title: Characterization of benign and malignant solid breast masses: comparison of conventional US and tissue harmonic imaging.
abstract: OBJECTIVE
  To prospectively compare the diagnostic performance of radiologists by using conventional ultrasonography (US) and tissue harmonic imaging for the differentiation of benign from malignant solid breast masses, with histologic results used as the reference standard.
  
  
  METHODS
  The study was approved by the institutional review board, and informed consent was obtained from all patients. Images were obtained with conventional US and tissue harmonic imaging in 88 patients (age range, 25-67 years; mean age, 45 years) with 91 solid breast masses (30 cancers and 61 benign lesions) before excisional or needle biopsy. Three experienced radiologists, who did not perform the examinations, independently analyzed the US findings and provided a level of suspicion to indicate the probability of malignancy. Results were evaluated by using kappa statistics and receiver operating characteristic (ROC) analyses.
  
  
  RESULTS
  Regarding the descriptions of US findings, echogenicity (kappa=0.205) was the most discordant between conventional US and tissue harmonic imaging, followed by margin (kappa=0.495), lesion boundary (kappa=0.495), calcifications (kappa=0.537), posterior acoustic transmission (kappa=0.546), echotexture (kappa=0.586), shape (kappa=0.591), and orientation (kappa=0.594). The area under the ROC curve (Az) for conventional US and tissue harmonic imaging was 0.84 and 0.79, respectively, for reader 1; 0.88 and 0.85, respectively, for reader 2; and 0.91 and 0.89, respectively, for reader 3. The overall Az value for the three readers was 0.88 for conventional US and 0.84 for tissue harmonic imaging (95% confidence interval: -0.0950, 0.1646; P=.595).
  
  
  CONCLUSIONS
  The performance of the radiologists with respect to the characterization of solid breast masses as benign or malignant was not significantly improved with tissue harmonic imaging.
authors.affiliation: Department of Radiology, Boramae Municipal Hospital, and Department of Radiology and Clinical Research Institute, Seoul National University Hospital, Korea.
authors.forename: Joo Hee
authors.initials: JH
authors.lastname: Cha
authors.forename: Woo Kyung
authors.initials: WK
authors.lastname: Moon
authors.forename: Nariya
authors.initials: N
authors.lastname: Cho
authors.forename: Sun Mi
authors.initials: SM
authors.lastname: Kim
authors.forename: Seong Ho
authors.initials: SH
authors.lastname: Park
authors.forename: Boo-Kyung
authors.initials: BK
authors.lastname: Han
authors.forename: Yeon Hyeon
authors.initials: YH
authors.lastname: Choe
authors.forename: Jeong Mi
authors.initials: JM
authors.lastname: Park
authors.forename: Jung-Gi
authors.initials: JG
authors.lastname: Im
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000145:classification* / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008875:Middle Aged; D015588:Observer Variation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016217:Ultrasonography, Mammary / Q000379:methods