title: Scoring system based on BI-RADS lexicon to predict probability of malignancy in suspicious microcalcifications.
abstract: OBJECTIVE
  To develop a scoring system allowing quantification of the probability of malignancy of suspicious microcalcifications based on Breast Imaging Reporting and Data System (BI-RADS).
  
  
  METHODS
  A total of 163 microcalcification lesions surgically excised in 147 women (aged 28-65 years) were included. Two radiologists independently reviewed each lesion with BI-RADS (4th edition). The interobserver agreement and positive predictive value (PPV) for each descriptor were determined and multivariate analysis was used to develop a scoring system. The scores were compared between benign and malignant lesions and among BI-RADS categories by using the two-sample t-test or the analysis of variance. To assess the discriminative power of the scoring system, the area under the receiver-operating characteristic curve (AUC) and cutoff values for categorization were determined. For the test of the scoring system, the validation data set from a different facility was applied.
  
  
  RESULTS
  Interobserver agreement was fair to moderate for distribution, morphology, and category (κ = 0.45, 0.40, and 0.37). PPVs were significantly different among BI-RADS descriptors and categories (P < 0.0001). Of the scoring system developed, the AUC was 0.75. The scores between benign and malignant lesions were significantly different. By means of cutoff values, PPV in category 4a, 4b, 4c, and 5 was 7.0%, 15.0%, 44.8%, and 83.3%, respectively. For the validation data set, the AUC was 0.79 and the PPV in category 4a, 4b, 4c, and 5 was 9.4%, 24.1%, 62.5%, and 80.0%, respectively.
  
  
  CONCLUSIONS
  In suspicious microcalcifications, our scoring system based on BI-RADS (4th edition) could help to derive a specific final category with good stratification of the probability of malignancy.
authors.affiliation: Department of Radiology, Research Institute of Radiological Science, Yonsei University College of Medicine, Seoul, South Korea.
authors.forename: Ji Hyun
authors.initials: JH
authors.lastname: Youk
authors.forename: Eun Ju
authors.initials: EJ
authors.lastname: Son
authors.forename: Jeong-Ah
authors.initials: JA
authors.lastname: Kim
authors.forename: Hee Jung
authors.initials: HJ
authors.lastname: Moon
authors.forename: Min Jung
authors.initials: MJ
authors.lastname: Kim
authors.forename: Chung Hyun
authors.initials: CH
authors.lastname: Choi
authors.forename: Eun-Kyung
authors.initials: EK
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D019540:Area Under Curve; D001707:Biopsy, Needle; D001941:Breast Diseases / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D001943:Breast Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D002114:Calcinosis / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D002278:Carcinoma in Situ / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D018270:Carcinoma, Ductal, Breast / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D006965:Hyperplasia / Q000473:pathology; D016015:Logistic Models; D008327:Mammography / Q000592:standards; D008875:Middle Aged; D011237:Predictive Value of Tests; D011336:Probability; D012372:ROC Curve; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity