[Cytophotometric studies of urinary bladder tumors of various degrees of differentiation].

With the help of the scanning microscope photometry DNA content and size of Feulgen-stained cytoblasts may be measured. On smears of 28 tumours of the urinary bladder of all degrees of differentiation in each case 200 nuclei were investigated, the DNA and surface values were applied in histograms and these were compared one with another. With increasing dedifferentiation the mean nucleus-DNA content and the spreading of DNA and surface values significantly increased. The mean size of the nuclei did not increase. Increasingly ploidy deviations appeared--clinically significant for the recidivation. With the help of the proportion of non-diploid nuclei the histo-pathological graduation could be repeatedly performed and statements could be made as to the proliferative behaviour of tumours of the same classification. The "chromatin density" of non-diploid nuclei allowed the exact separation of the papillomas (Gx2) from the carcinoma preparations. The results are discussed on the basis of the literature.