Translocation t(9;22)(q22;q12) is a primary cytogenetic abnormality in extraskeletal myxoid chondrosarcoma

Abstract

The cytogenetic and in vitro growth characteristics of 3 cases of extraskeletal myxoid chondrosarcoma (EMC) are described. In cell culture, the tumor cells retained the immunocytochemical and ultrastructural characteristics of EMC. Cytogenetically, 2 of the cases showed an apparently identical t(9;22)(q22;q12). In one case, the t(9;22) was found together with a dup(I)(q12q44), and in the other case it was found together with several other aberrations. The third case had an inv(10)(p11.2q22) as the sole karyotypic abnormality. Of 4 cases of EMC previously analyzed, 2 showed a t(9;22)(q22;q11-12) and one case of a t(9;22;15)(q31;q12.2;q25). Thus, 5 out of 7 cases of EMC showed recombination between 9q22-31 and 22q11-12, indicating that this represents a tumor specific abnormality. The breakpoints on 22q were in all 5 cases cytogenetically indistinguishable from those seen in Ewing's sarcoma with t(11;22), clear-cell sarcoma with t(12;22), and desmoplastic small round cell tumors with t(11;22). Molecular cloning of these translocation breakpoints revealed involvement of the EWS gene (located at 22q12) in all 3 tumor types. These observations raise the intriguing question of whether the EWS gene might also be involved in the t(9;22) in EMC.

Angiomatoid Fibrous Histiocytoma: The Current Status of Pathology and Genetics

“…64,65 Primary pulmonary myxoid sarcomas bear a striking histologic resemblance to extraskeletal myxoid chondrosarcoma but lack the characteristic translocations of extraskeletal myxoid chondrosarcoma that fuse NR4A3 on chromosome 9q22 to a variety of partner genes. [66][67][68][69][70][71][72][73] Primary pulmonary myxoid sarcomas generally express only vimentin but are occasionally weakly and focally immunoreactive for epithelial membrane antigen. The reticular pattern characteristic of PPMS is sometimes seen in AFH, which may cause diagnostic confusion in AFHs arising in the pulmonary region.…”

Skeletal and extraskeletal myxoid chondrosarcoma

“…5,6 Cytogenetic studies have demonstrated the presence of a recurrent translocation t(9;22)(q22-31;q11-12) in EMC. [7][8][9][10][11][12] The t(9;22)(q22;q12) translocation appears to be pathognomonic for EMC and has not been found in other mesenchymal tumors. 7,13 It has recently been shown that this translocation results in a fusion of the EWS gene on chromosome 22 with a novel gene, designated CHN (also known as TEC or NOR1) on chromosome 9.…”

Extraskeletal myxoid chondrosarcoma of the thigh with a t(9;17) translocation

“…As cartilaginous areas are not common despite the name 'EMC', making a diagnosis based solely on histopathological findings is often difficult. At present, the number of reported cytogenetic studies of EMC remains small due to the rarity of the tumor (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21). We report an additional case of EMC and review the literature on cytogenetic studies.…”