title: Invasive lobular carcinoma of the breast with osteoclastlike giant cells. A case report.
abstract: BACKGROUND
  Cytologic descriptions of invasive lobular carcinoma of the breast with osteoclastlike giant cells (OGCs) are exceedingly rare. Clinically, breast carcinoma with OGCs can be confused with fibroadenoma. The histogenesis of OGCs has been the subject of debate.
  
  
  METHODS
  A 48-year-old female presented with a 1.5-cm, well-demarcated, firm, non-tender, mass involving the right breast. Fine needle aspiration biopsy (FNAB) showed the characteristic combination of relatively small, uniform carcinoma cells containing conspicuous intracytoplasmic lumina and numerous reactive multinucleated giant cells. OGCs were reactive for KP-1 and not stained with MIB-1.
  
  
  CONCLUSIONS
  The cytologic appearance of invasive lobular carcinoma with OGCs is characteristic. FNAB permits diagnosis of this rare type of breast carcinoma. Our study supported a histiocytic nature of the OGCs. OGCs were considered not actively proliferated cells.
authors.affiliation: Department of Clinical Laboratory, Kochi Medical School, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Takahashi
authors.forename: T
authors.initials: T
authors.lastname: Moriki
authors.forename: M
authors.initials: M
authors.lastname: Hiroi
authors.forename: H
authors.initials: H
authors.lastname: Nakayama
mesh_terms: D034961:Antigens, Nuclear; D015415:Biomarkers; D014408:Biomarkers, Tumor / Q000032:analysis; D001943:Breast Neoplasms / Q000737:chemistry / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology*; D018275:Carcinoma, Lobular / Q000737:chemistry / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology*; D003937:Diagnosis, Differential; D005260:Female; D018226:Fibroadenoma / Q000000981:diagnostic imaging; D015726:Giant Cells / Q000473:pathology*; D006644:Histiocytes / Q000473:pathology*; D006801:Humans; D019394:Ki-67 Antigen; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000032:analysis; D014411:Neoplastic Stem Cells / Q000648:ultrastructure; D009687:Nuclear Proteins / Q000032:analysis; D010010:Osteoclasts; D014463:Ultrasonography; D014617:Vacuoles / Q000648:ultrastructure
chemical_list: D034961:Antigens, Nuclear; D015415:Biomarkers; D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D009363:Neoplasm Proteins; D009687:Nuclear Proteins