Karyometric investigations on urinary bladder carcinoma, correlated to histopathological grading

The aim of this study is to provide karyometric data which may be of value in the grading of urinary bladder tumours. For this purpose 27 biopsies were studied: four from normal bladder mucosae, eleven from grade I tumours, six from grade II tumours and another six from grade III tumours, according to a I-IV scale. After standardized fixation and plastic embedding, semithin sections were used for light microscopic stereology. Mean profile areas and mean volume densities of the nuclei tended to be higher in the more malignant cases. The nuclear volume densities were significantly higher in grade II than in grade I. The most important finding relates to the large nuclear profiles (greater than 90 microns 2), which were found almost exclusively in grade III tumours. Simple measurements of nuclear size can thus provide objective data to aid in the diagnostic procedure.