title: Cytologic diagnosis of signet-ring cell carcinoma of the breast.
abstract: OBJECTIVE
  To examine the cytologic features of signet-ring cell carcinoma (SRCC), defined as carcinoma dominated by signet-ring cells, of the breast and to discuss problems that occur in cytodiagnosis.
  
  
  METHODS
  Five cases of SRCC of the breast were examined cytopathologically. Signet-ring cells were subclassified into intracytoplasmic lumina (ICL) type and non-ICL type. ICL type had large ICL containing mucin. Non-ICL-type cells had wide, amorphous cytoplasm diffusely dispersed with mucin.
  
  
  RESULTS
  In cases 1 and 2, fine needle aspiration biopsy (FNAB) revealed many signet-ring cells (non-ICL type), suggesting SRCC. Histologic diagnoses were ductal SRCC containing many signet-ring cells (non-ICL type). In cases 3 and 4, signet-ring cells (ICL type) were found sporadically among carcinoma cells without signet-ring features. Signet-ring cells were not regarded as the major component of the cells; thus, the cytologic diagnoses were lobular carcinoma, not otherwise specified. Pathologic diagnoses were lobular SRCC. Signet-ring cells were mostly ICL type. In case 5, most carcinoma cells on the smears showed signet-ring features (non-ICL type), suggesting SRCC. The histologic diagnosis was lobular SRCC, and signet-ring cells were mostly non-ICL type.
  
  
  CONCLUSIONS
  Ductal SRCC yielded more cellular smears as compared with lobular SRCC; therefore, cytologic diagnosis was easier in the former.
authors.affiliation: Department of Clinical Pathology, Teikyo University School of Medicine, Kanagawa, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Kamiya
authors.forename: K
authors.initials: K
authors.lastname: Mizuguchi
authors.forename: M
authors.initials: M
authors.lastname: Yoshimoto
authors.forename: M
authors.initials: M
authors.lastname: Tanaka
authors.forename: S
authors.initials: S
authors.lastname: Motegi
authors.forename: H
authors.initials: H
authors.lastname: Matushima
authors.forename: M
authors.initials: M
authors.lastname: Ishizawa
authors.forename: K
authors.initials: K
authors.lastname: Nakamura
mesh_terms: D000328:Adult; D001707:Biopsy, Needle; D001943:Breast Neoplasms / Q000737:chemistry / Q000175:diagnosis* / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000737:chemistry / Q000473:pathology; D018275:Carcinoma, Lobular / Q000737:chemistry / Q000473:pathology; D018279:Carcinoma, Signet Ring Cell / Q000737:chemistry / Q000175:diagnosis* / Q000473:pathology; D002467:Cell Nucleus / Q000648:ultrastructure; D003937:Diagnosis, Differential; D018450:Disease Progression; D005260:Female; D006801:Humans; D008875:Middle Aged; D009077:Mucins / Q000032:analysis; D009361:Neoplasm Invasiveness; D009363:Neoplasm Proteins / Q000032:analysis; D009378:Neoplasms, Multiple Primary / Q000737:chemistry / Q000175:diagnosis* / Q000473:pathology; D011379:Prognosis
chemical_list: D009077:Mucins; D009363:Neoplasm Proteins