Backgrounds: We present the results of a cytogenetic and molecular cytogenetic analysis of a series of patients with bone and soft tissue tumors. Pa tients and methods: We analyzed a cohort of 26 patients with Ewing sarcoma/PNET, 15 patients with rhabdomyosarcoma, 5 with synovial sarcoma and one patient with an undifferentiated sarcoma using the cytogenetic and molecular cytogenetic techniques M-FISH and arrayCGH.
Results: We found nonrandom chromosomal structural and numerical changes with diagnostic and prognostic relevance in most patients. Eight patients with ES/PNET had only a t(11;22)(q24;q12), eight patients had secondary aberrations as well and six had only secondary aberrations.
In the RMS patients we detected the t(1;13)(p36;q14) once and the t(2;13)(q35;q14) four times, both of them characteristic for the alveolar subtype with poor progno-sis and numerical aberrations, characteristic for the embryonal subtype, in five patients. Four patients with synovial sarcoma had the diagnostic t(X;18)(p11.2;q11.2), one of them had a complex karyotype with a complex t(X;18;21) (p11.2;q11.2;q11.2) together with t(2;5)(q24-32;p13-14) and t(12;20)(p11;q13).
We correlated the karyotype of cancer cells with histopathologic morphologic analysis, clinical outcome and foreign published results. Conclusion: Cytogenetic and molecular cytogenetic analysis is a valuable diagnostic tool in bone and soft tissue tumors, especially in less differentiated subtypes, and as such it should be an integral part of curative care.