[Impulse cytophotometric studies on DNA in bladder carcinoma]

The applicability and the significance of quantitative cellular DNA-estimations by rapid-flow cytofluorometric techniques are discussed for newly diagnosed tumours and in the treatment of carcinoma in situ of the bladder. From the DNA-histograms, the degree of ploidy and the proportion of S-phase cells, indicating the proliferation activity of the tumours, are determined. Diploid DNA-patterns are found in 60% of T 1-tumours while the other tumours, including carcinoma in situ, are almost exclusively aneuploid. With few exception, Grade 1-tumours are diploid and Grade 3-tumours are aneuploid; the dividing line between diploid and aneuploid DNA-patterns passes through Grade 2-tumours 60% of which are diploid and 40% aneuploid. Among the aneuploid tumours, the tetraploid cases exhibit the least malignant characteristics. The aneuploid non-tetraploid tumours increase in malignancy the more they deviate from tetraploidy. A possible explanation is the observed increase in the number of S-phase-cells correlated to the deviation from tetraploidy. The DNA-measurements have also been used for the objective assessment of therapeutic results in cases of carcinoma in situ treated by local instillation of adriamycine.