Cases Of Extraskeletal Myxoid Chondrosarcoma Research Articles

Extraskeletal Myxoid Chondrosarcoma with Rhabdoid Features, with Special Reference to Its Aggressive Behavior.

The presence of rhabdoid cells has been reported in various types of malignant neoplasms. Thirty-six cases of extraskeletal myxoid chondrosarcoma (EMC) were reviewed, and three of them revealed rhabdoid features. These cases contained cells having prominent eosinophilic globular cytoplasm, but were otherwise typical of EMC. Immunohistochemically, cytokeratin (CAM 5.2) was positive in three of 20 cases (15%), including two of the three with rhabdoid features. The rhabdoid cells were also immunostained with vimentin. The 5-year survival rate in the 26 cases with follow-up information was 73%, and the 10-year survival rate was 63%. The cases with rhabdoid features had a significantly poorer prognosis (p=0.0271). This study suggests that presence of rhabdoid features is a predictor of aggressive behavior in EMC, as it was shown to be in other mesenchymal neoplasms. Int J Surg Pathol 8(2):145-152, 2000

Parachordoma is immunohistochemically and cytogenetically distinct from axial chordoma and extraskeletal myxoid chondrosarcoma.

Parachordoma is a rare soft-tissue tumor resembling extraskeletal myxoid chondrosarcoma and chordoma. Because fewer than 30 cases have been reported and precisely characterized, we studied the clinicopathologic features of seven new cases, comparing the immunohistochemical (six cases) and cytogenetic (one case) profiles with 15 cases of chordoma and six cases of extraskeletal myxoid chondrosarcoma. Patients with these tumors ranged in age from 7 to 62 years (mean, 35 years) and included four women and three men. The tumors presented as subfascial masses of the thigh (two cases), arm (three cases), chest wall (one cases), and buttocks (one case). In six of seven cases, there was neither recurrence nor metastasis within the follow-up, which ranged from 4 months to 7 years. The tumors were composed of vague nodules of large, rounded eosinophilic cells embedded in a matrix that varied from myxoid to densely hyaline, and the latter areas occasionally resembled primitive cartilage. Transitions between the large eosinophilic cells and smaller rounded and shorter spindled ones were often noted. Multivacuolated (physaliferouslike) cells were noted in all cases but were usually few in number. The matrix stained with Alcian blue (pH 2.5), and this staining was abolished with hyaluronidase predigestion. Immunohistochemistry for a variety of cytokeratins (CKs) (8/18, 1/10, 7, and 20), epithelial membrane antigen (EMA), S-100 protein, vimentin CD34, type IV collagen, smooth muscle actin, smooth muscle myosin heavy chain, calponin, and glial fibrillary acid protein was performed. All parachordomas strongly expressed CK 8/18, but not the other cytokeratins. Additionally, they expressed EMA (five of six). S-100 protein (six of six), and vimentin (six of six) and had a linear pattern of type IV collagen immunoreactivity around nests of cells (four of five). Calponin was noted in one case, but no cases expressed smooth muscle actin, smooth muscle myosin heavy chain, or glial fibrillary acid protein. In contrast, chordoma expressed CK 8/18 (15 of 15) and CK 1/10 (14 of 15), whereas extraskeletal myxoid chondrosarcoma consistently lacked CK. Although chordoma and extraskeletal myxoid chondrosarcoma showed considerable overlap with parachordoma, with respect to EMA and S-100 protein, they infrequently displayed type IV collagen, as was seen in parachordoma. One case of parachordoma studied cytogenetically disclosed trisomy 15, and monosomies of 1, 16, and 17 in contrast to the t(9;22) reported in extraskeletal myxoid chondrosarcoma and the monosomies of 3, 4, 10, and 13 seen in chordoma. We conclude that the immunohistochemical and cytogenetic profile distinguishes parachordoma from extraskeletal myxoid chondrosarcoma and chordoma. Lack of myoepithelial markers, furthermore, suggests parachordoma is not a deeply situated adnexal tumor. Because of these differences, parachordoma is best regarded as a distinct lesion without a clear relationship to other well-characterized tumors.

Translocation (9;22)(g22;ql2) A recurrent chromosome abnormality in extraskeletal myxoid chondrosarcoma

Cytogenetic analysis of a case of extraskeletal myxoid chondrosarcoma revealed a reciprocal translocation between 9q and 22q in almost all metaphases analyzed. Structural rearrangements involving 9q and 22q have been reported previously in three cases of extraskeletal myxoid chondrosarcoma. The breakpoints on chromosomes 9 and 22 in the present case were in regions 9q22-q31 and 22q11-q12.2, respectively. The same breakpoints were present in all three previously reported cases. Thus, this recently identified rearrangement of 9q and 22q may serve as a critical cytogenetic parameter for the diagnosis and classification of extraskeletal myxoid chondrosarcoma, as well as being a primary chromosomal event in the course of development of this rare malignancy.

Chromosomal Abnormality T(9;22)(Q22;Q12) In an Extraskeletal Myxoid Chondrosarcoma Characterized By Fine Needle Aspiration Cytology, Electron Microscopy, Immunohistochemistry and Dna Flow Cytometry

A multidisciplinary approach was taken to characterize a soft tissue tumour. In smears prepared from aspirated material, uniform tumour cells, embedded in a myxoid matrix and partly arranged in a lace-like pattern, were found. Histopathology showed a lace-like pattern of cells in a matrix of hyaluronidase-stable mucins. Cytoplasmic positivity for S-100 protein was found in some tumour cells. Electron microscopic analysis revealed intracisternal aggregates of microtubules. All these features are consistent with the diagnosis of extraskeletal myxoid chondrosarcoma (EMC). DNA flow cytometry showed a diploid DNA content. Cytogenetic examination revealed the tumour karyotype 45,XY,t(2;11)(q31;p15),t(9;22)(q22.3;q12),dic(13;22)(p11;p13). Because similar 9;22-translocations have been described in two other cases of EMC, we conclude that t(9;22)(q22-31;q11-12) is a specific rearrangement in this tumour type. Cytogenetic analysis may thus be of diagnostic value in the examination of tumours with this and similar histologies.

Extraskeletal myxoid chondrosarcoma: a histochemical and immunohistochemical study.

In reviewing a large series of soft tissue sarcomas, nine cases of extraskeletal myxoid chondrosarcoma have been retrieved. These tumours, which principally presented in middle-aged adults, have been examined histochemically to determine the heteroglycan content of their myxoid matrix and immunohistochemically for the presence of S-100 protein. The principal mucopolysaccharides identified were chondroitin-4 and 6-sulphate and keratan sulphate; each of the tumours was S-100 positive. The relevance of these findings to the histogenesis and differential diagnosis of these uncommon neoplasms is discussed.

EXTRASKELETAL MYXOID CHONDROSARCOMA: A Clinicopathologic and Electron Microscopic Study

This clinicopathologic study concerns 14 cases of extraskeletal myxoid chondrosarcoma from among 603 cases of soft tissue sarcomas. The ages of the patients at the time of initial biopsy ranged from 16 to 69 years. The tumors mainly arose in the lower extremities including buttocks (10 cases), and consisted histologically in cords and strands of small acidophilic cells with occasional vacuolated cells in an abundant myxoid matrix composed of chondroitin sulfate. Electron microscopy in four revealed a continuum of cell differentiation of the tumor cells from chondroblastic cell to undifferentiated mesenchymal cell. Morphological studies indicated that the extraskeletal myxoid chondrosarcoma included so-called chordoid sarcoma, as a variant.