Characterization of thyroid nodules using the proposed thyroid imaging reporting and data system (TI-RADS)

American Thyroid Association and Thyroid Imaging Reporting and Data System developed by the American College of Radiology: which one is better at predicting malignancy risk?

OBJECTIVE

The aim of this study was to compare the capacity of American Thyroid Association and Thyroid Imaging Reporting and Data System developed by the American College of Radiology in predicting malignancy risk of thyroid nodules and to verify which one is better at avoiding unnecessary fine needle aspiration.

METHODS

This was a cross-sectional study with 565 thyroid nodules, followed at a tertiary care hospital, in an iodine-replete area. Those were classified as American Thyroid Association and Thyroid Imaging Reporting and Data System developed by the American College of Radiology systems and stratified according to the Bethesda classification of fine needle aspiration. The values of sensibility, specificity, positive predictive value, and negative predictive value accuracy were calculated. Also, the percentage of unnecessary biopsies was presented.

RESULTS

The mean age of the individuals was 58.2±13.5 [26-90] years for benign nodules and 41.7±15.6 [23-66] years for malignant nodules (p=0.002). Regarding gender, 92.6% (n=150) of the individuals with benign nodules and 85.7% (n=06) with malignant nodules were females (p=0.601). For American Thyroid Association, 90.9% of sensibility, 51.4% of specificity, 52.6% of accuracy, 10.2% of positive predictive value, and 98.9% of negative predictive value were found. For Thyroid Imaging Reporting and Data System developed by the American College of Radiology, 90.9% of sensibility, 49.7% of specificity, 52.1% of accuracy, 9.9% of positive predictive value, and 98.9% of negative predictive value were found. .Notably, 12.3% of unnecessary fine needle aspiration were found in American Thyroid Association and 44.4% were found in Thyroid Imaging Reporting and Data System developed by the American College of Radiology.

CONCLUSION

Both Thyroid Imaging Reporting and Data System developed by the American College of Radiology and American Thyroid Association are able to predict the malignancy risk of thyroid nodules. Thyroid Imaging Reporting and Data System developed by the American College of Radiology was better at avoiding unnecessary fine needle aspiration.

Analysis of Thyroid Imaging Reporting and Data System Criteria and Its Correlation With the Pathological Results

Introduction Thyroid nodules are frequently encountered and may be discovered roughly in around 4-8% of individuals by clinical palpation. Aim The present study aims to analyze the Thyroid Imaging Reporting and Data Systems (TIRADS) classification and assess the validity of each criterion in predicting malignancy. Methods A prospective observational study was conducted at Sri Ramachandra Institute of Higher Education and Research from June 2020 to October 2021. Fifty patients who presented to the outpatient clinic with thyroid swelling got an ultrasound (USG) neck performed followed by either fine-needle aspiration cytology (FNAC) or thyroidectomy. They were included in the study and informed consent was obtained from all patients. Results Among 50 patients considered for the study, 36 were females. The mean age for malignant patients is 46 years with a standard deviation (SD) of 15, and for benign lesions is 47 years with an SD of 1. Most of the patients were TIRADS 4, which has a 56.2% risk of malignancy. The pathological results show a significant difference in ACR (American College of Radiology) TIRADS and echogenic foci between FNAC. The present study's solid composition showed a sensitivity of 25% and specificity of 75%, with an odds ratio of 0.90 in picking up malignant nodules. The shape of a nodule taller than wider, a malignant feature, showed a specificity of 92.3%. Punctate echogenic foci showed a sensitivity of 50% and specificity of 76.9% with a statistical significance of p-value 0.048. Conclusion TIRADS scoring avoids unessential invasive techniques for lower TIRADS scores. Certain criteria are more specific in recognizing malignant nodules. Proportional priority shall be given to certain criteria over others, and not all criteria should be considered.

Inter-Rater Reliability of Thyroid Ultrasound Risk Criteria: A Systematic Review and Meta-Analysis

OBJECTIVE

The most commonly employed diagnostic criteria for identifying thyroid nodules include Thyroid Imaging and Reporting Data System (TI-RADS) and American Thyroid Association (ATA) guidelines. The purpose of this systematic review and meta-analysis is to determine the inter-rater reliability of thyroid ultrasound criteria.

METHODS

We performed a library search of MEDLINE (Ovid), EMBASE (Ovid), and Web of Science for full-text articles published from January 2005 to June 2022. We included full-text primary research articles that used TI-RADS and/or ATA guidelines to evaluate thyroid nodules in adults. These included studies must have calculated inter-rater reliability using any validated metric. The Quality Appraisal for Reliability Studies (QAREL) was used to assess study quality. We planned for a random-effects meta-analysis, in addition to covariate and publication bias analyses. This study was performed in accordance with Preferred Reporting Items for a Systematic Review and Meta-analysis guidelines and registered prior to conduction (International prospective register of systematic reviews-PROSPERO: CRD42021275072).

RESULTS

Of the 951 articles identified via the database search, 35 met eligibility criteria. All studies were observational. The most commonly utilized criteria were ACR Thyroid Imaging and Reporting Data System (TI-RADS) and/or ATA criteria, while the majority of studies employed Κ statistics. For ACR TI-RADS, the pooled Κ was 0.51 (95% confidence interval [CI]: 0.42, 0.57; n = 7) while for ATA, the pooled Κ was 0.52 (95% CI: 0.37, 0.67; n = 3). Due to the small number of studies, covariate or publication bias analyses were not performed.

CONCLUSION

Ultrasound criteria demonstrate moderate inter-rater reliability, but these findings are impacted by poor study quality and a lack of standardization. Laryngoscope, 133:485-493, 2023.

Personalizing Surveillance in Head and Neck Cancer

Head and neck squamous cell carcinoma (HNSCC) encompasses a spectrum of heterogeneous diseases originating in the oral cavity, pharynx, and larynx. Within the United States, head and neck cancer (HNC) accounts for 66,470 new cases, or 3% of all malignancies, annually.¹ The incidence of HNC is rising, largely driven by increases in oropharyngeal cancer.^2-4 Recent molecular and clinical advancements, particularly with regard to molecular and tumor biology, reflect the heterogeneity of the subsites contained within the head and neck. Despite this, existing guidelines for post-treatment surveillance remain broad without much consideration given to different anatomic subsites and etiologic factors (such as human papillomavirus [HPV] status or tobacco exposure).⁵ Surveillance incorporating the physical examination, imaging, and emerging molecular biomarkers is an essential part of care for patients treated for HNC and allows for the detection of locoregional recurrence, distant metastases, and second primary malignancies aiming for better functional and survival outcomes. Additionally, it allows for evaluation and management of post-treatment complications.

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

OBJECTIVES

To evaluate the diagnostic efficacy of a modified thyroid imaging reporting and data system (TI-RADS) in combination with contrast-enhanced ultrasound (CEUS) for differentiating between benign and malignant thyroid nodules and to assess inter-observer concordance between different observers.

METHODS

This study included 3353 patients who underwent thyroid ultrasound (US) and CEUS in ten multi-centers between September 2018 and March 2020. Based on a modified TI-RADS classification using the CEUS enhancement pattern of thyroid lesions, ten radiologists analyzed all US and CEUS examinations independently and assigned a TI-RADS category to each thyroid nodule. Pathology was the reference standard for determining the diagnostic performance (accuracy (ACC), sensitivity (SEN), specificity (SPN), positive predictive value (PPV), and negative predictive value (NPV)) of the modified TI-RADS for predicting malignant thyroid nodules. The risk of malignancy was stratified for each TI-RADS category-based on the total number of benign and malignant lesions in that category. ROC curve was used to determine the cut-off value and the area under the curve (AUC). Cohen's Kappa statistic was applied to assess the inter-observer agreement of each sonological feature and TI-RADS category for thyroid nodules.

RESULTS

The calculated malignancy risk in the modified TI-RADS categories 5, 4b, 4a, 3 and 2 nodules was 95.4%, 86.0%, 12.0%, 4.1% and 0%, respectively. The malignancy risk for the five categories was in agreement with the suggested malignancy risk. The ROC curve showed that the AUC under the ROC curve was 0.936, and the cutoff value of the modified TI-RADS classification was >TI-RADS 4a, whose SEN, ACC, PPV, NPV and SPN were 93.6%, 91.9%, 90.4%, 93.7% and 88.5% respectively. The Kappa value for taller than wide, microcalcification, marked hypoechoic, solid composition, irregular margins and enhancement pattern of CEUS was 0.94, 0.93, 0.75, 0.89, 0.86 and 0.81, respectively. There was also good agreement between the observers with regards to the modified TI-RADS classification, the Kappa value was 0.80.

CONCLUSIONS

The actual risk of malignancy according to the modified TI-RADS concurred with the suggested risk of malignancy. Inter-observer agreement for the modified TI-RADS category was good, thus suggesting that this classification was very suitable for clinical application.

Impact of completion thyroidectomy on postoperative recovery in patients with differentiated thyroid cancer

While an increasing number of patients now undergo lobectomy for low-risk differentiated thyroid cancer, a subset of patients require completion thyroidectomy to facilitate radioactive iodine therapy. Completion thyroidectomy is generally as safe as the initial operation, but a previous study showed that a longer hospitalization is required for completion thyroidectomy. In this study, we reviewed 61 consecutive patients who had been treated with an initial lobectomy and subsequent completion thyroidectomy at our institution from 2012 to 2021. We detected a changepoint in 2016 for the proportion of patients who were treated with a thyroid lobectomy (Pettitt's test P = 0.049). The rate of completion thyroidectomy remained stable throughout the study period. There was no difference in operating time, intraoperative blood loss, perioperative drop in calcium levels, and postoperative hospital stay between surgeries. The patients reported higher pain scores on the day of operation (P = 0.007) and the postoperative day 1 (P = 0.022). Occult papillary microcarcinomas were identified in the contralateral thyroid lobe in 13 (21%) patients. Multifocality was the only predictor for residual malignancy in multivariate regression. In conclusion, patients with differentiated thyroid cancer experienced more pain in the immediate postoperative period following completion thyroidectomy. Hospital stays do not change with appropriate opioid-free pain control.

A Local and Global Feature Disentangled Network: Toward Classification of Benign-Malignant Thyroid Nodules From Ultrasound Image

Thyroid nodules are one of the most common nodular lesions. The incidence of thyroid cancer has increased rapidly in the past three decades and is one of the cancers with the highest incidence. As a non-invasive imaging modality, ultrasonography can identify benign and malignant thyroid nodules, and it can be used for large-scale screening. In this study, inspired by the domain knowledge of sonographers when diagnosing ultrasound images, a local and global feature disentangled network (LoGo-Net) is proposed to classify benign and malignant thyroid nodules. This model imitates the dual-pathway structure of human vision and establishes a new feature extraction method to improve the recognition performance of nodules. We use the tissue-anatomy disentangled (TAD) block to connect the dual pathways, which decouples the cues of local and global features based on the self-attention mechanism. To verify the effectiveness of the model, we constructed a large-scale dataset and conducted extensive experiments. The results show that our method achieves an accuracy of 89.33%, which has the potential to be used in the clinical practice of doctors, including early cancer screening procedures in remote or resource-poor areas.

Inter-reader agreement of the Prostate Imaging Quality (PI-QUAL) score: A bicentric study

PURPOSE

To investigate the inter-reader agreement of the Prostate imaging quality (PI-QUAL) for multiparametric magnetic resonance imaging (mpMRI).

METHODS

We included 66 men who underwent 1.5 T mpMRI in June 2020-July 2020 in center 1, with no exclusion criteria. mpMRI included multiplanar T2-weighted imaging (T2WI), Diffusion-weighted imaging (DWI), and dynamic contrast-enhanced imaging (DCE). Two readers from center 2 (experience <1000 to >1500 examinations), blinded to clinical history but not to acquisition parameters, independently assessed PI-QUAL qualitative/anatomical items of each mpMRI sequence, final PI-QUAL score (1-5), and the Prostate imaging reporting and data system version 2.1 (PI-RADSv2.1) category of the index lesion. Cohen's kappa statistics (k) or prevalence-adjusted-bias-adjusted kappa (PABAK) were used to calculate the inter-reader agreement in assessing the PI-QUAL (1-to-5 scale and 1-2 versus 3 versus 4-5), the diagnostic quality of each mpMRI sequence, qualitative/anatomical items, and PI-RADSv2.1 category.

RESULTS

The inter-reader agreement for PI-QUAL category was moderate upon 1-5 scale (k = 0.55; 95%CI 0.39-0.71) or 1-3 scale (k = 0.51; 95%CI 0.29-0.72), with 90.9% examinations categorized PI-QUAL ≥ 3 by readers. The agreement in assessing a sequence as diagnostic was higher for T2WI (k = 0.76) than DCE (PABAK = 0.61) and DWI (k = 0.46), ranging moderate-to-substantial for most of the items. Readers provided comparable PI-RADSv2.1 categorization (k = 0.88 [excellent agreement]; 95%CI 0.81-0.96), with most PI-RADSv2.1 ≥ 3 assignments found in PI-QUAL ≥ 3 examinations (43/46 by reader 1, and 47/47 by reader 2).

CONCLUSIONS

The reproducibility of PI-QUAL was moderate. Higher PI-QUAL scores were associated with excellent inter-reader agreement for PI-RADSv2.1 categorization.

Diagnostic grading of parotid lesions by conventional ultrasound: a pilot study

OBJECTIVES

To provide a graded diagnosis of benign and malignant lesions in the parotid gland by conventional ultrasound, and thus to predict the probability of malignancy of the lesions.

METHODS

Retrospective analysis of conventional ultrasound images of 150 patients with parotid lesions by two observers. Parotid lesions were classified into seven patterns and then categorized into eight grades: Grade 0, unsatisfied illustration on ultrasound; Grade 1, normal parotid gland; Grade 2, definitively benign; Grade 3, probably benign; Grade 4, indeterminate; Grade 5, probably malignant; Grade 6, highly suggestive malignant and Grade 7, already had malignant diagnosis. Combined with the pathological results, the conventional ultrasound diagnostic grade of parotid lesions was evaluated for predicting the probability of malignancy.

RESULTS

There was excellent interobserver agreement of both readers for patterns and grades (K = 0.89 and 0.90, p < 0.01). The proportions of the malignancies in conventional ultrasound Grade 2, 3, 4, 5 and 6 according to the two readers 0 and 0, 0 and 0, 8.7% and 8.8%, 54.2 and 50%, 100 and 100%, respectively. The sensitivity, specificity and area under ROC curve(AUC) were 64.0%, 91.2%, 0.809 and 64.0%, 89.6%, 0.802, respectively, using Grade 5 of the two readers as the best grade for diagnosing benign and malignant parotid lesions.

CONCLUSION

The conventional ultrasound diagnostic grade of parotid lesions can be used to evaluate the risk of malignancy and will be helpful to improve the imaging diagnosis and clinical treatment.

Learning curve analysis of radiofrequency ablation for benign thyroid nodules

BACKGROUND

Radiofrequency ablation (RFA) has been increasingly accepted as an alternative to surgery in the treatment of symptomatic benign thyroid nodules. However, the learning curve of thyroid RFA has yet to be defined. We hypothesized a temporal relationship between proficiency of the skill and midterm volume reduction.

METHODS

Consecutive patients who underwent RFA and had at least a six-month follow-up were identified from an institutional database. The cumulative sum (CUSUM) analysis was applied to visualize the learning curve on the adjusted volume reduction rate (VRR).

RESULTS

A total of 102 nodules in 93 patients were included in the analysis. Linear regression revealed that nodule composition was the main predictor of the VRR. The composition-adjusted VRR increased with the chronological treatment order. The series was divided into three phases based on inflection points of the CUSUM analysis: the initial learning phase (case 1-20), consolidation phase (case 21-65), and proficiency phase (case 66-102). In the later phase, more solid nodules were treated, power output used by the operator was higher, and RFA treatment time was longer.

CONCLUSION

The treatment efficiency of thyroid RFA was associated with technical proficiency, suggesting the presence of a learning curve effect.

Computer-Analyzed Ultrasound Predictors of the Treatment Efficacy of Radiofrequency Ablation for Benign Thyroid Nodules

AIM

Radiofrequency ablation (RFA) is a relatively safe and efficient alternative to surgery for patients with benign thyroid nodules. We investigated predictive factors associated with volume reduction using digital imaging analysis.

METHODS

In this retrospective study, a prospectively maintained database containing the data of patients who received treatment from April 2019 to March 2020 was analyzed. Computerized analysis for quantitative measurement of echogenicity, heterogeneity, and the proportion of cystic components was performed on ultrasonographic images. The volume reduction rate (VRR) was calculated during follow-up. Treatment efficacy was defined as a volume reduction greater than 50% of baseline volume.

RESULTS

The median volume of 58 benign thyroid nodules before RFA was 22.7 mL. Of 53 nodules with sufficient follow-up, the median VRR was 46.4%, 61.5%, 63.4%, and 67.4% at 1, 3, 6, and 12 months, respectively. Overall, at one-year follow-up, treatment efficacy was achieved in 39 (74%) nodules. In a multivariate regression analysis, the proportion of cystic components and RFA treatment time were independently associated with treatment efficacy. A subgroup analysis focusing on solid nodules indicated a negative correlation between echogenicity and VRR.

CONCLUSIONS

The proportion of cystic components in thyroid nodules is the main predictor of RFA treatment efficacy. In solid nodules, higher echogenicity is associated with a lower volume reduction.

Evaluation of thyroid nodules by shear wave elastography: a review of current knowledge

PURPOSE

Shear wave elastography (SWE), as a tool for diagnosing thyroid malignancy, has gathered considerable attention during the past decade. Diverging results exist regarding the diagnostic performance of thyroid SWE.

METHODS

A comprehensive literature review of thyroid SWE was conducted using the terms "Thyroid" and "shear wave elastography" in PubMed.

RESULTS

The majority of studies found SWE promising for differentiating malignant and benign thyroid nodules on a group level, whereas results are less convincing on the individual level due to huge overlap in elasticity indices. Further, there is lack of consensus on the optimum outcome reflecting nodule elasticity and the cut-off point predicting thyroid malignancy. While heterogeneity between studies hinders a clinically meaningful meta-analysis, the results are discussed in a clinical perspective with regard to applicability in clinical practice as well as methodological advantages and pitfalls of this technology.

CONCLUSION

Technological as well as biological hindrances seem to exist for SWE to be clinically reliable in assessing benign and malignant thyroid nodules. Structural heterogeneity of thyroid nodules in combination with operator-dependent factors such as pre-compression and selection of scanning plane are likely explanations for these findings. Standardization and consensus on the SWE acquisition process applied in future studies are needed for SWE to be considered a clinically reliable diagnostic tool for detection of thyroid cancer.

Impact of high-quality ultrasound following community ultrasound on surgical planning and active surveillance in patients with thyroid cancer

OBJECTIVE

Ultrasound (US) has gained a critical role in thyroid cancer treatment planning, yet it is limited by its user-dependent nature. The aim of this study was to compare the impact of US performed by radiologists specializing in thyroid imaging (hqUS) and US performed by radiographers in the community (cUS) on treatment plans of patients diagnosed with well-differentiated thyroid malignancies.

DESIGN

Retrospective single-centre case series with chart review.

PATIENTS

Patients diagnosed with thyroid cancer during 2017-2019 that had cUS followed by hqUS pre-operative counselling were included in this retrospective analysis.

MEASUREMENTS

The main outcome was management alternations based on one of two sonographic measures: (1) extrathyroid extension (ETE); (2) The presence of central or lateral lymph nodes suspicious for metastases (LNM), which were compared with the final pathology.

RESULTS

Among those with non-recurrent tumour (n = 76), ETE was reported 22 times more by hqUS compared with cUS (28.9% vs 1.3%, P < .001). Central and lateral LNM were reported approximately 6.5 and 1.5 times more by hqUS, respectively (25.0% vs 3.9%, P < .001 and 15.8% vs., 9.2%, P = .227, respectively). Overall, hqUS altered the initial treatment plan of 35.5% of patients. In 27.6% of patients, hqUS and its subsequent surgery resulted in a change to the patients' 2015 ATA risk stratification system. In 40% of patients with microcarcinomas, hqUS findings mandated surgery according to findings that were not reported by cUS. False-positive rate was 5.2%.

CONCLUSIONS

Community US may under-diagnose important features such as ETE and LNM, leading to potential under-treatment in many patients. High-quality US of the neck should be considered in patients with differentiated thyroid carcinoma before making any treatment decisions.

Best Practices: Application of NI-RADS for Posttreatment Surveillance Imaging of Head and Neck Cancer

Imaging surveillance is an important component of posttreatment management of head and neck cancers. There is variability in the surveillance regimen used by various practitioners and institutions, with no official National Comprehensive Cancer Network guidelines for patients showing no symptoms beyond 6 months posttreatment. Moreover, imaging of the neck after treatment is a complex examination with significant interreader heterogeneity, particularly in terms of the manner in which degree of suspicion for disease recurrence is expressed. The Neck Imaging Reporting and Data System (NI-RADS) was introduced by the American College of Radiology (ACR) in 2018 as a practical guide for the interpreting radiologist. NI-RADS is a proposed interpretive framework that can be applied to any standardized or institutional surveillance imaging protocol. NI-RADS simplifies communication between radiologists and referring clinicians and provides management guidance linked to specific levels of suspicion. The ACR NI-RADS Committee also provided general best practice recommendations for imaging surveillance modality and timing in the 2018 white paper. This article will review existing literature regarding choice of modality and timeline for surveillance in treated cancer of the head and neck. NI-RADS will then be presented as an approach to imaging reporting, interpretation, and design of next steps in management.

Ultrasonic thyroid nodule detection method based on U-Net network

OBJECTIVE

Aiming at the time consuming processing of existing thyroid nodule detection and difficulty in feature extraction, U-Net-based thyroid nodule detection is proposed to perform computed aided diagnosis.

METHOD

This paper proposes a mark-guided ultrasound deep network segmentation model of thyroid nodules. By comparing with VGG19, Inception V3, DenseNet 161, segmentation accuracy, segmentation edge and network operation time, it is found that the algorithm in this paper has relative advantages.

RESULTS

U-Net network-based ultrasound thyroid nodules segmented the nodule area overlapped with the manually depicted nodule area close to 100%, the segmentation accuracy rate was as high as 0.9785, and the U-Net segmentation result was closer to the manually depicted nodule. The accuracy of U-Net segmentation of the thyroid is about 3% higher than the other three networks.

CONCLUSION

The segmentation of nodules based on U-Net proposed in this paper significantly improves the segmentation accuracy of thyroid nodules with a small training data set, and provides a comprehensive reference for clinical diagnosis and treatment.

Evaluation of the Diagnostic Performance of EU-TIRADS in Discriminating Benign from Malignant Thyroid Nodules: A Prospective Study in One Referral Center

BACKGROUND

Several thyroid societies have endorsed ultrasound (US) malignancy risk stratification systems for thyroid nodules and the recently released European Thyroid Imaging Reporting and Data System (EU-TIRADS) needs large prospective studies for validation.

OBJECTIVE

The purpose of our study was to evaluate the performance of EU-TIRADS in identifying thyroid nodules for fine-needle aspiration biopsy (FNAB) and its ability to reduce the number of unnecessary biopsies.

METHODS

This was a single-center prospective study. From August 2017 to September 2018, 783 consecutive patients with 1,000 thyroid nodules underwent US examination and US-guided FNAB. A total of 741 patients (median age 50 years; range, 15-87 years; 649 females, 92 males) with 942 nodules (median largest diameter 14 mm; range, 4-96 mm) met the following inclusion criteria: (1) nodules with benign or malignant cytology - categories II and VI of the Bethesda System for Reporting Thyroid Cytopathology (BSRTC); (2) nodules with non-diagnostic and indeterminate cytology (BSRTC I, BSRTC III, and BSRTC IV), or suspicious for malignancy (BSRTC V), if postoperative histology was present; (3) nodules classified as BSRTC I and BSRTC III with a repeat FNAB and conclusive cytology.

RESULTS

Of 942 nodules, 839 (89.1%) were benign and 103 (10.9%) were malignant. Nodules were classified as follows: EU-TIRADS 2 - 4.8%, EU-TIRADS 3 - 37.4%, EU-TIRADS 4 - 25.2%, and EU-TIRADS 5 - 32.6%. The malignancy rate in categories 2 to 5 was 0, 0, 3.8, and 30.6%, respectively. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of EU-TIRADS with a cut-off set at category 5 were 91.3, 74.6, 30.6, 98.6, and 76.4%, respectively. Diagnostic performance other than sensitivity and NPV was superior in nodules ≥10 mm. FNAB number would be reduced by 53.4% if FNAB criteria were strictly applied. When the indication for FNAB was applied as test positivity, the estimated sensitivity, specificity, PPV, and NPV of EU-TIRADS were 69.9, 56.3, 16.4, and 93.8%, respectively.

CONCLUSION

EU-TIRADS provides effective malignancy risk stratification that can guide the selection of thyroid nodules for biopsy. The application of the guidelines criteria for FNAB in the clinical practice might reduce significantly the number of unnecessary FNAB.

Somatic Mutation Profiling of Papillary Thyroid Carcinomas by Whole-exome Sequencing and Its Relationship with Clinical Characteristics

The incidence of papillary thyroid carcinomas (PTCs) has increased rapidly during the past several decades. Until now, the mechanisms underlying the tumorigenesis of PTCs have remained largely unknown. Next-generation-sequencing (NGS) provides new ways to investigate the molecular pathogenesis of PTCs. To characterize the somatic alterations associated with PTCs, we performed whole-exome sequencing (WES) of PTCs from 23 Chinese patients. This study revealed somatic mutations in genes with relevant functions for tumorigenesis, such as BRAF, BCR, CREB3L2, DNMT1, IRS2, MSH6, and TP53. We also identified novel somatic gene alterations which may be potentially involved in PTC progression. Gene set enrichment analysis revealed that the cellular response to hormone stimulus, epigenetic modifications, such as protein/histone methylation and protein alkylation, as well as MAPK, PI3K-AKT, and FoxO/mTOR signaling pathways, were significantly altered in the PTCs studied here. Moreover, Protein-Protein Interaction (PPI) network analysis of our mutated gene selection highlighted EP300, KRAS, PTEN, and TP53 as major core genes. The correlation between gene mutations and clinicopathologic features of the PTCs defined by conventional ultrasonography (US) and contrast-enhanced ultrasonography (CEUS) were assessed. These analyses established significant associations between subgroups of mutations and respectively taller-than-wide, calcified, and peak time iso- or hypo-enhanced and metastatic PTCs. In conclusion, our study supplements the genomic landscape of PTCs and identifies new actionable target candidates and clinicopathology-associated mutations. Extension of this study to larger cohorts will help define comprehensive genomic aberrations in PTCs and validate target candidates. These new targets may open methods of individualized treatments adapted to the clinicopathologic specifics of the patients.

Development and validation of a Web-based malignancy risk-stratification system of thyroid nodules

OBJECTIVES

Previous publications on risk-stratification systems for malignant thyroid nodules were based on conventional ultrasound only. We aimed to develop a practical and simplified prediction model for categorizing the malignancy risk of thyroid nodules based on clinical data, biochemical data, conventional ultrasound and real-time elastography.

DESIGN

Retrospective cohort study.

PATIENTS

A total of 2818 patients (1890 female, mean age, 45.5 ± 13.2 years) with 2850 thyroid nodules were retrospectively evaluated between April 2011 and October 2016. 26.8% nodules were malignant.

MEASUREMENTS

We used a randomly divided sample of 80% of the nodules to perform a multivariate logistic regression analysis. Cut-points were determined to create a risk-stratification scoring system. Patients were classified as having low, moderate and high probability of malignancy according to their scores. We validated the models to the remaining 20% of the nodules. The area under the curve (AUC) was used to evaluate the discrimination ability of the systems.

RESULTS

Ten variables were selected as predictors of malignancy. The point-based scoring systems with and without elasticity score achieved similar AUCs of 0.916 (95% confidence interval [CI]: 0.885-0.948) and 0.906 (95% CI: 0.872-0.941) when validated. Malignancy risk was segmented from 0% to 100.0% and was positively associated with an increase in risk scores. We then developed a Web-based risk-stratification system of thyroid nodules (http: thynodscore.com).

CONCLUSION

A simple and reliable Web-based risk-stratification system could be practically used in stratifying the risk of malignancy in thyroid nodules.

A correlation study between thyroid imaging report and data systems and the Bethesda system for reporting thyroid cytology with surgical follow-up - an ultrasound-trained cytopathologist's experience

INTRODUCTION

Thyroid Imaging Reporting and Data Systems (TI-RADS) including a modified system (M TI-RADS) and American College Radiology (ACR) TI-RADS are introduced. Correlation studies between both TI-RADSs and The Bethesda System for Reporting Thyroid Cytology (TBSRTC) for Ultrasound-guided fine-needle aspiration (US-FNA) cases with surgical follow-up (SFU) are presented.

MATERIALS AND METHODS

Three hundred and forty six thyroid US-FNA cases performed at the US-FNA clinic of Stony Brook University Hospital by an Ultrasound-trained interventional Cytopathologist between December 1, 2014 to February 28, 2018 were reviewed. All ultrasound images from 346 cases were evaluated and assigned M TI-RADS scores based on ultrasound features present in Table 1. One hundred and fifty four cases from Dcember 1, 2014 to February 28, 2016 were assigned scores using ACR TI-RADS.TBSRTC category along with SFU data was collected and correlated with both TI-RADS scores by using Pearson's correlation coefficient (r). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall accuracy for M TI-RADS and TBSRTC were also calculated using SFU diagnosis as a gold standard. McNemar test was applied to evaluate the significance of the difference between M TI-RADS and TBSRTC.

RESULTS

Based on 346 thyroid nodules studied, the overall r-value between M TI-RADS scores and TBSRTC categories is 0.465. The r-values between Composition, Echogenicity, Shape, Margin, Echogenic foci, the summary points, and the converted TR level of ACR TI-RADS and TBSRTC are 0.145, 0.042, 0.259, 0.310, 0.405, and 0.379, respectively. Fifty (14.5%) cases have SFUs. Considering TI-RADS 5&6 and TBSRTC 5&6 as positives, and TI-RADS 2 and TBSRTC 2 as negatives, the Sensitivity, Specificity, PPV, NPV, and accuracy are 96%, 53%, 76%, 89%, 79% for TI-RADS vs 100%, 93%, 96%, 100%, 97% for TBSRTC, respectively (P = .038). The data for indeterminate cases are summarized.

CONCLUSION

Both TI-RADSs could be helpful to a moderate degree. M TI-RADS appeared to correlate to TBSRTC slightly better than that of ACR TI-RADS. TBSRTC is significantly more accurate than M TI-RADS for the majority of determined cases.

Preoperative Factors Associated with Extrathyroidal Extension in Papillary Thyroid Cancer

OBJECTIVE

Extrathyroidal extension may not be accurately recognized during thyroidectomy and can increase the risk of positive margins and even recurrence. This study aimed to investigate the preoperative factors associated with extrathyroidal extension.

METHODS

We analyzed 887 patients with papillary thyroid cancer (PTC) who underwent surgery in the period of 2005-2017. Binary logistic regression analyses and generalized additive models were used to identify associations.

RESULTS

Minimal extrathyroidal extension was present in 233 (26%) patients and advanced extrathyroidal extension was found in 60 (7%) patients. Age, BMI, and tumor size were independent predictors of all or advanced extrathyroidal extension. Among the 493 patients whose BRAF mutation status was available, age (OR = 1.025), BMI (OR = 1.091), tumor size (OR = 1.544), and BRAF V600E mutation (OR = 2.311) were independently associated with extrathyroidal extension.

CONCLUSIONS

Older age, a greater BMI, a larger tumor size, and presence of the BRAF mutation were predictive of extrathyroidal extension. These factors should be taken into consideration in decision-making before surgery is performed.

Deep Convolutional Neural Networks for Thyroid Tumor Grading using Ultrasound B-mode Images

The performances of deep convolutional neural network (DCNN) modeling and transfer learning (TF) for thyroid tumor grading using ultrasound imaging were evaluated. This retrospective study included input patient data (ultrasound B-mode image sets) assigned to the training group (115 participants) or testing group (28 participants). DCNN (ResNet50) and TF (ResNet50, ResNet101, ResNet152, VGG16, Inception V3, and DenseNet201), which trains a convolutional neural network that has been pre-trained on ImageNet, were used for image classification based on thyroid tumor grade. Supervised training was performed by using the DCNN or TF model to minimize the difference between the output data and clinical grading. The performances of the DCNN and TF models were assessed in the testing dataset with receiver operating characteristic analyses. Results showed that TF based on Resnet50 and VGG16 had better performance than DCNN (ResNet50) in differentiating thyroid tumor with areas under the receiver operating characteristic (AUCs) curve more than 0.8. However, TF based on ResNet101, ResNet152, InceptionV3, and Densenet201 had equal or worse performances than DCNN (ResNet50) in grading thyroid tumor with AUCs less than 0.5. TF based on ResNet50 and VGG16 had a superior performance compared to DCNN (ResNet50) model for grading thyroid tumors based on ultrasound images.

Correlation between thyroid autoantibodies and the risk of thyroid papillary carcinoma

BACKGROUND

To investigate the correlation of thyroglobulin antibody (TgAb) and thyroid peroxidase antibody (TPOAb) with the risk of papillary thyroid carcinoma (PTC).

METHODS

The clinical data of 322 patients with pathologically confirmed thyroid nodules who underwent surgical treatment in Lishui Hospital of Zhejiang University from January 2018 to December 2019 were enrolled in this study. The enrolled patients were divided into a benign nodule group and a PTC group according their pathological results. Comparison was drawn based around the difference of thyroid autoantibody distribution between groups and its correlation with the risk of PTC.

RESULTS

The positive rate of TgAb in the PTC group was significantly higher than that in the benign nodule group (P<0.05). The incidence of PTC was significantly higher in TgAb positive patients in the presence of negative TPOAb (P<0.05). Further regression analysis revealed positive TgAb to be a risk factor of PTC (OR =3.097, P<0.05), while age ≥55 years old (OR =0.188, P<0.05) and nodule diameter ≥10 mm (OR =0.064, P<0.05) reduced the risk of PTC. Simultaneously, positive TgAb was also a risk factor for PTC in females (OR =3.532, P<0.05), but not in males (P>0.05). The risk of PTC in females was not associated with further increase in the titer of TgAb.

CONCLUSIONS

TgAb may be associated with an increased risk of PTC in females, but there is no clear correlation between the risk of PTC and higher antibody titer in these patients.

Discriminating Malignancy in Thyroid Nodules: The Nomogram Versus the Kwak and ACR TI-RADS

OBJECTIVE

To develop an easy-to-use nomogram for discrimination of malignant thyroid nodules and to compare diagnostic efficiency with the Kwak and American College of Radiology (ACR) Thyroid Imaging, Reporting and Data System (TI-RADS).

STUDY DESIGN

Retrospective diagnostic study.

SETTING

The Second Hospital of Shandong University.

SUBJECTS AND METHODS

From March 2017 to April 2019, 792 patients with 1940 thyroid nodules were included into the training set; from May 2019 to December 2019, 174 patients with 389 nodules were included into the validation set. Multivariable logistic regression model was used to develop a nomogram for discriminating malignant nodules. To compare the diagnostic performance of the nomogram with the Kwak and ACR TI-RADS, the area under the receiver operating characteristic curve, sensitivity, specificity, and positive and negative predictive values were calculated.

RESULTS

The nomogram consisted of 7 factors: composition, orientation, echogenicity, border, margin, extrathyroidal extension, and calcification. In the training set, for all nodules, the area under the curve (AUC) for the nomogram was 0.844, which was higher than the Kwak TI-RADS (0.826, P = .008) and the ACR TI-RADS (0.810, P < .001). For the 822 nodules >1 cm, the AUC of the nomogram was 0.891, which was higher than the Kwak TI-RADS (0.852, P < .001) and the ACR TI-RADS (0.853, P < .001). In the validation set, the AUC of the nomogram was also higher than the Kwak and ACR TI-RADS (P < .05), each in the whole series and separately for nodules >1 or ≤1 cm.

CONCLUSIONS

When compared with the Kwak and ACR TI-RADS, the nomogram had a better performance in discriminating malignant thyroid nodules.

Lymphovascular invasion of papillary thyroid carcinoma revisited in the era of active surveillance

INTRODUCTION

Lymphovascular invasion (LVI) is associated with disease recurrence and compromised survival in patients with thyroid cancer. Nonetheless, LVI is not identifiable on preoperative ultrasound or cytologic assessment. We aimed to explore the clinicopathological features associated with LVI.

PATIENTS AND METHODS

We conducted a retrospective review of our prospectively maintained database from 2009 to 2018. Multivariate analyses were performed to determine the associations between clinicopathological parameters and LVI. Generalized additive models were used to examine the nonlinear relationship between continuous variables and LVI.

RESULTS

A total of 795 patients were included in the analysis, and 174 (22%) had LVI. Patients' age (odds ratio [OR] = 0.982), tumor size (OR = 1.466), clinical lymphadenopathy (OR = 6.975), and advanced extrathyroidal extension (OR = 2.938) were independently associated with LVI. In the subset analysis of 198 patients with available genetic information, tumor size (OR = 1.599), clinical lymph node metastasis (OR = 3.657), and TERT promoter mutation (OR = 4.726) were predictive of LVI. Among 573 patients who had no clinical lymphadenopathy or advanced extrathyroidal extension, tumor size was the only predictor of LVI. Tumor size >1.5 cm had an increased risk of LVI based on the generalized additive model plot and receiver operating characteristic curve analysis.

CONCLUSION

Tumor size is positively associated with the risk of LVI in papillary thyroid cancer. To avoid delayed treatment in patients with LVI, a tumor size of 1.5 cm may be considered as the safe upper limit for active surveillance.

Serum biomarkers for thyroid cancer

The high prevalence of thyroid cancer requires a reliable serum biomarker for diagnosis and prognostic monitoring. Serum thyroglobulin has been established as the primary postoperative and postablative monitoring biomarker for this malignancy. However, the presence of thyroglobulin antibody imposes a significant interference on its overall management, which cannot be diminished by currently available assays. Trends on the level of the thyroglobulin antibody during follow-up is considered as a surrogate biomarker, but controversy exists. A variety of alternative biomarkers are being proposed and investigated, nevertheless, clinical trials and prospective validations are needed before they can be regarded as clinically viable serum parameters for thyroid cancer.

Interobserver agreement and efficacy of consensus reading in Kwak-, EU-, and ACR-thyroid imaging recording and data systems and ATA guidelines for the ultrasound risk stratification of thyroid nodules

PURPOSE

To investigate the interobserver agreement (IA) and the impact of consensus reading using four risk stratification systems for thyroid nodules (TN).

METHODS

Four experienced specialists independently rated US images of 80 TN according to the Kwak-TIRADS, EU-TIRADS, ACR TI-RADS, and ATA Guidelines. The cases were randomly extracted from a prospectively acquired database (n > 1500 TN). The observers were blinded to clinical data. This study was divided into two sessions (S1 and S2) with 40 image sets each. After every session, a consensus reading was carried out (C1, C2). Subsequently, the effect of C1 was tested in S2 with 40 new cases followed by C2. Fleiss' kappa (κ) was calculated for S1 and S2 to estimate the IA and learning curves. The results of C1 and C2 were used as reference for diagnostic accuracy calculations.

RESULTS

IA significantly increased (p < 0.01) after C1 with κ values of 0.375 (0.615), 0.411 (0.596), 0.321 (0.569), and 0.410 (0.583) for the Kwak-TIRADS, EU-TIRADS, ACR TI-RADS, and ATA Guidelines in S1 (S2), respectively. ROC analysis (C1 + C2) revealed similar areas under the curve (AUC) for the Kwak-TIRADS, EU-TIRADS, ACR TI-RADS, and ATA Guidelines (0.635, 0.675, 0.694, and 0.654, respectively, n.s.). AUC did not increase from C1 (0.677 ± 0.010) to C2 (0.632 ± 0.052, n.s.). ATA Guidelines were not applicable in five cases.

CONCLUSIONS

IA and diagnostic accuracy were very similar for the four investigated risk stratification systems. Consensus reading sessions significantly improved the IA but did not affect the diagnostic accuracy.

Thyroid imaging reporting and data system combined with Bethesda classification in qualitative thyroid nodule diagnosis

OBJECTIVE

We aimed to investigate the value of the combined use of high-resolution ultrasound thyroid imaging reporting and data system (TI-RADS) classification and thyroid fine needle aspiration cytology (Bethesda classification) for the qualitative diagnosis of benign and malignant thyroid nodules.

METHODS

We enrolled 295 patients with 327 thyroid nodules who were scheduled to undergo thyroid nodule surgery. Before surgery, all the patients underwent ultrasound and scoring with the TI-RADS classification, along with thyroid fine needle biopsy cytology under ultrasound guidance (US-FNAC) and scoring with the Bethesda classification. After surgery, the TI-RADS and Bethesda classification scores, separately and in combination, were compared with the postoperative pathological results in terms of the differential diagnosis of thyroid nodules.

RESULTS

TI-RADS classification score 4 exhibited the highest diagnostic value for thyroid cancer; the sensitivity, specificity, and accuracy were 92.7%, 70.7%, and 87.1%, respectively, whereas the Kappa and receiver-operating characteristics (ROC) values were 0.651 and 0.817, respectively. Moreover, Bethesda classification score 3 exhibited the highest diagnostic value for thyroid cancer; the sensitivity, specificity, and accuracy were 90.0%, 94.3%, and 91.1%, respectively, whereas the Kappa and ROC values were 0.78 and 0.914, respectively. With regard to the combined diagnostic method, a score of 7 exhibited the highest diagnostic value for thyroid cancer; the sensitivity, specificity, and accuracy were 97.3%, 92.0%, and 95.9%, respectively, whereas the Kappa and ROC values were 0.893 and 0.946, respectively.

CONCLUSION

The combination of high-resolution ultrasonography TI-RADS classification and US-FNAC (Bethesda classification) can improve the accuracy of malignant thyroid nodules diagnosis.

Diagnosis of Thyroid Nodules: Performance of a Deep Learning Convolutional Neural Network Model vs. Radiologists

Computer-aided diagnosis (CAD) systems hold potential to improve the diagnostic accuracy of thyroid ultrasound (US). We aimed to develop a deep learning-based US CAD system (dCAD) for the diagnosis of thyroid nodules and compare its performance with those of a support vector machine (SVM)-based US CAD system (sCAD) and radiologists. dCAD was developed by using US images of 4919 thyroid nodules from three institutions. Its diagnostic performance was prospectively evaluated between June 2016 and February 2017 in 286 nodules, and was compared with those of sCAD and radiologists, using logistic regression with the generalized estimating equation. Subgroup analyses were performed according to experience level and separately for small thyroid nodules 1–2 cm. There was no difference in overall sensitivity, specificity, positive predictive value (PPV), negative predictive value and accuracy (all p > 0.05) between radiologists and dCAD. Radiologists and dCAD showed higher specificity, PPV, and accuracy than sCAD (all p < 0.001). In small nodules, experienced radiologists showed higher specificity, PPV and accuracy than sCAD (all p < 0.05). In conclusion, dCAD showed overall comparable diagnostic performance with radiologists and assessed thyroid nodules more effectively than sCAD, without loss of sensitivity.

The diagnostic value of the ultrasound gray scale ratio for different sizes of thyroid nodules

At present, hypoechogenicity, as one of the clinically relevant features associated with suspicion of malignant thyroid disease, is affected by the variability of modules and the experience of sonographers, thus leading to unsatisfying results. We propose the ultrasound gray scale ratio (UGSR) to obtain an objective, numerical estimate of the echogenicity degree in different‐sized thyroid nodules, and we then evaluate its diagnostic efficacy in differentiating benign and malignant thyroid lesions. In total, 553 ultrasound images of thyroid nodules from one kind of ultrasonographic scanner were analyzed, among which 281 were papillary thyroid carcinomas (PTCs) and 272 were nodular goiters (NGs). The UGSR of the PTCs, NGs, and surrounding normal thyroid tissue was measured by image analysis software. The best cut‐off value for distinguishing various sizes of PTCs and NGs was determined by receiver operating characteristic (ROC) curve analysis. As the UGSR increased, the sensitivity of the diagnosing PTCs decreased, and the specificity increased. When the maximum Jordan index was 0.611, the best cut‐off value was 0.692, and the corresponding sensitivity and specificity of diagnosing PTCs were 87.9% and 73.2%, respectively. For the analysis of subgroups of different tumor sizes, as the size of thyroid nodules increased from 0.3 to 2 cm, the sensitivity of the diagnosis of PTCs decreased from 97.5% to 58.8%, and the specificity increased from 72.4% to 90.9%. These results strongly suggest that the UGSR is an appropriate objective, numerical method for estimating the echogenicity degree and has various diagnostic efficacies in different‐sized thyroid nodules. Thus, the UGSR can be used as an additional ultrasound parameter in the diagnosis of different‐sized PTCs and NGs.

Echogenic foci in thyroid nodules: diagnostic performance with combination of TIRADS and echogenic foci

Background

The malignancy risks of various echogenic foci in thyroid nodules are not consistent. The association between malignancy and echogenic foci and various Thyroid Imaging Reporting and Data System (TIRADS) in thyroid nodules has not been evaluated. We evaluated the malignancy probability and diagnostic performance of thyroid nodules with various echogenic foci and in combination with TIRADS.

Methods

This retrospective study was approved by Institutional Review Board. The data were retrospectively collected from January 2013 to December 2014. In total, 954 patients (mean age, 50.8 years; range, 13–86 years) with 1112 nodules were included. Using χ² test, we determined the prevalence of benign and malignant nodules among those with and without echogenic foci; we associated each of 6 echogenic foci types with benign and malignant nodules. Diagnostic performance was compared between the 6 types alone and in combination with various TIRADS.

Results

Among 1112 nodules, 390 nodules (35.1%) were found to have echogenic foci, and 722 nodules (64.9%) were not. Among nodules with echogenic foci, 254 nodules (65.1%) were malignant. The punctate echogenic foci with comet-tail artifact showed malignancy rate of 77.8% in solid and predominantly solid nodules. Our study demonstrated relatively low PPV (33.3–56.4%) in nodules with large echogenic foci without shadowing, macrocalcification, and peripheral curvilinear or eggshell echogenic foci with or without shadowing. However, when combined with high suspicion category of TIRADS, PPV increased to 50.0–90.9%.

Conclusion

Combination with TIRADS with different types of echogenic foci offer better stratification of the malignancy risk.

Electronic supplementary material

The online version of this article (10.1186/s12880-019-0328-2) contains supplementary material, which is available to authorized users.

Comparison among TIRADS (ACR TI-RADS and KWAK- TI-RADS) and 2015 ATA Guidelines in the diagnostic efficiency of thyroid nodules

PURPOSE

To compare the value of Thyroid Imaging Reporting and Data Systems proposed by Kwak (KWAK-TIRADS) and ACR (ACR TI-RADS) and 2015 American Thyroid Association (ATA) guidelines in the diagnosis of surgically resected thyroid nodules.

METHODS

From January 2015 to December 2015, 2544 thyroid nodules in 1758 patients who underwent thyroidectomy at our center were included. The KWAK-TIRADS category, ACR TI-RADS and ultrasound (US) pattern based on ATA guidelines were assigned to each thyroid nodule. Nodules were divided into groups according to their maximal diameter further.

RESULTS

Of all the nodules, 863 (33.9%) were benign, whereas 1681 (66.1%) were malignant. The malignancy percentage of ACR TI-RADS category 1, 2, 3, 4, and 5 were 0%, 1.3%, 9.1%, 52.5%, and 88.8%, respectively. KWAK-TIRADS and ATA guidelines showed a better diagnostic efficiency than ACR TI-RADS (P < 0.01). ACR TI-RADS demonstrated a higher specificity (79.7%, P < 0.05), whereas the ATA US pattern had a higher sensitivity (95.5%, P < 0.01). The TIRADS (KWAK-TIRADS and ACR TI-RADS) category and ATA guidelines performed better in differentiating nodules >1 cm. KWAK-TIRADS showed better diagnostic efficiency than the other methods in differentiating nodules >1 cm (AUC: 0.92, P < 0.01).

CONCLUSIONS

KWAK-TIRADS and ATA guidelines provide a better diagnostic efficiency than ACR TI-RADS. The TIRADS (KWAK-TIRADS and ACR TI-RADS) category and ATA guidelines perform better in differentiating nodules >1 cm than nodules ≤1 cm. KWAK-TIRADS perform better in differentiating nodules >1 cm than other methods.

Diagnostic performance of 2015 American Thyroid Association guidelines and inter-observer variability in assigning risk category

•

Risk of malignancy at 75–90% in the high suspicion sonographic pattern of the 2015 ATA guidelines may have been over estimated.

•

The 2015 ATA guidelines show moderate inter-observer agreement for assigning a final risk category.

•

The study highlights certain sonographic features which are not included in any ATA risk categories leading to inter-observer variability.

Objective

To determine the interobserver variability of the 2015 American Thyroid Association (ATA) thyroid guidelines and to evaluate the diagnostic accuracy of the guidelines in detecting thyroid cancer.

Materials and methods

Sonographic patterns of 189 thyroid lesions were retrospectively analyzed by two radiologists according to the 2015 guidelines. The risk of malignancy was calculated for each pattern and compared with the published expected risk of malignancy.

Results

The observed risk of malignancy for very low suspicion, low suspicion, intermediate suspicion and high suspicion patterns were 2%, 12.7%, 26.3% and 29.8% respectively. Interobserver agreement for final category assignment was moderate (κ 0.518).

Conclusion

The estimated risk of malignancy in the high suspicion pattern of the 2015 ATA thyroid biopsy guidelines appears to be less than stated. However, this needs further validation in a larger cohort study.

A computer-aided diagnosis system for the assessment and characterization of low-to-high suspicion thyroid nodules on ultrasound

AIM OF THE STUDY

To compare the diagnostic performance of a commercially available computer-aided diagnosis (CAD) system for thyroid ultrasound (US) with that of a non-computer-aided radiologist in the characterization of low-to-high suspicion thyroid nodules.

METHODS

This retrospective study included a consecutive series of adult patients referred for US-guided fine-needle aspiration biopsy (FNAB) of a thyroid nodule. All patients were eligible for thyroid nodule FNAB according to the current international guidelines. An interventional radiologist experienced in thyroid imaging acquired the US images subsequently used for post-processing, performed FNAB and provided the US features of each nodule. A radiology resident and an endocrinology resident in consensus performed post-processing using the CAD system to assess the same nodule characteristics. The diagnostic performance and agreement of US features between the CAD system and the radiologist were compared.

RESULTS

Sixty-two patients (50 F; age 60 ± 12 years) were enrolled: 77.4% (48/62) of thyroid nodules were benign, 22.6% (14/62) were undetermined to malignant and required follow-up or surgery. Interobserver agreement between the CAD system and the radiologist was substantial for orientation (K = 0.69), fair for composition (K = 0.36), echogenicity (K = 0.36), K-TIRADS (K = 0.29), and slight for margins (K = 0.03). The radiologist demonstrated a significantly higher sensitivity than the CAD system (78.6% vs. 21.4%; P = 0.008), while there was no statistical difference in specificity (66.7% vs. 81.3%; P = 0.065).

CONCLUSION

This CAD system is less sensitive than an experienced radiologist and showed slight-to-substantial agreement with the radiologist for the characterization of thyroid nodules. Although it is an innovative tool with good potential, additional efforts are needed to improve its diagnostic performance.

Interreader agreement of PI-RADS v. 2 in assessing prostate cancer with multiparametric MRI: A study using whole-mount histology as the standard of reference

BACKGROUND

Most studies assessing interreader agreement of Prostate Imaging Reporting and Data System v. 2 (PI-RADS v2) have used biopsy as the standard of reference, thus carrying the risk of not definitively noting all existent cancers.

PURPOSE

To evaluate the interreader agreement in assessing prostate cancer (PCa) of PI-RADS v2, using whole-mount histology as the standard of reference.

STUDY TYPE

Monocentric prospective cohort study.

POPULATION

In all, 48 patients with biopsy-proven PCa referred for radical prostatectomy, undergoing staging multiparametric magnetic resonance imaging (mpMRI) between May 2016 to February 2017.

FIELD STRENGTH/SEQUENCE

3.0T system using high-resolution T₂ -weighted imaging, diffusion-weighted imaging (echo-planar imaging with maximum b-value 2000 sec/mm² ), and dynamic contrast-enhanced imaging (T₁ -weighted high resolution isotropic volume examination; THRIVE) ASSESSMENT: Three radiologists blinded to final histology (2-8 years of experience) analyzed mpMRI images independently, scoring imaging findings in accordance with PI-RADS v2. On a per-lesion basis, we calculated overall and pairwise interreader agreement in assigning PI-RADS categories, as well as assessing malignancy with categories ≥3 or ≥4, and stage ≥pT3.

STATISTICAL TESTS

Cohen's kappa analysis of agreement.

RESULTS

On 71 lesions found on histology, there was moderate agreement in assigning PI-RADS categories to all cancers (k = 0.53) and clinically significant cancers (csPCa) (k = 0.47). Assessing csPCa with PI-RADS ≥4 cutoff provided higher agreement than PI-RADS ≥3 cutoff (k = 0.63 vs. 0.57). Interreader agreement was higher between more experienced readers, with the most experienced one achieving the highest cancer detection rate (0.73 for csPCa using category ≥4). There was substantial agreement in assessing stage ≥pT3 (k = 0.72).

DATA CONCLUSION

We found moderate to substantial agreement in assigning the PI-RADS v2 categories and assessing the spectrum of cancers found on whole-mount histology, with category 4 as the most reproducible cutoff for csPCa. Readers' experience influenced interreader agreement and cancer detection rate.

LEVEL OF EVIDENCE

2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:546-555.

Effect of Implementing Community of Practice Modified Thyroid Imaging Reporting and Data System on Reporting Adherence and Number of Thyroid Biopsies

RATIONALE AND OBJECTIVES

Thyroid nodules are common in the population, although the rate of malignancy is relatively low (5%-15%). The purpose of this study was to determine if introducing a modified standardized reporting format and management algorithm (Thyroid Imaging Reporting and Data System [TI-RADS]) affects radiologist reporting adherence, number of thyroid biopsies, and other measurable outcomes.

MATERIALS AND METHODS

All thyroid biopsies performed over two 6-month periods were evaluated at a tertiary care hospital with Research Ethics Board approval. The first period was before implementation of TI-RADS and the second was several months after implementation of TI-RADS (using a modified version made through a multidisciplinary collaboration). The number of biopsies performed was determined in each of the two periods as well as the percent of positive malignancy, wait times, and rates of non-diagnostic/unsatisfactory and inconclusive biopsies, which included atypia of undetermined significance (AUS) and follicular lesion of undetermined significance (FLUS).

RESULTS

The average number of biopsies performed prior to implementing modified Kwak's TI-RADS was 74 thyroid biopsies per month and the average number of diagnostic ultrasounds was 271. After the introduction of modified Kwak's TI-RADS, the average number of thyroid biopsies decreased to 60 per month (an 18.9% reduction, P < .05), and the number of diagnostic ultrasound increased to 287 per month (a 5.9% increase from 2016 to 2017). The average wait time for a thyroid biopsy decreased from 5 to 3 weeks (P < .05). There was a slight increase in the rate of positive malignancy results (from 15% to 18%), although it was not statistically significant. The rate of non-diagnostic/unsatisfactory and inconclusive results (including AUS and FLUS) remained unchanged (18% AUS/FLUS/15% non-diagnostic/unsatisfactory before and 17% AUS/FLUS/15% non-diagnostic/unsatisfactory after TI-RADS introduction, P > .05).

CONCLUSIONS

Introduction of a multidisciplinary-approved standardized reporting system with evidence-based management recommendations led to no statistically significant change in the number of diagnostic ultrasounds but a statistically significant reduction in the number of monthly thyroid biopsies and associated reduction in wait times.

A novel TIRADS of US classification

BACKGROUND

Thyroid imaging reporting and data system (TIRADS) is the assessment of a risk stratification of thyroid nodules, usually using a score. However, there is no consensus as to the version of TIRADS for reporting the results of thyroid ultrasound in clinic. The objective of this study is to develop a practical TIRADS with which to categorize thyroid nodules and stratify their malignant risk.

METHODS

A TIRADS scoring system was developed to provide more decision levels than standard scoring through the selection of the ultrasound features which include the calcification shape, margins, taller-than-wide, internal echo, blood flow quantization of features, setting of the weight, and calculation of the score. Ultimately, the accuracy of our TIRADS was evaluated by comparing with the results of current vision of TIRADS and thyroid radiologist in 153 patients who had US-guided fine-needle aspiration biopsy.

RESULTS

Classification results showed that the total accuracy reached 97% (100% of malignant and 95% of the benign) in 153 cases (benign:78, malignant:75). The percentages of malignancy is defined in our TIRADS were as follows: TIRADS 2 (0% malignancy), TIRADS 3 (3.6% malignancy), TIRADS 4 (17-75% malignancy), and TIRADS 5 (98% malignancy).

CONCLUSIONS

We established a novel TIRADS to predict the malignancy risk of the thyroid nodules based on six categories US features by a scoring system, which included a standardized vocabulary and score and a quantified risk assessment. The results showed that objective quantitative classification of thyroid nodules by our TIRADS can be useful in guiding management decisions.

Differential diagnosis value of the ultrasound gray scale ratio for papillary thyroid microcarcinomas and micronodular goiters

Background

To investigate the differential diagnosis value of the ultrasound gray scale ratio (UGSR) for papillary thyroid microcarcinomas (PTMCs) and micronodular goiters (MNGs).

Methods

A retrospective analysis was performed using ultrasound images from 521 PTMC patients (561 PTMC lesions) and 405 MNG patients (515 MNG lesions). All cases were surgically and histologically confirmed. Gray scale values of the thyroid lesions and the surrounding normal thyroid tissue were measured. The thyroid lesion to normal thyroid tissue (UGSR) was calculated. Statistical analysis was performed with Mann-Whitney test. Receiver operating characteristic curve determined the optimal UGSR threshold for differentiating PTMCs and MNGs.

Results

In 561 PTMCs, the mean UGSR was 0.54 (SD: 0.16; range: 0.24-1.26). In 515 MNGs, the mean UGSR was 0.87 (SD: 0.22; range: 0.34-2.06), with significant difference between values of PTMCs and MNGs (P<0.001). The UGSR area under the curve to differentiate PTMCs and MNGs was 0.895. When the UGSR decreased, the UGSR to PTMC sensitivity decreased and the specificity increased. When the UGSR was chosen to be 0.99, 0.72, 0.63 or 0.34, the sensitivity was 98.4% and 87.0%, 73.8% and 5.9% respectively, and specificity was 25.1% and 80.4%, 90.1% and 100.0% respectively. When the UGSR was 0.72, the Youden index maximum was 0.674.

Conclusions

The UGSR allows potential differentiation PTMCs and MNGs.

Reconsideration of tumor size threshold for total thyroidectomy in differentiated thyroid cancer

BACKGROUND

The optimal extent of surgery for differentiated thyroid cancer may not be well recognized initially. Identification of intermediate-risk features on surgical pathology may prompt the need for completion thyroidectomy if a lobectomy is performed. In this study, we examined the factors in relation to the need for completion thyroidectomy.

METHODS

We studied consecutive patients who underwent thyroidectomy for differentiated thyroid cancer from 2008 to 2017. Total thyroidectomy was indicated when tumor size >4 cm, clinical extrathyroidal extension, clinical lymph node metastasis, or distant metastasis was present. The need for completion thyroidectomy was defined as the presence of aggressive histology, extrathyroidal extension, lymphovascular invasion, or non-low-risk nodal metastasis.

RESULTS

Among 771 patients, 155 (20%) were definitely indicated for total thyroidectomy. The need for completion thyroidectomy was identified in 273 (44%) of the 616 patients initially eligible for lobectomy. The proportions of patients requiring completion thyroidectomy were 18% and 57% for microcarcinomas and tumors of 1-4 cm, respectively. Receiver operating characteristic curve analysis indicated that tumor size ≥1.1 cm had the highest accuracy of prediction. Multivariate logistic regression revealed that tumor size and BRAF V600E mutation were independent factors predicting the risk of requiring completion thyroidectomy.

CONCLUSION

A substantial portion of patients with differentiated thyroid cancer who are preoperatively eligible for lobectomy would be found to have intermediate-risk pathologic features. This should be incorporated into the shared decision making before surgery.

Evaluation and Management of Indeterminate Thyroid Nodules: The Revolution of Risk Stratification Beyond Cytological Diagnosis

In accordance with National Guidelines, we currently follow a linear approach to the diagnosis of thyroid nodules, with management decision based primarily on a cytological diagnosis following fine-needle aspiration biopsy. However, 25% of these biopsies render an indeterminate cytology, leaving uncertainty regarding appropriate management. Individualizing the risk of malignancy of these nodules could improve their management significantly. We summarize the current evidence on the relevance of clinical information, radiological features, cytological features, and molecular markers tests results and describe how these can be integrated to personalize the management of thyroid nodules with indeterminate cytology. Several factors can be used to stratify the risk of malignancy in thyroid nodules with indeterminate cytology. Male gender, large tumors (>4 cm), suspicious sonographic patterns, and the presence of nuclear atypia on the cytology are all associated with an increased cancer prevalence. The added value of current molecular markers in the risk stratification process needs further study because their performance seems compromised in some clinical settings and remains to be validated in others. Risk stratification is possible in thyroid nodules with indeterminate cytology using data that are often underused by current guidelines. Future guidelines should integrate these factors and personalize the recommended diagnostic and therapeutic approaches accordingly.

Interobserver agreement of various thyroid imaging reporting and data systems

Ultrasonography is the best available tool for the initial work-up of thyroid nodules. Substantial interobserver variability has been documented in the recognition and reporting of some of the lesion characteristics. A number of classification systems have been developed to estimate the likelihood of malignancy: several of them have been endorsed by scientific societies, but their reproducibility is yet to be assessed. We evaluated the interobserver variability of the AACE/ACE/AME, ACR, ATA, EU-TIRADS and K-TIRADS classification systems and the interobserver concordance in the indication to FNA biopsy. Two raters independently evaluated 1055 ultrasound images of thyroid nodules identified in 265 patients at multiple time points, in two separate sets (501 and 554 images). After the first set of nodules, a joint reading was performed to reach a consensus in the feature definitions. The interobserver agreement (Krippendorff alpha) in the first set of nodules was 0.47, 0.49, 0.49, 0.61 and 0.53, for AACE/ACE/AME, ACR, ATA, EU-TIRADS and K-TIRADS systems, respectively. The agreement for the indication to biopsy was substantial to near-perfect, being 0.73, 0.61, 0.75, 0.68 and 0.82, respectively (Cohen's kappa). For all systems, agreement on the nodules of the second set increased. Despite the wide variability in the description of single ultrasonographic features, the classification systems may improve the interobserver agreement that further ameliorates after a specific training. When selecting nodules to be submitted to FNA biopsy, that is main purpose of these classifications, the interobserver agreement is substantial to almost perfect.

Validation of Three Scoring Risk-Stratification Models for Thyroid Nodules

BACKGROUND

To minimize potential harm from overuse of fine-needle aspiration, Thyroid Imaging Reporting and Data Systems (TIRADSs) were developed for thyroid nodule risk stratification. The purpose of this study was to perform validation of three scoring risk-stratification models for thyroid nodules using ultrasonography features, a web-based malignancy risk-stratification system, and a model developed by the Korean Society of Thyroid Radiology and the American College of Radiology.

METHODS

Using ultrasonography images, radiologists assessed thyroid nodules according to the following criteria: internal content, echogenicity of the solid portion, shape, margin, and calcifications. A total of 954 patients (M_age = 50.8 years; range 13-86 years) with 1112 nodules were evaluated at the authors' institute from January 2013 to December 2014. The discrimination ability of the three models was assessed by estimating the area under the receiver operating characteristic curve. Additionally, Hosmer-Lemeshow goodness-of-fit statistics (calibration ability) were used to evaluate the agreement between the observed and expected number of nodules that were benign or malignant.

RESULTS

Thyroid malignancy was present in 37.2% (414/1112) of nodules. According to the 14-point web-based scoring risk-stratification system, malignancy risk ranged from 4.5% to 100.0% and was positively associated with an increase in risk scores. The areas under the receiver operating characteristic curve of the validation set were 0.884 in the web-based model, 0.891 in the Korean Society of Thyroid Radiology model, and 0.875 in the American College of Radiology model. The Hosmer-Lemeshow goodness-of-fit test indicated that the web-based scoring system showed the best-calibrated result, with a p-value of 0.078.

CONCLUSION

The three scoring risk-stratification models using the ultrasonography features of thyroid nodules to stratify malignancy risk showed acceptable predictive accuracy and similar areas under the curve. The web-based scoring system demonstrated the strongest agreement in calibration ability analysis. The easily accessible automated web-based scoring risk-stratification system may overcome the complexity of the various Thyroid Imaging Reporting and Data System guidelines and provide simplified guidance on personalized and optimal management in real practice.

Thyroid Nodules With Nondiagnostic Cytologic Results: Follow-Up Management Using Ultrasound Patterns Based on the 2015 American Thyroid Association Guidelines

OBJECTIVE

The purpose of this study was to evaluate the malignancy rate of nodules with nondiagnostic cytologic results based on the American Thyroid Association (ATA) ultrasound (US) patterns and to suggest management guidelines for these nodules.

MATERIALS AND METHODS

From January 2013 to December 2014, 441 nodules (≥ 1 cm) were found in 437 patients with nondiagnostic results of ultrasound (US)-guided fine-needle aspiration biopsy (nondiagnostic nodules). A total of 191 nodules that were cytopathologically confirmed or were smaller (> 3 mm) at follow-up US were enrolled. The US findings of each nodule were reviewed. One radiologist classified the nodules into the following five categories according to the 2015 ATA guidelines: high, intermediate, low, and very low suspicion for malignancy and benign. The reference standard was histopathologic confirmation. Nodules that were smaller at follow-up US were considered benign. The malignancy rate of each category was calculated.

RESULTS

Among a total 191 nodules, 20 (10.5%) were malignant. Solid composition, marked hypoechogenicity, microlobulated or irregular margins, microcalcifications, and taller-than-wide shape were more frequently seen in malignant nodules (all p < 0.001). The malignancy rate of nodules with very low suspicion of malignancy was 0% (0/58); low, 0% (0/45); intermediate, 10.3% (6/58); and high, 46.7% (14/30) (p < 0.001).

CONCLUSION

When US findings of thyroid nodules are assessed according to the 2015 ATA guidelines, nondiagnostic thyroid nodules with very-low- or low-suspicion US patterns can be followed up with US. Nondiagnostic nodules with intermediate or highly suspicious US patterns should be evaluated with repeat US-guided fine-needle aspiration biopsy.

Ultrasonography-Based Classification and Reporting System for the Malignant Risk of Thyroid Nodules

OBJECTIVE

The aim of this study was to test the predictive value of a Thyroid Imaging Reporting and Data System (TI-RADS) for malignant thyroid nodules.

METHODS

Ultrasonographic data was examined for 910 thyroid nodules with histopathologically confirmed diagnoses. Nodules were placed into incomplete (category 0) or complete final categories (1, 2, 3a, 3b, 3c, 4, or 5) based on the presence and number of ultrasonographic features of malignancy, and the predictive value for the malignancy of nodules in categories 2-4 was assessed.

RESULTS

The overall rate of malignancy among thyroid nodules included in the study was 59.34%. The rate of malignancy gradually increased according to TI-RADS categories as follows: category 2, 5.4%; category 3 (a-c), 36% to 92%; and category 4, 99.0%. When nodules of category 2 were counted as benign, the reliability of the TI-RADS classification for determining the risk of malignancy was as follows; sensitivity, 98.15%; specificity, 47.84%; positive predictive value, 73.31%; negative predictive value, 94.65%; and odds ratio, 48.61.

CONCLUSIONS

The TI-RADS classification used in this study is relatively simple and provides a reliable measure of the risk of malignancy of thyroid nodules.

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.

Trends in radiology and experimental research

European Radiology Experimental, the new journal launched by the European Society of Radiology, is placed in the context of three general and seven radiology-specific trends. After describing the impact of population aging, personalized/precision medicine, and information technology development, the article considers the following trends: the tension between subspecialties and the unity of the discipline; attention to patient safety; the challenge of reproducibility for quantitative imaging; standardized and structured reporting; search for higher levels of evidence in radiology (from diagnostic performance to patient outcome); the increasing relevance of interventional radiology; and continuous technological evolution. The new journal will publish not only studies on phantoms, cells, or animal models but also those describing development steps of imaging biomarkers or those exploring secondary end-points of large clinical trials. Moreover, consideration will be given to studies regarding: computer modelling and computer aided detection and diagnosis; contrast materials, tracers, and theranostics; advanced image analysis; optical, molecular, hybrid and fusion imaging; radiomics and radiogenomics; three-dimensional printing, information technology, image reconstruction and post-processing, big data analysis, teleradiology, clinical decision support systems; radiobiology; radioprotection; and physics in radiology. The journal aims to establish a forum for basic science, computer and information technology, radiology, and other medical subspecialties.

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.

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

OBJECTIVE

The aim of this study was to investigate and compare the diagnostic performances of the Thyroid Imaging Reporting and Data System (TIRADS) in differentiating benign and malignant thyroid nodules according to the level of physician experience.

MATERIALS AND METHODS

From March to October 2013, 1102 patients with 1128 thyroid nodules who underwent initial ultrasound-guided fine needle aspiration were included in this study. Thyroid nodules were categorized according to TIRADS. Diagnostic performances of ultrasound were compared according to performer experience using the χ test or Fisher exact test.

RESULTS

Of 1128 thyroid nodules, 281 were malignant, and 847 were benign. The risk of malignancy of each TIRADS category by the experienced and less experienced physicians were as follows: category 3 (0.9% vs 0%), category 4a (3.5% vs 1.3%), category 4b (7.3% vs 12.1%), category 4c (67.5% vs 44.9%), and category 5 (97.7% vs 76.5%). Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 99.1%, 35.9%, 52.5%, 35.5%, and 99.1%, respectively, for experienced physicians and 100%, 20.9%, 37.6%, 35.2%, and 100%, respectively, for less experienced physicians. Specificity, accuracy, and positive predictive value were statistically higher for experienced physicians than those for less experienced physicians (P < 0.001, 0.001, and 0.004). There was a significant difference in areas under the curve between the 2 groups (P < 0.001).

CONCLUSIONS

In conclusion, the diagnostic performance of the stratification of malignancy risk according to TIRADS categories was comparable between the experienced and less experienced physician groups. The application of TIRADS is reproducible, and it was easy to predict the probability of thyroid malignancy in both the experienced and less experienced physician groups.