1/10. Analysis of chromosome 22q as an aid to the diagnosis of rhabdoid tumor: a case report.Malignant rhabdoid tumor is a highly aggressive tumor of childhood that may present as a soft-tissue primary tumor. We report a soft-tissue neoplasm that was polyphenotypic by immunohistochemical expression of epithelial, mesenchymal, and neural markers and did not meet the criteria for any of the usual pediatric small round-cell tumors. The findings raised the diagnosis of rhabdoid tumor, leading to testing for WT1 mRNA and protein expression, which were positive, as has been reported for renal rhabdoid tumor. This tumor had the typical clinical behavior of rhabdoid tumor with therapy resistance and early tumor-related death. Multicolor spectral karyotyping of this neoplasm showed a balanced translocation between chromosomes 1 and 22 with breakpoints at 1p36 and 22q11-12. The latter region is commonly involved in rhabdoid tumor. This change was also identified by fluorescence in situ hybridization. This case suggests that studies of chromosome 22 may be required to distinguish rhabdoid tumor from other soft-tissue tumors.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/10. Spinal atypical teratoid/rhabdoid tumor in an infant.Atypical teratoid/rhabdoid tumor of the central nervous system in infancy and childhood was established as an entity based on histological, immunohistochemical, and cytogenetic studies. We report the case of a 7-month-old girl who presented with progressive paraplegia and hypesthesia of her legs. Imaging studies revealed a spinal cord mass occupying the entire spinal canal below the T(7) level. Through a T(12)-L(3) laminectomy, the intramedullary tumor was partially debulked. Histologically, the tumor specimen had rhabdoid cells, and immunostaining showed vimentin and cytokeratin positivity. No abnormality of chromosome 22q was detected with the fluorescence in situ hybridization method.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
3/10. Rhabdoid tumour of the lung is a dedifferentiated phenotype of pulmonary adenocarcinoma.AIMS: Primary rhabdoid tumour of the lung is rare, and histological and biological characteristics have not been fully documented. We describe three cases of primary lung rhabdoid tumour, all associated with adenocarcinoma, and investigate the histological features and biological characteristics. methods AND RESULTS: Three cases were obtained from a total 902 cases of surgically removed primary lung tumours between 1986 and 1998. The rhabdoid cells were found to occupy about 50-90% of each tumour. All of the tumours had nonrhabdoid adenocarcinoma foci in the centre of the tumours. Transition between the adenocarcinomatous and rhabdoid components was demonstrated. Detailed immunohistochemical studies were carried out. The epithelial markers, cytokeratins and epithelial membrane antigen (EMA), were strongly expressed in rhabdoid and adenocarcinomatous components. Furthermore, surfactant apoprotein A was positive in both components in one case, but myoglobin, MyoD and HHF35 were not expressed. vimentin was strongly and diffusely stained in all cases. The neuroendocrine markers, chromogranin a (all cases), neuron-specific antigen (NSE) (two cases) and CD56 (one case) were occasionally positive in only a small number of the rhabdoid tumour cells. GM-CSF was positively stained in one case, and the dedifferentiated characteristics of the rhabdoid cells was suggested. Proliferative cell nuclear antigen (PCNA) was strongly demonstrated in the rhabdoid tumour cells (all cases). To gain better understanding the highly proliferative characteristics of the tumours, p53 gene (exons 5-8) mutation was examined by DNA sequencing analysis; mutation of the p53 DNA was not detected. Overexpression of p53 protein was also not demonstrated in all cases. HPV6 was demonstrated in one case by PCR method and also non-isotopic in-situ hybridization (NISH). Two cases died in a short period of time (3 years and 4 months, respectively). CONCLUSION: The rhabdoid cells in these three cases were considered to represent the dedifferentiated components of the accompanying adenocarcinoma. Dedifferentiated characteristics (neuroendocrine markers, GM-CSF, vimentin, and the aggressive behaviour) were evident.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
4/10. Aggressive uterine sarcoma with rhabdoid features: diagnosis by peritoneal fluid cytology and absence of INI1 gene mutation.We report a primary uterine sarcoma with classic histologic, immunohistochemical, and ultrastructural features of a malignant extrarenal rhabdoid tumor (MERT). It arose in a 71-year-old woman who presented with postmenopausal bleeding, ascites, and a right pelvic mass. Malignant cells with rhabdoid morphology were identified by cytologic examination of the peritoneal fluid. Exploratory laparotomy revealed a 10-cm right adnexal mass and disseminated peritoneal tumor. Pathologic study showed diffuse expansion of the endometrial stroma by rhabdoid-like cells with transmural infiltration of the myometrium and extensive involvement of uterine serosa and right ovary by tumor. Neoplastic cells were immunoreactive for vimentin, cytokeratin, and epithelial membrane antigen, and cytoplasmic whorls of intermediate filaments were observed by electron microscopy. fluorescence in situ hybridization (FISH) studies with chromosome 22-specific probes showed no loss of the INI1 gene, and no coding sequence mutation was identified.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
5/10. Malignant rhabdoid meningioma arising in the setting of preexisting ganglioglioma: a diagnosis supported by fluorescence in situ hybridization. Case report.A highly malignant brain neoplasm with rhabdoid morphological features emerged in the bed of a subtotally resected ganglioglioma in a 54-year-old retired nuclear submarine officer. A combined application of neuroimaging, immunohistochemical studies, electron microscopy, and fluorescence in situ hybridization (FISH) was used to establish the morphological identity of the tumor. The rhabdoid appearance of the tumor cells indicated either an especially malignant variant of rhabdoid meningioma or an atypical teratoid/rhabdoid tumor with an unusually late onset. Whereas immunohistochemical studies and electron microscopy could only be used to narrow down the differential diagnosis, FISH revealed loss of one copy of NF2 with preservation of the INI1 region on 22q, thus establishing the identity of the tumor.- - - - - - - - - - ranking = 5keywords = hybridization (Clic here for more details about this article) |
6/10. comparative genomic hybridization and pathological findings in atypical teratoid/rhabdoid tumour of the central nervous system.The atypical teratoid/rhabdoid tumour (AT/RT) is an uncommon tumour of the central nervous system in children, characterized by the presence of a rhabdoid cell component associated with variable combinations of primitive neuroectodermal tumour, mesenchymal and epithelial differentiation. immunohistochemistry reveals a complex pattern of antigen expression and cytogenetic studies have demonstrated losses from chromosome 22. We have performed comparative genomic hybridization (CGH) on paraffin-embedded material from three cases of AT/RT. Two cases showed losses from chromosome 22 associated with other chromosome imbalances including losses from 1p in both cases. The third case demonstrated a loss from 8p as the sole abnormality. While monosomy or deletion from chromosome 22 is a useful diagnostic marker for AT/RT, it is not present in all cases. The variation in cytogenetic patterns reported for this tumour type raises the possibility that different genetic pathways may underlie this tumour phenotype and warrants the further definition of the cytogenetic spectrum for this rare tumour.- - - - - - - - - - ranking = 5keywords = hybridization (Clic here for more details about this article) |
7/10. Molecular genetic alterations and gene expression profile of a malignant rhabdoid tumor of the kidney.Malignant rhabdoid tumor of the kidney (MRTK) is a rare but highly aggressive tumor in children, and knowledge about the molecular signature of this tumor is limited. We report the molecular genetic alterations and gene expression profile of an MRTK tumor that arose in a 4-month-old Japanese girl. fluorescence in situ hybridization and Southern blot analyses revealed a homozygous deletion of an approximately 0.29-Mb genomic region bordered by the Rgr and ddt genes in these tumor cells. This deleted region encodes SMARCB1, a candidate tumor suppressor gene for MRTK. Using a high-density oligonucleotide DNA array, we found increased expression of 25 genes, including genes involved in the cell cycle (10 genes), dna replication (3 genes), cell growth (5 genes), and cell proliferation (5 genes), in this MRTK tumor sample, compared with a noncancerous kidney (NK) sample. On the other hand, 64 genes, including 4 genes regulating apoptosis, were found to show decreased expression in this MRTK tumor sample, compared with the NK sample. Among these alterations, we found alterations of expression of some genes, such as IGF2, MDK, TP53, and TNFSF10, in this MRTK tumor, as described previously. The molecular genetic alterations and altered pattern of gene expression found in this case may have contributed to the biological characteristics of the MRTK tumor that arose in our patient.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
8/10. Malignant rhabdoid tumor of the kidney: involvement of chromosome 22.Cytogenetic and molecular studies have demonstrated that involvement of 22q is a non-random finding in malignant rhabdoid tumors (MRTs) of the brain. We present an MRT of the kidney with the karyotype 47,XY, i(1)(q10), der(8)t(8;22)(q12;q11.2),der(22)t(8;22)(q23 or q24.1;q11.2). This unbalanced reciprocal translocation was confirmed by fluorescence in situ hybridization (FISH) with chromosome-specific paints for chromosomes 8 and 22. Molecular analysis demonstrated a partial deletion of 22q in the BCR region at q11.2, strengthening the suspicion that this is a critical region for the initiation or progression of these highly malignant neoplasms. Establishing non-random cytogenetic changes in MRTs arising from the kidney may be of value in distinguishing these rare, but often fatal tumors from other renal neoplasms that mimic them histologically. The similarity in cytogenetic and molecular abnormalities between renal and extra-renal MRTs argues against the concept that extra-renal MRTs are only representative of a rhabdoid phenotype, rather than being true rhabdoid tumors.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
9/10. Malignant rhabdoid tumor of the kidney expresses insulin-like growth factor ii transcripts.insulin-like growth factor ii (IGF-II) is thought to play a major role in fetal growth and development. High levels have been demonstrated in blastemal cells of both normal fetal kidney and Wilms' Tumor (WT). In this report, 2 cases of malignant rhabdoid tumor of the kidney (MRTK) were studied to detect the expression of IGF-II mRNA by in situ hybridization using 35S labelled rna riboprobes. Results showed highly strong and specific IGF-II mRNA expression by tumor cells.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
10/10. Cytogenetic and molecular analysis of a t(1;22)(p36;q11.2) in a rhabdoid tumor with a putative homozygous deletion of chromosome 22.Malignant rhabdoid tumors are rare and aggressive neoplasms of childhood, occurring in the kidney or in various extrarenal locations. Most cytogenetic studies of these tumors have shown the frequent involvement of chromosome 22, including translocations and/or deletions, with a critical region for a rhabdoid tumor gene mapping to chromosome segment 22q11, close to BCR. We report a case of an extrarenal rhabdoid tumor with a t(1;22)(p36;q11.2) that was associated with deletions of chromosomes 1 and 22. We have performed fluorescence in situ hybridization to bracket the translocation breakpoints on both chromosomes and microsatellite analysis to establish the deletion of chromosome 22 more precisely. The chromosome 22 translocation breakpoint is localized close to BCR, in the region covered by the overlapping YACs 446B5 and 361D9, and it is associated with a proximal hemizygous deletion of approximatively 2 Mb. On chromosome 1, the translocation breakpoint maps to a 25 cM region, proximal to D1Z2 and distal to PND, and is also associated with an estimated deletion of 8 Mb. Moreover, microsatellite analysis has demonstrated a homozygous deletion of chromosome 22 for three contiguous loci, immediately distal to BCR. This result suggests that a tumor suppressor gene involved in rhabdoid tumor oncogenesis could be localized in this region of chromosome 22.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
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