Does DNA flow cytometry give useful prognostic information in renal parenchymal adenocarcinoma?

DNA ploidy and S-phase fraction (SPF) were measured by flow cytometry on 381 paraffin blocks from 93 unselected primary renal parenchymal adenocarcinomas (RPA). The results were compared with tumour grade and T category and patient survival, with a mean follow-up of 87 months. Only 21% of the tumours were uniformly diploid and ploidy was heterogeneous in 49% of cases. DNA ploidy and SPF were significantly associated with grade, but not T category of disease. Both flow cytometric parameters were significantly related to survival in a univariate analysis. However, when tumour grade was taken into account, both DNA ploidy and SPF lost their prognostic significance. Thus, neither of these parameters gave prognostic information additional to that provided by tumour grade in unselected cases of primary RPA.