Flow cytometric S-phase fraction measurement in breast carcinoma: Influence of software and histogram resolution.
BACKGROUND
S-phase fraction (SPF) measurement by flow cytometry is a clinically useful prognostic factor in patients with breast carcinoma. Standardized SPF determination is essential. As part of a multicenter study, we evaluated the influence of the choice of software and histogram resolution (256, 512, or 1,024 channels) on SPF quantification.


METHODS
One hundred thirty-three DNA histograms were analyzed in three laboratories with Modfit 5.2, Modfit LT, and Multicycle AV software. Strict rules for histogram interpretation and software management were applied. The following five options were compared: MF 5.2 1024, MF 5.2 256, MF LT 256, MC AV 256, and MC AV 512.


RESULTS
In the DNA diploid and aneuploid groups, SPF distributions were not statistically different among the five options. Excellent quantitative correlations were obtained between pairs of options. When using tertiles as cutpoints for SPF classification, concordance rates ranged from 79.7% to 93.2% for DNA diploid samples and from 87.8% to 95.9% for DNA aneuploid samples, the best results being obtained with software working with a similar histogram resolution.


CONCLUSIONS
Standardized use of commercially available software, including the choice of histogram resolution, provides comparable SPF results.
Laboratoire de Cancérologie, INSERM EMI 0211, Hôpital Bretonneau, CORAD, 2 boulevard Tonnellé, 37044 Tours cedex, France. m.jourdan@chu-tours.fr
Marie-Lise
ML
Jourdan
Magali
M
Ferrero-Poüs
Frédérique
F
Spyratos
Sylvie
S
Romain
Pierre-Marie
PM
Martin
Agnès
A
Chassevent
D001943:Breast Neoplasms / Q000473:pathology*; D002277:Carcinoma / Q000473:pathology*; D004273:DNA, Neoplasm / Q000032:analysis; D005260:Female; D005434:Flow Cytometry / Q000379:methods* / Q000592:standards; D006801:Humans; D011003:Ploidies; D011379:Prognosis; D015203:Reproducibility of Results; D016196:S Phase; D012985:Software Design
D004273:DNA, Neoplasm