DNA CYTOMETRIC AND INTERPHASE CYTOGENETIC ANALYSES OF PARAFFIN-EMBEDDED HYDATIDIFORM MOLES AND HYDROPIC ABORTIONS

The combined application of DNA cytometric and interphase cytogenetic analyses was used to find objective criteria for the differential diag nosis of complete hydatidiform mole, partial hydatidiform mole and hyd ropic abortion. DNA ploidy and G0/G1 exceeding rates were determined u sing image and flow cytometric analyses on paraffin-embedded tissues o f 166 cases: 71 cases of complete mole, 20 cases of partial mole, and 75 cases of abortions. To determine the existence and histological dis tribution of cell subpopulations with numerical chromosome aberrations , interphase cytogenetic analysis using probes specific for chromosome s 1, X, and Y was applied to paraffin tissue sections of 23 cases: 12 cases of complete mole, 3 cases of partial mole, and 8 cases of aborti ons. In contrast to previously reported findings that complete moles a re diploid, the results of this study showed that complete moles are D NA-polyploid (96 per cent), with high G0/G1 exceeding rates and a high frequency of numerical chromosomal aberrations in the trophoblast hyp erplasia. The majority of the partial moles were DNA-triploid (55 per cent). This study, however, also showed the presence of DNA-polyploid partial moles (30 per cent). Abortions were DNA-diploid (60 per cent) or DNA-triploid (39 per cent). DNA cytometric analysis, especially ima ge DNA cytometric analysis with determination of the G0/G1 exceeding r ate, and interphase cytogenetic analysis provide objective measurement s which are contributory in the differential diagnosis between complet e mole, partial mole, and hydropic abortion.