Determination of ploidy and steroid receptor status in breast cancer by laser scanning cytometry.
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.
Bollmann
Reinhard
R
Institute of Pathology Bonn-Duisdorf, Bonn, Germany. reinhard@bollmann.com
Torka
Robert
R
Schmitz
Jörg
J
Bollmann
Magdolna
M
Méhes
Gábor
G
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
D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D004247:DNA