Nuclear grading of renal cell carcinomas--is morphometry necessary?

Comparative investigations of subjective with objective nuclear grading methods of renal cell carcinomas are almost completely lacking. Therefore, we graded 94 cases of this carcinomas by a simple, subjective microscopical estimation as well as by a morphogenetic measurement of nuclear area. Both procedures proved prognostically useful, but the best results were achieved by morphometry. By this method three prognostic groups of renal cell carcinoma were found, provided that the borderlines were drawn at 28 microns 2 and 60 microns 2, respectively. Particularly favourable and unfavourable cases could be separated from average ones, if the means and standard deviations of both the nuclear areas and the diameters were evaluated. Overall, morphometric nuclear analyses are highly desirable, if, for example, morphological data are to be used in the context of prognostic or therapeutic studies on renal cell carcinoma. However, there is a broad distribution of the values for individual cases so that, tumour-biologically, no exact demarcation of prognostically different groups can be expected.