DNA-aneuploidy as marker for neoplasia in G1-urothelial carcinomas

Biopsies from 60 grade-1 urothelial carcinomas and 50 normal bladder mucosae have been investigated by DNA-image-cytometry after enzymatic cell separation to determine the diagnostic sensitivity of DNA-aneuploidy for the identification of low grade urothelial neoplasia. Two different modes to detect DNA-aneuploidy were compared: the conventional application of a threshold at 2.2c for the modal DNA value and the use of the Kolmogoroff-Smirnow (KS) test to compare GO/1 phase fractions of the cells under analysis and the internal reference cells. Whereas the specificity for both types of analysis was 100%, the sentitivity of the latter method was 73.3% compared to 48.3% of the conventional procedure. Therefore, the application of the KS-test for the identification of DNA- stemlines as aneuploid results in an increased detection rate was compared with the conventional threshold procedure. The high prevalence of DNA- stemline aneuploidy even in low grade urothelial cancers may qualify this marker as a possible aid in the cytologic evaluation of urine and bladder washings.