[Significance of flow cytometry in the prognosis of tumors of the kidney in adults].

The DNA index was measured by flow cytometry on paraffin-embedded tissue blocks, from a series of 50 renal tumours studied retrospectively. These tumours consisted of 48 renal cell carcinomas and 1 oncocytoma. The mean follow-up was 3 years. TNM classification and Syrjanen's combined histological grading were used. There was a significant correlation between ploidy and nuclear grading (P = 0.02); between ploidy and TNM classification (72% of diploid tumours were T1 and T2, M0, N0, P = 0.01); between ploidy and development of metastases during the follow-up (71% of aneuploid tumours developed metastases, P = 0.04). In contrast, ploidy was not related with tumour differentiation (P = 0.052), and did not influence the overall long-term survival (P = 0.2). The small number of patients studied did not allow a significant survival rate to be established for each stage according to ploidy. The measurement of the DNA index by flow cytometry is prognostically useful for renal tumours, but must be compared with other prognostic parameters. Its therapeutic value will only be able to be assessed in the future; especially in conservative surgery indications, possibly in the choice of complementary therapeutic associations and even in the approach to treatment of metastases.