Correlation between clinicopathological features and karyotype in spindle cell sarcomas - A report of 130 cases from the CHAMP study group

Soft-tissue tumors have proved to be a fruitful area for the identification of reproducible cytogenetic aberrations, especially among pediatric round- cell sarcomas and Lipomatous tumors. Thus far, however, data regarding sarc omas of monomorphic spindle cell type have been limited and somewhat disapp ointing, with the notable exception of synovial sarcoma. As part of an ongo ing international collaborative study, 130 karyotyped spindle-cell sarcomas were reviewed and classified histologically, without knowledge of the clin ical and karyotypic data, with the aim of identifying objective correlation s between morphology, karyotype, and clinical parameters. Clonal chromosoma l abnormalities were identified in 82 cases studied (63%), but only in the group of synovial sarcomas was there clear correlation between the cytogene tic findings, in the form of a consistent t(X;18)(p11;q11), and morphology, Among leiomyosarcomas (41 cases) and malignant peripheral nerve sheath tum ors (MPNSTs; 27 cases) as well as in individual examples of rarer entities, there was a general tendency for karyotypic complexity associated with fre quent loss or rearrangement of chromosome arms 1p, 10p, 11q, 12q, 17p, and 22q. Rearrangements of 17q (the region of the NF1 gene) were seen in 9/27 ( 33%) of MPNSTs, Among nine cases of solitary fibrous tumor (in which previo us cytogenetic data are very limited) no consistent aberrations were identi fied. We conclude that, with the exception of synovial sarcoma, most spindl e-cell sarcomas share with pleomorphic sarcomas the tendency for karyotypic complexity. There was no indication (in most of these lesions) that detect able cytogenetic aberrations could either facilitate their diagnosis or hel p to determine prognosis. There is a clear need to further study and unders tand the significance of multiple chromosomal abnormalities in this group o f mesenchymal neoplasms with the particular goal of determining their role in the process of turner development.