Cellular Heterogeneity In Renal Cell Carcinoma.
1R. De Vita, *M. G. Grollino, *P. Eleuteri, 1D. Cavallo, 1G. Calugi, 1D. Pomponi *M. Gallucci and *F. Di Silverio *Environmental Dept. ENEA Casaccia, Rome, *H "Cristo Re" Rome, Univ. "La Sapienza" Rome, Italy.
Intratumor heterogeneity is a characteristic of all tumors with biological and clinical implications. It is proposed as the condition for the evolution of the single neoplasm and for the origin of intertumoral and intratumoral variability. In order to evaluate the intratumoral heterogeneity of renal cell carcinomas, we studied 125 cases of these tumors by flow cytometry (FCM). FCM analysis evidenced that 64% of renal carcinomas resulted aneuploid and 25% of these were multiclonal. Multiple biopsies were taken from larger tumors and the 35% displaied different D1 values between tumor core and periphery. Some of these cases were analysed with FISH to obtain further information at the single cell level. The ploidy of chromosomes 7, 11, 17 and 18 was investigated utilizing specific probes to have a better characterization of these tumors. We found evaluable and comparable results in every case of renal carcinoma analyzed. Heterogeneity frequentely found in renal cell carcinoma could be a possible marker for the degree of genomic instability and could furnish relevant clinical informations.