Isochromosome 7q in adult Wilms' tumor.

We describe cytogenetic and histologic findings in a Wilms' tumor resected from a 37-year-old man. The tumor karyotype was 45,X,-Y,i(7)(q10). These findings are notable because overrepresentation of chromosome 7 long arm material, i(7)(q10) in particular, has been described recently as a nonrandom event in pediatric Wilms' tumors. The present case suggests a shared genetic pathway in the initiation or progression of some pediatric and adult Wilms' tumors.