COMPARISON BETWEEN FLOW CYTOMETRIC AND CYTOGENETIC TUMOR-CELL DNA CONTENT USING A SIMPLE FLOW SAMPLE PREPARATION METHOD - PLOIDY COMPARISONOF 86 FRESH PEDIATRIC TUMORS

A comparison of tumor ploidy by flow cytometry (FL) and cytogenetics ( CYG) was made in 86 fresh pediatric solid (n = 47) and hematopoietic ( n = 39) tumors using simple sampling and semiautomated proprietary FL preparation methods and defined histogram interpretive criteria. Tumor karyotypes with 44-48 chromosomes were regarded as CYG diploid and ot her chromosomal complements CYG aneuploid for comparison purposes. Ave histograms were uninterpretable and nine cases failed to produce 15 o r more metaphases for karyotyping: Mean G0/G1 peak coefficients of var iation of all 86 cases were 2.7 and 3.0 for the diploid and aneuploid populations, respectively. Of the 72 eligible cases, 41 were concordan t diploid and IG concordant aneuploid with an overall concordance of 7 9 %. The DNA Index and karyotypic index correlation coefficient was 0. 92 for the 16 concordant aneuploid cases. Analysis of the 15 discordan t cases highlights the limitations of both methods and of the histogra m interpretive criteria and indicates that FL is probably more sensiti ve for detection of tumor aneuploidy as defined and detected by these methods.