Abstract
Introduction: Chromosomal analysis is becoming increasingly useful in the diagnosis and management of bone and soft-tissue sarcomas. The identification of chromosomal aberrations such as translations, deletions, additions of a part or whole chromosome, and other markers are associated with specific tumor subtypes.
Material and Methods: Between 1998 and 2000, 78 bone and soft-tissue tumors were analyzed. Cytogenetic analysis was carried on a short-term cultured tissues by G-banding FISH and SKY procedures, as needed. Histopathological diagnoses included osteosarcoma – 16, Ewing’s sarcoma – 13, synovial sarcoma – 4, rhabdomyosarcoma – 4 (alveolar – 3, embryonal – 1), liposarcoma – 3, extra-abdominal fibromatosis – 3, alveolar soft part sarcoma – 12, and other soft-tissue sarcoma – 12. Other diagnoses included 8 hematological malignancies and 13 benign tumors.
Results: Eight of the 16 osteosarcomas studies demonstrated complex hyperploid karyotypes compatible with the diagnosis of high-grade osteosarcoma. In most Ewing’s sarcoma, including three cases with a typical t(11;22) translocation, other chromosomal abnormalities such as trisomies of chromosomes 5,6,8, and 14 were observed. Three of the four synovial sarcomas had the typical t(X;18)(p11.2;q11.2) translocation. One of the synovial sarcomas was initially diagnosed on a histopathological basis as Ewing’s sarcoma but the cytogenetic analysis showed a complex X;18 translocation and led to change in diagnosis and related treatment. Only one of the alveolar rhabdomyosarcomas demonstrated the typical t(2;13)(q35;q14) translocation, while hypertetraploid set with double minutes (dmin) was detected in the other two cases. By using SKY, chromosome 1 was determined as the origin of one of the dmins, suggesting that PAX7 amplification could be involved in the pathogenesis of this tumor.
Conclusions: Cytogenetic analysis of bone and soft-tissue tumors are of important clinical value for accurate diagnosis of tumor type. It can also provide information suggesting the pathogenesis of these tumors.
The abstracts were prepared by Orah Naor. Correspondence should be addressed to him at the Israel Orthopaedic Association, PO Box 7845, Haifa 31074, Israel.
