Indian Journal of Radiology Indian Journal of Radiology  

   Login   | Users online: 2778

Home Bookmark this page Print this page Email this page Small font sizeDefault font size Increase font size     

 

 Table of Contents    
WOMENS RADIOLOGY  
Year : 2011  |  Volume : 21  |  Issue : 4  |  Page : 301-305
Differential diagnosis of breast lesions using ultrasound elastography


Department of Radiology and Imaging, University of Medicine and Pharmacy Craiova, Romania

Click here for correspondence address and email

Date of Web Publication8-Dec-2011
 

   Abstract 

Context: The recent introduction of elastography has increased the specificity of USG and enabled early diagnosis of breast cancer. Quantitative elastography, especially with strain ratio (SR) index, improves diagnostic accuracy and decreased number of biopsies. Aims: The purpose of this study was to assess the role of USG elastography in the differential diagnosis of breast lesions. Settings and Design: This prospective study was conducted in the University of Medicine and Pharmacy Research Centre of Craiova. Materials and Methods: Fifty-eight patients diagnosed with breast lesions between January 2009 and January 2010 were included in this prospective study. All the patients were examined in the supine position, and the B-mode USG image was displayed alongside the elastography strain image. For obtaining the elastography images we used a EUS Hitachi EUB 8500 ultrasound system with a 6.5-MHz linear probe. The elastography strain images were scored according to the Tsukuba elasticity score. Statistical Analysis: We performed receiver operator characteristic (ROC) analysis for assessment of the role of USG elastography in the diagnosis of breast lesions. Results: We obtained a sensitivity of 86.7% and a specificity of 92.9% for elasticity score and a sensitivity of 93.3% and a specificity of 92.9% for SR (when a cutoff point of 3.67 was used). There was very good correlation between SR and elasticity score (Spearman coefficient of 0.911). Conclusions: Elastography is a fast, simple method that can complement conventional USG examination. This method has the lowest cost/efficiency ratio and it is also the most noninvasive and accessible imaging method, with an accuracy comparable to MRI.

Keywords: Breast lesions; receiver operator characteristic analysis; ultrasound elastography

How to cite this article:
Gheonea IA, Stoica Z, Bondari S. Differential diagnosis of breast lesions using ultrasound elastography. Indian J Radiol Imaging 2011;21:301-5

How to cite this URL:
Gheonea IA, Stoica Z, Bondari S. Differential diagnosis of breast lesions using ultrasound elastography. Indian J Radiol Imaging [serial online] 2011 [cited 2019 Sep 20];21:301-5. Available from: http://www.ijri.org/text.asp?2011/21/4/301/90697

   Introduction Top


The high incidence of breast cancer and its slow evolution before diagnosis have led to research on new diagnostic techniques. [1],[2],[3] The recent introduction of elastography has increased the specificity of USG and enabled earlier diagnosis of breast cancer. The use of quantitative elastography with strain ratio (SR) improves diagnostic accuracy in cases with equivocal Stavros criteria (stages 3 and 4 BI-RADS).

USG elastography (SE) differentiates between benign and malignant lesions on the basis of their elasticity: benign lesions have an elasticity similar to the surrounding tissue, while malignant lesions are harder than adjacent tissue. [4]

The purpose of this study was to assess the role of SE in the diagnosis of breast lesions. Malignant tumors have reduced elasticity and also display larger dimensions on elastography due to the accompanying desmoplastic reaction. [5],[6] Benign lesions appear similar to the adjacent tissues and have a smaller diameter than on B-mode USG images. [7],[8]


   Materials and Methods Top


In this prospective study, consecutive patients presenting with palpable breast lesions were assessed with conventional B-mode USG. Those confirmed to have a breast lesion were then assessed with SE after informed consent was obtained. SE was performed by a single experienced physician who was not aware of the results of previous investigations. The operator was not blinded at conventional USG because the lesion was localized first with conventional B-mode USG and then SE was done. The patients were examined in the supine position with the arm placed behind the head. The USG probe, lubricated with gel, was placed on the breast and a radial, ductal exploration was made as follows: the transducer was placed perpendicularly to the skin and radially on the breast, with one end overlapping on the areola and the other end directed toward the periphery. The orientation of the transducer was such that the nipple appeared at the left-hand side of the image. The transducer was then rotated around the areola. When a duct was identified, the rotation of the transducer was halted and it was moved back and forth laterally for thorough evaluation of the duct and its branches and the lobules. The transducer was then rotated again until the next ducto-lobular complex was found. This procedure was repeated until all the ductal structures were evaluated. A second rotating sweep was performed over the upper outer peripheral part of each breast. The B-mode US image was displayed alongside the elastography strain image to ensure that the assessment was made in the area of interest. We included in the area of interest the lesion and also the subcutaneous layers and the pectoralis muscle, without the costal cartilages.

A EUS Hitachi EUB 8500 US system (Hitachi Medical, Tokyo, Japan) with an elastography module and a 6.5 MHz linear probe was used to obtain the B-mode and elastography strain images. The images were acquired in a ductal, radial manner as described above and the elastography strain images were scored according to the Tsukuba elasticity score developed by Itoh and Ueno. [4] Ductal USG combined with SE is defined as full-breast elastography, a new concept initiated by Amy D [9] We used five scores for characterizing the lesions: score 1 for lesions with elasticity similar to the surrounding breast tissue, displayed in green color on elastography; score 2 for lesions with inhomogeneous elasticity, with green and blue elastography appearance; score 3 for lesions with an elastic green periphery and a stiff blue centre; score 4 for nodules that were entirely stiff, showing no deformation; score 5 for cases where the whole lesion and the adjacent tissue showed a blue appearance on the elasticity image.

For all lesions we calculated the strain ratio (SR). The average strain of the lesion was determined by selecting a region of interest (ROI) from the lesion and a corresponding ROI of the adjacent adipose tissue. Using specific software, the SR value was displayed on a static image as the ratio of tumor-adjusted ROI and the ROI placed in the adjacent fatty tissue. We used fine needle aspiration cytology (FNAC) (n=12) or excision biopsy (n=18) for histopathological analysis of the malignant lesions. The benign lesions were diagnosed by a combination of FNAC (n=10), excision biopsy (n=7), and follow-up for 6 months (n=11).


   Results Top


In this study we included 58 patients with breast lesions confirmed on US. The average age of the women was 45.3 years. There were 28 (48.27%) benign and 30 (51.73%) malignant lesions. Among the benign nodules the common lesions were fibroadenoma, cyst, and fibrocystic change. Among the malignant nodules, the most common lesion was infiltrative ductal carcinoma. Ductal carcinoma in situ was diagnosed in 10 cases [Table 1].
Table 1: Final pathology diagnosis of all lesions


Click here to view


Fibroadenomas appeared either softer than or had the same elasticity as adjacent glandular tissue [Figure 1] and [Figure 2]. Breast cysts had an elasticity score of 1 with a characteristic three-layered appearance: blue-green-red (BGR), blue being the superficial color and red the deep one, even in large dimension lesions [Figure 3]. Fibrocystic nodules had elasticity similar to surrounding parenchyma [Figure 4]. The mean elasticity score for benign lesions was 1.92±1.01. Breast carcinomas showed an average elasticity score of 4.23±0.89; they appeared larger on the elastography image because of better visualization of the surrounding desmoplastic reaction [Figure 5] and [Figure 6];[Table 2].
Table 2: The elasticity score for benign and malignant lesions


Click here to view
Figure 1: (A, B) SE image (A) and B-mode USG image (B) show a hypoechoic circumscribed lesion that is predominantly elastic, displaying a mosaic pattern of green and blue. This was a fibroadenoma with a Tsukuba elasticity score of 2 and an SR of 1.76

Click here to view
Figure 2: (A, B) SE image (A) and B-mode USG image (B) reveal a fibroadenoma-like lesion that is predominantly green, with an SR of 1.05; this is typical of a benign lesion

Click here to view
Figure 3: (A, B) SE image (A) and B-mode USG image (B) show the typical elastographic appearance (blue, green, red) of a cyst. This was a cyst of 26.4 mm diameter in a 23-year-old patient

Click here to view
Figure 4: (A, B) SE image (A) and B-mode USG image (B) reveal an image of fibrocystic dysplasia with a Tsukuba elasticity score of 1 and an SR of 1.46, suggestive of a benign lesion

Click here to view
Figure 5: (A, B) SE image (A) and B-mode USG image (B) -- the lesion (arrows) and the surrounding tissue (arrowhead) were colored blue, with an elasticity score of 5. Pathology revealed an invasive ductal carcinoma

Click here to view
Figure 6: (A, B) SE image (A) and B-mode USG image (B) reveal a small, suspicious, stiff lesion (arrows). The lesion appears to be larger on the elastographic image due to the accompanying desmoplastic reaction with a Tsukuba elasticity score of 5 and an SR of 3.98. Pathology revealed ductal invasive carcinoma

Click here to view


After FNAC and excision biopsy, four lesions (14.28%) with elasticity score 3, one lesion (3.57%) with elasticity score 4 [Figure 7], and one lesion (3.57%) with elasticity score 5 were found to be benign; also, one lesion (3.33%) with elasticity score 1 and three lesions (10.72%) with elasticity score 3 [Figure 8] turned out to be malignant lesions.
Figure 7: (A,B) SE image (A) and B-mode USG image (B) show a hypoechoic lesion in the right breast, with small foci of calcification (arrows) predominantly blue on elastography, with an elasticity score of 4. It was a calcified fibroadenoma

Click here to view
Figure 8: (A,B) SE image (A) and B-mode USG image (B) performed in a patient with fibrocystic dysplasia reveals a hypoechoic lesion with irregular boundaries (arrows). Tsukuba elasticity score was 3. Pathology showed in situ ductal carcinoma

Click here to view


The average SR for benign lesions was 2.08, which was significantly lower than that for malignant lesions (mean SR: 6.28). To calculate the sensitivity and specificity of elastography, lesions with elasticity scores 1-3 were classified as benign, while those with scores of 4 or 5 were classified as malignant. For assessment of the role of SE in the differential diagnosis of breast lesions, we performed a receiver operator characteristic (ROC) analysis. We obtained a sensitivity of 86.7% and a specificity of 92.9% [Figure 9]A for elasticity score (area under the ROC curve=0.928; 95% CI=0.829 to 0.979; P=0.0001) and a sensitivity of 93.3% and a specificity of 92.9% for SR, when a cutoff point of 3.67 was used (area under the ROC curve=0.965, 95% CI=0.880 to 0.995; P=0.0001) [Figure 9]B. Furthermore, the Spearman coefficient of rank correlation for SR values and elasticity score was 0.911 (95% CI 0.853 to 0.946; P<0.0001), showing that there was very good agreement between the two methods.
Figure 9: Sensitivity and specificity values on ROC analysis for elasticity score (A) and for SR (B) (MedCalc® software v. 9, 2008, Mariakerke, Belgium)

Click here to view



   Discussion Top


The interpretation of breast nodules detected on B-mode US relies mainly on morphological criteria. To improve the accuracy of USG, additional techniques can be used, including Doppler and harmonic imaging. [10],[11] Over the last decade, there has been increasing interest in imaging the elasticity of biological tissues to complement information from standard anatomical imaging. SE can differentiate between benign and malignant lesions on the basis of their firmness. The lesion's contours, dimensions, color, SR, and appearance on elastography are some of the criteria used for differentiating benign from malignant lesions. The SR represents the relative compliance stiffness of lesions compared with surrounding tissues. Malignant lesions, which are very stiff, deform less and are displayed in blue on the elastography images, whereas benign lesions deform much more easily and are depicted in green color. [12],[13]

Results of the clinical use of SE were initially published in 1997-2001, [13] but it was only in 2003-2004 that US equipment was developed that had incorporated software for real-time processing of elastography images and routine US examinations. [14] For characterization of breast lesions, two elasticity scoring systems have been proposed: the Tsukuba score developed by Itoh and Ueno [4] and another designed by the Italian Research Group after Locatelli, Rizzatto et al. [10]

In this study, when a cutoff point of 3 was used, we found a sensitivity of 86.7% and a specificity of 92.9%, results that are consistent with other published data on the use of real-time US elastography. [4],[15] A sensitivity of 77.6% and 79.6% and specificity of 91.5% and 84.5% were reported by Thomas et al., in a study where 108 breast lesions were examined by two examiners separately. [15] Another study of 111 lesions reported higher values: sensitivity of 89.3% and 83.3% and specificity of 93.1% and 86.7%. [4]

As the SR ratio of >3 is generally considered suspicious for malignancy, [16] there is ongoing research for establishing the correct values for better differentiation of benign and malignant lesions. In our study, the mean SR for benign lesions was 2.08 and for malignant lesions it was 6.28, with the cutoff point being 3.67. In comparison, the critical SR value for diagnosing breast cancer was 3.08 in a study by Zhi et al. [17]

Routine USG examination detects many nonpalpable lesions and it is not very specific for screening cases. [18] The advantages of ductal USG is that standardized anatomic examination of the breast is possible, with precise localization of lesions and the visualization of connections with epithelial/parenchymatous breast structures, generally in the area of specific ducto-lobular units described by histologists. Ductal USG is an anatomical method of breast investigation that allows the correct assessment of the internal structures of the breast. The recent introduction of SE, especially quantitative elastography with SR, has increased the specificity of USG and enabled early diagnoses of subcentimeter breast cancer and decreased the need for biopsies. [19]

In the clinical setting SE is useful for deciding whether to follow-up patients with imaging or to intervene. [19] Sometimes it is difficult to differentiate between scores 2 and 3 on SE images, but it is very easy to diagnose a lesion as having score 1, because no blue area is observed. [20] Our study showed that there was good correlation (Spearman coefficient=0.911) between qualitative and quantitative elastography methods (elasticity score and SR) and we suggest that by performing both techniques a more confident diagnosis can be made. SE is less sensitive than standard USG when dealing with nonfocal anomalies and is not indicated for the evaluation of postoperative changes, diffuse lesions, or large ones that exceed the probe length or its field of view (FOV). [21] SE is also of limited usefulness in very dense fibrous parenchyma and in the case of hematomas or breast implants. [11] Some studies have also demonstrated the value of elastography in the benign-malignant differentiation of lymph nodes. [22]

The introduction and validation of the concept of full-breast USG have increased the sensitivity of SE. [9] Full-breast USG allows the systematic diagnosis of lesions using the ductal technique; it is not operator dependent, has high specificity, and allows the precise localization of lesions within the breast gland (galactophore ducts, lobules, and ducto-lobular terminal units). [9] Also the use of Doppler and elastography techniques permits evaluation of the risk of neoplastic transformation, with a specificity of over 90%. [4],[11]

In conclusion, breast SE is a very simple and rapid method that can improve the sensitivity and specificity of USG, especially when dealing with BI-RADS 3 or 4 lesions. Ductal USG combined with SE is a rapid technique, with the lowest cost/efficiency ratio of all the modalities; it is the most noninvasive and accessible imaging method, with accuracy comparable with MRI, and can decrease the rate of unnecessary biopsies.

 
   References Top

1.Krouskop TA, Wheeler TM, Kallel F, Garra BS, Hall T. Elastic moduli of breast and prostate tissues under compression. Ultrason Imaging 1998;20:260-74.  Back to cited text no. 1
[PUBMED]    
2.Ophir J, Céspedes I, Ponnekanti H, Yazdi Y, Li X. Elastography: A quantitative method for imaging the elasticity of biological tissues. Ultrason Imaging 1991;13:111-34.  Back to cited text no. 2
    
3.Klauser AS, Faschingbauer R, Jaschke WR. Is sonoelastography of value in assessing tendons? Semin Musculoskelet Radiol 2010;14:323-33.  Back to cited text no. 3
[PUBMED]    
4.Itoh A, Ueno E, Tohno E, Kamma H, Takahashi H, Shiina T, et al. Breast disease: Clinical application of US elastography for diagnosis. Radiology 2006;239:341-50.  Back to cited text no. 4
[PUBMED]  [FULLTEXT]  
5.Burnside ES, Hall TJ, Sommer AM, Hesley GK, Sisney GA, Svensson WE, et al. Differentiating benign from malignant solid breast masses with US strain imaging. Radiology 2007;245:401-10.   Back to cited text no. 5
[PUBMED]  [FULLTEXT]  
6.Regner DM, Hesley GK, Hangiandreou NJ, Morton MJ, Nordland MR, Meixner DD, et al. Breast lesions: Evaluation with US strain imaging-clinical experience of multiple observers. Radiology 2006;238:425-37.   Back to cited text no. 6
[PUBMED]  [FULLTEXT]  
7.Garra BS, Cespedes EI, Ophir J, Spratt SR, Zuurbier RA, Magnant CM, et al. Elastography of breast lesions: Initial clinical results. Radiology 1997;202:79-86.   Back to cited text no. 7
[PUBMED]  [FULLTEXT]  
8.Hall TJ, Zhu Y, Spalding CS. In vivo real-time freehand palpation imaging. Ultrasound Med Biol 2003;29:427-35.  Back to cited text no. 8
[PUBMED]  [FULLTEXT]  
9.Amy D. Echographie mammaire: Echoanatomie. Jl mensuel d`echographie: LUS 2000;10:654-62.  Back to cited text no. 9
    
10.Rizzatto G. Real-time elastography of the breast in clinical practice - The Italian experience. Medix Hitachi Suppl 2007;1 :12-5.  Back to cited text no. 10
    
11.Itoh A. Review of the techniques and diagnostic criteria of breast ultrasound elastography. Medix Hitachi Suppl 2007;1:8-11.  Back to cited text no. 11
    
12.Hong AS, Rosen EL, Soo MS, Baker JA. BIRADS for sonography: Positive and negative values of sonographic features. AJR Am J Roentogenol 2005;184:1260-5.  Back to cited text no. 12
    
13.Ueno E, Shiina T, Kubota M, Sawai K, editors. Research and Development in Breast Ultrasound. In vivo Breast Examination by Real-Time Freehand Elasticity Imaging System, Tokyo: Springer-Verlag; 2005. p. 7-16.  Back to cited text no. 13
    
14.Konofagou EE. Quo Vadis elasticity imaging? Ultrasonics 2004;42:331-6.  Back to cited text no. 14
[PUBMED]  [FULLTEXT]  
15.Thomas A, Fischer T, Frey H, Ohlinger R, Grunwald S, Blohmer JU, et al. Real-time elastography-an advanced method of ultrasound: First results in 108 patients with breast lesions. Ultrasound Obstet Gynecol 2006;28:335-40.  Back to cited text no. 15
[PUBMED]  [FULLTEXT]  
16.Wang Z, Yang T, Wu Z, Tang S, Liang X, Qin A, et al. Correlation between elastography score and strain rate ratio in breast small tumor. Zhong Nan Da Xue Xue Bao Yi Xue Ban 2010;35:928-32.  Back to cited text no. 16
[PUBMED]  [FULLTEXT]  
17.Zhi H, Xiao XY, Yang HY, Wen YL, Ou B, Luo BM, et al. Semi-quantitating stiffness of breast solid lesions in ultrasonic elastography. Acad Radiol 2008;15:1347-53.  Back to cited text no. 17
[PUBMED]  [FULLTEXT]  
18.Stavros AT, Thickman D, Rapp CL, Dennis MA, Parker SH, Sisney GA. Solid breast nodules. Use of sonography to distinguish benign and malignant lesions. Radiology 1995;196:123-34.  Back to cited text no. 18
[PUBMED]  [FULLTEXT]  
19.Thomas A, Kümmel S, Fritzsche F, Warm M, Ebert B, Hamm B, et al. Real-time sonoelastography performed in addition to B-mode ultrasound and mammography: Improved differentiation of breast lesions? Acad Radiol 2006;13:1496-504.  Back to cited text no. 19
    
20.Scaperrotta G, Ferranti C, Costa C, Mariani L, Marchesini M, Suman L, et al. Role of sonoelastography in non-palpable breast lesions. Eur Radiol 2008;18:2381-9.  Back to cited text no. 20
[PUBMED]  [FULLTEXT]  
21.Giuseppetti GM, Martegani A, Di Cioccio B, Baldassarre S. Elastosonography in the diagnosis of the nodular breast lesions: Preliminary report. Radiol Med 2005;110:69-76.  Back to cited text no. 21
[PUBMED]    
22.Lyshchik A, Higashi T, Asato R, Tanaka S, Ito J, Hiraoka M, et al. Cervical lymph node metastases: Diagnosis at sonoelastography--initial experience. Radiology 2007;243:258-67.  Back to cited text no. 22
[PUBMED]  [FULLTEXT]  

Top
Correspondence Address:
Ioana Andreea Gheonea
Petru Rares Street, No 2, Craiova - 200349
Romania
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0971-3026.90697

Rights and Permissions


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9]
 
 
    Tables

  [Table 1], [Table 2]

This article has been cited by
1 Elastography: history, principles, and technique comparison
Brian S. Garra
Abdominal Imaging. 2015;
[Pubmed] | [DOI]
2 Diagnostic Value of Elastography Using Acoustic Radiation Force Impulse Imaging and Strain Ratio for Breast Tumors
Yoon Seok Kim,Jung Gu Park,Beom Su Kim,Chung Han Lee,Dong Won Ryu
Journal of Breast Cancer. 2014; 17(1): 76
[Pubmed] | [DOI]
3 Incremental value of real-time ultrasound elastography in differentiating breast masses
Rania E. Mohamed,Khalid A. Abo-Dewan
The Egyptian Journal of Radiology and Nuclear Medicine. 2014; 45(2): 605
[Pubmed] | [DOI]
4 Gray scale histogram analysis of solid breast lesions with ultrasonography: can lesion echogenicity ratio be used to differentiate the malignancy?
Bekir Erol,Taylan Kara,Cemil Gürses,Rojbin Karakoyun,Mert Köroglu,Dinç Süren,Nurullah Bülbüller
Clinical Imaging. 2013; 37(5): 871
[Pubmed] | [DOI]
5 Evaluation of cervical stiffness during pregnancy using semiquantitative ultrasound elastography
E. Hernandez-Andrade,S. S. Hassan,H. Ahn,S. J. Korzeniewski,L. Yeo,T. Chaiworapongsa,R. Romero
Ultrasound in Obstetrics & Gynecology. 2013; 41(2): 152
[Pubmed] | [DOI]
6 Current Breast Imaging Modalities, Advances, and Impact on Breast Care
Evelyn M. Garcia,Erik S. Storm,Lisa Atkinson,Eileen Kenny,Lisa S. Mitchell
Obstetrics and Gynecology Clinics of North America. 2013; 40(3): 429
[Pubmed] | [DOI]
7 Evaluation of cervical stiffness during pregnancy using semiquantitative ultrasound elastography
Hernandez-Andrade, E. and Hassan, S.S. and Ahn, H. and Korzeniewski, S.J. and Yeo, L. and Chaiworapongsa, T. and Romero, R.
Ultrasound in Obstetrics and Gynecology. 2013; 41(2): 152-161
[Pubmed]
8 La elastografía: una nueva aplicación de la ecografía. ¿Cuál es su utilidad clínica?
F. Guzmán Aroca,D. Abellán Rivera,M. Reus Pintado
Radiología. 2012;
[Pubmed] | [DOI]



 

Top
 
 
  Search
 
   Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Email Alert *
    Add to My List *
* Registration required (free)  


    Abstract
   Introduction
    Materials and Me...
   Results
   Discussion
    References
    Article Figures
    Article Tables

 Article Access Statistics
    Viewed8537    
    Printed158    
    Emailed6    
    PDF Downloaded1002    
    Comments [Add]    
    Cited by others 8    

Recommend this journal