Cytogenetic abnormalities in mesoblastic nephroma: a link to Wilms' tumour?

Cytogenetic analysis of tumour material from a congenital mesoblastic nephroma is reported. Two cell lines were found, one with a normal 46,XY karyotype and the other with a hyperdiploid 51,XY karyotype, including a rearrangement of chromosome 11 at 11p15. This finding is of interest since loss of allelic heterozygosity at polymorphic 11p15 loci has been described in sporadic Wilms' tumour [1], and both cytogenetic [2] and molecular [3] changes of 11p15 are found in the Wiedemann-Beckwith syndrome, a condition with a predisposition to embryonal tumours, particularly Wilms' tumour. Our results lead us to speculate on the implications relating to the pathogenesis of this relatively benign tumour variant with respect to the current understanding of the genetics of Wilms' tumour.