Sonographic differentiation of benign and malignant thyroid nodules: Prospective study

Transcription

1 Sonographic differentiation of benign and malignant thyroid nodules: Prospective study Poster No.: C-1720 Congress: ECR 2010 Type: Scientific Exhibit Topic: Head and Neck Authors: D. W. Kim, Y. H. Lee; Busan/KR Keywords: thyroid, nodule, ultrasound DOI: /ecr2010/C-1720 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 Purpose This prospective study was designed to evaluate diagnostic efficacy for differentiation of benign and malignant thyroid nodules using thyroid ultrasound (US). Methods and Materials Materials From January 2008 to June 2008, one radiologist performed thyroid US and made a prospective US diagnosis of nodular thyroid disease in 726 patients (612 women, 114 men; mean age, 51.1 ± 14.3 years (standard deviation)) who underwent their first thyroid US in our hospital. Among them, 195 patients (166 women, 29 men; mean age, 48.1 ± 12.4 years) with thyroid nodules larger than 5 mm in maximum diameter and cytologically diagnosed by a consecutive US-FNAB following the first thyroid US, were enrolled in this study. Only one thyroid nodule, the one showing the highest likelihood for the malignancy on thyroid US was included for each patient, in order to avoid bias, as a US diagnosis of a nodule could affect the US diagnosis of another nodule in the same or opposite thyroid lobe. Inclusion criteria for the sonographic features of the thyroid nodule US characteristics of malignancy marked hypoechogenecity an irregular margin microcalcifications a taller-than-wide shape associated lymphadenopathy (Figure 1) on page 4 Marked hypoechogenicity was defined as the same or decreased echogenicity, as compared with the strap muscle. An irregular margin included an ill-defined margin, microlobulation or a speculated margin, and perithyroidal infiltration. Page 2 of 20

3 An ill-defined margin was defined as a poorly demarcated margin of greater than 50 % on the border of a nodule; microlobulation was defined as the presence of many small lobules on the surface of a nodule. Microcalcifications were defined as tiny, hyperechoic foci with no comet-tail artifact and no posterior shadow. A taller-than-wide shape was defined as being greater in the anteroposterior diameter of the nodule than in the transverse diameter of the nodule. US characteristics of a benign nodule ovoid or flat shape isoechogenicity a smooth margin peripheral vascularity 'Borderline' US characteristics of a thyroid nodule hypoechogenicity centrally predominant vascularity macrocalcifications. Criteria for prospective US diagnosis of a thyroid nodule (Figure 2) on page 5 Five categories of thyroid US for classification of thyroid nodules 'suggestive for malignancy' (Figure 3) on page 5 'suspicious for malignancy' (Figure 4) on page 6 'indeterminate' (Figure 5) on page 7 'suspicious for benign' (Figure 6) on page 8 'suggestive for benign' (Figure 7) on page 9 US-FNAB was performed on the nodule that showed the greatest likelihood of being a thyroid malignancy. Only one sampling was obtained for each thyroid nodule, without administration of local anesthesia. US-FNAB was not performed on other thyroid nodules suspected of being benign lesions on thyroid US, due to the fact that selection of a nodule for US-FNAB was based primarily on US features rather than nodule size. All 195 patients with nodule(s) (n = 195: size range, from 0.5 to 8.2 cm; mean size, 1.52 cm ± 1.1 cm) underwent US-FNAB. We retrospectively compared prospective US diagnoses and cytopathologic results. Thyroid nodules depicted on thyroid US as 'suspicious for malignancy' and 'suggestive for Page 3 of 20

4 malignancy' were classified as positive, and thyroid nodules diagnosed as 'suspicious for benign' or 'suggestive for benign' were classified as negative. Thyroid nodules diagnosed as 'indeterminate' on thyroid US were excluded in determination of the diagnostic efficacy of thyroid US. Images for this section: Page 4 of 20

5 Fig. 1: Metastatic lymphadenopathy of PTC in perithyroidal area. Transverse US image in a 27-year-old woman shows associated lymph nodes (arrows) with intranodal cystic components along both tracheoesophageal grooves in the level of upper trachea. Fig. 2: Prospective US diagnosis of thyroid nodule Page 5 of 20

6 Fig. 3: 'Suggestive for malignancy'. Longitudinal US image of a papillary thyroid carcinoma in a 42-year-old woman shows marked hypoechogenicity, an irregular margin, microcalcifications, and a taller-than-wide shape for the nodule. Page 6 of 20

7 Fig. 4: 'Suspicious for malignancy'. Longitudinal US image of a papillary thyroid carcinoma in a 42-year-old woman shows marked hypoechogenicity, a smooth margin and an ovoid shape. Page 7 of 20

8 Fig. 5: 'Indeterminate'. Transverse US image of nodular hyperplasia in a 60-year-old woman shows macrocalcification in the peripheral portion of the nodule. The patient underwent right lobectomy of the thyroid, despite benign cytology on US-FNAB, for pathologic confirmation. Page 8 of 20

9 Fig. 6: 'Suspicious for benign'. Longitudinal US image of a benign nodule in a 57-yearold woman shows isoechogenicity and a smooth margin. Page 9 of 20

10 Fig. 7: 'Suggestive for benign'. Longitudinal US image of a benign nodule in a 46-yearold woman shows an ovoid shape, isoechogenicity, a smooth margin, and peripheral vascularity. Page 10 of 20

11 Results Incidence of US features in 195 thyroid nodules (Figure 1) on page 'suggestive for malignancy' (n = 52) 'suspicious for malignancy' (n = 16) 'indeterminate' (n = 23) 'suspicious for benign' (n = 19) 'suggestive for benign' (n = 85) Thyroid surgery was performed in 73 patients (65 women, 8 men; mean age, 48.2 years) as a result of malignant cytology (n = 51), a positive US diagnosis despite a benign cytology result on consecutive US-FNAB (n = 2), 'indeterminate for malignancy' cytology (n = 11), presence of a large palpable mass with a benign cytology (n = 6), and due to patient request (n = 3). Repeated US-FNAB was performed on thyroid nodules when cytological results of the first US-FNAB were 'indeterminate for malignancy' (n = 8) or inadequate (n = 18). Twelve patients who demonstrated malignant cytology after USFNAB refused thyroid surgery in our hospital and were transferred to other hospitals due to patient request, or for other reasons. Patients with nodules (n = 96) who were assigned to 'benign' US categories and who showed benign cytology underwent follow-up with repeated thyroid US examinations after at least six months. On thyroid US, 45 patients showed a solitary thyroid nodule, and 150 patients had two or more thyroid nodules. Correlation of the US diagnosis with cytopathologic results (Figure 2) on page 13 When nodules (n = 23) assigned as 'indeterminate' on thyroid US were excluded, there were 61 true positives, seven false positives, 98 true negatives, and six false negatives for diagnoses determined using thyroid US. Thyroid US for differentiation of a malignancy from a benign lesion sensitivity: 91.4% specificity: 93.3% positive predictive value: 89.7% negative predictive value: 94.2% accuracy: 92.4% Diagnostic efficacy of thyroid US using 5-category system was determined as the excellent value by receiver operating curve (ROC) analysis (Az (area under the ROC curve) value, 0.957) (Figure 3) on page 13 Page 11 of 20

12 Diagnostic indices for individual US features of malignant and benign thyroid nodules (Figure 4) on page 14 All of the nodules assigned as 'suggestive for malignancy' on thyroid US, were confirmed as papillary thyroid carcinomas (PTCs), with the exception of one medullary thyroid carcinoma (MTC) and one benign lesion that was confirmed as spontaneous collapse of a previously benign cystic nodule (Figure 5). on page 15However, 16 nodules assigned as 'suspicious for malignancy' on thyroid US included 10 PTCs, three pseudonodules related to thyroiditis, two benign lesions confirmed as spontaneous collapse of a previously benign cystic nodule, and one focal thyroiditis. For 85 nodules assigned as 'suggestive for benign' on thyroid US, three PTCs and 82 benign nodules were identified, including six cases of nodular hyperplasia and one follicular adenoma that were confirmed with surgery (Figure 6) on page 15 (Figure 7). on page 16For 19 nodules assigned as 'suspicious for benign' on thyroid US, three PTCs and 16 benign lesions were identified. Pathological diagnoses in 'indeterminate' US category included three PTCs, one follicular thyroid carcinoma (FTC), five follicular adenomas, two Hurthle cell adenomas, and five cases of nodular hyperplasia. However, for seven thyroid nodules assigned as 'indeterminate' on thyroid US, patients did not undergo thyroid surgery due to a benign cytology result following US-FNAB. Images for this section: Page 12 of 20

13 Fig. 1: Sonographic Findings in 195 Thyroid Nodules Fig. 2: Comparison of Sonographic and Histologic Findings Page 13 of 20

14 Fig. 3: Graph shows the ROC curve of US diagnostic performance for differentiation of malignant and benign thyroid nodules. The Az value for this ROC curve is Page 14 of 20

15 Fig. 4: Diagnostic Index for Individual Sonographic Feature of Malignant and Benign Thyroid Nodules Fig. 5: A benign nodule assigned as 'suggestive for malignancy' on thyroid US in a 52year-old woman (a case of false positive). Longitudinal US image of the thyroid nodule in the left mid-lobe shows marked hypoechogenicity, an irregular margin and a taller-thanwide shape; however, the lesion was clinically confirmed as a spontaneously collapsed nodule because the patient was a known to have a cystic thyroid nodule in the same site, as detected on a thyroid US examination in a local clinic one year prior. Page 15 of 20

16 Fig. 6: A papillary thyroid carcinoma assigned as 'suggestive for benign' on thyroid US in an 18-year-old woman (a case of false negative). Longitudinal US image of the right thyroid nodule shows an ovoid shape, isoechogenicity, a smooth margin, and peripheral vascularity. Page 16 of 20

17 Fig. 7: A papillary thyroid carcinoma assigned as 'suggestive for benign' on thyroid US in an 18-year-old woman (a case of false negative). Longitudinal US image of the right thyroid nodule shows an ovoid shape, isoechogenicity, a smooth margin, and peripheral vascularity. Page 17 of 20

18 Conclusion In summary, the diagnostic efficacy of thyroid US for nodular thyroid disease was excellent when the present US classification was applied. References 1. Kim E-K, Park CS, Chung WY, et al. New Sonographic Criteria for Recommending Fine-Needle Aspiration Biopsy of Nonpalpable Solid Nodules of the Thyroid. Am J Roentgenol 2002;178(3): Khoo MLC, Asa SL, Witterick IJ, et al. Thyroid calcification and its association with thyroid carcinoma. Head & Neck 2002;24(7): Papini E, Guglielmi R, Bianchini A, et al. Risk of Malignancy in Nonpalpable Thyroid Nodules: Predictive Value of Ultrasound and Color-Doppler Features. J Clin Endocrinol Metab 2002;87(5): Iannuccilli JD, Cronan JJ, Monchik JM. Risk for Malignancy of Thyroid Nodules as Assessed by Sonographic Criteria: The Need for Biopsy. J Ultrasound Med 2004;23(11): Frates MC, Benson CB, Doubilet PM, et al. Can Color Doppler Sonography Aid in the Prediction of Malignancy of Thyroid Nodules? J Ultrasound Med 2003;22(2): Shimura H, Haraguchi K, Hiejima Y, et al. Distinct Diagnostic Criteria for Ultrasonographic Examination of Papillary Thyroid Carcinoma: A Multicenter Study. Thyroid 2005;15(3): Moon W-J, Jung SL, Lee JH, et al. Benign and Malignant Thyroid Nodules: US Differentiation-Multicenter Retrospective Study1. Radiology 2008;247(3): Tae HJ, Lim DJ, Baek KH, et al. Diagnostic Value of Ultrasonography to Distinguish Between Benign and Malignant Lesions in the Management of Thyroid Nodules. Thyroid 2007;17(5): Katz JF, Kane RA, Reyes J, et al. Thyroid nodules: sonographic-pathologic correlation. Radiology 1984;151(3):741. Page 18 of 20

19 10. Brander A, Viikinkoski P, Nickels J, et al. Thyroid gland: US screening in a random adult population. Radiology 1991;181(3): Wienke JR, Chong WK, Fielding JR, et al. Sonographic Features of Benign Thyroid Nodules: Interobserver Reliability and Overlap With Malignancy. J Ultrasound Med 2003;22(10): Brkljacic B, Cuk V, Tomic-Brzac H, et al. Ultrasonic evaluation of benign and malignant nodules in echographically multinodular thyroids. Journal of Clinical Ultrasound 1994;22(2): Frates MC, Benson CB, Charboneau JW, et al. Management of Thyroid Nodules Detected at US: Society of Radiologists in Ultrasound Consensus Conference Statement1. Radiology 2005;237(3): Fukunari N, Nagahama M, Sugino K, et al. Clinical evaluation of color Doppler imaging for the differential diagnosis of thyroid follicular lesions. World J Surg 2004;28(12): Jeh SK, Jung SL, Kim BS, et al. Evaluating the degree of conformity of papillary carcinoma and follicular carcinoma to the reported ultrasonographic findings of malignant thyroid tumor. Korean J Radiol 2007;8(3): Ahuja AT, Chow L, Chick W, et al. Metastatic cervical nodes in papillary carcinoma of the thyroid: Ultrasound and histological correlation. Clinical radiology 1995;50(4): Kessler A, Rappaport Y, Blank A, et al. Cystic appearance of cervical lymph nodes is characteristic of metastatic papillary thyroid carcinoma. Journal of Clinical Ultrasound 2003;31(1): Ying M, Ahuja A, Metreweli C. Diagnostic accuracy of sonographic criteria for evaluation of cervical lymphadenopathy. J Ultrasound Med 1998;17(7): Kakkos SK, Scopa CD, Chalmoukis AK, et al. Relative risk of cancer in sonographically detected thyroid nodules with calcifications. Journal of Clinical Ultrasound 2000;28(7): Kwak MS, Baek JH, Kim YS, et al. Patterns and Significance of Peripheral Calcifications of Thyroid Tumors seen on Ultrasound. J Korean Radiol Soc 2005;53(6): Wang N, Xu Y, Ge C, et al. Association of sonographically detected calcification with thyroid carcinoma. Head & Neck 2006;28(12): Kim BM, Kim MJ, Kim E-K, et al. Sonographic Differentiation of Thyroid Nodules With Eggshell Calcifications. J Ultrasound Med 2008;27(10):1425. Page 19 of 20

20 23. Park M, Shin JH, Han B-K, et al. Sonography of thyroid nodules with peripheral calcifications. Journal of Clinical Ultrasound 2009;37(6): Kim DW, Lee EJ, Kim SH, et al. Ultrasound-Guided Fine-Needle Aspiration Biopsy of Thyroid Nodules: Comparison in Efficacy According to Nodule Size. Thyroid 2009;19(1):27. Personal Information Y.H. Lee MD. Department of Radiology, Inje University Pusan Paik hospital, Busan, Korea. Page 20 of 20