The Thyroid Imaging Reporting and Data System (TIRADS) for ultrasound of the thyroid : a pratical approach

Transcription

1 The Thyroid Imaging Reporting and Data System (TIRADS) for ultrasound of the thyroid : a pratical approach Poster No.: C-2425 Congress: ECR 2015 Type: Educational Exhibit Authors: M. Ben Lassoued, B. Souissi, K. Hammami, A. Maalej, N. Toumi, H. Abid, S. Haddar, K. Ben Mahfoudh; Sfax/TN Keywords: Thyroid / Parathyroids, Ultrasound, Ultrasound-Colour Doppler, Diagnostic procedure, Neoplasia DOI: /ecr2015/C-2425 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 20

2 Learning objectives The classification system of the thyroid nodules (TN) TI-RADS (Thyroid Imaging Reporting and Data System) is rarely used. The aim of this work is to make this classification easier through a practical guide. Page 2 of 20

3 Background The widespread use of ultrasonography (US) has contributed to the increased detection of thyroid nodules. Thyroid US depicts nodules in up to 67% of the population. However, Less than 10% of these nodules are malignant. Although many reports have demonstrated malignant US features that necessitate USguided fine needle aspiration biopsy (FNAB), it was hard to decide which lesions should undergo FNAB because the same thyroid nodule may be classified in different ways with different guidelines. Therefore, it may be confusing to determine which guideline to use when deciding whether to perform FNAB in a thyroid nodule. Page 3 of 20

4 Findings and procedure details Recently, Horvath et al have suggested a reporting data system for thyroid lesions in stratifying the malignant risk of nodules. The author used the categorization system of US features in thyroid nodules and demonstrated the risk of malignancy in each category. This classification system is based on the Breast Imaging Reporting and Data System (BI-RADS), which was developed by the American College of Radiology. The BI-RADS has been designed to help standardize breast imaging reports, final assessments, and the management of breast lesions, resulting in better communication between clinicians and radiologists. Although several studies have suggested that TI-RADS helps avoid confusion among physicians and patients and reduces unnecessary benign cytological results, applying this approach is difficult in daily practice because of its complexity. In a study looking for novel approaches to overcome the complexity of TI-RADS, Kwak et al. developed a practical TIRADS approach to categorize thyroid nodules and stratify their malignant risk. Kwak et al. demonstrated that The following US features are significantly associated with thyroid cancer: solid component, hypoechogenicity, marked hypoechogenicity, microlobulated or irregular margins, microcalcifications, and taller-than-wide shape. As the number of suspicious US features increased, the fitted probability and risk of malignancy also increased. Risk stratification of thyroid malignancy by using the number of suspicious US features allows for a practical and convenient thyroid imaging reporting and data system. To further achieve a practical tool in the hands of sonographers in analysing thyroid nodules and to improve communication between radiologists and clinicians, Russ et al. proposed a TIRADS classification that was further modified after feedback from those who used it. Page 4 of 20

5 In our practice, we are using this modified classification to classify thyroid nodules and to decide those that necessitate US-guided fine needle aspiration biopsy. The TIRADS LEXIC: To each nodule, the radiologist has to specify its: 1. Shape ("taller-than-wide" (greater in its antero-posterior dimension than in its transverse dimension) and "wider-than-tall"). 2. Internal component (solid, mixed or cystic) 3. Margins (well circumscribed, lobulated or irregular ) 4.Echogenicity("hyperechogenicity", "marked hypoechogenicity"). "isoechogenicity", "hypoechogenicity" and Isoechogenicity was defined as an echogenicity similar to that of the adjacent healthy thyroid gland. A nodule was classified as "marked hypoechogenicity" if the echogenicity was less than that of the superficial surrounding neck muscles. 5.Evidence of calcifications (micro-calcifications (< 3 mm) and macrocalcifications (> 3 mm with acoustic shadowing)) 6. Stiffness Index Using the modified Russ classification, each nodule was classified into a TIRADS category (1, 2, 3, 4A, 4B and 5) based on the US features. TIRADS classification TIRADS 1: Normal thyroid US Page 5 of 20

6 TIRADS 2: Benin aspects # Simple cyst # Spongiform nodule # 'White Knight' aspect # Isolated macrocalcification # Typical sub acute thyroiditis TIRADS 3: Probably benin aspects # None of the highly suspicious aspects # Isoechogenic # Hyperechogenic TIRADS 4A: Low suspicious aspects # None of the highly suspicious aspects # Moderately hypoechogenic TIRADS 4B / 5: High suspicious aspects # Taller than wide shape # Irregular or microlobulated margins # Microcalcifications Page 6 of 20

7 # Marked hypoéchogenicity # High stiffness index with elastography (if available ) * 4B: 1 or 2 signs and no adenopathy * 5: 3 or more signs and/or adenopathy All studies show that most cancers were found in the TIRADS 3, 4 and 5 categories. When to perform FNAB? According to Russ, the decision to perform FNAB depends on the clinical context, the TIRADS classification and the evolution of the nodule. Clinical context: # External radiotherapy in childhood # A history in the first degrees of papillary carcinoma # family history of medullar carcinoma of the thyroid or NEM2 # Elevated basal calcitonin on two occasions # Adenopathy, metastasis # A personal or family history of Cowden disease, familial polyposis, Carney complex, McCune Albright. Suspicious Nodule: Volume increase > 20% and > 2mm in two diameters Page 7 of 20

8 Focal uptake in TEP - FDG TIRADS 4 or 5 Page 8 of 20

9 Images for this section: Fig. 1: Thyroid Cyst TIRADS 2 Page 9 of 20

10 Fig. 2: Spongiform nodule TIRADS 2 Page 10 of 20

11 Fig. 5: White Knight TIRADS 2 Page 11 of 20

12 Fig. 6: Isolated macrocalcification TIRADS 2 Page 12 of 20

13 Fig. 3: Isoechoechogenic TIRADS 3 Page 13 of 20

14 Fig. 4: Hypoechogenic nodule TIRADS 4A Page 14 of 20

15 Fig. 7: Taller-than-wide nodule TIRADS 4B Page 15 of 20

16 Fig. 8: Irregular margins TIRADS 4B Page 16 of 20

17 Fig. 9: Marked hypoechogenicity TIRADS 4B Page 17 of 20

18 Fig. 10: Microcalcifications TIRADS 4B Page 18 of 20

19 Conclusion TI-RADS score was first established by Horvath. Many others proposed a practical approach to make its application easier. All studies about TIRADS reliability had not been void of limitations, which include retrolective data collection and the fact that histology was not available for all of the thyroid nodules, as those with a benign cytology were not operated for ethical reasons. TIRADS gives us the ability to detect most thyroid carcinomas and to assert benign status with good reliability. Thus, it could lead to a significant decrease of the number of unnecessary FNABs. Page 19 of 20

20 References 1. Russ G, Royer B, Bigorgne C, Rouxel A, Bienvenu-Perrard M, et al. (2013) Prospective evaluation of thyroid imaging reporting and data system on 4550 nodules with and without elastography. Eur J Endocrinol 168: doi: /eje Horvath E, Majlis S, Rossi R, Franco C, Niedmann JP, et al. (2009) An ultrasonogram reporting system for thyroid nodules stratifying cancer risk for clinical management. J Clin Endocrinol Metab 94: doi: /jc Cooper DS, Doherty GM, Haugen BR, Kloos RT, Lee SL, et al. (2006) Management guidelines for patients with thyroid nodules and differentiated thyroid cancer. Thyroid 16: doi: /thy Rubaltelli L, Corradin S, Dorigo A, Stabilito M, Tregnaghi A, et al. (2009) Differential diagnosis of benign and malignant thyroid nodules at elastosonography. Ultraschall Med 30: doi: /s Park JY, Lee HJ, Jang HW, Kim HK, Yi JH, Lee W, et al. A proposal for a thyroid imaging reporting and data system for ultrasound features of thyroid carcinoma. Thyroid 2009;19: Kwak JY, Han KH, Yoon JH, Moon HJ, Son EJ, Park SH, et al. Thyroid imaging reporting and data system for US features of nodules: a step in establishing better stratification of cancer risk. Radiology 2011;260: Kim EK, Park CS, Chung WY, Oh KK, Kim DI, Lee JT, et al. New sonographic criteria for recommending fine-needle aspiration biopsy of nonpalpable solid nodules of the thyroid. AJR Am J Roentgenol 2002;178: Page 20 of 20