Diagnostic accuracy of ultrasound-guided fine needle aspiration biopsy for thyroid malignancy: systematic review and meta-analysis

A Novel Training Model to Improve Diagnostic Accuracy of Cervical Fine-Needle Aspiration

INTRODUCTION

This study aims to improve the diagnostic yield of cervical fine-needle aspiration (FNA) through training on a novel liver model. Ultrasonography-guided fine-needle aspiration (US-FNA) is crucial for diagnosing head and neck lumps but requires meticulous execution. Limited resources often hinder systematic teaching, making practical models essential for training.

METHODS

Fifteen otorhinolaryngology residents trained using a liver model with inserted Sensorium spheres to simulate cervical masses. The training involved viewing an instructional video, performing US-FNA on the model, and completing pre- and posttraining self-assessments. Performance was evaluated using visual analog scales (VAS), an adapted version of objective structured assessment of ultrasound skills (adapted OSAUS), and timing of procedures. Clinical impact was assessed by comparing diagnostic rates of US-FNA before and after training.

RESULTS

Participants reported increased comfort and proficiency in US-FNA techniques posttraining. Adapted OSAUS scores improved significantly for image recognition and both in-plane and out-of-plane techniques. The diagnostic yield of US-FNA in clinical practice increased from 71% to 85%. No significant influence of gender, preferred ultrasound orientation, age, or experience on the learning curve was found. However, male participants showed a more substantial benefit from the training.

CONCLUSION

The liver model effectively enhances US-FNA skills, reflected in improved clinical diagnostic rates. Training on such models should be incorporated into medical education to reduce inconclusive punctures and enhance patient satisfaction. This study demonstrates the feasibility and effectiveness of a cost-efficient, reproducible model for US-FNA training, emphasizing the importance of practical training in medical education.

TIRADS-based artificial intelligence systems for ultrasound images of thyroid nodules: protocol for a systematic review

PURPOSE

The thyroid imaging reporting and data system (TIRADS) was developed as a standard global term to describe thyroid nodule risk features, aiming to address issues such as variability and low reproducibility in nodule feature detection and interpretation by different physicians. The objective of this study is to comprehensively study articles that utilize AI techniques to design and develop decision support systems for classifying thyroid nodule risk on the basis of various TIRADS guidelines from ultrasound images.

METHODS

This protocol includes five steps: identification of key research questions of the review, descriptions of the systematic literature search strategies, criteria for study inclusion and exclusion, study quality measures, and the data extraction process. We designed a complete search string using PubMed, Scopus, and Web of Sciences to retrieve all relevant English language studies up to January 2024. A PRISMA diagram was constructed, inclusion and exclusion criteria were defined, and after a quality assessment of the included papers, relevant data were extracted. The protocol of this systematic review was registered in the PROSPERO database (CRD42024551311).

RESULTS

We anticipate that our findings will assist researchers in creating higher-quality systems with increased efficiency, reducing unnecessary biopsies, improving the reproducibility and reliability of thyroid nodule diagnostics, and providing good educational opportunities for less experienced physicians.

CONCLUSION

In this study, a protocol was used for performing a systematic review to evaluate the diagnostic performance and other various aspects used in the design and development of artificial intelligence CAD systems based on various thyroid imaging reporting and data systems (TI-RADSs).

Integrated intraoperative predictive model for malignancy risk assessment of thyroid nodules with atypia of undetermined significance cytology

Management of thyroid nodules with atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) cytology is challenging because of uncertain malignancy risk. Intraoperative frozen section pathology provides real-time diagnosis for AUS/FLUS nodules undergoing surgery, but its accuracy is limited. This study aimed to develop an integrated predictive model combining clinical, ultrasound and IOFS features to improve intraoperative malignancy risk assessment. A retrospective cohort study was conducted on patients with AUS/FLUS cytology and negative BRAFV600E mutation who underwent thyroid surgery. The cohort was randomly divided into training and validation sets. Clinical, ultrasound, and pathological features were extracted for analysis. Three models were developed: an IOFS model with IOFS results as sole predictor, a clinical model integrating clinical and ultrasound features, and an integrated model combining all features. Model performance was evaluated using comprehensive metrics in both sets. The superior model was visualized as a nomogram. Among 531 included patients, the integrated model demonstrated superior diagnostic ability, predictive performance, calibration, and clinical utility compared to other models. It exhibited AUC values of 0.92 in the training set and 0.95 in the validation set. The nomogram provides a practical tool for estimating malignancy probability intraoperatively. This study developed an innovative integrated predictive model for intraoperative malignancy risk assessment of AUS/FLUS nodules. By combining clinical, ultrasound, and IOFS features, the model enhances IOFS diagnostic sensitivity, providing a reliable decision-support tool for optimizing surgical strategies.

Diagnostic value of combined ultrasound contrast and elastography for differentiating benign and malignant thyroid nodules: a meta-analysis

The diagnostic value of contrast-enhanced ultrasound combined with ultrasound elastography for benign and malignant thyroid nodules is still controversial, so we used meta-analysis to seek controversial answers. The PubMed, OVID, and CNKI databases were searched according to the inclusion and exclusion criteria. The literature was selected from the establishment of each database to February 2024. The QUADAS-2 tool assessed diagnostic test accuracy. SROC curves and Spearman's correlation coefficient were made by Review Manager 5.4 software to assess the presence of threshold effects in the literature. Meta-Disc1.4 software was used for Cochrane-Q and χ2 tests, which be used to evaluate heterogeneity, with P-values and I2 indicating heterogeneity levels. The appropriate effect model was selected based on the results of the heterogeneity test. Stata18.0 software was used to evaluate publication bias. The diagnostic accuracy of contrast-enhanced ultrasound combined with ultrasound elastography for benign and malignant thyroid nodules was evaluated by calculating the combined sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, DOR, and area under the SROC curve. A total of 31 studies included 3811 patients with 4718 nodules were analyzed. There is no heterogeneity caused by the threshold effect, but there is significant non-threshold heterogeneity. Combined diagnostic metrics were: sensitivity = 0.93, specificity = 0.91, DOR = 168.41, positive likelihood ratio = 10.60, and negative likelihood ratio = 0.07. The SROC curve area was 0.97. Contrast-enhanced ultrasound and elastography show high diagnostic accuracy for thyroid nodules, offering a solid foundation for early diagnosis and treatment.Trial registration. CRD42024509462.

Diagnostic Accuracy of Ultrasound and Fine-Needle Aspiration Cytology in Thyroid Malignancy

Introduction: Thyroid nodule incidence is increasing due to the widespread application of ultrasonography. Fine-needle aspiration cytology is widely applied for the detection of malignancies. The aim of this study was to evaluate the predictive value of ultrasonography in thyroid cancer. Methods: This retrospective study included patients that underwent total thyroidectomy for benign thyroid disease or well-differentiated thyroid carcinoma from January 2017 to December 2022. The study population was divided into groups: the well-differentiated thyroid cancer group and the control group with benign histopathological reports. Results: In total, 192 patients were enrolled in our study; 159 patients were included in the well-differentiated thyroid cancer group and 33 patients in the control group. Statistical analysis demonstrated that ultrasonographic findings such as microcalcifications (90.4%), hypoechogenicity (89.3%), irregular margins (92.2%) and taller-than-wide shape (90.5%) were correlated to malignancy (p < 0.001). Uni- and multivariate analysis revealed that both US score (OR: 2.177; p < 0.001) and Bethesda System (OR: 1.875; p = 0.002) could predict malignancies. In terms of diagnostic accuracy, the US score displayed higher sensitivity (64.2% vs. 33.3%) and better negative predictive value (34.5% vs. 24.4%) than the Bethesda score, while both scoring systems displayed comparable specificities (90.9% vs. 100%) and positive predictive values (97.1% vs. 100%). Discussion: The malignant potential of thyroid nodules is a crucial subject, leading the decision for surgery. Ultrasonography and fine-needle aspiration cytology are pivotal examinations in the diagnostic process, with ultrasonography demonstrating better negative predictive value.

Deep learning to assist composition classification and thyroid solid nodule diagnosis: a multicenter diagnostic study

OBJECTIVES

This study aimed to propose a deep learning (DL)-based framework for identifying the composition of thyroid nodules and assessing their malignancy risk.

METHODS

We conducted a retrospective multicenter study using ultrasound images from four hospitals. Convolutional neural network (CNN) models were constructed to classify ultrasound images of thyroid nodules into solid and non-solid, as well as benign and malignant. A total of 11,201 images of 6784 nodules were used for training, validation, and testing. The area under the receiver-operating characteristic curve (AUC) was employed as the primary evaluation index.

RESULTS

The models had AUCs higher than 0.91 in the benign and malignant grading of solid thyroid nodules, with the Inception-ResNet AUC being the highest at 0.94. In the test set, the best algorithm for identifying benign and malignant thyroid nodules had a sensitivity of 0.88, and a specificity of 0.86. In the human vs. DL test set, the best algorithm had a sensitivity of 0.93, and a specificity of 0.86. The Inception-ResNet model performed better than the senior physicians (p < 0.001). The sensitivity and specificity of the optimal model based on the external test set were 0.90 and 0.75, respectively.

CONCLUSIONS

This research demonstrates that CNNs can assist thyroid nodule diagnosis and reduce the rate of unnecessary fine-needle aspiration (FNA).

CLINICAL RELEVANCE STATEMENT

High-resolution ultrasound has led to increased detection of thyroid nodules. This results in unnecessary fine-needle aspiration and anxiety for patients whose nodules are benign. Deep learning can solve these problems to some extent.

KEY POINTS

• Thyroid solid nodules have a high probability of malignancy. • Our models can improve the differentiation between benign and malignant solid thyroid nodules. • The differential performance of one model was superior to that of senior radiologists. Applying this could reduce the rate of unnecessary fine-needle aspiration of solid thyroid nodules.

Thyroid Imaging Reporting and Data Systems: Applicability of the "Taller than Wide" Criterium in Primary/Secondary Care Units and the Role of Thyroid Scintigraphy

BACKGROUND

To examine the applicability of the "taller than wide" (ttw) criterium for risk assessment of thyroid nodules (TNs) in primary/secondary care units and the role of thyroid scintigraphy therein.

METHODS

German bicenter study performed in a setting of primary/secondary care. Patient recruitment and analysis in center A was conducted in a prospective manner. In center B, patient data were retrieved from a database that was originally generated by prospective data collection. TNs were assessed by ultrasound and thyroid scans, mostly fine needle biopsy and occasionally surgery and others. In center A, only patients who presented for the first time were included. The inclusion criterion was any TN ≥ 10 mm that had at least the following two sonographic risk features: solidity and a ttw shape. In center B, consecutive patients who had at least ttw and hypofunctioning nodules ≥ 10 mm were retrieved from the above-mentioned database. The risk of malignancy was determined according to a mixed reference standard and compared with literature data.

RESULTS

In center A, 223 patients with 259 TNs were included into the study. For further analysis, 200 nodules with a reference standard were available. The overall malignancy rate was 2.5% (upper limit of the 95% CI: 5.1%). After the exclusion of scintigraphically hyperfunctioning nodules, the malignancy rate increased slightly to 2.8% (upper limit of the 95% CI: 5.7%). Malignant nodules exhibited sonographic risk features additional to solidity and ttw shape more often than benign ones. In addition to the exclusion of hyperfunctioning nodules, when considering only nodules without additional US risk features, i.e., exclusively solid and ttw-nodules, the malignancy rate decreased to 0.9% (upper limit 95% CI: 3.7%). In center B, from 58 patients, 58 ttw and hypofunctioning TNs on thyroid scans with a reference standard were available. Malignant nodules from center B were always solid and hypoechoic. The overall malignancy rate of hypofunctioning and ttw nodules was 21%, with the lower limit of the 95% CI (one-sided) being 12%.

CONCLUSIONS

In primary/secondary care units, the lowest TIRADS categories for indicating FNB, e.g., applying one out of five sonographic risk features, may not be appropriate owing to the much lower a priori malignancy risk in TNs compared to tertiary/quaternary care units. Even the combination of two sonographic risk features, "solidity" and "ttw", may only be appropriate in a limited fashion. In contrast, the preselection of TNs according to hypofunctioning findings on thyroid scans clearly warranted FNB, even when applying only one sonographic risk criterion ("ttw"). For this reason, thyroid scans in TNs may not only be indicated to rule out hyperfunctioning nodules from FNB but also to rule in hypofunctioning ones.

Physical Examination of the Thyroid: Accuracy in Detecting Thyroid Nodules and Frequency of Additional Findings

OBJECTIVE

Thyroid palpation is a common clinical practice to detect thyroid abnormalities. However, its accuracy and potential for additional findings remain unclear. This study aimed to assess the diagnostic accuracy of physical exams in detecting thyroid nodules.

METHODS

A retrospective observational study was conducted on a random sample of adult patients who underwent their first-time thyroid ultrasound between January 2015 and September 2017, following a documented thyroid physical exam. The study assessed the performance of thyroid palpation in detecting 1 or multiple thyroid nodules, as well as the proportion of additional findings on ultrasounds due to false positive thyroid palpation.

RESULTS

We included 327 patients, mostly female (65.1%), white (84.1%), and treated in a primary care setting (54.4%) with a mean age of 50.8 years (SD 16.9). For solitary thyroid nodules, the physical exam had a sensitivity of 20.3%, specificity of 79.1%, an accuracy of 68.5%, negative predictive value of 81.8%, and positive predictive value of 17.6%. For detecting a multinodular goiter, physical exams demonstrated a sensitivity of 10.8%, specificity of 96.5%, accuracy of 55.4%, negative predictive value of 53.9, and positive predictive value of 73.9%. Among 154 cases with palpable nodules, 60% had additional nodules found in subsequent thyroid ultrasound.

CONCLUSION

Thyroid physical exam has limited diagnostic performance and leads to additional findings when followed by a thyroid ultrasound. Future efforts should be directed at improving the accuracy of thyroid physical exams or re-evaluating its routine use.

Approach to Thyroid Nodules: Diagnosis and Treatment

Thyroid nodules (TNs) are prevalent and found in up to 50% of individuals. While most TNs are benign, some can be malignant. The evaluation of TNs is crucial to rule out malignancy and identify those requiring surgical intervention. This study aimed to clarify the reported prevalence of TNs, focusing specifically on their various types, assessment and diagnostic processes, current evaluation methods, and evidence-based management. It also provides recommendations for follow-up. TNs are typically found during physical exams or incidentally during imaging procedures. Routine laboratory and clinical evaluations of TNs are common. Ultrasound is the preferred imaging method to determine if a TN needs a biopsy. Fine-needle aspiration (FNA) is crucial in deciding whether surgery or surveillance is necessary. TNs that show suspicious features on the ultrasound may require cytologic analysis to assess the risk of malignancy. The effectiveness of several supplementary molecular tests is still uncertain, although some studies report promising results. The management and treatment approach for TNs primarily depends on the results of FNA cytology and ultrasound characteristics. The optimal treatment strategy for TNs ranges from straightforward follow-ups for low-risk cases to surgical intervention for high-risk patients. Rather than adopting a uniform approach, clinicians should assess each patient on a case-by-case basis using current knowledge and a collaborative, multidisciplinary method.

Modified American College of Radiology Thyroid Imaging Reporting and Data System and Modified Artificial Intelligence Thyroid Imaging Reporting and Data System for Thyroid Nodules: A Multicenter Retrospective Study

Background: Risk stratification systems for thyroid nodules are limited by low specificity. The fine-needle aspiration (FNA) biopsy size thresholds and stratification criteria are based on evidence from the literature and expert consensus. Our aims were to investigate the optimal FNA biopsy size thresholds in the American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS) and artificial intelligence (AI) TI-RADS and to revise the stratification criteria in AI TI-RADS. Methods: A total of 2596 thyroid nodules (in 2511 patients) on ultrasound examination with definite pathological diagnoses were retrospectively identified from January 2017 to September 2021 in 6 participating Chinese hospitals. The modified criteria for ACR TI-RADS were as follows: (1) no FNA for TR3; (2) FNA threshold for TR4 increased to 2.5 cm. The modified criteria for AI TI-RADS were as follows: (1) 6-point nodules upgraded to TR5; (2) no FNA for TR3; (3) FNA threshold for TR4 increased to 2.5 cm. The diagnostic performance and the unnecessary FNA rate (UFR) of modified versions were compared with the original ACR TI-RADS. Results: Compared with the original ACR TI-RADS, the modified ACR (mACR) TI-RADS yielded higher specificity (73% vs. 46%), accuracy (74% vs. 51%), area under the receiver operating characteristic curve (AUC; 0.80 vs. 0.70), and lower UFR (25% vs. 48%; all p < 0.001), although the sensitivity was slightly decreased (87% vs. 93%, p = 0.057). Compared with the original ACR TI-RADS, the modified AI (mAI) TI-RADS yielded higher specificity (73% vs. 46%), accuracy (75% vs. 51%), AUC (0.81 vs. 0.70), and lower UFR (24% vs. 48%; all p < 0.001), although the sensitivity tended to be slightly decreased (89% vs. 93%, p = 0.13). There was no significant difference between the mACR TI-RADS and mAI TI-RADS in the diagnostic performance and UFR (all p > 0.05). Conclusions: The revised FNA thresholds and the stratification criteria of the mACR TI-RADS and mAI TI-RADS may be associated with improvements in specificity and accuracy, without significantly sacrificing sensitivity for malignancy detection.

Frequency of thyroid pathologies in the central Black Sea Region: Ultrasound-based field study

Background

Thyroid pathologies are very common diseases. The most common thyroid pathologies are goiter and thyroid nodules. Thyroid ultrasonography is the most widely used examination method in the evaluation of thyroid pathologies. The aim of this field study is to determine the frequency of thyroid pathologies in the province of Tokat and to evaluate its relationship with some factors such as gender and dietary habits.

Materials and Methods

In this population-based prospective study, thyroid US examination was performed on a total of 822 patients. The examination procedure was carried out by one radiologist with at least 10 years of experience. During the examination, thyroid dimensions, parenchyma echo, presence of nodule, echo if any, number, size, and localization were evaluated. The relationships between thyroid pathologies and age, gender, body mass index (BMI), and chronic diseases in the participants were evaluated.

Results

Up to 45.2% (n = 372) of the participants were male and 54.8% (n = 417) were female. The ages of the participants ranged from 20 to 87 years. The mean age of the participants was 47.2. Up to 9.8% of the participants had an increase in thyroid size, defined as goiter. Parenchyma was homogeneous in 72.1% of the participants and heterogeneous in 27.9%. Thyroid nodules were present in the thyroid gland in 40.8% of the participants. There was a statistically significant relationship between thyroid pathologies and female gender, age, and obesity.

Conclusion

Thyroid diseases show regional differences. Older age, female gender, and obesity increase the frequency of thyroid pathologies.

Predicting malignancy in thyroid nodules based on conventional ultrasound and elastography: the value of predictive models in a multi-center study

BACKGROUND

This study aimed to establish predictive models based on features of Conventional Ultrasound (CUS) and elastography in a multi-center study to determine appropriate preoperative diagnosis of malignancy in thyroid nodules with different risk stratification based on 2017 Thyroid Imaging Reporting and Data System by the American College of Radiology (ACR TI-RADS) guidelines.

METHODS

Five hundred forty-eight thyroid nodules from three centers pathologically confirmed by the cytology or histology were retrospectively enrolled in the study, which were examined by CUS and elastography before fine needle aspiration (FNA) and surgery. Characteristics of CUS of thyroid nodules were reviewed according to 2017 ACR TI-RADS. Binary logistic regression analysis was used to develop the prediction models based on the different risk stratification of CUS features and elastography which were statistically significant. Values of predictive models were evaluated regarding the discrimination and calibration.

RESULTS

Binary logistic regression showed that patients' age, taller-than-wider, lobulated or irregular boundary, extra-thyroid extension, microcalcification and the elastic parameter of Virtual touch tissue imaging quantification (VTIQ) max were independent predictors for thyroid malignancy (p < 0.05) in the ACR model and showed the area under the curve (AUC) in training (0.912) and validation cohort (internal and external: 0.877 vs 0.935). Predictive models showed predictors in ACR TR4 and TR5 for malignancy and diagnostic performance of AUC in training, internal and external validation cohort respectively: the VTIQ max (p < 0.001) with AUC of 0.809 vs 0.842 vs 0.705 and the age, taller than wide, VTIQ max variables with AUC of 0.859 vs 0.830 vs 0.906 in validation cohort. All predictive models have better calibration capabilities (p > 0.05).

CONCLUSIONS

Predictive models combined CUS and elastography features would aid clinicians to make appropriate preoperative diagnosis of thyroid nodules among different risk stratification. The elastography parameter of VTIQ max has the priority in distinguishing thyroid malignancy with moderately suspicious (ACR TR4).

Clinical knowledge embedded method based on multi-task learning for thyroid nodule classification with ultrasound images

Objective. Thyroid nodules are common glandular abnormality that need to be diagnosed as benign or malignant to determine further treatments. Clinically, ultrasonography is the main diagnostic method, but it is highly subjective with severe variability. Recently, many deep-learning-based methods have been proposed to alleviate subjectivity and achieve good results yet, these methods often neglect important guidance from clinical knowledge. Our objective is to utilize such guidance for accurate and reliable thyroid nodule classification.Approach. In this study, a multi-task learning model embedded with clinical knowledge of ACR Thyroid Imaging, Reporting and Data System guideline is proposed. The clinical features defined in the guideline have strong correlations with malignancy and they were modeled as tasks alongside the pathological type. Multi-task learning was utilized to exploit the correlations to improve diagnostic performance. To alleviate the impact of noisy labels on clinical features, a loss-weighting strategy was proposed. Five-fold cross-validation was applied to an internal training set of size 4989, and an external test set of size 243 was used for evaluation.Main results. The proposed multi-task learning model achieved an average AUC of 0.901 and an ensemble AUC of 0.917 on the test set, which significantly outperformed the single-task baseline models.Significance. The results indicated that multi-task learning of clinical features can effectively classify thyroid nodules and reveal the possibility of using clinical indicators as auxiliary tasks to improve performance when diagnosing other diseases.

Contrast-enhanced ultrasound and shear wave elastography in the diagnosis of ACR TI-RADS 4 and 5 category thyroid nodules coexisting with Hashimoto's thyroiditis

Objective

This study aims to evaluate the value of contrast-enhanced ultrasound (CEUS), shear wave elastography (SWE), and their combined use in the differentiation of American College of Radiology (ACR) thyroid imaging reporting and data system (TI-RADS) 4 and 5 category thyroid nodules coexisting with Hashimoto's thyroiditis (HT).

Materials and methods

A total of 133 pathologically confirmed ACR TI-RADS 4 and 5 category nodules coexisting with HT in 113 patients were included; CEUS and SWE were performed for all nodules. The sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), accuracy, and the area under the receiver operating characteristic curve (AUC) of the SWE, CEUS, and the combined use of both for the differentiation of benign and malignant nodules were compared, respectively.

Results

Using CEUS alone, the sensitivity, specificity, PPV, NPV, and accuracy were 89.2%, 66.0%, 81.3%, 78.6%, and 80.5%, respectively. Using SWE alone, Emax was superior to Emin, Emean, and Eratio for the differentiation of benign and malignant nodules with the best cutoff Emax >46.8 kPa, which had sensitivity of 65.1%, specificity of 90.0%, PPV of 91.5%, NPV of 60.8%, and accuracy of 74.4%, respectively. Compared with the diagnostic performance of qualitative CEUS or/and quantitative SWE, the combination of CEUS and SWE had the best sensitivity, accuracy, and AUC; the sensitivity, specificity, PPV, NPV, accuracy, and AUC were 94.0%, 66.0%, 82.1%, 86.8%, 83.5%, and 0.80 (95% confidence interval: 0.713, 0.886), respectively.

Conclusion

In conclusion, CEUS and SWE were useful for the differentiation of benign and malignant ACR TI-RADS 4 and 5 category thyroid nodules coexisting with HT. The combination of CEUS and SWE could improve the sensitivity and accuracy compared with using CEUS or SWE alone. It could be a non-invasive, reliable, and useful method to differentiate benign from malignant ACR TI-RADS 4 and 5 category thyroid nodules coexisting with HT.

Incorporation of a machine learning pathological diagnosis algorithm into the thyroid ultrasound imaging data improves the diagnosis risk of malignant thyroid nodules

Objective

This study aimed at establishing a new model to predict malignant thyroid nodules using machine learning algorithms.

Methods

A retrospective study was performed on 274 patients with thyroid nodules who underwent fine-needle aspiration (FNA) cytology or surgery from October 2018 to 2020 in Xianyang Central Hospital. The least absolute shrinkage and selection operator (lasso) regression analysis and logistic analysis were applied to screen and identified variables. Six machine learning algorithms, including Decision Tree (DT), Extreme Gradient Boosting (XGBoost), Gradient Boosting Machine (GBM), Naive Bayes Classifier (NBC), Random Forest (RF), and Logistic Regression (LR), were employed and compared in constructing the predictive model, coupled with preoperative clinical characteristics and ultrasound features. Internal validation was performed by using 10-fold cross-validation. The performance of the model was measured by the area under the receiver operating characteristic curve (AUC), accuracy, precision, recall, F1 score, Shapley additive explanations (SHAP) plot, feature importance, and correlation of features. The best cutoff value for risk stratification was identified by probability density function (PDF) and clinical utility curve (CUC).

Results

The malignant rate of thyroid nodules in the study cohort was 53.2%. The predictive models are constructed by age, margin, shape, echogenic foci, echogenicity, and lymph nodes. The XGBoost model was significantly superior to any one of the machine learning models, with an AUC value of 0.829. According to the PDF and CUC, we recommended that 51% probability be used as a threshold for determining the risk stratification of malignant nodules, where about 85.6% of patients with malignant nodules could be detected. Meanwhile, approximately 89.8% of unnecessary biopsy procedures would be saved. Finally, an online web risk calculator has been built to estimate the personal likelihood of malignant thyroid nodules based on the best-performing ML-ed model of XGBoost.

Conclusions

Combining clinical characteristics and features of ultrasound images, ML algorithms can achieve reliable prediction of malignant thyroid nodules. The online web risk calculator based on the XGBoost model can easily identify in real-time the probability of malignant thyroid nodules, which can assist clinicians to formulate individualized management strategies for patients.

Diagnostic Accuracy of Fine-Needle Biopsy in the Detection of Thyroid Malignancy: A Systematic Review and Meta-analysis

Importance

Fine-needle biopsy (FNB) became a critical part of thyroid nodule evaluation in the 1970s. It is not clear how diagnostic accuracy of FNB has changed over time.

Objective

To conduct a systematic review and meta-analysis estimating the accuracy of thyroid FNB for diagnosis of malignancy in adults with a newly diagnosed thyroid nodule and to characterize changes in accuracy over time.

Data Sources

PubMed, SCOPUS, and Cochrane Central Register of Controlled Trials were searched from 1975 to 2020 using search terms related to FNB accuracy in the thyroid.

Study Selection

English-language reports of cohort studies or randomized trials of adult patients undergoing thyroid FNB with sample size of 20 or greater and using a reference standard of surgical histopathology or clinical follow-up were included. Articles that examined only patients with known thyroid disease or focused on accuracy of novel adjuncts, such as molecular tests, were excluded. Two investigators screened each article and resolved conflicts by consensus. A total of 36 of 1023 studies met selection criteria.

Data Extraction and Synthesis

The MOOSE guidelines were used for data abstraction and assessing data quality and validity. Two investigators abstracted data using a standard form. Studies were grouped into epochs by median data collection year (1975 to 1990, 1990 to 2000, 2000 to 2010, and 2010 to 2020). Data were pooled using a bivariate mixed-effects model.

Main Outcomes and Measures

The primary outcome was accuracy of FNB for diagnosis of malignancy. Accuracy was hypothesized to increase in later time periods, a hypothesis formulated prior to data collection.

Results

Of 16 597 included patients, 12 974 (79.2%) were female, and the mean (SD) age was 47.3 (12.9) years. The sensitivity of FNB was 85.6% (95% CI, 79.9-89.5), the specificity was 71.4% (95% CI, 61.1-79.8), the positive likelihood ratio was 3.0 (95% CI, 2.3-4.1), and the negative likelihood ratio was 0.2 (95% CI, 0.2-0.3). The area under the receiver operating characteristic curve was 86.1%. Epoch was not significantly associated with accuracy. None of the available covariates could explain observed heterogeneity.

Conclusions and Relevance

Accuracy of thyroid FNB has not significantly changed over time. Important developments in technique, preparation, and interpretation may have occurred too heterogeneously to capture a consistent uptrend over time. FNB remains a reliable test for thyroid cancer diagnosis.

Deep learning for the diagnosis of suspicious thyroid nodules based on multimodal ultrasound images

OBJECTIVES

This study aimed to differentially diagnose thyroid nodules (TNs) of Thyroid Imaging Reporting and Data System (TI-RADS) 3-5 categories using a deep learning (DL) model based on multimodal ultrasound (US) images and explore its auxiliary role for radiologists with varying degrees of experience.

METHODS

Preoperative multimodal US images of 1,138 TNs of TI-RADS 3-5 categories were randomly divided into a training set (n = 728), a validation set (n = 182), and a test set (n = 228) in a 4:1:1.25 ratio. Grayscale US (GSU), color Doppler flow imaging (CDFI), strain elastography (SE), and region of interest mask (Mask) images were acquired in both transverse and longitudinal sections, all of which were confirmed by pathology. In this study, fivefold cross-validation was used to evaluate the performance of the proposed DL model. The diagnostic performance of the mature DL model and radiologists in the test set was compared, and whether DL could assist radiologists in improving diagnostic performance was verified. Specificity, sensitivity, accuracy, positive predictive value, negative predictive value, and area under the receiver operating characteristics curves (AUC) were obtained.

RESULTS

The AUCs of DL in the differentiation of TNs were 0.858 based on (GSU + SE), 0.909 based on (GSU + CDFI), 0.906 based on (GSU + CDFI + SE), and 0.881 based (GSU + Mask), which were superior to that of 0.825-based single GSU (p = 0.014, p< 0.001, p< 0.001, and p = 0.002, respectively). The highest AUC of 0.928 was achieved by DL based on (G + C + E + M)US, the highest specificity of 89.5% was achieved by (G + C + E)US, and the highest accuracy of 86.2% and sensitivity of 86.9% were achieved by DL based on (G + C + M)US. With DL assistance, the AUC of junior radiologists increased from 0.720 to 0.796 (p< 0.001), which was slightly higher than that of senior radiologists without DL assistance (0.796 vs. 0.794, p > 0.05). Senior radiologists with DL assistance exhibited higher accuracy and comparable AUC than that of DL based on GSU (83.4% vs. 78.9%, p = 0.041; 0.822 vs. 0.825, p = 0.512). However, the AUC of DL based on multimodal US images was significantly higher than that based on visual diagnosis by radiologists (p< 0.05).

CONCLUSION

The DL models based on multimodal US images showed exceptional performance in the differential diagnosis of suspicious TNs, effectively increased the diagnostic efficacy of TN evaluations by junior radiologists, and provided an objective assessment for the clinical and surgical management phases that follow.

Comparison of diagnostic accuracy and utility of artificial intelligence-optimized ACR TI-RADS and original ACR TI-RADS: a multi-center validation study based on 2061 thyroid nodules

OBJECTIVE

To determine if artificial intelligence-based modification of the Thyroid Imaging Reporting Data System (TI-RADS) would be better than the current American College of Radiology (ACR) TI-RADS for risk stratification of thyroid nodules.

METHODS

A total of 2061 thyroid nodules (in 1859 patients) sampled with fine-needle aspiration or operation were retrospectively analyzed between January 2017 and July 2020. Two radiologists blinded to the pathologic diagnosis evaluated nodule features in five ultrasound categories and assigned TI-RADS scores by both ACR TI-RADS and AI TI-RADS. Inter-rater agreement was assessed by asking another two radiologists to score a set of 100 nodules independently. The reference standard was postoperative pathological or cytopathological diagnosis according to the Bethesda system. Inter-rater agreement was determined using intraclass correlation coefficient (ICC).

RESULTS

AI TI-RADS assigned lower TI-RADS risk levels than ACR TI-RADS (p < 0.001) and had larger area under receiver operating characteristic curve (0.762 vs. 0.679, p < 0.001). The sensitivities of ACR TI-RADS and AI TI-RADS were similar (86.7% vs. 82.2%, p = 0.052), but specificity was higher with AI TI-RADS (70.2% vs. 49.2%, p < 0.001). AI TI-RADS downgraded 743 (48.63%) benign nodules, indicating that 328 (42.3% of 776 biopsied nodules) unnecessary fine-needle aspirations (FNA) could have been avoided. Inter-rater agreement was better with AI TI-RADS than with ACR TI-RADS (ICC, 0.808 vs. 0.861, p < 0.001).

CONCLUSION

AI TI-RADS can achieve meaningful reduction in the number of benign thyroid nodules recommended for biopsy and significantly improve specificity despite a slight decrease in sensitivity.

KEY POINTS

• AI TI-RADS assigned lower TI-RADS risk levels than ACR TI-RADS, showing similar sensitivity but higher specificity. • Half of the benign nodules can be downgraded of which 42.3% of biopsy nodules avoided unnecessary fine-needle aspiration (FNA). • AI TI-RADS had a better overall inter-rater agreement.

Diagnostic accuracy of palpation versus ultrasound-guided fine needle aspiration biopsy for diagnosis of malignancy in thyroid nodules: a systematic review and meta-analysis

Thyroid nodule is a common health problem in endocrinology. Thyroid fine-needle aspiration biopsy (FNAB) cytology performed by palpation guided FNAB (PGFNAB) and ultrasound-guided FNAB (USGFNAB) are the preferred examinations for the diagnosis of thyroid cancer and part of the integration of the current thyroid nodule assessment. Although studies have shown USGFNAB to be more accurate than PGFNAB, inconsistencies from several studies and clinical guidelines still exist.The purpose of this study is to compare the diagnostic accuracy of Palpation versus Ultrasound-Guided Fine Needle Aspiration Biopsy in diagnosing malignancy of thyroid nodules.The systematic review and meta-analysis were prepared based on the PRISMA standards. Literature searches were carried out on three online databases (Pubmed/MEDLINE, Embase, and Proquest) and grey literatures. Data extraction was carried out manually from various studies that met the eligibility, followed by analysis to obtain pooled data on sensitivity, specificity, Diagnostic Odds Ratio (DOR) and Area Under Curve (AUC), and the comparison of the two methods.Total of 2517 articles were obtained, with 11 studies were included in this systematic review. The total sample was 2382, including 1128 subjects using PGFNAB and 1254 subjects using USGFNAB. The risk of bias was assessed using QUADAS-2 with mild-moderate results. The results of sensitivity, specificity, AUC and DOR in diagnosing thyroid nodules using PGFNAB were 76% (95% CI, 49-89%), 77% (95% CI, 56-95%), 0.827 and 11.6 (95% CI, 6-21) respectively. The results of sensitivity, specificity, AUC and DOR in diagnosing thyroid nodules using USGFNAB were 90% (95% CI, 81-95%), 80% (95% CI, 66-89%), 0.92 and 40 (95% CI, 23-69), respectively the results of the comparison test between PGFNAB and USGFNAB; Tsens USGFNAB of 0.99 (p = 0.023), AUC difference test of 0.093 (p = 0.000023).The diagnostic accuracy of USGFNAB is higher than PGFNAB in diagnosing malignancy of thyroid nodules. If it is accessible, the author recommends using USGFNAB as a diagnostic tool for thyroid nodules.

Elastography and Doppler May Bring a New Perspective to TIRADS, Altering Conventional Ultrasonography Dominance

RATIONALE AND OBJECTIVES

The main aim of ultrasonography (US) examining thyroid nodules is to differentiate malignant nodules from benign nodules. Several professional societies and groups of investigators have defined guidelines such as Thyroid Imaging Reporting and Data System (TIRADS) to provide the standardized language and approach to thyroid nodules. This study is aimed to investigate the compatibility of such classification systems with the pathological diagnosis of nodules and evaluate the contribution of the Shear-wave elastography (SWE) and Doppler ultrasonography (DUS) findings.

MATERIALS AND METHODS

This is a prospective study. Patients with thyroid US exams between December 2017 and April 2019 were included. In the study, eligible 210 nodules from 210 patients were enrolled. For stratification, the conventional B-mode US, SWE and DUS were performed. According to Kwak, American College of Radiology (ACR), and European (EU)-TIRADS, Nodules were classified separately, and a new scoring system whose the criteria was put defined in the study has developed.

RESULTS

For SWE; Emean cut-off value was 33 kPa with a sensitivity and specificity of 95,6% (95% CI: 0,85-0,98) and 95% (95% CI:0,90-0,97) respectively (p <0.001). For spectral DUS; resistivity index (RI) cut-off value was 0.64 with a sensitivity and specificity of 73,3% (95% CI:0,59-0,83) and 80% (95% CI:0,73-0,85) respectively (p <0.001). Kwak TIRADS, American College of Radiology TIRADS, EU-TIRADS, and new system were compared by ROC curve analysis. The new system has the highest sensitivity, specificity, PPV, NPV, accuracy, and AUC compared to others.

CONCLUSIONS

The new scoring system has shown that SWE and DUS findings may alter the categorization in TIRADS and increase sensitivity and specificity.

Fine-Needle Aspiration Under Guidance of Ultrasound Examination of Thyroid Lesions

Fine-needle aspiration biopsy is the most common method for preoperative diagnosis of thyroid carcinomas including papillary carcinoma. The procedure is best performed with ultrasound by operator with professional skill and knowledge. Several guidelines recommend the indication of fine-needle aspiration concerning the pattern of ultrasound and size of nodules. Besides, fine-needle aspiration biopsy of lymph nodes should be performed if malignancies are suspected. Fine-needle aspiration biopsy of thyroid gland is mostly safe, but complications such as blood extravasation-related complications, acute thyroid enlargement, infection in thyroid gland, and pneumothorax could occur. The most frequent complications are blood extravasation-related complications, which could be fatal. Similarly, acute thyroid enlargement could also be severe. To conclude, fine-needle aspiration biopsy is useful and should be performed under the precise indication and the updated knowledge of complications including the way of handling if they occur.

The impact of the use of the ACR-TIRADS as a screening tool for thyroid nodules in a cancer center

BACKGROUND

The Thyroid Imaging Reporting and Data System (TIRADS) was created to assess risk of thyroid nodules through ultrasound. Plenty classifications methods for thyroid nodules have already been created, but none of them have yet achieved global utilization. This study analyzed the performance of the American College of Radiology (ACR) TIRADS, its reproducibility and the impact of its utilization as a screening method in a large Cancer Center cohort.

METHODS

Thyroid nodules which underwent fine-needle aspiration (FNA) in a 1-year period were selected, with their ultrasound images retrospectively classified according to the ACR TI-RADS. Cytological evaluation of the nodules and final histology (whenever available) was used to assess risk of neoplasm (RON) and risk of malignancy (ROM) associated to each ACR-TIRADS category. Further analyses were also carried out according to recommendation or not of FNA by the ACR-TIRADS and nodule size. Inter-observer agreement for the system was also assessed.

RESULTS

A total of 1112 thyroid nodules were included. RON for each category according to final cytological diagnosis was 0% for TR1 and TR2, 2.1% for TR3; 15.6% for TR4 and 68.9% for TR5. No significant difference was observed between the RON of the categories for cases above or below 1.0 cm. Nodules that met the criteria for FNA had 3 times greater chance of a positive outcome. Substantial agreement (kappa 0.77) was seen between two different observers.

CONCLUSIONS

ACR TI-RADS scoring system has demonstrated to be an accurate method to stratify thyroid nodules in a Cancer Center, with a high reproducibility.

Improving the diagnosis of AUS/FLUS thyroid nodules using an algorithm with combination of BRAFV600E mutation analysis and ultrasound pattern-based risk stratification

PURPOSE

To propose a diagnostic algorithm for improving the diagnosis of atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS) thyroid nodules.

METHODS

This study retrospectively enrolled 77 consecutive patients with 81 AUS/FLUS nodules who underwent preoperative BRAFV600E mutation analysis. A new diagnostic algorithm was proposed that BRAFV600E mutation analysis for the Fine-needle aspiration cytology specimen was firstly carried out, in which positive BRAFV600E mutation indicated malignancy and classification of the nodules with negative BRAFV600E mutation was further performed based on ultrasound pattern-based risk stratification of American Thyroid Association Guidelines. The diagnostic performance of the new diagnostic algorithm was evaluated.

RESULTS

The sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and area under the receiver operating characteristic curve (AUROC) of new diagnostic algorithm were 94.6%, 84.0%, 91.4%, 86.9%, 90.1%, and 0.893, respectively. The proposed diagnostic algorithm significantly increased the diagnostic performances (AUROC: 0.893 vs. 0.837 and 0.795), sensitivity (94.6% vs. 71.4% and 75.0%), and accuracy (90.1% vs. 79.0% and 77.8%) compared with BRAFV600E mutation analysis alone and ultrasound pattern-based risk stratification alone (all P < 0.05).

CONCLUSION

The proposed diagnostic algorithm is helpful for improving the diagnosis of AUS/FLUS nodules, which might be as a routine approach.

The Diagnostic Value of the American College of Radiology Thyroid Imaging Reporting and Data System Classification and Shear-Wave Elastography for the Differentiation of Thyroid Nodules

This study aimed to determine the diagnostic accuracy of the American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) classification and shear-wave elastography (SWE) for the diagnosis of benign and malignant thyroid nodules. This retrospective study enrolled 141 patients (18-84 y of age) undergoing thyroidectomy between January 2015 and August 2020. All statistical analysis was based on pathologic results of patients. The cut-off value was found as category 4 for ACR TI-RADS classification and 5 m/s for shear-wave velocity (Vs) by the receiver operator characteristic curve analysis (area under the curve [AUC] = 0.684, p = 0.020 and AUC = 0.715, p = 0.005, respectively). SWE has higher diagnostic accuracy than the ACR TI-RADS classification system and can improve thyroid nodule discrimination in all sizes of the nodules. Also, the diagnostic performance decreases when the nodule diameter increases.

Thyroid Nodule Evaluation and Management in Older Adults: A Review of Practical Considerations for Clinical Endocrinologists

OBJECTIVE

Contextualizing the evaluation of older adults with thyroid nodules is necessary to fully understand which management strategy is the most appropriate. Our goal was to summarize available clinical evidence to provide guidance in the care of older adults with thyroid nodules and highlight special considerations for thyroid nodule evaluation and management in this population.

METHODS

We conducted a literature search of PubMed and Ovid MEDLINE from January 2000 to November 2020 to identify relevant peer-reviewed articles published in English. References from the included articles as well as articles identified by the authors were also reviewed.

RESULTS

The prevalence of thyroid nodules increases with age. Although thyroid nodules in older adults have a lower risk of malignancy, identified cancers are more likely to be of high-risk histology. The goals of thyroid nodule evaluation and the tools used for diagnosis are similar for older and younger patients with thyroid nodules. However, limited evidence exists regarding thyroid nodule evaluation and management to guide personalized decision making in the geriatric population.

CONCLUSION

Considering patient context is significant in the diagnosis and management of thyroid nodules in older adults. When making management decisions in this population, it is essential to carefully weigh the risks and benefits of thyroid nodule diagnosis and treatment, in view of older adults' higher prevalence of high-risk thyroid cancer as well as increased risk for multimorbidity, functional and cognitive decline, and treatment complications.

Standardization of thyroid fine needle aspiration procedure and outcomes within an endocrine surgery department

Background

Fine needle aspiration (FNA) biopsy is an essential procedure for thyroid nodules. Although, the efficacy of surgeon-performed thyroid FNA biopsies has been demonstrated in the literature, there are insufficient data regarding how to establish an efficient program with a low insufficiency rate within a group practice.

Methods

An endocrine surgery thyroid FNA biopsy program was established in 2000 by one surgeon, with training of additional partners during fellowship and upon recruitment. The results within 18 years were analyzed. The FNA biopsies were performed by endocrine surgeons under ultrasound guidance without on-site pathologist review.

Results

A total of 5,469 FNA biopsies were performed by 7 surgeons. The total number of FNA biopsies performed by each surgeon varied between 291-1,378. FNA biopsies were performed in 2 passes using 22-gauge needles under constant suction. The overall insufficiency rate was 4.3%, with individual surgeon rates ranging between 2.7% and 7.2%. The insufficiency rate for the whole team ranged between 3.3% and 5% when examined in 5-year blocks.

Conclusions

This study shows that an establishment of a highly efficient thyroid FNA biopsy program within a group practice is possible with a structured endocrine surgical training and adoption of a standard technique.

Comprehensive Identification of Potential Crucial Genes and miRNA-mRNA Regulatory Networks in Papillary Thyroid Cancer

Background

Thyroid cancer is the most common endocrine malignancy, with a recent global increase of 20% in age-related incidence. Ultrasonography and ultrasonography-guided fine-needle aspiration biopsy (FNAB) are the most widely used diagnostic tests for thyroid nodules; however, it is estimated that up to 25% of thyroid biopsies are cytologically inconclusive. Molecular markers can help guide patient-oriented and targeted treatment of thyroid nodules and thyroid cancer.

Methods

Datasets related to papillary thyroid cancer (PTC) or thyroid carcinoma (GSE129562, GSE3678, GSE54958, GSE138042, and GSE124653) were downloaded from the GEO database and analysed using the Limma package of R software. For functional enrichment analysis, the Kyoto Encyclopedia of Genes and Genomes pathway analysis and Gene Ontology were applied to differentially expressed genes (DEGs) using the Metascape website. A protein-protein interaction (PPI) network was built from the STRING database. Gene expression, protein expression, immunohistochemistry, and potential functional gene survival were analysed using the GEPIA website, the Human Protein Atlas website, and the UALCAN website. Potential target miRNAs were predicted using the miRDB and Starbase datasets.

Results

We found 219 upregulated and 310 downregulated DEGs, with a cut-off of p < 0.01 and ∣log FC | >1.5. The DEGs in papillary thyroid cancer were mainly enriched in extracellular structural organisation. At the intersection of the PPI network and Metascape MCODEs, the hub genes in common were identified as FN1, APOE, CLU, and SDC2. In the targeted regulation network of miRNA-mRNA, the hsa-miR-424-5p was found to synchronously modulate two hub genes. Survival analysis showed that patients with high expression of CLU and APOE had better prognosis.

Conclusions

CLU and APOE are involved in the molecular mechanism of papillary thyroid cancer. The hsa-miR-424-5p might have the potential to reverse the processes of papillary thyroid cancer by modulating the hub genes. These are potential targets for the treatment of patients with papillary thyroid cancer.

Thyroid Nodules Located in the Lower Pole Have a Higher Risk of Malignancy than Located in the Isthmus: A Single-Center Experience

PURPOSE

The aim of our study is to investigate whether thyroid nodules (TNs) localization has value as a predictor of malignancy. Ultrasonography provides very valuable information in the evaluation of TNs, but it does not correlate perfectly with histopathologic findings. Therefore, studies that will include new diagnostic methods that can improve these unknowns can be welcomed gratefully.

METHODS

This study was carried out retrospectively in a tertiary care center from September 2016 to January 2020. The study included 862 adult patients who have one or more nodules. Ultrasonography of characteristics of nodules such as echogenicity, content, margins, calcifications, size, and localization was recorded. Fine-needle aspiration biopsy (FNAB) was performed on dominant and suspicious 1142 nodules.

RESULTS

The patients were composed of 692 (80.3%) females and 170 (19.7%) males. Compared to nodules located in the isthmus; the malignancy risk increased 8.39 (OR: 8.39 (2.34-30.12), p = 0.001) times in the lower pole, 4.27 (OR: 4.27 (1.16-15.72), p = 0.029), times in the middle pole, 8.09 (OR: 8.09 (2.11-30.94), p = 0.002) times in the upper pole, and 7.63 (OR: 7.63 (1.95-29.81), p = 0.003) times in the nodules covering the whole of the lobe. Although the most nodular location was in the middle pole, the risk of malignancy was less than that in the lower and upper poles.

CONCLUSIONS

Unlike the other localization studies, we found a higher risk of malignancy in the lower and similarly upper thyroid poles. Besides well-defined malignancy indicators in the literature and guidelines, localization information is promising for this purpose in the future.

Evaluation of the Bethesda System and the ACR TIRADS in an Endemic Goiter Region

BACKGROUND

Various factors can affect incidence of thyroid disorders and disease profiles may show abrupt changes in endemic goitrous areas. In this study, it was aimed to analyze the American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS) and the Bethesda System for Reporting Thyroid Cytopathology (BSRTC) in terms of risk of malignancy and general recommendations in an endemic goiter region (EGR).

METHODS

In this retrospective study, a total of 500 patients who had thyroidectomy following thyroid fine needle aspiration biopsy were enrolled. For the assessment of thyroid cytology, BSRTC was used and for the evaluation of ultrasound features of thyroid nodules, ACR TIRADS lexicon was adopted. For the assessment of thyroid cytology, Bethesda classification was used and for the evaluation of ultrasound features of thyroid nodules, ACR TIRADS lexicon was adopted.

RESULTS

In the EGR setting, benign category of BSRTC had a cancer risk of 6.2% which was two times more than the 2017 BSRTC revision reported. Nodules 10-14.9 mm in diameter had nearly 4 times higher malignancy risk than nodules >15 mm. In this group of patients, the risk of malignancy for TIRADS level 1, 2, 3, 4 and 5 was 1.16%, 2.94%, 7%, 45.64% and 94.44%, respectively. The malignancy rates for Bethesda system category I, II, III, IV, V and VI were as follows: 14.43%, 6.2%, 19.05%, 36.73%, 75.68% and 100%.

CONCLUSIONS

There are slight differences between the common set of standards and this study results regarding risk of malignancy. This brings up the question whether there is need for revision for the use of categories and the appropriate management in endemic goiter regions.

Malignancy risk stratification and FNA recommendations for thyroid nodules: A comparison of ACR TI-RADS, AACE/ACE/AME and ATA guidelines

OBJECTIVE

To compare diagnostic performance and malignancy risk stratification among guidelines set forth by the American Thyroid Association (ATA) in 2015, the American Association of Clinical Endocrinologists (AACE), the American College of Endocrinology (ACE) and the Association Medici Endocrinologi (AME) in 2016, and the American College of Radiology (ACR) in 2017.

METHODS

The retrospective study was approved by the hospital ethics committee, and the informed consent requirement was waived. From October 2015 to March 2016, a total of 230 patients with 230 consecutive thyroid nodules were enrolled in this study. Each nodule was classified by one junior and one senior radiologist separately according to ACR TI-RADS, AACE/ACE/AME and ATA guidelines. The malignancy diagnostic performance and the number of FNA recommendations were pairwise compared among three guidelines using chi-square tests.

RESULTS

Of the 230 thyroid nodules, 137 were malignant, and 93 were benign. However, 19.6% of the nodules (45 of 230) did not match any pattern using the ATA guidelines but with a high risk of malignancy (68.9%). The ACR TI-RADS derived the highest diagnostic performance, from both junior radiologist (AUC 0.815) and senior radiologist (AUC 0.864). The ACR guidelines also showed the greatest level of sensitivity (junior: 86.1%, senior: 94.9%), compared with AACE/ACE/AME and ATA guidelines. The number of thyroid nodules recommended to fine-needle aspiration (FNA) was the lowest (37.8%, 40.4%) by ACR TI-RADS, and meanwhile, the malignant detection rate within these nodules was highest (64.4%, 68.8%).

CONCLUSIONS

The ACR guidelines present a higher level of diagnostic indicators and may offer a meaningful reduction in FNA recommendations with a higher malignancy detection rate.

Conventional ultrasound characteristics, TI-RADS category and shear wave speed measurement between follicular adenoma and follicular thyroid carcinoma

The purpose of the study was to explore the differences of conventional ultrasound characteristics, thyroid imaging reporting and data system (TI-RADS) category and shear wave speed (SWS) measurement between follicular adenoma (FA) and follicular thyroid carcinoma (FTC). Twenty-eight FTCs and 67 FAs proven by surgery were retrospectively included for analysis. Conventional ultrasound and point-shear wave elastography (p-SWE) were performed in all of the included patients. The ultrasound features, American Thyroid Association (ATA) TI-RADS category and American College of Radiology (ACR) TI-RADS category, SWS measurement were compared between the two groups. Receiver operating characteristic (ROC) curve was performed and area under ROC curve (AUC) was obtained for significant features. There were no statistical differences in mean age (46.9±15.7years vs. 48.6±13.6years, P = 0.639), gender (9 males, 32.1% vs. 18 males, 29.0%, P = 0.766) and mean diameter (28.3±16.2 mm vs. 33.8±11.9 mm, P = 0.077) between FTCs and FAs. Hypoechogenicity, lobulated or irregular margin, macrocalcification were more common in FTCs than FAs (all P < 0.05). Mean SWS of FTCs (2.29±0.64 m/s) was slightly higher than that of FAs (1.94±0.68 m/s) (P = 0.023). The AUCs were 0.655, 0.744, and 0.744 with the cut-off SWS≥1.89 m/s, ACR TI-RADS category 4 and intermediate suspicion of ATA TI-RADS category. The sensitivity and AUC were 82.1% and 0.812 with combined ultrasound features of hypoechogenicity, lobulated or irregular margin and macrocalcification. In Conclusion, SWS measurement and TI-RADS categories were useful for the identification of FTCs from FAs.

Comparison between Sonographic Features and Fine Needle Aspiration Cytology with Histopathology in the Diagnosis of Solitary Thyroid Nodule

BACKGROUND

High resolution ultrasonography (USG) is the first-line investigation in evaluation of euthyroid nodules. Thyroid imaging reporting and data system (TIRADS) is an USG-based risk stratification system for classifying thyroid nodules. Subjects with high-risk category of TIRADS undergo fine needle aspiration cytology (FNAC) and FNAC findings are reported according to Bethesda classification. Bethesda categories are used for determining risk of malignancy. Data regarding sonographic classification of thyroid nodule and its cytological association with respect to final histopathological diagnosis remains scarcely available in India.

AIMS AND OBJECTIVE

The study evaluated euthyroid nodules for risk of malignancy and compared sonographic features and FNAC (Bethesda classification) findings with histopathology of excised samples.

MATERIAL AND METHODS

This was a single-center observational study on 137 consecutive subjects of solitary euthyroid nodule. All subjects underwent USG according to TIRADS and FNAC where applicable. Surgical biopsy report was used as a gold standard.

RESULTS

The sensitivity, specificity, accuracy, positive predictive and negative predictive value of FNAC were 80%, 90%, 85%, 86%, and 86.6% and TIRADS were 80%, 47.2% 61%, 51.3%, and 77.3%, respectively. FNAC classification was equally sensitive and more specific than TIRADS. Among individual USG parameters, micro-calcification was most sensitive (80%) and specific (86%). Irregular margin and taller-than-wider shape had a specificity of 89% and 92%, respectively. 3 patients (14.28%) with benign cytology and suspicious USG features (specifically TIRADS 4 & 5) undergoing surgery had malignancy in final HPE.

CONCLUSIONS

USG and FNAC are equally sensitive in diagnosing malignant thyroid nodule but FNA is more specific (90%). It's a minimally invasive method which can be used to distinguish malignant from benign lesions with a high degree of accuracy (85%). In patient having high risk feature on USG, a benign cytology needs to be repeat FNAC and they should undergo surgical biopsy for confirmation.

The Diagnostic Role of Computed Tomography for ACR TI-RADS 4-5 Thyroid Nodules With Coarse Calcifications

Objectives: Coarse calcifications are prone to cause echo attenuation during ultrasonography (US) and hence affect the classification of benign and malignant nodules. This study aimed to investigate the diagnostic role of computed tomography (CT) for differentiating the American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS) 4–5 nodules with coarse calcifications.

Methods: CT data of 216 ACR TI-RADS 4–5 nodules with coarse calcifications confirmed by surgery and pathology in 207 patients were analyzed retrospectively. Halo sign, artifacts, and CT values (i.e., Hounsfield unit) of the nodules were determined by two radiologists. Univariate analysis and binary logistic regression were used to determine the relationship of halo sign, artifact, and CT value with benign nodules. A predictive model for benign nodules with coarse calcifications was then constructed. The receiver operating characteristic (ROC) curve was used to analyze the predictive value of halo sign, artifact, CT value, and logistic regression model.

Results: Of the 216 ACR TI-RADS 4–5 nodules with coarse calcifications, 170 were benign and 46 were malignant. There were 92 benign and 7 malignant nodules with halo sign (χ² = 22.067, P < 0.001), and 79 benign and 10 malignant nodules with artifacts (χ² = 9.140, P < 0.001). The CT values of benign and malignant nodules were 791 (543–1,025) Hu and 486 (406–670) Hu, respectively (Z = −5.394, P < 0.001). Binary logistic regression demonstrated that the halo sign, artifact, and CT value were independent predictors for benign nodules with coarse calcifications. The area under the ROC curve (AUC) of halo sign, artifact, CT value and regression model for predicting benign nodules with coarse calcifications were 0.776, 0.711, 0.784, and 0.850, respectively, and the optimal threshold of CT value was 627.5 Hu.

Conclusion: Halo sign, artifact, and CT value > 627.5 Hu were helpful for identifying ACR TI-RADS 4–5 thyroid benign nodules with coarse calcifications. The diagnostic performance of the logistic regression model was higher than that of any single indicator. Accurate identification of these indicators could identify benign nodules and reduce unnecessary surgical trauma.

Impact of image analysis and artificial intelligence in thyroid pathology, with particular reference to cytological aspects

OBJECTIVE

Thyroid pathology has great potential for automated/artificial intelligence algorithm application as the incidence of thyroid nodules is increasing and the indeterminate interpretation rate of fine-needle aspiration remains relatively high. The aim of the study is to review the published literature on automated image analysis and artificial intelligence applications to thyroid pathology with whole-slide imaging.

METHODS

Systematic search was carried out in electronic databases. Studies dealing with thyroid pathology and use of automated algorithms applied to whole-slide imaging were included. Quality of studies was assessed with a modified QUADAS-2 tool.

RESULTS

Of 919 retrieved articles, 19 were included. The main themes addressed were the comparison of automated assessment of immunohistochemical staining with manual pathologist's assessment, quantification of differences in cellular and nuclear parameters among tumour entities, and discrimination between benign and malignant nodules. Correlation coefficients with manual assessment were higher than 0.76 and diagnostic performance of automated models was comparable with an expert pathologist diagnosis. Computational difficulties were related to the large size of whole-slide images.

CONCLUSIONS

Overall, the results are promising and it is likely that, with the resolution of technical issues, the application of automated algorithms in thyroid pathology will increase and be adopted following suitable validation studies.

Hounsfield Unit Values in ACR TI-RADS 4-5 Thyroid Nodules with Coarse Calcifications: An Important Imaging Feature Helpful for Diagnosis

Purpose

The purpose of this study is to investigate the diagnostic role of Hounsfield unit (HU) values on noncontrast computed tomography (CT) for differentiating benignity from malignancy in the American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS) 4-5 nodules with coarse calcifications.

Patients and Methods

CT images of 216 ACR TI-RADS 4-5 nodules with coarse calcifications from 207 patients who underwent surgery in our hospital between 2017 and 2019 were retrospectively reviewed. The average HU values (AHUVs) and maximum HU values (MHUVs) of the nodules were measured on noncontrast CT. The distribution of AHUVs and MHUVs in benign and malignant nodules with coarse calcifications was analyzed using the Mann-Whitney test. Receiver operating characteristic (ROC) curves were used to identify the best cut-off values. Diagnostic performances were assessed according to the area under the ROC curve (AUC), sensitivity and specificity.

Results

Of the 216 ACR TI-RADS 4-5 nodules with coarse calcifications, 170 were benign and 46 were malignant. The AHUVs of benign and malignant nodules were 791 HU [interquartile range (IQR), 543-1025 HU] and 486 HU (IQR, 406-670 HU), respectively (P < 0.001). The MHUVs of benign and malignant nodules were 1084 HU (IQR, 717-1477 HU) and 677 HU (IQR, 441-986 HU), respectively (P < 0.001). The AUCs for AHUVs and MHUVs for predicting benign nodules with coarse calcifications were 0.759 and 0.732, and the cut-off values were 627.5 HU and 806.0 HU, with sensitivities of 67.6% and 68.8% and specificities of 73.9% and 67.4%, respectively. The sensitivity and specificity of the combination were 68.8% and 76.1%.

Conclusion

AHUVs and MHUVs were helpful in differentiating benignity from malignancy in ACR TI-RADS 4-5 nodules with coarse calcifications. This may provide an important basis for reducing misdiagnosis and unnecessary aspiration or surgical trauma.

Thyroid Fine-Needle Aspiration Cytology: Focusing on Adherence to Guidelines and Hospital Organization

Patient: Female, 39-year-old

Final Diagnosis: Goiter with periprocedural complication

Symptoms: None

Medication:—

Clinical Procedure: Fine-needle aspiration cytology

Specialty: Radiology

[Accuracy of two thyroid imaging, reporting and data systems for differential diagnosis of benign and malignant thyroid nodules]

OBJECTIVE

To compare the accuracy of two widely used thyroid imaging, reporting and data systems (TI-RADS), namely ACR TI-RADS and Kwak TI-RADS, in the differential diagnosis of benign and malignant thyroid nodules.

METHODS

We reviewed the data of 350 thyroid nodules with definite diagnoses by surgical histopathology (n=144, 41.14%) or fine needle aspiration (FNA) cytopathology (n=206, 58.86%). The nodules were graded using ACR TI-RADS and Kwak TI-RADS based on the ultrasound images, and the diagnostic accuracy of these two systems was evaluated by the area under the receiveroperating characteristic curve (AUC).

RESULTS

The AUCs of ACR TI-RADS and Kwak TI-RADS were both 0.879. For a differential diagnosis of the thyroid nodules, ACR TI-RADS had a diagnostic sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, Youden's index and accuracy of 77.3%, 89.1%, 83.0%, 85.1%, 7.101, 0.255, 27.848, 0.664 and 0.843, respectively, with an optimal threshold of TR5, as compared with 84.8%, 84.0%, 78.3%, 89.0%, 5.283, 0.181, 29.265, 0.688 and 0.843, respectively, of Kwak TI-RADS, which had an optimal threshold of 4c.

CONCLUSIONS

Both ACR TI-RADS and Kwak TI-RADS have good performance for differential diagnosis of thyroid nodules, but ACR TI-RADS has a higher specificity and a lower sensitivity compared with Kwak TI-RADS.

Thyroid nodules: diagnostic evaluation based on thyroid cancer risk assessment

Thyroid nodules are extremely common and can be detected by sensitive imaging in more than 60% of the general population. They are often identified in patients without symptoms who are undergoing evaluation for other medical complaints. Indiscriminate evaluation of thyroid nodules with thyroid biopsy could cause a harmful epidemic of diagnoses of thyroid cancer, but inadequate selection of thyroid nodules for biopsy can lead to missed diagnoses of clinically relevant thyroid cancer. Recent clinical guidelines advocate a more conservative approach in the evaluation of thyroid nodules based on risk assessment for thyroid cancer, as determined by clinical and ultrasound features to guide the need for biopsy. Moreover, newer evidence suggests that for patients with indeterminate thyroid biopsy results, a combined assessment including the initial ultrasound risk stratification or other ancillary testing (molecular markers, second opinion on thyroid cytology) can further clarify the risk of thyroid cancer and the management strategies. This review summarizes the clinical importance of adequate evaluation of thyroid nodules, focuses on the clinical evidence for diagnostic tests that can clarify the risk of thyroid cancer, and highlights the importance of considering the patient's values and preferences when deciding on management strategies in the setting of uncertainty about the risk of thyroid cancer.

Management of Thyroid Nodules in Deceased Donors With Comparison Between Fine Needle Aspiration and Intraoperative Frozen Section in the Setting of Transplantation

INTRODUCTION

Newly discovered thyroid nodules in deceased donors are investigated to rule out cancer that can be transmitted, but there are no established protocols. The aim of the study was to compare fine needle aspiration versus intraoperative frozen section in the donor management with limited time.

METHODS

Data were extracted only from the records of Italian second opinion consultation service in the years 2016 to 2017 and included donor details, pathology diagnoses, complications, transmission risk profile, and impact on transplantation.

RESULTS

Among 31 deceased donors with thyroid nodules, we documented 4 with a clinical history of cancer and 27 with a newly discovered nodule. The latter was evaluated by thyroidectomy with frozen section in 22 and fine needle aspiration in 5. Among all donors, 7 had papillary thyroid carcinoma with negligible transmission risk, whereas 8 with unacceptable risk. Two donors presented major bleeding after thyroidectomy, with organ discard in 1 case. Transplantation was delayed in 4 cases that were evaluated with frozen section.

DISCUSSION

There was no uniform approach for the investigation of thyroid nodules. Our results showed that fine needle aspiration was more accurate and useful than frozen section. Fine needle aspiration had minor economic impact and a far less rate of bleeding/hemodynamic complications, potentially delaying and compromising organ recovery. Our results suggested considering fine needle aspiration as a first step in the evaluation of thyroid nodules in donors.

Assessment of The Bethesda System for Reporting Thyroid Cytopathology

OBJECTIVES

Long-term follow-up is important for determining performance characteristics of thyroid fine-needle aspiration (FNA).

METHODS

Histologic or 3 or more years of clinical follow-up was used to calculate performance characteristics of thyroid FNA before and after implementation of The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC). The impact of noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) classification was also investigated.

RESULTS

Follow-up was obtained for 1,277/1,134 and 1,616/1,393 aspirates/patients (median clinical follow-up, 9.9 and 4.4 years, pre- and post-TBSRTC, respectively). Nondiagnostic, suspicious for follicular neoplasm, and suspicious for malignancy (SFM) diagnoses decreased and benign diagnoses increased post-TBSRTC, while atypical rate remained less than 1%. Negative predictive value for benign nodules and positive predictive value (PPV) for SFM increased significantly. Eleven nodules were reclassified as NIFTP, slightly decreasing PPV/risk of malignancy (ROM).

CONCLUSIONS

Appropriate ROM for thyroid FNA can be achieved through application of TBSRTC terminology with minimal use of atypical category.

Clinical Study of the Prediction of Malignancy in Thyroid Nodules: Modified Score versus 2017 American College of Radiology's Thyroid Imaging Reporting and Data System Ultrasound Lexicon

The clinical importance of thyroid nodules rests with the need to exclude thyroid cancer. In the present study, we developed a modified Thyroid Imaging Reporting and Data System (TI-RADS) score using gray-scale ultrasound, contrast-enhanced ultrasound (CEUS) and shear-wave elastography (SWE) images to predict malignancy of thyroid nodules and compared this modified score system with the subjective scoring criteria based on the Thyroid Imaging Reporting and Data System (TI-RADS, 2017 edition). The results revealed that by using SWE and CEUS (enhanced pattern) to downgrade TI-RADS category 4 and 5 nodules, the malignancy rate for TI-RADS category 4 and 5 nodules increased from 47.6% with American College of Radiology (ACR) TI-RADS assessment alone to 49.4% with ACR TI-RADS combined with shear wave elastography (SWE) and CEUS (enhanced pattern). Likewise, by using the modified TI-RADS to adjust TI-RADS category 3 nodules, the malignancy rate for TI-RADS category 3 nodules increased from 13.9%-20.0%. The discriminating power for detection of malignancy of the variable score 2 (ACR TI-RADS + SWE + CEUS), with an area under the curve (AUC) of 0.899 (95% confidence interval [CI]: 86.1%-93.6%), was higher than that of score 1 (ACR TI-RADS), with an AUC of 0.862 (95% CI: 81.9%-90.6%; p > 0.05). With a point 4.5 as the optimal cutoff value, a score of 1 predicted malignancy with an accuracy of 75.6%, sensitivity of 85.0% and specificity of 71.6%. However, with a point 5.5 as the optimal cutoff value, a score of 2 predicted malignancy with an accuracy of 84.9%, sensitivity of 81.0% and specificity of 86.6%. The modified TI-RADS based on ACR TI-RADS + SWE + CEUS (enhanced pattern) could contribute to a reduction in the number of biopsies performed on benign nodules and the implementation of consistent follow-up in clinical practice.

Peripheral Thyroid Nodule Calcifications on Sonography: Evaluation of Malignant Potential

OBJECTIVE. The purpose of this study is to assess the association of thyroid cancer with sonographic features of peripheral calcifications. MATERIALS AND METHODS. We retrospectively reviewed patients who had a total of 97 thyroid nodules with peripheral calcifications who underwent ultrasound-guided fine-needle aspiration from 2008 to 2018. Three board-certified radiologists evaluated the nodules for features of peripheral calcifications: the percentage of the nodule involved by peripheral calcifications, whether the calcifications were continuous or discontinuous, the visibility of internal components of the nodule, and the presence of extrusion of soft tissue beyond the calcifications. The correlation of peripheral calcification parameters with the rate of thyroid nodule malignancy was evaluated. In addition, the interobserver agreement between readers was assessed with Cohen kappa coefficient. RESULTS. Of the 97 nodules with peripheral calcifications, 27% (n = 26) were found to be malignant on biopsy. The continuity of peripheral calcifications, visibility of internal components, and extrusion of soft tissue beyond the calcification rim showed no significant association with benign or malignant nodules. Readers had good agreement on peripheral calcification continuity (κ = 0.63; 95% CI, 0.53-0.73) and moderate agreement on internal component visibility (κ = 0.43; 95% CI, 0.35-0.51) and percentage of the nodule involved by rim calcifications (κ = 0.52; 95% CI, 0.44-0.59). There was fair agreement for extranodular soft-tissue extrusion (κ = 0.32, 95% CI, 0.24-0.39). CONCLUSION. Peripheral rim calcifications are highly associated with malignancy. However, specific peripheral rim calcification features do not aid in distinguishing benign from malignant nodules, which may in part be caused by high interobserver variability.

Comparison of Different Risk-Stratification Systems for the Diagnosis of Benign and Malignant Thyroid Nodules

Introduction: To compare the efficacy of four different ultrasound-based risk-stratification systems in assessing the malignancy risk of thyroid nodules in the Chinese population. Methods: We retrospectively reviewed the digital ultrasound images of 1,568 patients (1,612 thyroid nodules) who underwent surgery in our hospital between January 2012 and December 2017. All thyroid nodules were pathologically identified as malignant or benign. We evaluated the following ultrasound characteristics: size, location, composition, echogenicity, shape, margins, calcification or echogenic foci, and extrathyroidal extension. Each nodule was categorized using four risk-stratification systems: the American Thyroid Association (ATA) classification, the Thyroid Imaging, Reporting, and Data System (TIRADS) of the American College of Radiology (ACR-TIRADS), the European Thyroid Association TIRADS (EU-TIRADS), and the TIRADS developed by Kwak et al. (Kwak-TIRADS). The diagnostic performance of each risk-stratification system relative to the pathological results was analyzed. We used receiver operating characteristic curves to identify cutoff values that yielded optimal sensitivity (SEN), specificity (SPE), positive predictive value (PPV), negative predictive value (NPV), and accuracy (ACC). Results: Of the 1,612 nodules, 839 (52.0%) were benign, and 773 (48.0%) were malignant. The AUCs of the ACR-TIRADS, EU-TIRADS, Kwak-TIRADS, and ATA classification were 0.879, 0.872, 0.896, and 0.869, respectively. The Kwak-TIRADS had the best SEN, NPV, ACC, and AUC, while the ACR-TIRADS had the best SPE and PPV. Conclusion: All four risk-stratification systems had good diagnostic performances (AUCs > 86%). Considering its high SEN, NPV, ACC, and AUC, we believe that the Kwak-TIRADS may be the more effective risk-stratification system in the Chinese population.

Ultrasound-guided fine-needle aspiration biopsy of thyroid nodules <10 mm in the maximum diameter: does size matter?

Objective

Ultrasound-guided fine-needle aspiration biopsy (US-FNAB) is a safe and effective method of screening malignant thyroid nodules such as papillary thyroid carcinoma. However, not much data are available regarding the diagnostic efficacy of US-FNAB for papillary thyroid microcarcinoma (≤10 mm in diameter). We aim to compare the diagnostic efficacy of US-FNAB on thyroid nodules between two groups divided by a diameter of 10 mm by correlating the cytological results of US-FNAB with the histopathologic diagnoses in selected patients.

Patients and methods

Eight hundred twenty-two thyroid nodules (Group A: diameter ≤10 mm, n=620; Group B: diameter >10 mm, n=202) from 797 patients treated between March 2014 and June 2017 were retrospectively evaluated. Only nodules with Thyroid Imaging Reporting and Data System (TIRADS) categories 4–6 were enrolled and sampled by US-FNAB, followed by surgical resection.

Results

According to The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) diagnostic categories, 94 thyroid nodules were classified as I, III and IV, and were excluded from the analysis. The resultant 728 thyroid nodules from 721 patients were analyzed. The malignant tendency (TBSRTC V and VI) rates on US-FNAB were 88.2% and 84.6% (P=0.202) in Group A and Group B, respectively, and the malignant rates were 89.5% and 86.9% (P=0.330), respectively, on histopathology. There was a high concordance between cytology and histopathology diagnoses (kappa value =0.797), and no statistical difference in terms of US-FNAB accuracy was found between the two groups (P=0.533).

Conclusion

For thyroid nodules of TIRADS category 4–6, the diagnostic efficacy of US-FNAB is similar for thyroid nodules either smaller or greater than 10 mm in their maximum diameter.

Patients' knowledge about the outcomes of thyroid biopsy: a patient survey

PURPOSE

Fine-needle aspiration biopsy of the thyroid is an increasingly common outpatient procedure. Patients are counseled about the indications and risks of this procedure and informed consent is obtained. We aimed to assess the extent to which patients acquired necessary knowledge during this process.

METHODS

Survey study conducted in a thyroid nodule clinic at a referral center. Adult patients who had just undergone a thyroid biopsy were asked to complete a survey, including eight questions regarding the indications and potential outcomes of thyroid biopsy. The main outcome of the study was to assess the patients' knowledge based on the response to each individual survey question.

RESULTS

Two-hundred and ninety-seven patients were eligible, of which 196 (66%) completed the survey: most were women (76%), had adequate reading health literacy (95%) and a mean age of 58 years. Although 86% of patients correctly identified evaluation for thyroid cancer as the main indication for their biopsy, 56% were not aware of the likelihood of this diagnosis. Almost all (>90%) of respondents knew that results could be benign or malignant; fewer were aware of non-diagnostic (71%) or indeterminate (68%) outcomes, or of the need for additional diagnostic testing after the biopsy (33%).

CONCLUSIONS

After undergoing thyroid biopsy, a high proportion of well-educated patients remained unaware of their risk for thyroid cancer, potential outcomes, and downstream consequences of their biopsy. This quality gap raises the possibility that informed consent procedures that meet legal standards may leave patients undergoing thyroid biopsy paradoxically uninformed.

Ethanol Ablation for the Treatment of Cystic and Predominantly Cystic Thyroid Nodules

OBJECTIVE

To determine the efficacy and safety of percutaneous ethanol injection (PEI) for the treatment of symptomatic cystic thyroid nodules.

PATIENTS AND METHODS

Retrospective analysis of patients with benign cystic thyroid nodules treated with PEI from February 1, 2000, through October 31, 2016. The main outcomes were efficacy, defined as symptom relief or reduction in nodule volume of 50% or more, and safety, defined as no or minor adverse events.

RESULTS

Twenty patients had PEI. Mean age at the time of PEI was 50 years, and 13 (65%) were women; all patients were euthyroid. Twelve patients (60%) had complex cystic thyroid nodules (>50% cystic component), with the rest being purely cystic. The median largest diameter of the thyroid cyst was 4.5 cm (interquartile range [IQR], 3.2-5.3 cm; range, 2.3-8.0 cm); the median volume pre-PEI was 19.6 mL (IQR, 10.4-48.5 mL; range, 2.8-118.1 mL). The median amount of cystic fluid drained before PEI was 13.5 mL (IQR, 6.8-32.3 mL), and the median amount of ethanol administered was 3 mL (IQR, 2-5 mL; range, 0.5-20 mL). After median follow-up of 2 years, 17 of 19 patients (89%) were asymptomatic. Of 10 patients with available imaging on follow-up, 7 (70%) had a 50% or greater reduction in nodule volume (median volume decrease, 75.64% [IQR, 41.40%-91.99%]). Adverse effects occurred in 4 patients (20%) and were mild and temporary (slight pain, vagal reaction, and bleeding into the cyst).

CONCLUSION

Percutaneous ethanol injection seems to be a safe and effective alternative to surgical resection for patients with purely or predominantly cystic thyroid nodules and compressive symptoms who decline surgery or are not good surgical candidates.

ACR Thyroid Imaging, Reporting and Data System (TI-RADS): White Paper of the ACR TI-RADS Committee

classification that is widely used in breast imaging, their authors chose to apply the acronym TI-RADS, for Thyroid Imaging, Reporting and Data System. In 2012, the ACR convened committees to (1) provide recommendations for reporting incidental thyroid nodules, (2) develop a set of standard terms (lexicon) for ultrasound reporting, and (3) propose a TI-RADS on the basis of the lexicon. The committees published the results of the first two efforts in 2015. In this article, the authors present the ACR TI-RADS Committee's recommendations, which provide guidance regarding management of thyroid nodules on the basis of their ultrasound appearance. The authors also describe the committee's future directions.

Thyroid nodule update on diagnosis and management

Thyroid nodules are common. The clinical importance of thyroid nodules is related to excluding malignancy (4.0 to 6.5% of all thyroid nodules), evaluate their functional status and assess for the presence of pressure symptoms. Incidental thyroid nodules are being diagnosed with increasing frequency in the recent years with the use of newer and highly sensitive imaging techniques. The high prevalence of thyroid nodules necessitates that the clinicians use evidence-based approaches for their assessment and management. New molecular tests have been developed to help with evaluation of malignancy in thyroid nodules. This review addresses advances in thyroid nodule evaluation, and their management considering the current guidelines and supporting evidence.

Fine needle aspiration cytology guided by ultrasound in the diagnosis of subcentimetre thyroid nodules

Background

This study aimed to investigate the value of fine needle aspiration biopsy (FNAB) under ultrasound guidance in diagnosis of thyroid nodules. In a retrospective analysis of FNAB in 1050 cases of patients with 1100 nodules, patients were divided according to the maximum diameter of their nodules into two groups: >1.0 and ≤1.0 cm. The ultrasound-guided FNAB cytology results were compared between two groups.

Results

Ultrasound findings showed that among 1100 thyroid nodules, 547 were highly suspicious, 358 were moderately, 175 were low, and 19 were very low. Cytology results showed papillary carcinomas in 453, possible papillary cancer in 126 cases, follicular tumors in 26, suspicious follicular tumors in 6, atypical cells in 7, nodular goiter in 289, colloid in 13, chronic lymphocytic thyroiditis in 175, and undiagnosed specimen in 5. Ultrasound diagnosis of thyroid nodules had an overall sensitivity of 86.0 %, and a specificity of 81.9 %. In nodules larger than 1.0 cm, the sensitivity was 92.8 %, and the specificity 92.3 %. In nodules ≤1.0 cm, the sensitivity was 82.4 %, and the specificity was 81.7 %.

Conclusions

Patients with highly suspicious thyroid nodules on ultrasonography, regardless of nodule sizes, should receive ultrasound-guided FNAB to confirm their natures and direct clinical managements.