MOLECULAR DIFFERENTIAL-DIAGNOSIS OF RENAL-CELL CARCINOMAS BY MICROSATELLITE ANALYSIS

Recent application of molecular cytogenetic techniques has resulted in a new type of genetic classification of renal cell tumors. The key as pect of the novel diagnostic concept is reflected by biologically dist inct entities, each characterized by a specific combination of genetic changes. To work out a diagnostic/prognostic approach, we have applie d polymorphic microsatellite markers for a quick analysis, based on po lymerase chain reaction, of 82 tumor specimens We compared the results to previously, evaluated cytogenetic and histological data, ALE nonpa pillary and chromophobe renal cell carcinomas, which make up approxima tely 90% of all malignant renal cell tumors, and a subset of renal onc ocytomas were correctly diagnosed by detection of loss of heterozygosi ty at chromosomal sites 1, 2, and 3p. Allelic losses at chromosomal re gions 8p, 9p, and 14q are associated with an advanced pathological sta ge of nonpapillary renal cell carcinomas. A loss of heterozygosity at chromosomes 6, 10, 13, 17, and 21, in addition to those at chromosomes 1 and 2, confirm the diagnosis of chromophobe renal cell tumors. Usin g this approach, the differential diagnosis of renal cell tumors could be carried oat within 1 or 2 days.