1/7. ring chromosomes in a malignant mesenchymoma.We report, for the first time, the cytogenetic and molecular genetic constitution of a human mesenchymoma. As in several other soft tissue sarcomas, supernumerary ring and rod-shaped marker chromosomes were observed next to an otherwise normal diploid karyotype. Comparative genomic in situ hybridization and whole chromosome painting experiments revealed that chromosome 1q21-q25 and 12q14-q15 sequences were amplified, and that these sequences resided on the supernumerary marker chromosomes. We assume that, in this malignant mesenchymoma, the observed chromosomal anomalies may be associated with its well differentiated liposarcomatous component.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/7. Translocation of the HMGI-C ( HMGA2) gene in a benign mesenchymoma (chondrolipoangioma).Mesenchymomas are neoplasms in which there are at least two types of differentiated cells of mesenchymal derivation other than fibrous tissue. Chondrolipoangioma is a rare type of mesenchymoma composed predominantly of cartilage and adipose tissue with vascular elements and myxoid tissue present in lesser proportions. cytogenetic analysis was performed on a case of chondrolipoangioma and revealed a t(12;15) (q13;q26) as the sole chromosome abnormality in 40 metaphases analyzed. However, using fluorescence in situ hybridization (FISH) analysis, a complex rearrangement was found involving chromosomes 2, 12, and 15, with a cryptic rearrangement of the gene ( HMGI-C; HMGA2) coding for high-mobility group I protein. This finding suggests a role for the HMGI-C gene also in the pathogenesis of this uncommon benign tumor type, in addition to its well-established role in the pathogenesis of common benign tumors such as lipomas, uterine leiomyomas, pulmonary chondroid hamartomas, and endometrial polyps.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
3/7. Infiltrating intramuscular lipoma of the temporal muscle. A case report with molecular cytogenetic analysis.Intramuscular lipomas are uncommon benign mesenchymal tumors which infiltrate skeletal muscle and are exceedingly rare in the head and neck region. Because of the infiltrating nature of the lesion and a high propensity for recurrence, they are sometimes difficult to distinguish from well-differentiated liposarcomas (WDLS). We report, the first case of an infiltrating lipoma of the temporal muscle in a 62-year-old white man who presented with a slow growing mass in the left temporal region. The histopathological examination showed diffuse infiltration of the striated muscle fibers by mature adipocytes. There were no lipoblasts or cells with atypical nuclei as described in WDLS. We performed interphase fluorescence in situ hybridization (FISH) analyses using painting probes for chromosome 12 and a specific probe for the MDM2 gene and comparative genomic hybridization. The results did not identify MDM2 or 12q amplification and therefore confirmed the benign nature of the lesion.- - - - - - - - - - ranking = 2keywords = hybridization (Clic here for more details about this article) |
4/7. 11q13 alterations in two cases of hibernoma: large heterozygous deletions and rearrangement breakpoints near GARP in 11q13.5.Hibernomas are rare, benign tumors with a histological appearance resembling that of brown adipose tissue. The diagnosis of hibernomas may be difficult because some of them contain only a small number of the characteristic multivacuolated fat cells and can be mistakenly classified as well-differentiated liposarcomas. Cytogenetic information has been reported for 10 cases, showing that these tumors are characterized by structural rearrangements involving 11q13. Previous fluorescence in situ hybridization (FISH) studies revealed consistent and sometimes cryptic losses of the MEN1 region in 11q13.1. Here, we describe the molecular cytogenetic analysis of two new hibernoma cases. Both tumors showed complex rearrangements, simultaneously including translocations, inversions, and deletions affecting the pair of chromosomes 11. The translocation partners were chromosome 5 in one case and chromosomes 16 and 22 in the other case. The 11q13 region was concomitantly rearranged on both chromosomes 11. FISH studies revealed large heterozygous deletions within the 11q13 band, from 11q13.1 to 11q13.5. genes such as PYGM, MEN1, CCND1, FGF3, ARIX, and GARP were deleted, showing that the size of the 11q13 altered region was larger than previously reported. Furthermore, both tumors had breakpoints in 11q13.5, one of them in the immediate proximity of the GARP gene. Our results suggest that rearrangements of GARP or a neighboring gene may be important for the pathogenesis of hibernomas.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
5/7. A novel site of dna amplification on chromosome 1p32-33 in a rhabdomyosarcoma revealed by comparative genomic hybridization.cytogenetic analysis of a human embryonal rhabdomyosarcoma revealed a near-diploid karyotype with structural chromosome aberrations not involving the typical rearrangements of rhabdomyosarcomas, plus a large number of double minutes. comparative genomic hybridization revealed a previously undescribed site of dna amplification on the short arm of chromosome 1 (band 1p32-33).- - - - - - - - - - ranking = 5keywords = hybridization (Clic here for more details about this article) |
6/7. Complex translocation [7;22] identified in an epithelioid hemangioendothelioma.We describe a malignant epithelioid hemangioendothelioma arising in the back of a 45-year-old man with pulmonary and bone marrow metastases. light microscopic and immunohistochemical features of this tumor are presented. karyotyping revealed several clonal abnormalities: a complex unbalanced translocation [7;22] involving multiple breakpoints (confirmed by fluorescence in situ hybridization), a Robertsonian t(14;14), and loss of the y chromosome. monosomy for chromosome 11 was noted in a subset of the tumor cells. To our knowledge a karyotype has not been previously reported for this unusual vascular tumor.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
7/7. Epstein-Barr virus-associated renal smooth muscle neoplasm: report of a case with review of the literature.Epstein-Barr virus (EBV) has been associated with nasopharyngeal carcinoma, some Burkitt's-type lymphomas, and posttransplantation lymphoproliferative disorder. Recently, an association between EBV and smooth muscle tumors, both malignant and benign, in the acquired immunodeficiency syndrome and posttransplantation populations has been made. We report, to our knowledge, the first case of a renal EBV-associated smooth muscle tumor. A 33-year-old man with acquired immunodeficiency syndrome presented with a mass of the left kidney that was radiographically suspicious for malignancy. He underwent left radical nephrectomy. The tumor measured 3.0 cm in the largest dimension, was well-circumscribed, and was composed of fascicles of bland spindle cells with blunt-ended nuclei, which often intersected at right angles. Focal areas of cell crowding and nuclear pleomorphism were present. No areas of lipomatous differentiation were identified. Immunohistochemically, the tumor cells were positive for desmin and muscle-specific actin and were negative for HMB-45 and CD21 (an EBV receptor). in situ hybridization with EBV-encoded rna-1, a probe that recognizes a non-poly(A) rna EBV transcript expressed in latently infected cells, was diffusely positive. At 6 months postnephrectomy, the patient showed no evidence of local recurrence or metastases. The incidence of this tumor is expected to increase as both the numbers of patients undergoing solid organ transplantation and the survival time of patients with the acquired immunodeficiency syndrome increase. A better understanding of the biology and pathogenesis of this entity will be important for future management of these patients.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |