Ossifying fibromyxoid tumor of soft parts: report of a case with novel cytogenetic findings

A slowly growing rumor of the left thenar region in a 40-year-old man had t he classic features of an ossifying fibromyxoid tumor of soft parts, includ ing an incomplete shell of lamellar bone; a center composed of nodular aggr egates of small spindled. oval, and stellate cells in abundant myxoid strom a; and strong expression of vimentin, S-100, and neuron-specific enolase by the tumor cells. Clonal chromosomal abnormalities included loss of a chrom osome 6, extra material of unknown origin attached to the long arm of chrom osome 12, and an unbalanced translocation involving the short arm of a chro mosome 6 and the long arm of a chromosome 14. The karyotype was interpreted as 45,XY, der(6,14)(p10;q10),add(12)(q24.3). The chromosomal abnormalities suggest osteochondroblastic rather than neuronal or schwannian lineage. (C ) 2001 Elsevier Science Inc. All rights reserved.