Differentiation of Benign from Malignant Solid Breast Masses: Conventional US versus Spatial Compound Imaging

PURPOSE: To compare prospectively the diagnostic performance of radiologists who used conventional ultrasonography (US) with that of radiologists who used spatial compound imaging for the differentiation of benign from malignant solid breast masses.

MATERIALS AND METHODS: The study was approved by the institutional review board, and informed consent was obtained. Before excisional or needle biopsy was performed, conventional US and spatial compound images were obtained in 67 patients (age range, 25–67 years; mean age, 45 years) with 75 solid breast masses (21 cancers and 54 benign lesions). Three experienced radiologists who did not perform the examinations independently analyzed US findings and indicated the probability of malignancy. Results were evaluated with κ statistics and receiver operating characteristic (ROC) analysis.

RESULTS: For US findings, the presence of calcifications was the most discordant feature (κ = 0.372) between conventional US and spatial compound imaging, followed by echotexture (κ = 0.439), boundary echo (κ = 0.496), orientation (κ = 0.518), echogenicity (κ = 0.523), shape (κ = 0.526), margin (κ = 0.569), and posterior acoustic transmission (κ = 0.669). The area under the ROC curve for conventional US was 0.79 for reader 1, 0.88 for reader 2, and 0.82 for reader 3, and the area under the ROC curve for spatial compound imaging was 0.85 for reader 1, 0.88 for reader 2, and 0.89 for reader 3. The partial area index for conventional US was 0.29 for reader 1, 0.69 for reader 2, and 0.39 for reader 3, and the partial area index for spatial compound imaging was 0.29 for reader 1, 0.65 for reader 2, and 0.39 for reader 3. The difference between the diagnostic performances of the two techniques was not significant (P > .05).

CONCLUSION: The performance of the radiologists with respect to the characterization of solid breast masses was not significantly improved with spatial compound imaging.

© RSNA, 2005

References

  • 1 Stavros AT, Thickman D, Rapp CL, Dennis MA, Parker SH, Sisney GA. Solid breast nodules: use of sonography to distinguish between benign and malignant lesions. Radiology 1995; 196: 123–134.
  • 2 Rahbar G, Sie AC, Hansen GC, et al. Benign versus malignant solid breast masses: US differentiation. Radiology 1999;213:889–894.
  • 3 Baker JA, Kornguth PJ, Soo MS, Walsh R, Mengoni P. Sonography of solid breast lesions: observer variability of lesion description and assessment. AJR Am J Roentgenol 1999;172:1621–1625.
  • 4 Entrekin RR, Porter BA, Sillesen HH, Wong AD, Cooperberg PL, Fix CH. Real-time spatial compound imaging: application to breast, vascular, and musculoskeletal ultrasound. Semin Ultrasound CT MR 2001;22:50–64.
  • 5 Lin DC, Nazarian LN, O'Kane PL, McShane JM, Parker L, Merritt CR. Advantages of real-time spatial compound sonography of the musculoskeletal system versus conventional sonography. AJR Am J Roentgenol 2002;179:1629–1631.
  • 6 Merritt CR. Technology update. Radiol Clin North Am 2001;39:385–397.
  • 7 Huber S, Wagner M, Medl M, Czembirek H. Real-time spatial compound imaging in breast ultrasound. Ultrasound Med Biol 2002;28:155–163.
  • 8 Seo BK, Oh YW, Kim HR, et al. Sonographic evaluation of breast nodules: comparison of conventional, real-time compound, and pulse-inversion harmonic images. Korean J Radiol 2002;3:38–44.
  • 9 Malich A, Marx C, Sauner D. Assessment of conventional versus real-time spatial compound imaging in breast sonography: preliminary results. J Clin Ultrasound 2003;31:59–60.
  • 10 Kwak JY, Kim EK, You JK, Oh KK. Variable breast conditions: comparison of conventional and real-time compound ultrasonography. J Ultrasound Med 2004;23:85–96.
  • 11 American College of Radiology. Breast imaging reporting and data system (BI-RADS). 3rd ed. Reston, Va: American College of Radiology, 1998.
  • 12 Landis JR, Koch GG. The measurement of observer agreement for categorical data. Biometrics 1977;33:159–174.
  • 13 Metz CE. Some practical issues of experimental design and data analysis in radiological ROC studies. Invest Radiol 1989;24:234–245.
  • 14 Metz CE. ROCKIT 0.9B software. Department of Radiology, University of Chicago, Illinois. http://xray.bsd.uchicago.edu/krl/roc_soft.htm. Accessed June 10, 2004.
  • 15 McClish DK. Analyzing a portion of the ROC curve. Med Decis Making 1989;9:190–195.
  • 16 Jiang Y, Metz CE, Nishikawa RM. A receiver operating characteristic partial area index for highly sensitive diagnostic tests. Radiology 1996;201:745–750.
  • 17 Lamb PM, Perry NM, Vinnicombe SJ, Wells CA. Correlation between ultrasound characteristics, mammographic findings and histological grade in patients with invasive ductal carcinoma of the breast. Clin Radiol 2000;55:40–44.
  • 18 Moon WK, Im JG, Koh YH, Noh DY, Park IA. US of mammographically detected clustered microcalcifications. Radiology 2000;217:849–854.
  • 19 Moon WK, Myung JS, Lee YJ, Park IA, Noh DY, Im JG. US of ductal carcinoma in situ. RadioGraphics 2002;22:269–280.
  • 20 Horsch K, Giger ML, Vyborny CJ, Venta LA. Performance of computer-aided diagnosis in the interpretation of lesions on breast sonography. Acad Radiol 2004;11:272–280.
  • 21 American College of Radiology. Breast imaging reporting and data system (BI-RADS): ultrasound. Reston, Va: American College of Radiology, 2003.

Article History

Published in print: 2005