Morphometry of bladder carcinoma: definition of a new variable.

In this study two measurements of nuclear size, the mean area and the size distribution curve of nuclear area, were used to differentiate between two polar groups: nuclei from non-neoplastic urothelium and nuclei from transitional cell carcinomas of bladder with a poor clinical outcome. Wide separation of these groups is necessary if a measurement is to be used to assess tumour grade where the morphometric differences are intermediate between such polar groupings. Separation between two groups was best achieved using a weighted distribution of nuclear size and this is a means of objective scoring of urothelial tumours.