J Breast Cancer.  2018 Jun;21(2):190-196. 10.4048/jbc.2018.21.2.190.

Ex Vivo Shear-Wave Elastography of Axillary Lymph Nodes to Predict Nodal Metastasis in Patients with Primary Breast Cancer

• Bae SJ
• Park JT
• Park AY
• Youk JH
• Lim JW
• Lee HW
• Lee HM
• Ahn SG
• Son EJ
• Jeong J

• KMID: 2413938
• DOI: http://doi.org/10.4048/jbc.2018.21.2.190

Abstract

PURPOSE
There is still a clinical need to easily evaluate the metastatic status of lymph nodes during breast cancer surgery. We hypothesized that ex vivo shear-wave elastography (SWE) would predict precisely the presence of metastasis in the excised lymph nodes.
METHODS
A total of 63 patients who underwent breast cancer surgery were prospectively enrolled in this study from May 2014 to April 2015. The excised axillary lymph nodes were examined using ex vivo SWE. Metastatic status was confirmed based on the final histopathological diagnosis of the permanent section. Lymph node characteristics and elasticity values measured by ex vivo SWE were assessed for possible association with nodal metastasis.
RESULTS
A total of 274 lymph nodes, harvested from 63 patients, were examined using ex vivo SWE. The data obtained from 228 of these nodes from 55 patients were included in the analysis. Results showed that 187 lymph nodes (82.0%) were nonmetastatic and 41 lymph nodes (18.0%) were metastatic. There was significant difference between metastatic and nonmetastatic nodes with respect to the mean (45.4 kPa and 17.7 kPa, p<0.001) and maximum (55.3 kPa and 23.2 kPa, p<0.001) stiffness. The elasticity ratio was higher in the metastatic nodes (4.36 and 1.57, p<0.001). Metastatic nodes were significantly larger than nonmetastatic nodes (mean size, 10.5 mm and 7.5 mm, p<0.001). The size of metastatic nodes and nodal stiffness were correlated (correlation coefficient of mean stiffness, r=0.553). The area under curve of mean stiffness, maximum stiffness, and elasticity ratio were 0.794, 0.802, and 0.831, respectively.
CONCLUSION
Ex vivo SWE may be a feasible method to predict axillary lymph node metastasis intraoperatively in patients undergoing breast cancer surgery.

Keyword

Axilla; Breast neoplasms; Elasticity imaging techniques; Lymphatic metastasis

MeSH Terms

Area Under Curve
Axilla
Breast Neoplasms*
Breast*
Diagnosis
Elasticity
Elasticity Imaging Techniques*
Humans
Lymph Nodes*
Lymphatic Metastasis
Methods
Neoplasm Metastasis*
Prospective Studies

Figure

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  Figure 1 Characteristics of metastatic and nonmetastatic lymph node. Box plot showing size (A), mean stiffness (B), max stiffness (C), and the elasticity ratio (D) between nonmetastatic and metastatic lymph nodes.

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  Figure 2 Correlation coefficients for metastatic node size and ex vivo shear-wave elastic values. (A) Mean stiffness, (B) max stiffness.

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  Figure 3 Receiver operating characteristic (ROC) curve analysis of size, mean stiffness, max stiffness, and elasticity ratio. (A) Lymph nodes with micro-metastasis were regarded as nonmetastatic nodes, (B) lymph nodes with micro-metastasis were regarded as metastatic nodes.

Reference

1. Kilic F, Velidedeoglu M, Ozturk T, Kandemirli SG, Dikici AS, Er ME, et al. Ex vivo assessment of sentinel lymph nodes in breast cancer using shear wave elastography. J Ultrasound Med. 2016; 35:271–277. PMID: 26715659.

2. Garra BS. Elastography: current status, future prospects, and making it work for you. Ultrasound Q. 2011; 27:177–186. PMID: 21873855.

3. Faruk T, Islam MK, Arefin S, Haq MZ. The journey of elastography: background, current status, and future possibilities in breast cancer diagnosis. Clin Breast Cancer. 2015; 15:313–324. PMID: 25858446.

4. Jeong WK, Lim HK, Lee HK, Jo JM, Kim Y. Principles and clinical application of ultrasound elastography for diffuse liver disease. Ultrasonography. 2014; 33:149–160. PMID: 25038804.

5. Anvari A, Barr RG, Dhyani M, Samir AE. Clinical application of sonoelastography in thyroid, prostate, kidney, pancreas, and deep venous thrombosis. Abdom Imaging. 2015; 40:709–722. PMID: 25750099.

6. Youk JH, Son EJ, Park AY, Kim JA. Shear-wave elastography for breast masses: local shear wave speed (m/sec) versus Young modulus (kPa). Ultrasonography. 2014; 33:34–39. PMID: 24936493.

7. Youk JH, Gweon HM, Son EJ, Han KH, Kim JA. Diagnostic value of commercially available shear-wave elastography for breast cancers: integration into BI-RADS classification with subcategories of category 4. Eur Radiol. 2013; 23:2695–2704. PMID: 23652850.

8. Barr RG, Zhang Z. Shear-wave elastography of the breast: value of a quality measure and comparison with strain elastography. Radiology. 2015; 275:45–53. PMID: 25426770.

9. Lee SH, Chang JM, Cho N, Koo HR, Yi A, Kim SJ, et al. Practice guideline for the performance of breast ultrasound elastography. Ultrasonography. 2014; 33:3–10. PMID: 24936489.

10. Evans A, Whelehan P, Thomson K, McLean D, Brauer K, Purdie C, et al. Quantitative shear wave ultrasound elastography: initial experience in solid breast masses. Breast Cancer Res. 2010; 12:R104. PMID: 21122101.

11. Tourasse C, Dénier JF, Awada A, Gratadour AC, Nessah-Bousquet K, Gay J. Elastography in the assessment of sentinel lymph nodes prior to dissection. Eur J Radiol. 2012; 81:3154–3159. PMID: 22656671.

12. Taylor K, O'Keeffe S, Britton PD, Wallis MG, Treece GM, Housden J, et al. Ultrasound elastography as an adjuvant to conventional ultrasound in the preoperative assessment of axillary lymph nodes in suspected breast cancer: a pilot study. Clin Radiol. 2011; 66:1064–1071. PMID: 21835398.

13. Evans A, Rauchhaus P, Whelehan P, Thomson K, Purdie CA, Jordan LB, et al. Does shear wave ultrasound independently predict axillary lymph node metastasis in women with invasive breast cancer. Breast Cancer Res Treat. 2014; 143:153–157. PMID: 24305976.

14. Choi JJ, Kang BJ, Kim SH, Lee JH, Jeong SH, Yim HW, et al. Role of sonographic elastography in the differential diagnosis of axillary lymph nodes in breast cancer. J Ultrasound Med. 2011; 30:429–436. PMID: 21460142.

15. Skerl K, Vinnicombe S, Giannotti E, Thomson K, Evans A. Influence of region of interest size and ultrasound lesion size on the performance of 2D shear wave elastography (SWE) in solid breast masses. Clin Radiol. 2015; 70:1421–1427. PMID: 26455652.

16. Dabbs DJ, Fung M, Landsittel D, McManus K, Johnson R. Sentinel lymph node micrometastasis as a predictor of axillary tumor burden. Breast J. 2004; 10:101–105. PMID: 15009035.

17. Ophir J, Céspedes I, Ponnekanti H, Yazdi Y, Li X. Elastography: a quantitative method for imaging the elasticity of biological tissues. Ultrason Imaging. 1991; 13:111–134. PMID: 1858217.

18. Shiina T, Nightingale KR, Palmeri ML, Hall TJ, Bamber JC, Barr RG, et al. WFUMB guidelines and recommendations for clinical use of ultrasound elastography: Part 1: basic principles and terminology. Ultrasound Med Biol. 2015; 41:1126–1147. PMID: 25805059.

19. Goddi A, Bonardi M, Alessi S. Breast elastography: a literature review. J Ultrasound. 2012; 15:192–198. PMID: 23449849.

20. Cho N, Moon WK, Park JS, Cha JH, Jang M, Seong MH. Nonpalpable breast masses: evaluation by US elastography. Korean J Radiol. 2008; 9:111–118. PMID: 18385557.

21. Au FW, Ghai S, Moshonov H, Kahn H, Brennan C, Dua H, et al. Diagnostic performance of quantitative shear wave elastography in the evaluation of solid breast masses: determination of the most discriminatory parameter. AJR Am J Roentgenol. 2014; 203:W328–W336. PMID: 25148191.

22. Lee BE, Chung J, Cha ES, Lee JE, Kim JH. Role of shear-wave elastography (SWE) in complex cystic and solid breast lesions in comparison with conventional ultrasound. Eur J Radiol. 2015; 84:1236–1241. PMID: 25937525.

23. Berg WA, Cosgrove DO, Doré CJ, Schäfer FK, Svensson WE, Hooley RJ, et al. Shear-wave elastography improves the specificity of breast US: the BE1 multinational study of 939 masses. Radiology. 2012; 262:435–449. PMID: 22282182.

24. Cosgrove DO, Berg WA, Doré CJ, Skyba DM, Henry JP, Gay J, et al. Shear wave elastography for breast masses is highly reproducible. Eur Radiol. 2012; 22:1023–1032. PMID: 22210408.