CLONAL KARYOTYPIC EVOLUTION IN AN EMBRYONAL RHABDOMYOSARCOMA WITH TRISOMY-8 AS THE PRIMARY CHROMOSOMAL ABNORMALITY

An embryonal rhabdomyosarcoma was analyzed cytogenetically. In primary cultures fed a serum-containing medium, 11 clones with karyotypic abn ormalities were found. One had trisomy 8 only. The other 10 clones had trisomy 8 as well as additional evolutionary changes that included tr isomy for part or all of chromosome 2, isochromosomes for the short an d long arms of chromosome 11, isochromosomes for the long arm of chrom osome 8, and extra copies of chromosome 8, some of which had an inters titial deletion in 8q. In those primary cultures that had grown in a c hemically defined, serum-free medium and in all passaged cultures, tri somy 8 was the only aberration. Our findings and a survey of published information point to gain of one chromosome 8 as a frequent primary k aryotypic abnormality in embryonal rhabdomyosarcomas. Trisomy for part or all of chromosomes 2 and 11 and additional gains of chromosome 8 m aterial seem to be common secondary changes. (C) 1993 Wiley-Liss, Inc.