Background and procedure: During a 13-year period, 22 children were treated for rhabdomyosarcoma (RMS). In 18 of these patients chromosome analysis was attempted on material from tumor biopsies, fine needle aspiration biopsies and/or bone marrow samples.
Results: Clonal chromosome aberrations were detected in 14 cases; 7 of 9 embryonal RMS, 6 of 8 alveolar RMS and in the single case of pleomorphic RMS cytogenetic failures were more frequent in fine needle aspiration biopsies than in tumor biopsies. The characteristic t(2;13) translocation was seen in 2 alveolar RMS but not in any of the other subtypes. In 3 of the embryonal RMS hyperdiploid or hypertetraploid karyotypes with few or no structural rearrangements were seen. In all 3 cases the clinical course was relatively benign, suggesting that certain karyotypic patterns in RMS may be of prognostic significance.
Conclusions: Our results add to the evidence that cytogenetic analysis should be an integral part of the diagnostic examinations of children with RMS.