title: Clustering of breast microcalcifications: revisited.
abstract: OBJECTIVE
  To verify the diagnostic value of the traditional definition of 'clustering' of microcalcifications (more than five in the area of 1 cm(2)or 1 cm(3)) on mammography in the differential diagnosis of benign and malignant breast disease.
  
  
  METHODS
  Three radiologists without knowledge of the final pathology retrospectively counted the number of microcalcifications per 0.25 cm(2) (0.5 x 0.5 cm) unit area on mammography in 57 pathologically proven non-palpable lesions including 26 cancers and 31 benign diseases. Pleomorphism of the microcalcifications, associated architectural distortion or mass or increased density and distribution of microcalcifications were also evaluated.
  
  
  RESULTS
  The mean numbers of microcalcifications per 0.25 cm(2) were 16.4 in malignant and 16.7 in benign diseases (no statistically significant difference between the two groups). Pleomorphism of the microcalcifications, associated architectural distortion or mass or increased density were, however, important determining parameters. Clustering was more frequently observed in benign diseases.
  
  
  CONCLUSIONS
  In this study, the mean number of microcalcifications per unit area is much larger than the traditional definition of 'clustering' and clustering itself is not effective in the differential diagnosis of benign and malignant breast lesions. Imaging features other than numbers of calcification per unit area are more important in assessing the significance of mammographic clustered microcalcifications.
authors.affiliation: Department of Diagnostic Radiology, University of Ulsan, Asan Medical Center, Seoul, Korea.
authors.forename: J M
authors.initials: JM
authors.lastname: Park
authors.forename: H K
authors.initials: HK
authors.lastname: Choi
authors.forename: S J
authors.initials: SJ
authors.lastname: Bae
authors.forename: M S
authors.initials: MS
authors.lastname: Lee
authors.forename: S H
authors.initials: SH
authors.lastname: Ahn
authors.forename: G
authors.initials: G
authors.lastname: Gong
mesh_terms: D000328:Adult; D001941:Breast Diseases / Q000000981:diagnostic imaging* / Q000209:etiology; D001943:Breast Neoplasms / Q000150:complications / Q000000981:diagnostic imaging; D002114:Calcinosis / Q000000981:diagnostic imaging* / Q000209:etiology; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008327:Mammography; D008875:Middle Aged; D015588:Observer Variation; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012680:Sensitivity and Specificity