Potential of morphometry in grading transitional cell carcinoma of the urinary bladder

The potential of morphometry in grading cases of transitional cell carcinoma of the urinary bladder was evaluated. Thirty cases of bladder cancer including all three WHO grades were studied. Three investigators measured the nuclear areas using the IBAS 1&2 image analyser system. The means, the standard deviations and the variances of the measurements were calculated. The nuclear areas covered values from 25.1 to 107.4 square micrometers, the mean +/- SD being 52.6 +/- 17.5. The total variance of measurements, including biological and methodological variation, was 304.6, and the methodological variance 10.4 (about 3.5% of the total variation). In a 3-grade grading system this would correspond to an efficiency of about 92%, and in a 2-grade system of about 96%, which are the percentages correctly graded by the grading system.