1/21. neuroblastoma in two siblings supports the role of 1p36 deletion in tumor development.Familial neuroblastoma occurs rarely. We studied a family with three children; one of them has a disseminated (stage 4) and another has a localized (stage 2) neuroblastoma. We observed subtelomeric locus D1Z2 (1p36) deletion in both tumors by using double-color fluorescence in situ hybridization. The MYNC gene was found in single copy in both tumors. loss of heterozygosity (LOH) and restriction fragment length polymorphism analyses were performed by using dna from frozen tumor cells and from microdissected tumor areas excised from paraffin-embedded sections. We detected somatic LOH at locus D1S468 (1p36) in a tumor-cell population with a trisomy 1 of the stage-2 patient. neuroblastoma cells of the stage-4 patient were diploid and showed allelic loss at the following loci: D1S172, D1S80, D1S94, D1S243, D1S468, D1S214, D1S241, and D1S164. Haplotype study showed that the siblings inherited the same paternal 1p36-->pter chromosome region by homologous recombination and that, in the two tumors, arm 1p of different chromosomes of maternal origin was damaged. Our results suggest that the siblings inherited the predisposition to neuroblastoma associated with paternal 1p36 region and that tumors developed as a consequence of somatic loss of the maternal 1p36 allele.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/21. Recurrent Epstein-Barr virus-associated post-transplant lymphoproliferative disorder: report of a patient with histologically similar but clonally distinct metachronous abdominal and brain lesions.A liver transplant patient developed a single central nervous system (CNS) intraparenchymal lesion 5 months after the diagnosis of an intraabdominal diffuse large B-cell post-transplant lymphoproliferative disorder (PTLD). biopsy of the new CNS lesion showed a diffuse large B-cell PTLD morphologically and immunohistochemically indistinguishable from the abdominal lesion. In addition, both lesions were positive for Epstein-Barr virus (EBV) dna by polymerase chain reaction (PCR) and for EBV-encoded rna by in situ hybridization. Although these results were consistent with a metastatic origin for the CNS lesion, the finding of an intraparenchymal lesion without leptomeningeal or dural spread was suggestive of a new primary CNS lymphoma. Proof that the brain lesion was a second primary and not a metastasis was obtained by immunoglobulin gene rearrangement studies and assessment of EBV clonality. Multiple primary lymphoid neoplasms arise at higher frequency in the setting of immunosuppression, and molecular investigations of tumor clonality can provide clinically relevant staging and prognostic information.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
3/21. Malignant lymphoma localized in the abdomen: detection of Ig gene rearrangement from the specimen obtained by percutaneous lymph node biopsy.A 32-year-old man was admitted to our hospital because of lumbago and an abdominal mass revealed by abdominal ultrasonography. Abdominal CT scan and MRI revealed multiple para-aortic lymph node swelling involving several arteries and veins. As there was no superficial lymph node swelling, percutaneous lymph node biopsy was performed under ultrasonographic guide. Although non-Hodgkin's lymphoma, diffuse, small cell type was suspected by light microscopic study, the monoclonality of the lymphocytes in the obtained specimen was not clear by the immunohistochemical study. Southern blot hybridization analysis of the biopsy specimen revealed the rearrangement of IgH and IgL (lambda) chain gene, indicating the existence of monoclonal proliferation of lymphoma cells. The dna analysis appears useful for the differential diagnosis of lympho-proliferative diseases.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
4/21. Evolution of unbalanced gain of distal chromosome 2p in neuroblastoma.neuroblastoma, one of the most common tumors of childhood, presents at diagnosis with a vast number of recurrent chromosomal imbalances that include hyperdiploidy for whole chromosomes, partial loss of 1p, 3p, 4p, 11q, 14q, partial gain of 1q, 7q, 17q and amplification of MYCN. These abnormalities are nonrandomly distributed in neuroblastoma as loss of 3p and 11q rarely occur in MYCN amplified neuroblastomas. Here, we report on a patient who had a non-MYCN amplified 3p-/11q- neuroblastoma at diagnosis who subsequently developed a high level of MYCN amplification in bone marrow metastases 41 months after induction of complete remission. The tumor at diagnosis had low level unbalanced gain of distal 2p. In order to assess the frequency of low level gain of distal 2p in neuroblastoma, we examined the comparative genomic hybridization results from 60 neuroblastomas. Among non-MYCN amplified neuroblastomas, 8/45 (18%) had low level gain of distal 2p. Low level gain for a segment of 2p (i.e. a region larger than the 2p23-->p24 undergoing amplification) was also detected in five of the 15 tumors that had high level MYCN amplification. The possibility that low level gain of distal 2p is a risk factor for high level MYCN amplification is discussed.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
5/21. Ewing sarcoma/peripheral primitive neuroectodermal tumor: adult abdominal tumors with an Ewing sarcoma gene rearrangement demonstrated by fluorescence in situ hybridization in paraffin sections.The differential diagnosis of small round cell tumors is exhaustive and requires ancillary studies. Relatively recently, fluorescence in situ hybridization (FISH) using probes for specific gene rearrangements has gained wide acceptance. This technique is particularly useful in the differential diagnosis of Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET) and desmoplastic small round-cell tumor (DSRCT). In ES/PNET, the EWS gene is juxtaposed to the FLI-1 gene in 85% of cases and to the ERG gene in another 7% of cases; the EWS gene is juxtaposed to the WTI gene in DSRCT. documentation of the EWS gene rearrangements in EWS/PNET has previously been demonstrated in frozen tissue. We report 2 unusual cases of EWS/PNET diagnosed in abdominal tumors in adults. Although the immunohistochemical results supported a diagnosis of ES/PNET, 1 case morphologically resembled DSRCT. The diagnosis in these 2 cases was confirmed by the FISH demonstration of EWS/FLI-1 gene fusion in paraffin-embedded tissue. Thus, the usefulness of FISH demonstration of an EWS gene rearrangement with these specific probes in such unusual cases is supported and is demonstrated in paraffin-embedded tissue.- - - - - - - - - - ranking = 5keywords = hybridization (Clic here for more details about this article) |
6/21. Intra-abdominal desmoid tumor following retroperitoneal lymph node dissection for testicular germ cell tumor.In the testicular cancer post-treatment setting a rapidly growing retroperitoneal mass leads to a differential diagnosis including recurrent germ cell tumor, residual mature teratoma, or sarcomatoid degeneration. We report the case of a 27-year-old man with a large abdominal mass occurring in the setting of a mixed germ cell tumor after radical orchiectomy with primary chemotherapy followed by retroperitoneal lymph node dissection. Surgical excision of this mass followed by pathological review revealed an intra-abdominal desmoid tumor. fluorescence in situ hybridization (FISH) for isochromosome 12p failed to demonstrate a germ cell tumor origin. This is the fourth such case of an intra-abdominal desmoid tumor after retroperitoneal lymph node dissection for testicular cancer in the urologic literature. This case highlights the need for careful consideration of a desmoid tumor when a rapidly growing spindle cell tumor is encountered in a post-treatment testis cancer patient.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
7/21. Chromosomal localization of amplified N-myc in neuroblastoma cells using a biotinylated probe.G-banded chromosome analysis of neuroblastoma cells from two children revealed homogeneously staining regions (hsr) in one patient and double minutes (dmin) in the other. Subsequently, both abnormalities were confirmed as areas of N-myc amplification using chromosomal in situ hybridization with a biotinylated N-myc probe. In addition, the first patient's karyotype contained a possible derivative chromosome 17, which was also demonstrated to contain amplified N-myc, indicating the presence of an hsr unidentified by G-banding. Intercellular heterogeneity in the degree of amplification was also identified in the nuclei of interphase cells. This technique provides a quick method for detecting gene amplification, the identification of which may have useful clinical implications.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
8/21. Cytogenetic and molecular characterization of a newly established neuroblastoma cell line LS.A new human neuroblastoma cell line (LS) that originated from an abdominal tumor of a 16-month-old girl is presented; it was classified, according to Evans, as being stage III. Morphological (dense-core particles) and biochemical characteristics (dopamine-beta-hydroxylase, acetylcholinesterase, neuron-specific-enolase) confirmed the diagnosis. In addition to a slightly variable modal chromosome number of 48 or 49 (because of marker-chromosomes and autosomal trisomies), cytogenetic analysis revealed two constantly appearing chromosomes with homogeneously stained regions (HSR's). The karyotype remained constant over 50 passages in vitro [49,XX, -12, der5, 17, mar1, mar2]. Double minutes were a rare phenomenon and appeared only in a few metaphases. in situ hybridization showed that some of the HSR's consisted of amplified N-myc copies. The distribution of the N-myc copies according to in situ hybridization signals along the HSR's was compared with the data of Southern and Northern blotting analyses.- - - - - - - - - - ranking = 2keywords = hybridization (Clic here for more details about this article) |
9/21. Demonstration of Epstein-Barr virus in immunoblastic sarcoma of B-cells arising in a child with primary immunodeficiency disease.The subject of this investigation was an 11-month-old infant girl who presented with a pathological fracture of the right femur due to a metastasis from an abdominal immunoblastic sarcoma. Her past history included recurrent, intractable bacterial and fungal infections. Investigations of her immune status revealed low numbers of t-lymphocytes, a reversed T-helper (TH)/T-suppressor (TS) cell ratio, no response of her peripheral blood lymphocytes to pokeweed mitogen, phytohemagglutinin, concanavalin a, and candida albicans, and an inability of her cells to react in a mixed lymphocyte culture. serum levels of IgG, IgM, and IgA were all below normal. No thymic shadow was visible on the chest radiograph. There was no evidence of adenosine deaminase or nucleoside phosphorylase deficiencies. The tumor cells exhibited both surface IgM and IgG, and many of the cells contained large amounts of cytoplasmic IgM. light chain specificity was restricted to lambda chain for both surface and cytoplasmic immunoglobulin. Ultrastructural study of the tumor cells revealed the presence of both intranuclear and cytoplasmic virions in roughly 1% of the tumor cells. These viral particles strongly resembled herpes viruses. dna-hybridization studies on the neoplasm revealed the presence of 7-10 genome equivalents of Epstein-Barr virus-dna per tumor cell.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
10/21. Erythrocytosis complicated by multiple paraganglioma.We report the case of a 22-year-old woman with onset of erythrocytosis at the age of 9 years. Endocrinological and radiological examinations revealed an elevated catecholamine level and the presence of multiple abdominal tumors. After the removal of the tumors, the catecholamine level normalized, whereas erythropoietin remained at the same level and erythrocytosis persisted. The tumor lysate contained considerable amounts of catecholamine but not erythropoietin. Moreover, no erythropoietin mRNA was detected in the tumor by in situ hybridization. These data suggest that this paraganglioma did not produce erythropoietin. A review of the literature showed the existence of patients with early-onset erythrocytosis complicated with paraganglioma, whose erythrocytosis was not relieved even after the resection of paraganglioma.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
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