1/6. Clear cell sarcoma of soft parts: report of a case primary in the kidney with cytogenetic confirmation.Clear cell sarcoma of soft parts (CCSSP), also known as malignant melanoma of soft parts, is an aggressive tumor that usually presents in soft tissue and very rarely in small bowel. We report a case arising in the kidney of a 20-year-old man which was difficult to distinguish from Wilms' tumor. The tumor metastasized to the liver and lungs, and the patient died of disseminated disease 5 years after his initial presentation. Both the primary and metastatic tumors were composed predominantly of spindle cells with occasional more epithelioid areas that were inconsistently arranged in nests. In both primary and metastatic sites, the tumor surrounded and entrapped normal epithelial elements, mimicking the biphasic appearance of Wilms' tumor. The tumor cells, however, were positive for S-100 protein and HMB45 and negative for keratin and CD99, and cytogenetic analysis revealed a clonal abnormality, translocation t(12;22)(q13;q12), characteristic of CCSSP. This result was verified by fluorescence in situ hybridization on paraffin-embedded tissue, which demonstrated EWS gene-region rearrangement. CCSSP joins a growing list of tumors that typically arise in soft tissue (PNET, solitary fibrous tumor, and infantile/congenital fibrosarcoma), but can also present in the kidney and may be confused with primary renal tumors. awareness of this possibility and the use of ancillary studies. including immunohistochemistry, cytogenetic analysis, and fluorescence in situ hybridization, are important for accurate diagnosis.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/6. Newly established clear cell sarcoma (malignant melanoma of soft parts) cell line expressing melanoma-associated Melan-A antigen and overexpressing C-MYC oncogene.Clear cell sarcoma (CCS), malignant melanoma of soft parts, is a rare malignant tumor with a poor prognosis. In this study, a CCS cell line, designated MP-CCS-SY, was established from a metastatic tumor of a 17-year-old Japanese girl that originated in the left achilles tendon. A small number of melanosomes were detected in the cytoplasm by electron microscopy. The melanosomes immunoreacted with two melanoma-associated antibodies, HMB45 and Melan-A. A Western blot demonstrated the existence of a Melan-A antigen in this cell line. Although a t(12;22)(q13;q12), which is characteristic of CCS, was not identified by a chromosomal analysis with conventional banding techniques, fluorescence in situ hybridization analysis with painting probes of chromosomes 12 and 22 revealed the insertion of a chromosome 12 fragment into one of the long arms of chromosome 22. The chimeric EWS/ATF1 transcript was detected by the reverse transcriptase polymerase chain reaction. Extra copies and structural abnormalities of chromosome 8 were observed. Overexpression of c-myc mRNA was detected by Northern blot analysis and may have a role in malignant progression of CCS. The availability of this MP-CCS-SY cell line will help to understand the molecular biology of this malignancy and should be useful as a tool for developing an immunotherapy.- - - - - - - - - - ranking = 0.5keywords = hybridization (Clic here for more details about this article) |
3/6. Clear cell sarcoma of the stomach.AIM: Clear cell sarcoma is a high-grade sarcoma with morphological features resembling malignant melanoma. This tumour is reported to display a characteristic distribution pattern nearly always involving the extremities. We report the first case of clear cell sarcoma of the stomach. methods AND RESULTS: A 30-year-old male developed a huge tumour of the stomach, which at first glance could be considered as a poorly differentiated carcinoma. Immunohistochemical and ultrastructural examinations were consistent with a diagnosis of metastatic melanoma. However, cytogenetic examination revealed a t(12;22) translocation, specific for clear cell sarcoma. This was confirmed by fluorescence in-situ hybridization. CONCLUSION: Making a reliable diagnosis of clear cell sarcoma of the stomach requires cytogenetic or molecular diagnostic investigations, particularly to rule out metastatic melanoma. This diagnosis avoids an unnecessary search for a primary melanoma.- - - - - - - - - - ranking = 0.5keywords = hybridization (Clic here for more details about this article) |
4/6. Myxoid clear cell sarcoma.Clear cell sarcoma is a rare soft-tissue tumor presenting typically in the extremities of young adults. It has been also known as malignant melanoma of the soft parts because of the presence of melanin and cytoplasmic melanosomes. However, clear cell sarcoma is, at present, usually considered as a unique lesion because the t(12;22)(q13;q12) translocation is present only in clear cell sarcoma. Myxoid malignant melanoma is now a well-recognized morphologic variant of malignant melanoma. However, a myxoid variant of clear cell sarcoma has not been well described yet. We report a case of myxoid clear cell sarcoma occurring on the heel in a 22-year-old man. The tumor was composed of nests and fascicles of oval to fusiform cells with clear to pale eosinophilic cytoplasm, often separated by fibrous septa. The tumor cells were reactive for S-100 protein, HMB-45, and MART-1. Variably sized cysts lined by one or several layers of tumor cells were observed. alcian blue and mucicarmine stains demonstrated prominent mucin deposition in the tumor stroma and especially in the lumen of the cysts. fluorescence in situ hybridization for the Ewing sarcoma gene showed rearrangement in nearly all of the neoplastic cells.- - - - - - - - - - ranking = 0.5keywords = hybridization (Clic here for more details about this article) |
5/6. EWS-CREB1: a recurrent variant fusion in clear cell sarcoma--association with gastrointestinal location and absence of melanocytic differentiation.PURPOSE: Clear cell sarcoma (CCS) usually arises in the lower extremities of young adults and is typically associated with a t(12;22) translocation resulting in the fusion of EWS (EWSR1) with ATF1, a gene encoding a member of the cyclic amp-responsive element binding protein (CREB) family of transcription factors. CCS arising in the gastrointestinal tract is rare and its pathologic and molecular features are not well defined. EXPERIMENTAL DESIGN: We report a novel variant fusion of EWS to CREB1, a gene at 2q32 encoding another CREB family member highly related to ATF1, detected in three women with gastrointestinal CCS. All three cases contained an identical EWS-CREB1 fusion transcript that was shown by reverse transcription-PCR. In two of the cases tested, EWS gene rearrangement was also confirmed by fluorescence in situ hybridization and the EWS-CREB1 genomic junction fragments were isolated by long-range dna PCR. RESULTS: Morphologically, all three tumors lacked melanin pigmentation. By immunohistochemistry, there was a strong and diffuse S100 protein reactivity, whereas all melanocytic markers were negative. Ultrastructurally, two of the cases lacked melanosomes. The melanocyte-specific transcript of MITF was absent in two cases, and only weakly expressed in the third case. The Affymetrix gene expression data available in one case showed lower expression of the melanocytic genes MITF, TYR, and TYRP1, compared with four EWS-ATF1-positive CCSs of non-gastrointestinal origin. CONCLUSIONS: EWS-CREB1 may define a novel subset of CCS that occurs preferentially in the gastrointestinal tract and shows little or no melanocytic differentiation. Thus, evidence of melanocytic lineage or differentiation is not a necessary feature of sarcomas with gene fusions involving CREB family members.- - - - - - - - - - ranking = 0.5keywords = hybridization (Clic here for more details about this article) |
6/6. Malignant melanoma of the soft parts (clear-cell sarcoma): confirmation of EWS and ATF-1 gene fusion caused by a t(12;22) translocation.We report on the cytogenetic and molecular analysis of a malignant melanoma of the soft parts (MMSP). A t(12;22)(q13;q12) was found as the only structural chromosomal change, and this provides additional support for the important role of this translocation in MMSP development. Molecular analysis revealed in frame fusion between exon 10 of the Ewing's sarcoma oncogene (EWS) and codon 110 of ATF-1. In previously analyzed MMSPs, junctions were observed between EWS exon 8 and ATF-1 codon 65. The present data thus indicate that, as in Ewing's sarcoma, different fusion proteins can occur in MMSP. The presence of the EWS/ATF-1 fusion gene in the tumor cells was demonstrated by dual color fluorescence in situ hybridization on interphase nuclei. Our data provide additional support for the specific association of the t(12;22) and the resulting EWS/ATF-1 gene fusion in MMSP. This particular genetic aberration, therefore, serves as a strong diagnostic marker for MMSP. We conclude that detection of the t(12;22) by cytogenetic or molecular analysis is useful in establishing or confirming the diagnosis of MMSP.- - - - - - - - - - ranking = 0.5keywords = hybridization (Clic here for more details about this article) |