Lancet (2014) 384(9957): 1848:184858. Radiology. Thyroid imaging reporting and data system (TI-RADS)refers to any of several risk stratification systems for thyroid lesions, usually based on ultrasound features, with a structure modelled off BI-RADS. And because thyroid cancer is often diagnosed in a persons late 30s or 40s, most of us are often diagnosed after the symptoms have already begun. The cost of seeing 100 patients and only doing FNA on TR5 is at least NZ$100,000 (compared with $60,000 for seeing all patients and randomly doing FNA on 1 in 10 patients), so being at least NZ$20,000 per cancer found if the prevalence of thyroid cancer in the population is 5% [25]. The diagnostic schedule of CEUS could get better diagnostic performance than US in the differentiation of thyroid nodules. The management guidelines may be difficult to justify from a cost/benefit perspective. Thyroid nodules are solid or fluid-filled lumps that form within your thyroid, a small gland located at the base of your neck, just above your breastbone. By CEUS-TIRADS diagnostic model combining CEUS with C-TIRADS, a total of 127 cases were determined as malignancy (111 were malignant and 16 were benign) and 101 were diagnosed as benign ones (5 were malignant and 96 were benign). TIRADS 5: probably malignant nodules (malignancy >80%). Your health care provider will examine your neck to feel for changes in your thyroid, such as a lump (nodule) in the thyroid. official website and that any information you provide is encrypted This study aimed to assess the performance and costs of the American College of Radiology (ACR) Thyroid Image Reporting And Data System (TIRADS), by first looking for any important issues in the methodology of its development, and then illustrating the performance of TIRADS for the initial decision for or against FNA, compared with an imagined doi: 10.1210/jendso/bvaa031. The performance of any diagnostic test in this group has to be truly exceptional to outperform random selection and accurately rule in or rule out thyroid cancer in the TR3 or TR4 groups. We aimed to assess the performance and costs of the American College of Radiology Thyroid Image Reporting And Data System (ACR-TIRADS). TIRADS ( T hyroid I maging R eporting and D ata S ystem) is a 5-point scoring system for thyroid nodules on ultrasound, developed by the American College of Radiology ( hence also termed as ACR- TIRADS). In 2017, the Thyroid Imaging Reporting and Data System (TI-RADS) Committee of the American College of Radiology (ACR) published a white paper that presented a new risk-stratification system for classifying thyroid nodules on the basis of their appearance at ultrasonography (US). The US follow-up is mainly recommended for the smaller TR3 and TR4 nodules, and the prevalence of thyroid cancer in these groups in a real-world population with overall cancer risk of 5% is low, likely<3%. It is important to validate this classification in different centres. Careers. A 38-year-old woman with a nodule in the right-lobe of her thyroid gland. For the calculations, we assume an approximate size distribution where one-third of TR3 nodules are25 mm and half of TR4 nodules are15 mm. It would be unfair to add these clinical factors to only the TIRADS arm or only to the clinical comparator arm, and they would cancel out if added to both arms, hence they were omitted. TR5 in the data set made up 16% of nodules, in which one-half of the thyroid cancers (183/343) were found. In CEUS analysis, it reflected as later arrival time, hypo-enhancement, heterogeneous and centripetal enhancement, getting a score of 4 in the CEUS model. All of the C-TIRADS 4 nodules were re-graded by CEUS-TIRADS. This assumption is obviously not valid and favors TIRADS management guidelines, but we believe it is helpful for clarity and illustrative purposes. That particular test is covered by insurance and is relatively cheap. Now, the first step in T3N treatment is usually a blood test. In 2009, Park et al. The sensitivity, specificity, and accuracy of CEUS were 78.7%, 87.5%, and 83.3% respectively. Other similar systems are in use internationally (eg, Korean-TIRADS [14] and EU-TIRADS [15]). We assessed a hypothetical clinical comparator where 1 in 10 nodules are randomly selected for fine needle aspiration (FNA), assuming a pretest probability of clinically important thyroid cancer of 5%. 4. Epub 2021 Oct 28. Clinicians should be using all available data to arrive at an educated estimate of each patients pretest probability of having clinically significant thyroid cancer and use their clinical judgment to help advise each patient of their best options. Cheng H, Zhuo SS, Rong X, Qi TY, Sun HG, Xiao X, Zhang W, Cao HY, Zhu LH, Wang L. Int J Endocrinol. In the case of thyroid nodules, there are further challenges. J. Endocrinol. The specificity of TIRADS is high (89%) but, perhaps surprisingly, is similar to randomly selecting of 1 in 10 nodules for FNA (90%). To show the best possible performance of ACR TIRADS, we are comparing it to clinical practice in the absence of TIRADS or other US thyroid nodule stratification tools, and based on a pretest probability of thyroid cancer in a nodule being 5%, where 1 in 10 nodules are randomly selected for FNA. 6. The health benefit from this is debatable and the financial costs significant. With the right blood tests, you can see if you have a thyroid nodule, and if so, you can treat it with radioactive iodine. As it turns out, its also very accurate and detailed. Many studies have not found a clear size/malignancy correlation, and where it has been found, the magnitude of the effect is modest. Disclaimer. Friedrich-Rust M, Meyer G, Dauth N et-al. K-TIRADS category was assigned to the thyroid nodules. Any additional test has to perform exceptionally well to surpass this clinicians 95% negative predictive performance, without generating false positive results and consequential harm. 2022 Jun 7;28:e936368. Therefore, 60% of patients are in the middle groups (TR3 and TR4), where the US features are less discriminatory. In: Thyroid 26.1 (2016), pp. 4b - Suspicious nodules (10-50% risk of malignancy) Score of 2. The test may cycle back between being used on training and validation data sets to allow for improvements and retesting. Shin JH, Baek JH, Chung J, et al. ADVERTISEMENT: Radiopaedia is free thanks to our supporters and advertisers. Russ G, Royer B, Bigorgne C et-al. We are here imagining the consequence of 100 patients presenting to the thyroid clinic with either a symptomatic thyroid nodule (eg, a nodule apparent to the patient from being palpable or visible) or an incidentally found thyroid nodule. PLoS ONE. doi: 10.1111/j.1754-9485.2009.02060.x The category definitions were similar to BI-RADS, based on the risk of malignancy depending on the presence of suspicious ultrasound features: The following features were considered suspicious: The study included only nodules 1 cm in greatest dimension. Following ACR TIRADS management guidelines would likely result in approximately one-half of the TR3 and TR4 patients getting FNAs ((0.537)+(0.323)=25, of total 60), finding up to 1 cancer, and result in 4 diagnostic hemithyroidectomies for benign nodules (250.20.8=4). The proportion of malignancy in Bethesda III nodules confirmed by surgery were significantly increased in proportion relative to K-TIRADS with 60.0% low suspicion, 88.2% intermediate suspicion, and 100% high suspicion nodules (p < 0.001). Such a study should also measure any unintended harm, such as financial costs and unnecessary operations, and compare this to any current or gold standard practice against which it is proposed to add value. We have also estimated the likely costs associated with using the ACR TIRADS guidelines, though for simplicity have not included the costs of molecular testing for indeterminate nodules (which is not readily available in the New Zealand public health system) nor any US follow-up and associated costs. J. Clin. Refer to separate articles for the latest systems supported by various professional societies: A TI-RADS was first proposed by Horvath et al. We first estimate the performance of ACR TIRADS guidelines recommended approach to the initial decision to perform FNA, by using TR1 or TR2 as a rule-out test, or using TR5 as a rule-in test because applying TIRADS at the extremes of pretest cancer risk (TR1 and TR2 for lowest risk, and TR5 for highest risk), is most likely to perform best. Castellana M, Castellana C, Treglia G, Giorgino F, Giovanella L, Russ G, Trimboli P. Oxford University Press is a department of the University of Oxford. To establish a CEUS-TIRADS diagnostic model to differentiate thyroid nodules (C-TIRADS 4) by combining CEUS with Chinese thyroid imaging reporting and data system (C-TIRADS). These patients are not further considered in the ACR TIRADS guidelines. 2022 Jan 6;2022:5623919. doi: 10.1155/2022/5623919. The PubMed wordmark and PubMed logo are registered trademarks of the U.S. Department of Health and Human Services (HHS). The ROC curves of C-TIRADS, CEUS, and CEUS-TIRADS of 228 nodules in the diagnostic model. 2022 Jun 30;12:840819. doi: 10.3389/fonc.2022.840819. 5. If you assume that FNA is done as per reasonable application of TIRADS recommendations (in all patients with TR5 nodules, one-half of patients with TR4 nodules and one-third of patients with TR3 nodules) and the proportion of patients in the real world have roughly similar proportion of TR nodules as the data set used, then 100 US scans would result in FNAs of about one-half of all patients scanned (of data set, 16% were TR5, 37% were TR4, and 23% were TR3, so FNA number from 100 scans=16+(0.537)+(0.323)=42). Tom James Cawood, Georgia Rose Mackay, Penny Jane Hunt, Donal OShea, Stephen Skehan, Yi Ma, TIRADS Management Guidelines in the Investigation of Thyroid Nodules; Illustrating the Concerns, Costs, and Performance, Journal of the Endocrine Society, Volume 4, Issue 4, April 2020, bvaa031, https://doi.org/10.1210/jendso/bvaa031. Your email address will not be published. Required fields are marked *. Unable to load your collection due to an error, Unable to load your delegates due to an error. For every 100 FNAs performed, about 30 are inconclusive, with most (eg, 20% of the original 100) remaining indeterminate after repeat FNA and requiring diagnostic hemithyroidectomy. Sometimes a physician may refer you to a specialist (doctor) at a clinic that specializes in thyroid cancer. The following article describes the initial iterations proposed by individual research groups, none of which gained widespread use. Please enable it to take advantage of the complete set of features! Well, there you have it. Thyroid imaging reporting and data system for US features of nodules: a step in establishing better stratification of cancer risk. Diag (Basel) (2021) 11(8):137493. doi: 10.12659/MSM.936368. The cost-effective diagnosis or exclusion of consequential thyroid cancer is an everyday problem faced by all thyroid clinicians. To further enhance the performance of TIRADS, we presume that patients present with only 1 TR category of thyroid nodules. Outlook. For this, we do not take in to account nodule size because size is not a factor in the ACR TIRADS guidelines for initial FNA in the TR1 and TR2 categories (where FNA is not recommended irrespective of size) or in the TR5 category (except in TR5 nodules of0.5 cm to<1.0 cm, in which case US follow-up is recommended rather than FNA). 5 The modified TI-RADS was composed of seven ultrasound features in identifying benign and malignant thyroid nodules, such as the nodular texture, nodular However, if the concern is that this might miss too many thyroid cancers, then this could be compared with the range of alternatives (ie, doing no tests or doing many more FNAs). Current thyroid cancer trends in the United States, Association between screening and the thyroid cancer epidemic in South Korea: evidence from a nationwide study, 2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: the American Thyroid Association Guidelines Task Force on Thyroid Nodules and Differentiated Thyroid Cancer, Thyroid ultrasound and the increase in diagnosis of low-risk thyroid cancer, Korean Society of Thyroid Radiology (KSThR) and Korean Society of Radiology, Ultrasonography diagnosis and imaging-based management of thyroid nodules: revised Korean Society of Thyroid Radiology Consensus Statement and Recommendations, European Thyroid Association Guidelines for Ultrasound Malignancy Risk Stratification of Thyroid Nodules in Adults: the EU-TIRADS, Multiinstitutional analysis of thyroid nodule risk stratification using the American College of Radiology Thyroid Imaging Reporting and Data System, The Bethesda System for reporting thyroid cytopathology: a meta-analysis, The role of repeat fine needle aspiration in managing indeterminate thyroid nodules, The indeterminate thyroid fine-needle aspiration: experience from an academic center using terminology similar to that proposed in the 2007 National Cancer Institute Thyroid Fine Needle Aspiration State of the Science Conference. The provider may also ask about your risk factors, such as past exposure to radiation and a family history of thyroid cancers. The area under the curve was 0.753. Before Unauthorized use of these marks is strictly prohibited. Those wishing to continue down the investigative route could then have US, using TIRADS or ATA guidelines or other measures to offer some relative risk-stratification. Russ G, Bonnema SJ, Erdogan MF, Durante C, Ngu R, Leenhardt L. Middleton WD, Teefey SA, Reading CC, et al. NCI Thyroid FNA State of the Science Conference, The Bethesda System for reporting thyroid cytopathology, ACR Thyroid Imaging, Reporting and Data System (TI-RADS): white paper of the ACR TI-RADS Committee, Thyroid nodule size at ultrasound as a predictor of malignancy and final pathologic size, Impact of nodule size on malignancy risk differs according to the ultrasonography pattern of thyroid nodules, TIRADS management guidelines in the investigation of thyroid nodules; an illustration of the concerns, costs and performance, Thyroid nodules with minimal cystic changes have a low risk of malignancy, [The Thyroid Imaging Reporting and Data System (TIRADS) for ultrasound of the thyroid], Malignancy risk stratification of thyroid nodules: comparison between the Thyroid Imaging Reporting and Data System and the 2014 American Thyroid Association Management Guidelines, Validation and comparison of three newly-released Thyroid Imaging Reporting and Data Systems for cancer risk determination, Machine learning-assisted system for thyroid nodule diagnosis, Automatic thyroid nodule recognition and diagnosis in ultrasound imaging with the YOLOv2 neural network, Using artificial intelligence to revise ACR TI-RADS risk stratification of thyroid nodules: diagnostic accuracy and utility, A multicentre validation study for the EU-TIRADS using histological diagnosis as a gold standard, Comparison among TIRADS (ACR TI-RADS and KWAK- TI-RADS) and 2015 ATA Guidelines in the diagnostic efficiency of thyroid nodules, Prospective validation of the ultrasound based TIRADS (Thyroid Imaging Reporting And Data System) classification: results in surgically resected thyroid nodules, Diagnostic performance of practice guidelines for thyroid nodules: thyroid nodule size versus biopsy rates, Comparison of performance characteristics of American College of Radiology TI-RADS, Korean Society of Thyroid Radiology TIRADS, and American Thyroid Association Guidelines, Performance of five ultrasound risk stratification systems in selecting thyroid nodules for FNA. A meta-analysis, This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs licence (, Mitoguardin2 is Associated with Hyperandrogenism and Regulates Steroidogenesis in Human Ovarian Granulosa Cells, Factors Associated with Diabetes Distress among Patients with Poorly Controlled Type 2 Diabetes, Serum adiponectin and leptin is not related to skeletal muscle morphology and function in young women, Association Between Metabolic Syndrome Inflammatory Biomarkers and COVID-19 Severity, Long-term outcome of body composition, ectopic lipid and insulin resistance changes with surgical treatment of acromegaly, Volume 7, Issue 4, April 2023 (In Progress), The Journal of Clinical Endocrinology & Metabolism, https://www.uptodate.com/contents/diagnostic-approach-to-and-treatment-of-thyroid-nodules, https://doi.org/10.6084/m9.figshare.11640168.v, http://creativecommons.org/licenses/by-nc-nd/4.0/, Receive exclusive offers and updates from Oxford Academic, 1 in 10 nodules having FNA, assuming pretest probability of cancer of 5%, Negative test being TR1 or TR2; positive test meaning TR3, TR4, or TR5, Positive test meaning TR5; negative test meaning TR1-4, Positive test meaning TR5, TR4 above size cutoff and TR3 above size cutoff; negative test meaning TR1, TR2, TR3 Below Size Cutoff or TR4 below size cutoff, Positive Test Meaning TR5, TR4 Above Size Cutoff and TR3 Above Size Cutoff; negative test meaning TR1, TR2, TR3 below size threshold or TR4 below size cutoff. There are inherent problems with studies addressing the issue such as selection bias at referral centers and not all nodules having fine needle aspiration (FNA). Data sets with a thyroid cancer prevalence higher than 5% are likely to either include a higher proportion of small clinically inconsequential thyroid cancers or be otherwise biased and not accurately reflect the true population prevalence. In a patient with normal life expectancy, a biopsy should be performed for nodules >1cm regardless of the ACR TI-RADS risk category. EU-TIRADS 1 category refers to a US examination where no thyroid nodule is found; there is no need for FNAB. Attempts to compare the different TIRADS systems on data sets that are also not reflective of the intended test population are similarly flawed (eg, malignancy rates of 41% [29]). Ultimately, most of these turn out to be benign (80%), so for every 100 FNAs, you end up with 16 (1000.20.8) unnecessary operations being performed. Thyroid surgery, Microvascular reconstruction, Neck surgery, Reconstructive surgery, Facial reconstruction, Parathyroid. Clinical Application of C-TIRADS Category and Contrast-Enhanced Ultrasound in Differential Diagnosis of Solid Thyroid Nodules Measuring 1 cm. The more important test metric for diagnosing a disease is the specificity, where a positive test helps rule-in the disease. Department of Endocrinology, Christchurch Hospital. The 2 examples provide a range of performance within which the real test performance is likely to be, with the second example likely to provide TIRADS with a more favorable test performance than in the real world. Zhonghua Yi Xue Za Zhi. Whilst the details of the design of the final validation study can be debated, the need for a well-designed validation study to determine the test characteristics in the real-world setting is a basic requirement of any new test. Whilst we somewhat provocatively used random selection as a clinical comparator, we do not mean to suggest that clinicians work in this way. Thyroid nodules come to clinical attention when noted by the patient; by a clinician during routine physical examination; or during a radiologic procedure, such as carotid ultrasonography, neck or chest computed tomography (CT), or positron emission tomography (PET) scanning. ectomy, Parotid gland surgery, Transoral laser microsurgery, Transoral robotic surgery, Oral surgery, Parotid gland tumor, Skin cancer, Tonsil cancer, Throat cancer, Salivary gland tumor, Salivary gland cancer, Thyroid nodule, Head and neck cancer, Laryngeal cancer, Tongue . Hong MJ, Na DG, Baek JH, Sung JY, Kim JH. They will want to know what to do with your nodule and what tests to take. Whilst our findings have illustrated some of the shortcomings of ACR TIRADS guidelines, we are not able to provide the ideal alternative. Thyroid Nodule Characterization: How to Assess the Malignancy Risk. We have detailed the data set used for the development of ACR TIRADS [16] in Table 1, plus noted the likely cancer rates in the real world if one assumes that the data set cancer prevalence (10.3%) is double that in the population upon which the test is intended to be used (pretest probability of 5%). I have some serious news about my thyroid nodules today. Objective: To determine whether the size of thyroid nodules in ACR-TIRADS ultrasound categories 3 and 4 is correlated with the Bethesda cytopathology classification. Methodologically, the change in the ACR-TIRADS model should now undergo a new study using a new training data set (to avoid replicating any bias), before then undergoing a validation study. Its not something that happens every day, but every day. Reference article, Radiopaedia.org (Accessed on 05 Mar 2023) https://doi.org/10.53347/rID-21448. 2013;168 (5): 649-55. no financial relationships to ineligible companies to disclose. Become a Gold Supporter and see no third-party ads. The consequences of these proportions are highly impactful when considering the real-world performance of ACR-TIRADS. PPV was poor (20%), NPV was no better than random selection, and accuracy was worse than random selection (65% vs 85%). This approach likely performs better than randomly selecting 1 in 10 nodules for FNA, but we intentionally made assumptions that would favor the performance of ACR TIRADS to illustrate that if a poor clinical comparator cannot clearly be beaten, then the clinical value that such new systems bring is correspondingly poor. PMC The problem is that many people dont know that they have a thyroid nodule, so they dont know how to treat it. The truth is, most of us arent so lucky as to be diagnosed with all forms of thyroid cancer, but we do live with the results of it. The probability of malignancy was based on an equation derived from 12 features 2. These publications erroneously add weight to the belief that TIRADS is a proven and superior model for the investigation of thyroid nodules. Horvath E, Majlis S, Rossi R et-al. FNA, fine-needle aspiration; US, ultrasound; CEUS, contrast-enhanced ultrasound; C-TIRADS, Chinese imaging reporting and data system. Full data including 95% confidence intervals are given elsewhere [25]. (2017) Radiology. In rare cases, they're cancerous. Thus, the absolute risk of missing important cancer goes from 5% (with no FNAs) to 2.5% using TIRADS and FNA of all TR5, so NNS=100/2.5=40. The results were compared with histology findings. EU-TIRADS 2 category comprises benign nodules with a risk of malignancy close to 0%, presented on sonography as pure/anechoic cysts ( Figure 1A) or entirely spongiform nodules ( Figure 1B ). Keywords: Thus, the absolute risk of missing important cancer goes from 4.5% to 2.5%, so NNS=100/2=50. Another clear limitation of this study is that we only examined the ACR TIRADS system. Tirads 5 thyroid gland: is a thyroid gland with 5 or more lesions, the rate of malignancy accounts for 87.5%. . It is limited by only being an illustrative example that does not take clinical factors into account such as prior radiation exposure and clinical features. Bethesda, MD 20894, Web Policies The vast majority of nodules followed-up would be benign (>97%), and so the majority of FNAs triggered by US follow-up would either be benign, indeterminate, or false positive, resulting in more potential for harm (16 unnecessary operations for every 100 FNAs). Now you can go out and get yourself a thyroid nodule. We then compare the diagnosis performance of C-TIRADS, CEUS, and CEUS-TIRADS by sensitivity, specificity, and accuracy. The common first step when you have a thyroid nodule is to go to your health care provider and get a referral. That particular test is covered by insurance and is relatively cheap. The prevalence of incidental thyroid cancer at autopsy is around 10% [3]. These nodules are relatively common and are usually harmless, but there is a very low risk of thyroid cancer. The authors stated that TI-RADS 4 and 5 nodules must be biopsied. The summary of test performance of random selection, ACR TIRADS as a rule-out test, ACR TIRADS as a rule-in test, and ACR TIRADS applied across all TIRADS categories are detailed in Table 2, and the full data, definitions, and calculations are given elsewhere [25]. Would you like email updates of new search results? Thyroid nodules are lumps that can develop on the thyroid gland. Quite where the cutoff should be is debatable, but any cutoff below TR5 will have diminishing returns and increasing harms. All of the C-TIRADS 4 nodules were re-graded by CEUS-TIRADS. TIRADS does not perform to this high standard. Second, the proportion of patients in the different ACR TIRADS (TR) categories may, or may not, reflect the real-world population (Table 1). As noted previously, we intentionally chose the clinical comparator to be relatively poor and not a fair reflection of real-world practice, to make it clearer to what degree ACR TIRADS adds value. The more carefully one looks for incidental asymptomatic thyroid cancers at autopsy, the more are found [4], but these do not cause unwellness during life and so there is likely to be no health benefit in diagnosing them antemortem. Copyright 2022 Zhu, Chen, Zhou, Ma and Huang. -, Fresilli D, David E, Pacini P, Del Gaudio G, Dolcetti V, Lucarelli GT, et al. Treatment of patients with the left lobe of the thyroid gland, tirads 3 However, the ACR TIRADS flow chart with its sharp cutoffs conveys a degree of certainty that may not be valid and may be hard for the clinician to resist. Very probably benign nodules are those that are both. Thyroid radiology practice has an important clinical role in the diagnosis and non-surgical treatment of patients with thyroid nodules, and should be performed according to standard practice guidelines for proper and effective clinical care. It has been retrospectively applied to thyroidectomy specimens, which is clearly not representative of the patient presenting with a thyroid nodule [34-36], and has even been used on the same data set used for TIRADS development, clearly introducing obvious bias [32, 37]. Therefore, the rates of cancer in each ACR TIRADS category in the data set where they used four US characteristics can no longer be assumed to be the case using the 5 US characteristics plus the introduction of size cutoffs. For those that also have 1 or more TR3, TR4, or TR5 nodules on their scan, they cannot have thyroid cancer ruled out by TIRADS because the possibility that their non-TR1/TR2 nodules may be cancerous is still unresolved. However, the consequent management guidelines are difficult to justify at least on a cost basis for a rule-out test, though ACR TIRADS may provide more value as a rule-in test for a group of patients with higher cancer risk. Anderson TJ, Atalay MK, Grand DJ, Baird GL, Cronan JJ, Beland MD. If a clinician does no tests and no FNAs, then he or she will miss all thyroid cancers (5 people per 100). No focal lesion. At the time the article was last revised Yuranga Weerakkody had Second, we then apply TIRADS across all 5 nodule categories to give an idea how TIRADS is likely to perform overall. These final validation sets must fairly represent the population upon which the test is intended to be applied because the prevalence of the condition in the test population will critically influence the test performance, particularly the positive predictive value (PPV) and negative predictive value (NPV). The optimal investigation and management of the 84% of the population harboring the remaining 50% of cancer remains unresolved. Interobserver Agreement of Thyroid Imaging Reporting and Data System (TIRADS) and Strain Elastography for the Assessment of Thyroid Nodules.