title: Characterization of the epithelial components in pleomorphic adenoma of the salivary gland.
abstract: OBJECTIVE
  To clarify the cytomorphologic characteristics of luminal epithelial cells (LEC) and neoplastic myoepithelial cells (NMC) in pleomorphic adenoma (PA).
  
  
  METHODS
  Imprint cytologic smears stained with Papanicolaou stain were examined in 20 patients with PA (including recurrent cases). Immunocytochemistry was performed using the antibodies of epithelial membrane antigen (EMA) and carcinoembryonic antigen (CEA); cells positive for both CEA and EMA were interpreted as LEC and those negative as NMC.
  
  
  RESULTS
  LEC were found in 9 of 20 cases as cell clusters in various shapes or as isolated cells with ample cytoplasm. NMC were classified into four types according to their visual patterns and cytoplasmic features: type A, isolated cells with ample cytoplasm; type B, isolated naked cells; type C, cluster of cells with ample cytoplasm; and type D, cluster of cells with scant cytoplasm. NMC were found in all 20 cases, with an absolute incidence of 100%, 90%, 65% and 50%, respectively.
  
  
  CONCLUSIONS
  The different features of NMC (Types A-D) are essential to a specific differential diagnosis. This classification was useful to discriminate PA from other salivary gland tumors with NMC.
authors.affiliation: Department of Pathology, Kurume University Hospital, Kurume University School of Medicine, Asahimachi, Kurume, Japan.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Kawahara
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Harada
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Kage
authors.forename: Toshiro
authors.initials: T
authors.lastname: Yokoyama
authors.forename: Masamichi
authors.initials: M
authors.lastname: Kojiro
mesh_terms: D008949:Adenoma, Pleomorphic / Q000473:pathology*; D000293:Adolescent; D000328:Adult; D000368:Aged; D003528:Carcinoma, Adenoid Cystic / Q000473:pathology; D003593:Cytoplasm / Q000473:pathology; D003937:Diagnosis, Differential; D004847:Epithelial Cells / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009208:Myoepithelioma / Q000473:pathology*; D012468:Salivary Gland Neoplasms / Q000473:pathology*