Cytogenetic investigation of synchronous bilateral renal tumors

Cytogenetic investigations on synchronous bilateral renal tumors are scarce. We report our findings on 13 renal tumors from 5 patients and review the literature. In bilateral as well as in solitary tumors, cytogenetic findings in each tumor correlated with the histological patterns, i.e. combinations of trisomies for papillary renal cell carcinoma, loss of 3p-material for non-papillary renal cell carcinoma, and coincident loss of the Y chromosome and chromosome 1 in oncocytomas. Bilateral multifocal renal cell carcinomas were always of the papillary type and the karyotypes showed more or less the same numerical anomalies, with trisomies in different combinations in tumors within the same kidney as well as in both kidneys. Structural changes, in contrast, were different from tumor to tumor.