analysis

CONTEXT

Significant uncertainty remains surrounding the diagnostic accuracy of sonographic features used to predict the malignant potential of thyroid nodules.

OBJECTIVE

The objective of the study was to summarize the available literature related to the accuracy of thyroid nodule ultrasound (US) in the prediction of thyroid cancer.

METHODS

We searched multiple databases and reference lists for cohort studies that enrolled adults with thyroid nodules with reported diagnostic measures of sonography. A total of 14 relevant US features were analyzed.

RESULTS

We included 31 studies between 1985 and 2012 (number of nodules studied 18,288; average size 15 mm). The frequency of thyroid cancer was 20%. The most common type of cancer was papillary thyroid cancer (84%). The US nodule features with the highest diagnostic odds ratio for malignancy was being taller than wider [11.14 (95% confidence interval 6.6-18.9)]. Conversely, the US nodule features with the highest diagnostic odds ratio for benign nodules was spongiform appearance [12 (95% confidence interval 0.61-234.3)]. Heterogeneity across studies was substantial. Estimates of accuracy depended on the experience of the physician interpreting the US, the type of cancer and nodule (indeterminate), and type of reference standard. In a threshold model, spongiform appearance and cystic nodules were the only two features that, if present, could have avoided the use of fine-needle aspiration biopsy.

CONCLUSIONS

Low- to moderate-quality evidence suggests that individual ultrasound features are not accurate predictors of thyroid cancer. Two features, cystic content and spongiform appearance, however, might predict benign nodules, but this has limited applicability to clinical practice due to their infrequent occurrence.

An elevated level of TSH might be predictive of differentiated thyroid cancer

Suppression therapy of thyreostimulin (TSH) using thyroid hormones improves survival of subjects operated for differentiated thyroid cancer. The TSH level might be different depending on the type of nodule. The objective of this study was to compare retrospectively the TSH level between two groups of subjects who underwent total thyroidectomy for a nodule, matched on sex, ethnicity, age and biological method of TSH measurement, one whose final histology was benign and one malignant. There was no significant difference between the two groups in terms of age, sex, family history of thyroid disease or thyroid autoimmunity. The subjects, whose final histology was malignant, had a mean TSH level significantly higher than subjects with benign disease (1.55 mU/l versus 0.96 mU/l, P=0.003). Cancer risk was greater when the TSH was in the upper tertile of normal range. There was no correlation between the risk of thyroid cancer and age, sex, family history of thyroid disease, or menopausal status. The relative risk of having thyroid carcinoma was higher when the margins of nodules were blurred or in the presence of microcalcifications. These data confirm a trend toward baseline values of TSH higher in subjects with a thyroid-differentiated cancer. However, we could not define a preoperative threshold that would reliably determine the malignant or benign nature of the nodule.

Differentiation between benign and malignant solid thyroid nodules using an US classification system

Objective

To evaluate the diagnostic accuracy of a new ultrasound (US) classification system for differentiating between benign and malignant solid thyroid nodules.

Materials and Methods

In this study, we enrolled 191 consecutive patients who received real-time US and subsequent US diagnoses for solid thyroid nodules, and underwent US-guided fine-needle aspiration. Each thyroid nodule was prospectively classified into 1 of 5 diagnostic categories by real-time US: "malignant," "suspicious for malignancy," "borderline," "probably benign," and "benign". We evaluated the diagnostic accuracy of thyroid US and the cut-off US criteria by comparing the US diagnoses of thyroid nodules with cytopathologic results.

Results

Of the 191 solid nodules, 103 were subjected to thyroid surgery. US categories for these 191 nodules were malignant (n = 52), suspicious for malignancy (n = 16), borderline (n = 23), probably benign (n = 18), and benign (n = 82). A receiver-operating characteristic curve analysis revealed that the US diagnosis for solid thyroid nodules using the 5-category US classification system was very good. The sensitivity, specificity, positive and negative predictive values, and accuracy of US diagnosis were 86%, 95%, 91%, 92%, and 92%, respectively, when benign, probably benign, and borderline categories were collectively classified as benign (negative).

Conclusion

The diagnostic accuracy of thyroid US for solid thyroid nodules is high when the above-mentioned US classification system is applied.

Advances in ultrasound for the diagnosis and management of thyroid cancer

BACKGROUND

Ultrasonography (US) is increasingly being employed by endocrinologists and surgeons in the diagnosis and management of patients with thyroid nodules and thyroid cancer. Recent consensus guidelines from the American Thyroid Association highlight the importance of this modality by recommending that patients with thyroid nodules should undergo further evaluation with cervical US to stratify the risk of malignancy. Likewise, ultrasound is advocated for the preoperative and postoperative diagnosis of cervical lymph node metastases.

SUMMARY

This article will summarize the US characteristics that impart a suspicious appearance on thyroid nodules and cervical lymph nodes as well as those findings that are reassuring. Likewise, the indications for thyroid nodule and lymph node fine-needle aspiration will be reviewed. Finally, this article will briefly discuss adjunctive tools in US such as elastography, percutaneous ethanol ablation, and radiofrequency ablation.

CONCLUSIONS

US may be used to help stratify the risk of malignancy in thyroid nodules and cervical lymph nodes. This tool further aids in the diagnosis of malignancy when used in conjunction with fine-needle aspiration. US plays an important role as both a diagnostic and therapeutic tool in the evaluation of patients with neck masses.