ANALYSIS OF MULTIPLE RENAL-CELL ADENOMAS AND CARCINOMAS SUGGESTS ALLELIC LOSS AT 3P21 TO BE A PREREQUISITE FOR MALIGNANT DEVELOPMENT

Multiple renal cell rumours from three unrelated patients have been an alysed for loss of heterozygosity of 3p, mutation of VHL, and chromoso me 7 and 17 imbalances, Loss of 3p alleles is characteristic for clear cell type tumours and the combination of +7, +17 for chromophilic cel l type rumours. Thus, we could classify adenomas and carcinomas of til e three patients according to the genomic patterns of the tumours. Ade nomas appeared to be mostly of the chromophilic cell type. In some ade nomas, however, allelic losses of chromosome 3 were detected, pointing to a clear cell phenotype. irrespective of showing loss or retention of the 3p25 region, none of the adenomas had a VHL mutation. Therefore , inactivation of VHL does not seem to be an early event in the develo pment of renal cell rumours. Results of an analysis of regions of loss and retention of alleles of 3p markers in multiple rumours of the ind ividual patients suggest that losses at either 3p25 or 3p12-p14 are as sociated with adenomas. Additional loss at 3p21 is most likely require d to lead to development of a more malignant clear cell carcinoma. (C) 1997 Wiley-Liss, Inc.