Congenital Mesoblastic Nephroma and Trisomy 11

Cytogenetic analysis of a congenital mesoblastic nephroma (CMN) in a 1-month-old boy showed a 48,XY,+10,+11 karyotype. In this particular tumor type, chromosomal changes are found in almost all cases. Among the numerical changes, trisomy 11 stands out, whereas involvement of the long arm of chromosome 15 may be a nonrandomly occurring structural change.