title: Clinical application of S-Detect to breast masses on ultrasonography: a study evaluating the diagnostic performance and agreement with a dedicated breast radiologist.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the diagnostic performance of S-Detect when applied to breast ultrasonography (US), and the agreement with an experienced radiologist specializing in breast imaging.
  
  
  METHODS
  From June to August 2015, 192 breast masses in 175 women were included. US features of the breast masses were retrospectively analyzed by a radiologist who specializes in breast imaging and S-Detect, according to the fourth edition of the American College of Radiology Breast Imaging Reporting and Data System lexicon and final assessment categories. Final assessments from S-Detect were in dichotomized form: possibly benign and possibly malignant. Kappa statistics were used to analyze the agreement between the radiologist and S-Detect. Diagnostic performance of the radiologist and S-Detect was calculated, including sensitivity, specificity, positive predictive value (PPV), negative predictive value, accuracy, and area under the receiving operator characteristics curve.
  
  
  RESULTS
  Of the 192 breast masses, 72 (37.5%) were malignant, and 120 (62.5%) were benign. Benign masses among category 4a had higher rates of possibly benign assessment on S-Detect for the radiologist, 63.5% to 36.5%, respectively (P=0.797). When the cutoff was set at category 4a, the specificity, PPV, and accuracy was significantly higher in S-Detect compared to the radiologist (all P<0.05), with a higher area under the receiver operator characteristics curve of 0.725 compared to 0.653 (P=0.038). Moderate agreement (k=0.58) was seen in the final assessment between the radiologist and S-Detect.
  
  
  CONCLUSIONS
  S-Detect may be used as an additional diagnostic tool to improve the specificity of breast US in clinical practice, and guide in decision making for breast masses detected on US.
authors.affiliation: Department of Radiology, Severance Hospital, Research Institute of Radiological Science, Seoul, Korea.
authors.forename: Kiwook
authors.identifier: 0000-0002-8798-5038
authors.initials: K
authors.lastname: Kim
authors.affiliation: Department of Research Affairs, Biostatistics Collaboration Unit, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Mi Kyung
authors.identifier: 0000-0003-3799-0426
authors.initials: MK
authors.lastname: Song
authors.affiliation: Department of Radiology, Severance Hospital, Research Institute of Radiological Science, Seoul, Korea.
authors.forename: Eun-Kyung
authors.identifier: 0000-0002-3368-5013
authors.initials: EK
authors.lastname: Kim
authors.affiliation: Department of Radiology, Severance Hospital, Research Institute of Radiological Science, Seoul, Korea.
authors.forename: Jung Hyun
authors.identifier: 0000-0002-2100-3513
authors.initials: JH
authors.lastname: Yoon
keywords: BI-RADS; Breast; Diagnosis, computer-aided; Neoplasms; Ultrasonography