Guidelines For Thyroid Nodules Research Articles

Ultrasound Imaging of Thyroid Pathologies: A Pictorial Review

AbstractWith its complex embryological origin, the thyroid can be affected by various congenital, developmental, benign, and malignant pathologies. Ultrasound, which is free from radiation and offers good spatial resolution, is the initial modality of choice in congenital hypothyroidism and is used in conjunction with scintigraphy. High-resolution ultrasound also aids in early diagnosis, risk stratification, and follow-up of nodules. While fine-needle aspiration cytology is the preferred method for further evaluation of thyroid nodules, ultrasound guidance reduces the likelihood of obtaining nondiagnostic samples. Numerous risk stratification guidelines for thyroid nodules have been developed by various societies over the past decade, with the most popular being the American College of Radiology—Thyroid Imaging Reporting and Data System. A comprehensive understanding of the varying morphological appearances of thyroid nodules and the consistent use of risk stratification guidelines can accurately detect incidental malignancies while avoiding unnecessary intervention in seemingly benign nodules.

Incidental thyroid carcinomas: experiences related to the surgery of head and neck cancers.

Incidental thyroid carcinomas (ITCs) in patients undergoing head and neck surgery are rare, but there are no standard guidelines for the treatment of this situation. This retrospective study sought to detail our experiences in the treatment of ITCs related to the surgery of head and neck cancers. We conducted a retrospective analysis of the data about the ITCs in the patients with head and neck cancer, who underwent surgical treatments at Beijing Tongren Hospital in the past 5 years. The number and size of the thyroid nodules, postoperative pathology, follow-up results, and other information were recorded in detail. All the patients underwent surgical treatment and were followed-up for >1 year. A total of 11 patients (10 male and 1 female) with ITC were included in this study. The patients had an average age of 58 years. Most of the patients (72.7%, 8/11) had laryngeal squamous cell cancer, and 7 were diagnosed with thyroid nodules on ultrasound. The surgical procedures for laryngeal and hypopharyngeal cancers included partial laryngectomy, total laryngectomy, and hypopharyngectomy. All the patients underwent thyroid stimulating hormone (TSH) suppression therapy. No recurrence or mortality events from thyroid carcinoma were observed. More attention needs to be paid to ITCs in head and neck surgery patients. Additionally, more research and the long-time follow-up of ITC patients are needed to extend understandings. For patients with head and neck cancers, if the suspicious thyroid nodules are found pre-operatively by ultrasound, fine-needle aspiration (FNA) is recommended. If FNA cannot be performed, the guidelines for thyroid nodules should be followed. In patients with postoperative ITC, TSH suppression therapy and follow-up is indicated.

The diagnostic efficacy and inappropriate biopsy rate of ACR TI-RADS and ATA guidelines for thyroid nodules in children and adolescents.

This study is aimed at evaluating the diagnostic efficacy and unnecessary fine-needle aspiration (FNA) rate of ultrasound-based risk stratification for thyroid nodules in the American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS) and the American Thyroid Association (ATA) risk stratification systems. Children and adolescents with pathology confirmed thyroid nodules were retrospectively included in this study. A total of 217 thyroid nodules from multicenter of Union Medical College Hospital, China Japan Friendship Hospital and Civil Aviation Hospital were included, the diagnostic efficiency and unnecessary FNA rate were calculated according to ACR and ATA guidelines. Among all thyroid nodules, 139 nodules were malignant, and 78 nodules were benign. Choosing ATA high suspicion and ACR TI-RADS TR5 as benign and malignant cut-off points, the area under the curve and sensitivity of ATA were higher than ACR (AUC: 0.887 vs 0.840, p=0.0037; sensitivity 81.3% vs 71.0%, P <0.049;specificity 96.2% vs 97.4%, p=1.000;specificity both 85.9%); choosing high/intermediate suspicion in ATA and ACR TR4/5 as benign and malignant cut-off points, the two guidelines demonstrated similar diagnostic efficacy (AUC:0.890 vs 0.897, p=0.6038, sensitivity 92.1% vs 93.5%, P =0.817;specificity both 85.9%, p=1.000). The inappropriate FNA rate of ACR guideline was relatively lower (ATA 42.9% vs ACR 27.2%, P <0.001). If ACR TI-RADS TR5 nodules less than 1.0cm were included in the FNA indication, the unnecessary biopsy rate would be further reduced to 17.9%. This study indicated that both ATA and ACR TI-RADS risk stratification systems could provide a feasible differential diagnosis of benign and malignant thyroid nodules, while the ACR risk stratification system demonstrates a lower rate of inappropriate FNA rate. In addition, it was necessary to further study the minimum FNA threshold of thyroid nodules in Children and adolescents in order to reduce the missed biopsy rate of malignant nodules.

Comparison of ACR-TIRADS to the ATA Guidelines for Thyroid Nodules: A Neck to Neck Comparison

Introduction: The goal of this study was to compare the performance characteristics of the American College of Radiology Thyroid Imaging Reporting and Data System (ACR-TIRADS) and the American Thyroid Association (ATA) systems in identifying malignant thyroid nodules. Methods: In a retrospective chart review, ultrasound images of all thyroid nodules biopsied in 2014- 2015 at a Canadian academic centre were reviewed by two radiologists. The ultrasound characteristics of thyroid nodules were compared with cytologic or pathologic results to determine the positive predictive value (PPV), negative predictive value (NPV), sensitivity and specificity for TIRADS and ATA in predicting cancer risk. Clinical course of nodules not requiring follow up or intervention according to ACR-TIRADS was described. Vascularity was added to ACR-TIRADS to determine whether sensitivity of TIRADS improves. Results: A total of 417 thyroid nodules were reviewed, 82% were benign (Bethesda II). The sensitivity, specificity, PPV, and NPV were 97%, 11%, 9%, 98%, and 70%, 29%, 18%, and 81% for ATA and TIRADS, respectively. Of the 10 nodules that did not need ultrasound follow up based on TIRADS criteria, 2 were malignant, the rest were FLUS. If vascularity was added to TIRADS (TIRADS-Vasc), the number of malignant cases missed could have been reduced by 43% (from 7 to 4 cases). Conclusions: TIRADS is more specific but less sensitive than ATA, and misses a small number of malignant nodules. Clinicians need to use their judgement to decide which nodules require biopsy as some malignant cases will be missed using TIRADS alone.

2020 Imaging Guidelines for Thyroid Nodules and Differentiated Thyroid Cancer: Korean Society of Thyroid Radiology.

Imaging plays a key role in the diagnosis and characterization of thyroid diseases, and the information provided by imaging studies is essential for management planning. A referral guideline for imaging studies may help physicians make reasonable decisions and minimize the number of unnecessary examinations. The Korean Society of Thyroid Radiology (KSThR) developed imaging guidelines for thyroid nodules and differentiated thyroid cancer using an adaptation process through a collaboration between the National Evidence-based Healthcare Collaborating Agency and the working group of KSThR, which is composed of radiologists specializing in thyroid imaging. When evidence is either insufficient or equivocal, expert opinion may supplement the available evidence for recommending imaging. Therefore, we suggest rating the appropriateness of imaging for specific clinical situations in this guideline.

Fine-Needle Aspiration of Subcentimeter Thyroid Nodules in the Real-World Management.

BackgroundThe Korea Thyroid Association published the revised guidelines for thyroid nodules in 2016. However, whether fine-needle aspiration is accurately performed based on indications and whether the results of this procedure are appropriately addressed according to clinical guidelines, particularly in subcentimeter nodules, are unclear.MethodsWe retrospectively analyzed the fine-needle aspiration data of 331 thyroid nodules of patients who were referred to a tertiary hospital clinic for fine-needle aspiration. Each nodule was categorized according to ultrasonography findings based on the recommendations of the Korea Thyroid Association for fine-needle aspiration. Only nodules with a final pathological diagnosis of benign or malignant made using the Bethesda system were included.ResultsUp to 32% of thyroid nodules that were not indicated for fine-needle aspiration were aspirated. Regarding subcentimeter nodules, only 28 of 123 (22.8%) aspirated nodules were indicated for fine-needle aspiration. Of the 49 malignant subcentimeter nodules, 33 (67.3%) underwent immediate surgery. Meanwhile, 14 (28.6%) nodules were lost to follow-up, and two (4.1%) were under active surveillance. Eighteen (36.7%) malignant subcentimeter nodules were not indicated for fine-needle aspiration but underwent surgical resection instead of active surveillance.ConclusionDespite the recommendations in the revised guidelines, several thyroid nodules that do not meet the indications for FNA are aspirated in real-world practice. To reduce overtreatment, a widespread knowledge of the correct indications for fine-needle aspiration is important in clinical practice, particularly for subcentimeter nodules.

Development and Validation of a Risk Scoring System Derived from Meta-Analyses of Papillary Thyroid Cancer.

BackgroundThe aim of this study was to develop a scoring system to stratify the risk of papillary thyroid cancer (PTC) and to select the proper management.MethodsWe performed a systematic search of MEDLINE and Embase. Data regarding patients’ prognoses were obtained from the included studies. Odds ratios (ORs) with statistical significance were extracted from the publications. To generate a risk scoring system (RSS), ORs were summed (RSS1), and summed after natural-logarithmic transformation (RSS2). RSS1 and RSS2 were compared to the eighth edition of the American Joint Committee on Cancer (AJCC) staging system and the 2015 American Thyroid Association (ATA) guidelines for thyroid nodules and differentiated thyroid carcinoma.ResultsFive meta-analyses were eligible for inclusion in the study. Eight variables (sex, tumour size, extrathyroidal extension, BRAF mutation, TERT mutation, histologic subtype, lymph node metastasis, and distant metastasis) were included. RSS1 was the best of the analysed models.ConclusionWe developed and validated a new RSS derived from previous meta-analyses for patients with PTC. This RSS seems to be superior to previously published systems.

Evaluation of thyroid nodules with coexistent Hashimoto’s thyroiditis according to various ultrasound-based risk stratification systems：A retrospective research

PurposesTo investigate the efficiency of Thyroid Imaging Reporting and Data System (TI-RADS) proposed by KWAK, the American College of Radiology, and the 2015 American Thyroid Association (ATA) guidelines for thyroid nodules with Hashimoto’s thyroiditis (HT) and to determine whether HT influence the diagnostic performance of these risk-stratification systems. MethodsA total of 101 nodules with HT and 101 nodules with non-HT were retrospectively analyzed by ultrasound-based diagnostic classifications and compared with histopathological results. The areas under the receiver operating characteristic curve (AUCs) were calculated for comparative analysis. ResultsIn the HT group, KWAK TI-RADS has the best sensitivity (91.67%), while ACR TI-RADS has the highest specificity (82.93%) and accuracy (81.19%). The AUCs of ACR TI-RADS, ATA guidelines, and KWAK TI-RADS were 0.844, 0.782, and 0.830, respectively. In the non-HT group, the sensitivity and specificity of three risk-stratification systems had no significant difference. The AUCs of ACR TI-RADS, ATA guidelines, and KWAK TI-RADS were 0.872, 0.839, and 0.874, respectively. No significant difference was found in diagnostic effectiveness of the same systems with both contexts. ConclusionsACR TI-RADS performed the most effective for thyroid nodules in HT, whereas KWAK TI-RADS was the best for those in non-HT. Both of TI-RADS (ACR and KWAK) provided higher diagnostic effectiveness than ATA guidelines in HT or in non-HT. Moreover, HT could not affect the diagnostic performance of these risk-stratification systems.

African Head and Neck Society Clinical Practice guidelines for thyroid nodules and cancer in developing countries and limited resource settings.

International thyroid nodule and cancer management guidelines generally fail to take into account potential limitations in diagnostic and treatment resources. Thyroid cancer specialists from the African Head and Neck Society and American Head & Neck Society Endocrine Section developed guidelines for diagnosis and management of thyroid nodules and cancer in low resource settings. Recommendations were based on literature review and expert opinion, with level of evidence defined. Using the ADAPTE process, diagnostic and treatment algorithms were adapted from the National Comprehensive Cancer Network (NCCN). Low resource settings were simulated by systematically removing elements such as availability of laboratory testing, hormone replacement, imaging, and cytopathology from NCCN guidelines. Successful management of thyroid nodules and cancer in low resource settings requires adaptation of treatment methodologies. These guidelines define specific scenarios where either more or less aggressive intervention for thyroid pathology may be advisable based on limited available resources.

Pattern-based vs. score-based guidelines using ultrasound features have different strengths in risk stratification of thyroid nodules.

To evaluate and compare the diagnostic performances between recently published pattern-based and score-based TIRADS according to the experience level of the performer. From July 2013 to January 2019, 8657 thyroid nodules in 8364 patients that had been cytopathologically diagnosed as benign or malignant were included (mean size, 22.0mm ± 12.1). Thyroid nodules were categorized into US-based final assessment categories and US-FNA indications of five recently published TIRADS. Radiologists performing the US examinations were divided into the experienced vs. inexperienced group. Diagnostic performances and unnecessary biopsy rates were calculated and compared between the five TIRADS, also the experienced vs. inexperienced group. Of the 8657 thyroid nodules, 6706 (77.5%) were benign and 1951 (22.5%) were malignant. Diagnostic performances for US-based final assessment categories showed higher sensitivity and NPV for EU-TIRADS (92.7% and 96.5%), while Kwak-TIRADS had higher specificity, PPV, accuracy, and AUC (89.6%, 68.0%, 86.5%, and 0.878; all p < 0.05, respectively). Diagnostic performances for US-FNA indications showed higher sensitivity and NPV for KTA/KSThR TIRADS (98.5% and 97.0%), while Kwak-TIRADS had higher specificity, PPV, accuracy, and AUC (70.3%, 46.6%, 74.5%, and 0.797; all p < 0.05, respectively). Unnecessary biopsy rates were the lowest in Kwak-TIRADS for both US categories and US-FNA indications (32.0% and 53.4%, p < 0.001). Similar trends were seen in both the experienced and inexperienced group. The currently published score-based guidelines for thyroid nodules have significantly higher specificity, PPV, accuracy, and AUC and lower unnecessary biopsy rates, whereas pattern-based guidelines have higher sensitivity and NPV, regardless of the level of experience of the performer. • For US-based final assessment categories, EU-TIRADS had higher sensitivity and NPV, while Kwak-TIRADS had higher specificity, PPV, accuracy, and AUC. • For US-FNA indications, KTA/KSThR TIRADS had higher sensitivity and NPV, while Kwak-TIRADS had higher specificity, PPV, accuracy, and AUC. • Similar trends were seen in diagnostic performances for both experienced and inexperienced groups.

2019 Practice guidelines for thyroid core needle biopsy: a report of the Clinical Practice Guidelines Development Committee of the Korean Thyroid Association.

Ultrasound-guided core needle biopsy (CNB) has been increasingly used for the pre-operative diagnosis of thyroid nodules. Since the Korean Society of the Thyroid Radiology published the ‘Consensus Statement and Recommendations for Thyroid CNB’ in 2017 and the Korean Endocrine Pathology Thyroid CNB Study Group published ‘Pathology Reporting of Thyroid Core Needle Biopsy’ in 2015, advances have occurred rapidly not only in the management guidelines for thyroid nodules but also in the diagnostic terminology and classification schemes. The Clinical Practice Guidelines Development Committee of the Korean Thyroid Association (KTA) reviewed publications on thyroid CNB from 1995 to September 2019 and updated the recommendations and statements for the diagnosis and management of thyroid nodules using CNB. Recommendations for the resolution of clinical controversies regarding the use of CNB were based on expert opinion. These practical guidelines include recommendations and statements regarding indications for CNB, patient preparation, CNB technique, biopsy-related complications, biopsy specimen preparation and processing, and pathology interpretation and reporting of thyroid CNB.

Concordance of Three International Guidelines for Thyroid Nodules Classified by Ultrasonography and Diagnostic Performance of Biopsy Criteria

ObjectiveTo investigate the concordance of three international guidelines: the Korean Thyroid Association/Korean Society of Thyroid Radiology, American Thyroid Association, and American College of Radiology for thyroid nodules classified by ultrasonography (US) and the diagnostic performance of simulated size criteria for malignant biopsies.Materials and MethodsA total of 2586 thyroid nodules (≥ 1 cm) were collected from two multicenter study datasets. The classifications of the thyroid nodules were based on three different guidelines according to US categories for malignancy risk, and the concordance rate between the different guidelines was calculated for the classified nodules. In addition, the diagnostic performance of criteria related to four different simulated biopsy sizes was evaluated.ResultsThe concordance rate of nodules classified as high- or intermediate-suspicion was high (84.1–100%), but low-suspicion or mildly-suspicious nodules exhibited relatively low concordance (63.8–83.8%) between the three guidelines. The differences in sensitivity, specificity, and accuracy between the guidelines were 0.7–19.8%, 0–40.9%, and 0.1–30.5%, respectively, when the original biopsy criteria were applied. The differences decreased to 0–5.9%, 0–10.9%, and 0.1–8.2%, respectively, when simulated, similar biopsy size criteria were applied. The unnecessary biopsy rate calculated with the original criteria (0–33.8%), decreased with the simulated biopsy size criteria (0–8.7%).ConclusionWe found a high concordance between the three guidelines for high- or intermediate-suspicion nodules, and the diagnostic performance of the biopsy criteria was approximately equivalent for each simulated size criterion. The difference in diagnostic performance between the three guidelines is mostly influenced by the various size thresholds for biopsies.

Can Clinical Presentation and Ultrasonography Predict the Risk of Malignancy in Thyroid Nodules

Background: Thyroid nodules are frequent occurrences. This study aims to evaluate the risk of malignancy based on the 2015 American Thyroid Association Management: Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer. Methods: In this cross-sectional study, ultrasonography and clinical manifestations were compared with pathology findings to predict the risk of malignancy in thyroid nodules. Assessment of the ultrasound findings was based on the criteria recommended by The 2015 American Thyroid Association Management Guidelines for Thyroid Nodules. For the evaluation of the association between clinical and ultrasound findings with histopathology results, we used the chi-square and Fisher’s exact tests. The relative risk and prediction of malignancy was assessed by multiple logistic regression analysis. Data analysis was performed by the SPSS19. The significance level was set at P<0.05. Results: From 130 patients with thyroid nodules, 110 (84.6%) were female. The mean age of participants was 46.1±11.5 years. Histopathology findings showed malignancy in 17.7% of the nodules, all of were papillary thyroid carcinoma. Multivariate logistic regression showed some of the ultrasonography parameters, absence of halo (P<0.001, OR=28), taller than wide shape (P=0.001, OR=18.3), nodule size more than 4 cm (P=0.04, OR=12.1), irregular margin (P=0.001, OR=10.06), solid or mixed composition (P=0.002, OR=8.1), hypoechoic (P=0.001, OR=4.5), lymph node positive (P=0.002, OR=4.3), positive calcification (P=0.03, OR=2.08), positive internal vascularity (P<0.001, OR=1.05), and intermediate/high level of suspicion (P=0.001, OR=12) could predict malignancy in patients with thyroid nodules. Conclusion: Based on increasing rate of thyroid cancer, in this study, the new and accurate ultrasound technique is recommended as alternative diagnostic method due non-invasive nature and lower cost used.

Thyroid Incidentalomas Detected on 18F-Fluorodeoxyglucose Positron Emission Tomography with Computed Tomography: Malignant Risk Stratification and Management Plan.

The aims of this study were to stratify the risk of malignancy in thyroid incidentalomas detected on 18F-fluorodeoxyglucose positron emission tomography with computed tomography (18F-FDG PET/CT) using ultrasound features according to guidelines for thyroid nodules and to develop a subsequent management plan. From a historical cohort of 96,942 consecutive patients who underwent 18F-FDG PET/CT between October 2008 and September 2015, 1342 patients with 1364 nodules underwent ultrasound evaluation for focal uptake in thyroid gland, with a final diagnosis made for 877 patients with 907 nodules, which were included in this study. Ultrasound images were retrospectively reviewed, and they were stratified according to the American Thyroid Association and Korean Thyroid Image Reporting and Data System guidelines. The calculated malignancy risks were compared with the estimated risks suggested by the guidelines. The overall malignancy risk of thyroid incidentalomas detected on 18F-FDG PET/CT was 54.7%. When stratified according to the American Thyroid Association guidelines, the malignancy risks of thyroid incidentalomas with high and intermediate suspicion (93.2% and 45.2%, respectively) were higher than those indicated in the guidelines. The malignancy risks of thyroid incidentalomas with low and very low suspicion (8.1% and 0%, respectively) were within the guideline ranges. These findings were also noted when thyroid incidentalomas were stratified according to the Korean Thyroid Image Reporting and Data System, and in a subgroup of nodules >1 cm. Ultrasound examinations can be used to stratify the malignancy risk of thyroid incidentalomas detected on 18F-FDG PET/CT. The risk of malignancy did not increase in thyroid incidentalomas with low and very low suspicion, indicating that only selective biopsies may be needed in these categories of thyroid incidentalomas.

Validation of the 2015 American Thyroid Association Management Guidelines for Thyroid Nodules With Benign Cytologic Findings in the Era of the Bethesda System.

The purpose of this study is to investigate follow-up strategies for cytologically benign thyroid nodules according to size and ultrasound (US) pattern according to the 2015 American Thyroid Association (ATA) guidelines in the era of the Bethesda system. This retrospective study included 1208 patients with 1230 nodules that were cytologically benign at initial fine-needle aspiration performed from June 2012 to December 2014. False-negative rates (FNRs) were calculated by considering nodule size and US pattern according to the 2015 ATA guidelines and were compared between nodules with the high-suspicion US pattern and nodules with the high- or intermediate-suspicion US patterns according to size. Twenty-five of the 1230 nodules (2.0%) were malignant. The FNRs were 5.1% (8/158) for nodules with the high-suspicion US pattern and 1.6% (17/1072) for nodules with other US patterns. With regard to nodule size, the FNRs were 3.2% (9/277) for nodules 3 cm or larger and 5.2% (6/115) for nodules 4 cm or larger. The FNRs of nodules with the high-suspicion pattern were not significantly higher than those of nodules with the high- or intermediate-suspicion patterns among nodules 2 cm or larger (2.5% vs 1.9%; p = 0.208), 3 cm or larger (3.4% vs 2.9%; p = 0.498), and 4 cm or larger (5.4% vs 3.8%; p = 0.353). Thyroid nodules with initial benign cytologic findings had a low malignancy rate in the era of the Bethesda system, regardless of US pattern and size. Therefore, any immediate diagnostic intervention may be discouraged in cytologically benign nodules.

Guideline Compliance in Surgery for Thyroid Nodules - A Retrospective Study.

Diagnostic guidelines for thyroid nodules focus on malignancy risk assessment to avoid unnecessary diagnostic operations. These guidelines recommend a combination of tests in form of a diagnostic algorithm. The present study analyzed the recommended algorithm and its implementation by different medical professionals. Preoperative diagnostic procedures, laboratory tests and histopathological findings of patients who underwent thyroid surgery between 2006 and 2013 were analyzed. The results were stratified by the assignation by specialized endocrinologists (ENP), general practitioners (GP) or Goethe-University Hospital Frankfurt (UKF). 677 patients were enrolled, of these 62% were assigned by UKF, 18.5% by an ENP and 19.5% by a GP. Ultrasonography rate was significantly higher in UKF (97.6%) compared to patients assigned by GP (90.9%, p<0.0001). Rates for fine-needle aspiration cytology ranged between 47.6% in UKF and 23.2% in ENP (p<0.0001). In over 93% of the patients an analysis of thyroid-stimulating hormone and triiodothyronine/thyroxin was realized. The overall malignancy rate was 11.82%. The malignancy rate was significantly higher if a FNA biopsy was performed (16.35 vs. 8.94%; p=0.0048). A higher malignancy rate could only be seen if the preoperative diagnostic workup included FNA. Besides this, the grade of algorithm adherence showed no effect on the malignancy rate.

The impact of Chinese guideline on the managements of patients with thyroid nodules and undergoing surgery

Objective To investigate the influence of Chinese guidelines for thyroid nodules and differentiated thyroid cancers on the diagnosis and treatment of thyroid nodule patients undergoing thyroid surgery in the PLA General Hospital. Methods A retrospective analysis was conducted on data of 2 243 thyroid nodule inpatients who were undergoing thyroid surgery and with their pathology results in 2011(before the guideline change, 1 013 patients)and in 2013(after the guideline change, 1 230 patients). The data of the changes of the baseline characteristics, diagnosis, constituent of thyroid nodule, distribution of benign thyroid nodule size were compared between 2011 and 2013. The differences of surgical managements of thyroid cancer were also studied. Results (1)A higher proportion of female patients was showed in 2013 group(75.61% vs 69.20%, P<0.01). The age of patients in 2013 group was significantly younger than that of 2011 group [(45.74±11.77 vs 47.43±11.87)years old, P<0.01]. (2)Thyroid stimulating hormone and ultrasound-guided aspiration biopsy were used more often after the guideline change(83.00% vs 65.55%, 47.95% vs 19.50% respectively, both P<0.01). And the proportion of benign nodules decreased gradually in the post-guideline period(32.20% vs 49.95%, P<0.01). The sizes of benign and malignant nodules were both showed a descending tendency [(2.487±0.861 vs 2.800±0.720)cm, (1.027±0.795 vs 1.186±0.964)cm respectively, both P<0.01]. (3)After the change of guidelines, the percentage of the options of total/near-total thyroidectomy, hemithyroidectomy with isthmusectomy, and central lymph node dissection for thyroid cancer were increased(respectively 31.29% vs 15.38%, 16.91% vs 7.69%, and 64.15% vs 50.50%, all P<0.01). Conclusion After Chinese guideline was introduced in 2012, the surgical management of thyroid nodules in our hospital had been followed more closely to the recommendations of the guidelines. (Chin J Endocrinol Metab, 2016, 32: 749-753) Key words: Thyroid nodule; Guidelines; Diagnosis; Therapy

New American Thyroid Association Sonographic Patterns for Thyroid Nodules Perform Well in Medullary Thyroid Carcinoma: Institutional Experience, Systematic Review, and Meta-Analysis.

The 2015 American Thyroid Association (ATA) thyroid nodule guidelines recommend selecting nodules for biopsy based on a sonographic pattern classification. These patterns were developed based on features of differentiated thyroid cancer. This study aimed to evaluate the performance and the inter-observer agreement of this classification system in medullary thyroid carcinoma (MTC). The medical records of all patients with MTC evaluated at the authors' institution between 1998 and 2014 were retrospectively reviewed. Only patients with presurgical thyroid ultrasound available for review were included in the study. Five independent reviewers assessed the stored ultrasound images for composition, echogenicity, margins, presence of calcifications, and extrathyroidal extension for each nodule. The presence of suspicious lymph nodes was also evaluated when presurgical lateral neck ultrasound was available for review. Each nodule was classified according to the ATA sonographic patterns. Inter-observer agreement was calculated for each sonographic feature and for the sonographic patterns. To validate the findings, a systematic review of the literature and meta-analysis on the sonographic features of MTC was conducted. In this institutional cohort, the inter-observer agreement for individual sonographic features was moderate to good (κ = 0.45-0.71), and for the ATA classification it was good (κ = 0.72). Ninety-seven percent (29/30) of the MTCs were classified in the intermediate or high suspicion patterns. A total of 249 MTCs were included in the meta-analysis. Based on pooled frequencies for solid composition and hypoechogenicity, >95% of MTCs would be classified at least in the intermediate suspicion pattern, warranting the lowest-size threshold for biopsy (≥1 cm). The sonographic patterns proposed by the ATA perform well in MTC, and inter-observer agreement is good to very good.

Less is More: Comparing the 2015 and 2009 American Thyroid Association Guidelines for Thyroid Nodules and Cancer.

The American Thyroid Association (ATA) has recently revised its guidance pertaining to thyroid nodules and follicular cell-derived thyroid cancer. The 2015 guidelines are massive in both scope and scale, with changes in the organizational approach to risk stratification of nodules and cancer, as well as multiple sections covering new material. This review highlights the major structural and organizational changes, focusing attention on the most dramatically changed recommendations, that is, those recommendations that clinicians will find striking because they call for significant divergence from prior clinical practice. The revised approach to thyroid nodule risk stratification is based on sonographic pattern, with an emphasis on pattern rather than growth in the long-term surveillance of nodules. Accumulating data have also been incorporated into an updated risk stratification scheme for thyroid cancer that increases the size of the low-risk pool, in part because low-volume lymph nodal metastases are now considered low risk. The most fundamentally altered recommendation is that lobectomy might be considered as the initial surgical approach for follicular cell-derived thyroid cancers from 1 to 4 cm in size. The underlying theme of the 2015 ATA guidelines is that "less is more." As these new recommendations are adopted, fewer fine-needle aspiration biopsies will need to be done, less extensive surgeries will become more common, less radioactive iodine will be used either for treatment or for diagnostics, and less stimulated thyroglobulin testing will be done. Mastery of these guidelines will help clinicians know when it is reasonable to do less, thus providing responsibly individualized therapy for their patients.

Thyroid nodule ultrasound: technical advances and future horizons.

Thyroid nodules are extremely common and the vast majority are non-malignant; therefore the accurate discrimination of a benign lesion from malignancy is challenging. Ultrasound (US) characterisation has become the key component of many thyroid nodule guidelines and is primarily based on the detection of key features by high-resolution US. The thyroid imager should be familiar with the strengths and limitations of this modality and understand the technical factors that create and alter the imaging characteristics. Specific advances in high-resolution US are discussed with reference to individual features of thyroid cancer and benign disease. Potential roles for three-dimensional thyroid ultrasound and computer-aided diagnosis are also considered. The second section provides an overview of current evidence regarding thyroid ultrasound elastography (USE). USE is a novel imaging technique that quantifies tissue elasticity (stiffness) non-invasively and has potential utility because cancers cause tissue stiffening. In recent years, there has been much research into the value of thyroid USE for distinguishing benign and malignant nodules. Preliminary findings from multiple pilot studies and meta-analyses are promising and suggest that USE can augment the anatomical detail provided by high-resolution US. However, a definite role remains controversial and is discussed.Teaching points • High-resolution US characterises thyroid nodules by demonstration of specific anatomical features • Technical advances heavily influence the key US features of thyroid nodules • Most papillary carcinomas appear stiffer than benign thyroid nodules on US elastography (USE) • Thyroid USE is controversial because of variation in the reported accuracies for malignancy • Combined grey-scale US/USE may lower the FNAC rate in benign nodules