PLOIDY ANALYSIS ON WILMS-TUMOR TOUCH IMPRINTS USING ETHIDIUM-BROMIDE AND AUTOMATED IMAGE-ANALYSIS INTEGRATED CONFOCAL LASER-SCANNING MICROSCOPY

Although image analysis (IA) is increasingly being used to quantitate nuclear DNA, comparative data between fluorescence methods of IA and f low cytometry (FCM) is limited. In this study fluorescence IA was comp ared with FCM data in a series of Wilms' tumour touch preparations. Ai rdried touch imprints that had previously been Giemsa stained were res tained with ethidium bromide. Confocal fluorescence images were obtain ed with a confocal laser scanning microscope and assessed by a fully a utomated IA package. Data was collected from 400 nuclei per imprint. T he resulting DNA histograms were analysed and ploidy status and DNA in dices determined using standard criteria. Results were compared with t hose derived from FCM analysis of nuclear suspensions, Ten of twelve t umours were concordant by both techniques. However in two cases assess ed as diploid by FCM, IA identified aneuploidy. Excellent correlation between DNA indices as assessed by both techniques was observed (r=0.9 87), In the three cases for which both unstained and Giemsa stained to uch imprints were available for IA, the histogram configurations did n ot differ significantly. Fluorescence IA is an accurate and sensitive technique for DNA quantitation, which appears at least comparable to F CM assessment and which has a number of important advantages.