Isochromosomes 7q and 17q in Wilms Tumor

We report the cytogenetic findings in a Wilms tumor from a 4-year-old boy. Karyotypic analysis revealed isochromosomes of 7q and 17q as coexisting clonal aberrations. The finding is notable in view of recent reports of i(7q) as a nonrandom event in Wilms tumor and the emerging evidence for genetic heterogeneity in this tumor.