title: Determination of ploidy and steroid receptor status in breast cancer by laser scanning cytometry.
abstract: BACKGROUND
  Measurements on DNA content and steroid receptor status in breast cancer are of great clinical interest. Objective determination of estrogen and progesterone receptor expression should help to define the lowest levels of positivity still responding to adjuvant antihormonal therapy. For this purpose, a simple protocol for laser scanning cytometry is presented.
  
  
  METHODS
  Analysis of 54 routine breast cancer samples was performed by laser scanning cytometry (LSC). To obtain single cell preparations from fresh tumor tissue, slides were prepared using the Cervisoft cytological device. Exact determination of tumor cell DNA content was done by referring to the CD45-positive tissue leukocyte fraction as the internal diploid reference cell population. Steroid receptor-expressing cells were detected by indirect immunolabeling.
  
  
  RESULTS
  Indirect immunofluorescence allowed the best quantification of both the estrogen and progesterone receptor-expressing cell fractions by LSC. The number of receptor-expressing cells could be given in percentage. For comparison, the 10% cutoff value was used to determine receptor positivity.
  
  
  CONCLUSIONS
  LSC enabled a simple, reliable, and inexpensive determination of DNA index and steroid receptor expression in breast cancer specimens by objective criteria.
authors.affiliation: Institute of Pathology Bonn-Duisdorf, Bonn, Germany. reinhard@bollmann.com
authors.forename: Reinhard
authors.initials: R
authors.lastname: Bollmann
authors.forename: Robert
authors.initials: R
authors.lastname: Torka
authors.forename: Jörg
authors.initials: J
authors.lastname: Schmitz
authors.forename: Magdolna
authors.initials: M
authors.lastname: Bollmann
authors.forename: Gábor
authors.initials: G
authors.lastname: Méhes
mesh_terms: D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D002277:Carcinoma / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D004247:DNA / Q000378:metabolism*; D005260:Female; D005455:Fluorescent Antibody Technique / Q000295:instrumentation / Q000379:methods; D006801:Humans; D019044:Image Cytometry / Q000295:instrumentation / Q000379:methods*; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation / Q000379:methods; D018613:Microscopy, Confocal / Q000295:instrumentation / Q000379:methods*; D011003:Ploidies; D011960:Receptors, Estrogen / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*; D015203:Reproducibility of Results
chemical_list: D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D004247:DNA