title: Mammographic microcalcifications and breast cancer tumorigenesis: a radiologic-pathologic analysis.
abstract: BACKGROUND
  Microcalcifications (MCs) are tiny deposits of calcium in breast soft tissue. Approximately 30% of early invasive breast cancers have fine, granular MCs detectable on mammography; however, their significance in breast tumorigenesis is controversial. This study had two objectives: (1) to find associations between mammographic MCs and tumor pathology, and (2) to compare the diagnostic value of mammograms and breast biopsies in identifying malignant MCs.
  
  
  METHODS
  A retrospective chart review was performed for 937 women treated for breast cancer during 2000-2012 at St. Michael's Hospital. Demographic information (age and menopausal status), tumor pathology (size, histology, grade, nodal status and lymphovascular invasion), hormonal status (ER and PR), HER-2 over-expression and presence of MCs were collected. Chi-square tests were performed for categorical variables and t-tests were performed for continuous variables. All p-values less than 0.05 were considered statistically significant.
  
  
  RESULTS
  A total of 937 patient charts were included. About 38.3% of the patients presented with mammographic MCs on routine mammographic screening. Patients were more likely to have MCs if they were HER-2 positive (52.9%; p < 0.001). There was a significant association between MCs and peri-menopausal status with a mean age of 50 (64%; p = 0.012). Patients with invasive ductal carcinomas (40.9%; p = 0.001) were more likely to present with MCs than were patients with other tumor histologies. Patients with a heterogeneous breast density (p = 0.031) and multifocal breast disease (p = 0.044) were more likely to have MCs on mammograms. There was a positive correlation between MCs and tumor grade (p = 0.057), with grade III tumors presenting with the most MCs (41.3%). A total of 52.2% of MCs were missed on mammograms which were visible on pathology (p < 0.001).
  
  
  CONCLUSIONS
  This is the largest study suggesting the appearance of MCs on mammograms is strongly associated with HER-2 over-expression, invasive ductal carcinomas, peri-menopausal status, heterogeneous breast density and multifocal disease.
authors.affiliation: Department of Hematology/Oncology, St. Michael's Hospital, 30 Bond Street, Toronto, Ontario, M5B 1W8, Canada. madiha.naseem@utoronto.ca.|Faculty of Medicine, University of Toronto, 1 Kings College Circle, Toronto, ON, M5S 1A8, Canada. madiha.naseem@utoronto.ca.
authors.forename: Madiha
authors.initials: M
authors.lastname: Naseem
authors.affiliation: Horizon Health Network, The Moncton Hospital, 135 MacBeath Avenue, Moncton, New Brunswick, E1C 6Z8, Canada. Joshua.Murray@HorizonNB.ca.
authors.forename: Joshua
authors.initials: J
authors.lastname: Murray
authors.affiliation: Dana-Farber Cancer Institute, Brigham and Women's Hospital, and Harvard Medical School, 450 Brookline Avenue, Boston, MA, 02215, USA. John_Hilton@DFCI.HARVARD.EDU.
authors.forename: John F
authors.initials: JF
authors.lastname: Hilton
authors.affiliation: Faculty of Medicine, University of Toronto, 1 Kings College Circle, Toronto, ON, M5S 1A8, Canada. karamchandaj@smh.ca.|Department of Laboratory Medicine and Pathology, St. Michael's Hospital, 30 Bond Street, Toronto, ON, M5B 1W8, Canada. karamchandaj@smh.ca.
authors.forename: Jason
authors.initials: J
authors.lastname: Karamchandani
authors.affiliation: Faculty of Medicine, University of Toronto, 1 Kings College Circle, Toronto, ON, M5S 1A8, Canada. MuradaliD@smh.ca.|Department of Medical Imaging, St. Michael's Hospital, 30 Bond Street, Toronto, ON, M5B 1W8, Canada. MuradaliD@smh.ca.
authors.forename: Derek
authors.initials: D
authors.lastname: Muradali
authors.affiliation: Faculty of Medicine, University of Toronto, 1 Kings College Circle, Toronto, ON, M5S 1A8, Canada. FaragallaH@smh.ca.|Department of Laboratory Medicine and Pathology, St. Michael's Hospital, 30 Bond Street, Toronto, ON, M5B 1W8, Canada. FaragallaH@smh.ca.
authors.forename: Hala
authors.initials: H
authors.lastname: Faragalla
authors.affiliation: Department of Hematology/Oncology, St. Michael's Hospital, 30 Bond Street, Toronto, Ontario, M5B 1W8, Canada. cpolenz@uwaterloo.ca.
authors.forename: Chanele
authors.initials: C
authors.lastname: Polenz
authors.affiliation: Department of Hematology/Oncology, St. Michael's Hospital, 30 Bond Street, Toronto, Ontario, M5B 1W8, Canada. dolly.han@mail.utoronto.ca.
authors.forename: Dolly
authors.initials: D
authors.lastname: Han
authors.affiliation: Department of Laboratory Medicine and Pathology, St. Michael's Hospital, 30 Bond Street, Toronto, ON, M5B 1W8, Canada. Bellcd@smh.ca.
authors.forename: David C
authors.initials: DC
authors.lastname: Bell
authors.affiliation: Department of Hematology/Oncology, St. Michael's Hospital, 30 Bond Street, Toronto, Ontario, M5B 1W8, Canada. BrezdenC@smh.ca.|Faculty of Medicine, University of Toronto, 1 Kings College Circle, Toronto, ON, M5S 1A8, Canada. BrezdenC@smh.ca.
authors.forename: Christine
authors.initials: C
authors.lastname: Brezden-Masley
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D002114:Calcinosis / Q000000981:diagnostic imaging* / Q000473:pathology*; D063646:Carcinogenesis / Q000473:pathology*; D005260:Female; D006801:Humans; D008327:Mammography / Q000379:methods*; D008875:Middle Aged; D012189:Retrospective Studies