Role of sonoelastography in the evaluation of superficial soft tissue lesions: qualitative and quantitative study

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1 Role of sonoelastography in the evaluation of superficial soft tissue lesions: qualitative and quantitative study Poster No.: C-2016 Congress: ECR 2013 Type: Scientific Exhibit Authors: N. Magarelli, C. Carducci, C. Bucalo, L. Filograna, S Rapisarda, C. Dell'atti, A. Leone, L. Bonomo ; Rome/IT, 2 3 Palermo/IT, Roma/IT Keywords: Cancer, Diagnostic procedure, Ultrasound, Musculoskeletal soft tissue DOI: /ecr2013/C-2016 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 16

2 Purpose Sonoelastography (SE) is a new ultrasound technique currently used for the evaluation and characterization of soft tissue lesions. Generally, the literature reports a superior stiffness of malignant lesions with respect to benign alterations of breast, liver, thyroid, prostate, parotid and lymph nodes. Few studies focused on SE features of musculoskeletal lesions. The majority of previous studies for differentiating benign from malignant lesions adopted qualitative scales for evaluation of tissue stiffness. The aim of this study is discuss the SE features of superficial soft tissue lesions and to evaluate the clinical feasibility of a qualitative and quantitative study of benign and malignant superficial soft tissue lesions using SE. Methods and Materials Prospective study Institutional review board approval and informed consent study were obtained Population study: 28 patients with superficial soft tissue lesions Examination: - gray-scale ultrasonography (US) - color and/or power doppler - sonoelastography in compression and decompression phase (My Lab 70 XVG system-esaote-multifrequency trasducer 5-12 MHz) The strain data are represented as color-scale image and superimposed onto the relative B-mode image. Conventionally, hard areas are represented in blue, soft areas in red, and firm areas with an intermediate consistency/stiffness in green. Page 2 of 16

3 This study consisted of two parts: qualitative and quantitative. Qualitative analysis: - all examinations were performed by a radiologist, blinded to clinical examination findings (15 years of experience in muscolo-skeletal radiology and ultrasound) - all images were revalued by two radiologists, blinded to clinical examination and SE results. (Fig.1) Quantitative analysis (post-processing): - data analysis: Image J software (1.45 version) - each pixel was separeted into red, green and blue to obtain an histogram - median and fraction area for each color (red, green, blue) within a region of interest (ROI) adapted to the lesion - differences between fraction area and differences between median values in compression and decompression phase Reference standard: histological findings Statistical analysis: sensitivity, specificity, negative and positive predictive value, diagnostic accuracy Images for this section: Page 3 of 16

4 Fig. 1: Fleury E, et al. Apparence of breast masses on sonoelastography with special focus on the diagnosis of fibroadenomas. Eur. Radiol. 2009; 19: MODIFIED Page 4 of 16

5 Fig. 2: SE scan before post-processing and monochromatic images (red, green and blue) after post-processing. ROI in the anterior compartment of thigh: normal appearance Page 5 of 16

6 Fig. 3: Gray-scale US and Color-Doppler US of a benign and a malignant lesion Page 6 of 16

7 Results Patient population In our study population 14/28 lesions were malignant and 14/28 lesions (50%) were benign. In the qualitative analysis: Malignant lesions: (Fig. 4,5,6,7) 14/14: score 4-5 Benign lesions: (Fig.8,9,10) 10/14: score 1-2 4/14: score 3 In the quantitative analysis (post-processing): differences between median values in compression and decompression phase and differences between fraction area were different in blue,red and green color: Blue statistically significant correlation with malignant lesions (respectively p<0.007; p<0.002) Red statistically significant correlation with benign lesions (respectively p<0.01; p<0.002) Green no statistically significant correlation with benign and malignant lesions (respectively p<0.30; p<0.75) Statistical Analysis Specificity: 77% Page 7 of 16

8 Sensitivity: 100% Diagnostic accuracy: 86% Positive predictive value: 71% Negative predictive value: 100% Images for this section: Fig. 4: Fig. 4 Malignant lesion (anaplastic sarcoma): image in compression phase. Qualitative analysis. Page 8 of 16

9 Fig. 5: Malignant lesion (anaplastic sarcoma): image in decompression phase. Score 4: there is a significatively increase of dark color (blue) in decompression. Qualitative analysis. Page 9 of 16

10 Fig. 6: Malignant lesion (mixoid fibrosarcoma): image in compression phase. Qualitative analysis. Page 10 of 16

11 Fig. 7: Malignant lesion (mixoid fibrosarcoma): image in decompression phase. Score 5: there is no difference between two phases (blue). Qualitative analysis. Page 11 of 16

12 Fig. 8: Benign lesion (schwannoma): image in compression phase. Qualitative analysis. Page 12 of 16

13 Fig. 9: Benign lesion (schwannoma): image in decompression phase. Score 3: there is a mild increase of light color in decompression. Qualitative analysis. Page 13 of 16

14 Fig. 10: Benign lesion: lipoma. Image in decompression phase. Page 14 of 16

15 Conclusion Preliminary results showed a good correlation between SE and reference standard. SE demonstrated all malignant lesions as hard lesions (increased stiffness), confirmed by increasing of dark color in the qualitative analysis and increasing of values of blue in terms of median and fraction area in the selected ROI. The differentiation of benign tissue from malignant tumour is sometimes difficult with conventional US techniques, color and/or power-doppler add information about vascular pattern of the lesions and SE provides additional information about tissue stiffness. Limits of SE: presence of artifacts (blue color in subcutaneous fat tissue in very superficial lesions and black color, probably due to interface between soft and calcified tissue - different acoustic impedance- in the context of lesions with calcified and/or ossified matrix) and difficult to obtain an uniform and unidirectional strength on lesions located in particular regions. In conclusion, SE could be considered a useful tool for differentiating between benign and malignant superficial soft tissue lesions. Clinical relevance SE in the study of superficial soft tissue lesions could have a clinical application in term of reduction of biopsies of superficial soft tissue lesions as reported in literature for breast masses, thyroid nodules, testicular and prostate cancer and may add a value in the characterization of superficial soft tissue lesions. References Ophir J, Cespedes I, Ponnekanti H, et al. Elastography: a quantitative method for immaging the elasticity of biological tissues. Ultrason Immaging. 1991; 13: Ophir J, Alam SK, Garra B, et al. Elastography: ultrasonic estimation and immaging of elastic proprieties of tissue. J. Eng. Med. 1999; 213 (H13): Ophir J, Kallel F, Varghese T, et al. Elastography: a system approach. Int. J. Imaging Syst. 1997; 8: Page 15 of 16

16 4. Wojcinski S, Farrokh A, Weber S et al (2010) Multicenter study of ultrasound real-time tissue elastography in 779 cases for the assessment of breast lesions: improved diagnostic performance by combining the BI-RADS(R)-US classification system with sonoelastography. Ultraschall Med 31: Adamietz BR, Meier-Meitinger M, Fasching P et al (2011) New diagnostic criteria in real-time elastography for the assessment of breast lesions. Ultraschall Med 32: Bojunga J, Herrmann E, Meyer G, Weber S, Zeuzem S, Friedrich- Rust M (2010) Real-time elastography for the differentiation of benign and malignant thyroid nodules: a meta-analysis. Thyroid 20: Wu CH, Chang KV, Mio S, Chen WS, Wang TG. Sonoelastography of the plantar fscia. Radiology 2011May; 259: Holtel MR (2010) Emerging technology in head and neck ultrasonography. Otolaryngol Clin North Am 43: , vii 9. Luo S, Kim EH, Dighe M, Kim Y (2011) Thyroid nodule classification using ultrasound elastography via linear discriminant analysis. Ultrasonics 51: Oliver C, Vaillant-Lombard J, Albarel F et al (2011) What is the contribution of elastography to thyroid nodules evaluation? Ann Endocrinol (Paris) 72: Lyshchik A, Higashi T, Asato R et al (2007) Cervical lymph node metastases: diagnosis at sonoelastography-initial experience. Radiology 243: Dumitriu D, Dudea SM, Botar-Jid C, Baciut G (2010) Ultrasonographic and sonoelastographic features of pleomorphic adenomas of the salivary glands. Med Ultrason 12: Personal Information Chiara Carducci MD Catholic University of Sacred Heart University Hospital "A.Gemelli", Roma,Italy chi.carducci@gmail.com Page 16 of 16