Reproducibility of DNA ploidy and S-phase values from paraffin-embedded tissue.
OBJECTIVE
To determine the degree of variability of DNA flow cytometric results between two types of flow cytometers.


METHODS
Single-cell suspensions were made from 40 paraffin blocks of ovarian carcinoma using a modified Hedley procedure. These samples were consecutively analyzed in both Coulter's Profile II and Elite Flow cytometers. Gated and ungated data were collected and analyzed using Phoenix flow system's multicycle software.


RESULTS
There were 16 (40%) DNA diploid, 23 (58%) DNA aneuploid and 1 DNA tetraploid tumor. The degree of variability in the DNA index coefficient of variation of the G0/G1 diploid peak, percentage of S phase, percentage of G2M, percentage of debris plus percentage of clumps were compared. Excellent correlations of the results were obtained in the DNA index (r = .999) and in percentage of S phase (r = .946).


CONCLUSIONS
It is feasible to standardize variables of flow cytometric instruments to obtain reproducible results.
Elavathil
L J
LJ
Department of Pathology, McMaster University Medical Centre, Ontario, Canada.
Celebre
G
G
McFarlane
D
D
D004273:DNA, Neoplasm / Q000032:analysis*; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D010051:Ovarian Neoplasms / Q000235:genetics* / Q000473:pathology; D016612:Paraffin Embedding; D011003:Ploidies; D015203:Reproducibility of Results; D016196:S Phase
D004273:DNA, Neoplasm