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PubMed2001

Imaging-guided core biopsy for the diagnosis of malignant tumors in pediatric patients.

OBJECTIVE: We evaluated the ability of imaging-guided core biopsy to obtain sufficient tissue from pediatric tumors for a definitive diagnosis of malignancy on which treatment could be based. MATERIALS AND METHODS: Thirty-four biopsies (biopsies of the abdomen, 32; of the chest, 2) were performed on 34 children at presentation under CT or sonographic guidance using 14-, 18-, or both 14- and 18-gauge needles. A minimum of two tissue cores was obtained. Most biopsies were performed under general anesthesia, permitting other procedures to be performed. The biopsy results were confirmed by subsequent surgical pathology, bone marrow biopsy, biochemical or clinical features, and follow-up examination. RESULTS: The needle biopsy diagnoses were nephroblastoma (n = 11), neuroblastoma (n = 7), renal cell carcinoma (n = 2), synovial sarcoma (n = 1), non-Hodgkin's lymphoma (n = 2), clear cell sarcoma (n = 1), rhabdoid tumor (n = 1), pulmonary blastoma (n = 2), embryonal rhabdomyosarcoma (n 1), germ cell tumor (n = 1), adrenal carcinoma (n = 1), inflammatory tissue (n = 2), desmoplastic tumor of the mesentery (n = 1), and primitive neuroectodermal tumor (n = 1). In 28 patients, the results were confirmed as correct (22 with surgery and 6 with follow-up examination). Four patients required additional biopsy. In two of these patients, the core biopsy showed inflammatory tissue only, and an open biopsy of a different site was performed; the other two patients did not respond to therapy on the basis of needle biopsy results, and an open biopsy altered the diagnosis. Two patients with widespread disease were excluded because they did not respond to treatment and were too ill to undergo an open biopsy. Only one significant complication was recorded. CONCLUSION: Imaging-guided core biopsy is a safe and reliable means of obtaining sufficient tissue to make a confident histologic diagnosis of malignant pediatric tumors in a high percentage of patients.

Abdominal Neoplasms↗
PubMedDate not supplied

Comparison of effects of doxorubicin and radiation on p53-dependent apoptosis in vivo.

The effects of doxorubicin and radiation on apoptosis, p53 expression, and tumor growth in human tumor xenografts were investigated. Human ependymoblastoma (NNE), primitive neuroectodermal tumor (YKP), glioblastoma (KYG) and small cell lung carcinoma (GLS) that are all transplantable to nude mice were treated with doxorubicin (8 mg/kg) or radiation (1 Gy). The histological study was performed by using TUNEL and p53 staining. Cytotoxic effects of doxorubicin and radiation were compared with no-treatment group by the growth curves and apoptotic index of tumor to each treatment. In NNE with wild-type p53, doxorubicin induced growth delay of tumors (tumor volume doubling time; 13.7+/-3.3 days in control group vs 30.4+/-1.5 days in doxorubicin group), but no growth delay of tumors in KYG and GLS with mutant type p53. While radiation-induced apoptosis appeared most frequently at 6 h after irradiation, doxorubicin-induced apoptosis had a tendency to appear later. Furthermore, although the frequency of doxorubicin-induced apoptosis was lower than that of apoptosis by 1 Gy irradiation, apoptotic cells appeared for many hours after the treatment. Doxorubicin-induced apoptosis may be correlated with p53 phenotype because apoptosis was induced only in tumor with wild-type p53, but it appeared less frequently and later than radiation-induced apoptosis.

Animals↗
PubMed1992

[Synaptophysin in the nervous system and endocrine cells].

Synaptophysin is a major integral membrane glycoprotein of neuronal synaptic vesicles that is present in virtually all synapses and shows a high degree of evolutionary conservation in mammalian species. It has also been detected in numerous endocrine cell types where it is localized in the membrane of small synaptic-like vesicles which are thought to constitute a previously unknown secretory pathway. Antibodies directed against synaptophysin are a valuable tool for the immunohistochemical quantitation of synapses. Moreover, synaptophysin is a most reliable and specific marker molecule for normal and neoplastic neuroendocrine cells. In the nervous system, synaptophysin-positive tumors comprise ganglioneuromas, ganglioneuroblastomas, neuroblastomas, paragangliomas and primitive neuroectodermal tumors.

Animals↗
PubMed1990

Acridine orange--RNA histofluorescence of sarcomas and small round cell tumors of childhood.

Forty-nine pediatric malignant neoplasms were stained with acridine orange (AO) fluorochrome to qualitatively evaluate cytoplasmic RNA content. The application of AO as a supplementary stain in surgical pathologic diagnosis is based on the premise that specific neoplastic cell types characteristically and consistently contain few or many cytoplasmic ribosomes. Primitive tumors such as Ewing's sarcoma and primitive neuroectodermal tumors showed negative or low-intensity AO-RNA cytoplasmic staining. Differentiated sarcomas such as rhabdomyosarcomas and lymphomas exhibited moderate to strong AO-RNA cytoplasmic fluorescence. Acridine orange--RNA staining provides an easy, convenient, and inexpensive adjunct in the histopathologic differential diagnosis of sarcomas. It is particularly useful for distinguishing Ewing's sarcomas from other small round cell sarcomas of childhood.

Acridine Orange↗
PubMed1981

Ultrastructure of pineal parenchymal neoplasms.

The fine structures of two pineal parenchymal neoplasms has been described. The tumors contained a predominance of small, poorly differentiated cells with prominent nuclei and scanty cytoplasm. These cells were similar to those found in medulloblastomas, primitive cerebral neuroectodermal tumors, and fetal cerebellum and cerebrum. Some cells contained 9 + 0 cilia, dense core vesicles, and processes containing microtubules and numerous dense core and clear vesicles, suggesting neuronal differentiation. Astrocytic elements were also present. This study suggests that the predominant cells of these tumors are primitive neuroectodermal elements which have the potential to differentiate along several different lines.

Adult↗
PubMed1991

Immunohistochemical analysis of neural cell adhesion molecules. Differential expression in small round cell tumors of childhood and adolescence.

The neural cell adhesion molecule (NCAM) was discovered in a search for cell surface antigens of chicken neurons that contribute to cell adhesion and pattern formation during development. Homologous adhesion molecules have been identified in several species, including humans. In this immunohistochemical study, the authors examine the role of human NCAM in tumor diagnosis. The authors used a monoclonal antibody (MAb), 5.1H11, to examine NCAM immunoreactivity in frozen sections of more than 450 tumors, including more than 80 small round cell tumors (SRCT) of childhood and adolescence (neuroblastomas, Ewing's sarcomas [ES], peripheral neuroepitheliomas [PN], primitive neuroectodermal tumors [PNET], esthesioneuroblastomas, malignant ectomesenchymoma, medulloblastomas, small cell osteosarcomas, mesenchymal chondrosarcomas, embryonal rhabdomyosarcomas, and lymphomas). The authors show that 1) neuroblastomas and primary brain tumors are NCAM+; 2) ES, most PN/PNETs, and melanomas are NCAM-; 3) embryonal rhabdomyosarcomas and various other sarcomas are NCAM+; 4) neuroendocrine tumors are NCAM+; 5) subsets of carcinomas of kidney, ovary, lung and other organs are NCAM+; and 6) lymphoid tumors are NCAM-. Tests with normal fetal and adult tissues indicate that these findings reflect only in part the NCAM phenotypes of corresponding normal tissues. Notably the NCAM- phenotype of ES and PN/PNET is not explained by current histogenetic models for these tumors, which suggest a primitive neuroectodermal origin. Finally the authors show that NCAM expression among SRCT has an inverse relationship with the expression of p30/32MIC2, a cell surface antigen of ES and PN/PNET detected with MAb HBA71. These results suggest that immunohistochemical assays for NCAM and p30/32MIC2 expression may aid in the further characterization of SRCT of childhood and adolescence.

Antibodies, Monoclonal↗
PubMed1988

Ependymal and choroid plexus tumors. Cytokeratin and GFAP expression.

Twenty-six ependymal and 15 choroid plexus tumors were examined with monoclonal antibody against cytokeratin using the avidin-biotin-peroxidase complex (ABC) technique. Serial sections were examined with antisera to glial fibrillary acidic protein (GFAP). In five ependymal tumors (one ependymoma, two papillary ependymomas, and two primitive neuroectodermal tumors [PNET] with ependymal cells), a variable number of cytokeratin-positive cells were present. Most tumor cells (except two PNET) were positive with GFAP antisera. Many cytokeratin-positive cells were present in all choroid plexus tumors. GFAP-positive cells were present focally in six of 11 papillomas and in one of four carcinomas. Although their staining patterns and distribution were clearly different, focal coexistence of cytokeratin and GFAP was observed in six papillomas and two ependymal tumors. Thus, some ependymal tumors (especially papillary ependymomas and occasional PNET) and many choroid plexus tumors have demonstrable positivity with antibody to cytokeratin, suggesting a transitional cell type with features of both ependyma and choroid plexus.

Carcinoma↗
PubMed2002

Predictive value of clinical evaluation in the follow-up of children with a brain tumor.

BACKGROUND: During follow-up of children with a brain tumor, traditionally surveillance-imaging studies are done in addition to clinical evaluations. The purpose of this study was to determine the role of clinical evaluations by a multidisciplinary team for the detection of recurrent tumor. PROCEDURE: We retrospectively assessed the predictive value of clinical evaluation, using subsequent neuroimaging as the gold standard. Ninety-eight children with a newly diagnosed primary brain tumor were included in the study. In these patients, 393 imaging studies were done, 75 because of clinical suspicion of recurrence, and 318 for routine surveillance only. RESULTS: In 28 of these 75 imaging studies on clinical indications, a radiologic diagnosis of recurrence was made. Only 9 out of 318 routine surveillance imaging studies resulted in an unexpected diagnosis of recurrence. Thus, the overall positive predictive value of clinical evaluation was 37%; the overall negative predictive value was 97%. The negative predictive values for specific brain tumors varied from 91% (optical glioma) to 99% (primitive neuroectodermal tumors). CONCLUSIONS: An accurate multidisciplinary clinical evaluation has a very high negative predictive value. Consequently, the added value of surveillance imaging studies is limited. The role of such studies during the follow-up of children with brain tumors should be reconsidered.

Brain Neoplasms↗
PubMed1989

Ewing's-sarcoma-associated HBA-71 tumor antigen represents a new differentiation marker of human thymocytes.

The monoclonal HBA-71 antibody recognizes a new human tumor-associated antigen of Ewing's sarcoma and peripheral neuroectodermal tumors, which is also expressed in some normal tissues, including thymus, islets of Langerhans, ependyme, adenohypophysis, Sertoli/Leydig and granulosa cells. Besides a tumor-specific reciprocal chromosomal translocation t (11:22), the expression of the HBA-71 antigen is the only marker which can be used for reliable differential diagnosis of these rare malignancies of childhood and adolescence among other small round cell tumors. The HBA-71 antigen is further characterized here by ultrastructural, functional and cell-matrix interaction studies. In immunohistochemical staining the HBA-71 reacted with the cell surface of human cortical thymocytes. The HBA-71 antigen was also found to be localized at the cell-surface glycocalyx of tumor cells using immunogold staining and electron microscopy. A panel of additional monoclonal antibodies with reactivity patterns similar to those of the HBA-71 antibody was obtained by immunization of mice with ES cell lines and boostering with thymocytes. The HBA-71 antibody triggers proliferation of thymocytes and to a lesser extent also stimulates peripheral mononuclear blood cells. Antibody-induced thymocyte cultures exhibit the phenotype of immature, CD3low thymocytes with uniform and stable expression of the HBA-71 antigen. In contrast to the thymocytes the HBA-71 antibody has an inhibitory effect on the continuous growth of the HBA-71+ tumor cell lines. The HBA-71 antigen may be involved in the regulation of growth of the positive normal and malignant tissues. Positive modulation of the antigen expression was induced in Ewing's sarcoma cell lines in response to insulin, insulin-like growth factor I (IGF-I) and by interaction of the cells with the extracellular matrix.

Animals↗
PubMed2002

[Musculoskeletal lymphomas].

Primary lymphomas of bone or skeletal muscle are rare entities. The most frequent among these diseases are primary non-Hodgkin's lymphomas of bone. They account for 3-5% of all bone tumors and 5% of all primary extranodal non-Hodgkin's lymphomas. Primary manifestations of Hodgkin's disease in bone or skeletal muscle are rarities. Primary non-Hodgkin's lymphomas of skeletal muscle are rarities as well. Primary non-Hodgkin's lymphomas of bone can be found in any patient age. A preference exists for the 3.-6. decade of life. The radiographic appearance of these entities resembles other aggressive bone tumors. Their differential diagnosis includes -- depending on the patient's age -- Ewing's sarcoma,malignant fibrous histiocytoma,metastases of small cell tumors and osteomyelitis.Further differential diagnoses are the peripheral primitive neuroectodermal tumor (PNET), osteosarcoma, eosinophilic granuloma and fibrosarcoma. Treatment of primary non-Hodgkin's lymphomas uses combinations of chemotherapy and radiation therapy. Operative treatment is reserved for the treatment of complications. The prognosis of primary non-Hodgkin's lymphomas is reflected by 10-year-survival-rates without recurrence of more than 80% in unifocal manifestations.

Bone Neoplasms↗
PubMed1998

Rare occurrence of inactivating p53 gene mutations in primary non-astrocytic tumors of the central nervous system: reappraisal by yeast functional assay.

While it is established that p53 mutation plays a critical role in the carcinogenesis of astrocytic brain tumors, its role remains to be clarified for other types of tumors in the central nervous system (CNS). Using a yeast-based assay which tests the ability of human p53 to activate transcription, we analyzed p53 mutations in 85 non-astrocytic CNS tumors, including 4 benign neuronal tumors (3 central neurocytomas and 1 pineocytoma), 12 primitive neuroectodermal tumors, 14 germ cell tumors (7 germinomas, 7 non-germinomatous tumors), 4 craniopharyngiomas, 14 ependymomas, 22 schwannomas, 10 primary brain lymphomas in immunocompetent patients, and 5 bone tumors of the skull. The only tumors found to contain p53 mutations were 3 malignant lymphomas. The presence of mutations in these cases was confirmed by DNA sequencing. Given the high accuracy and sensitivity of the yeast assay and previous negative results using conventional techniques, this indicates that p53 mutation is a rare event in non-astrocytic CNS tumor types examined here.

Adolescent↗
PubMed2005

EWS-ETS oncoproteins: the linchpins of Ewing tumors.

Ewing tumors, which comprise Ewing's sarcoma and peripheral primitive neuroectodermal tumors, are highly aggressive and mostly affect children and adolescents. Their molecular signature is a chromosomal translocation leading to the generation of EWS-ETS (or very rarely FUS-ETS) fusion proteins that are capable of transforming cells. These oncoproteins act as aberrant transcription factors due to the fusion of an ETS DNA binding domain to a highly potent EWS (or FUS) transactivation domain. Accordingly, many EWS-ETS target genes have been identified whose dysregulation could contribute to the development of tumor formation. Furthermore, EWS-ETS oncoproteins may impact on RNA splicing or affect other proteins through disturbing their ability to form functional complexes. The molecular knowledge gained so far from studying EWS-ETS oncoproteins has not only broadened our understanding of Ewing tumors but also improved the diagnosis of these highly undifferentiated tumors. In addition, several potential prognostic markers have been uncovered and novel therapies are suggested that may improve the still dismal survival rate of Ewing tumor patients.

Chromosomes, Human, Pair 16↗
PubMed2003

Human SLITRK family genes: genomic organization and expression profiling in normal brain and brain tumor tissue.

Slitrk family proteins are characterized as integral membrane proteins that have two leucine-rich repeat (LRR) domains and a carboxy-terminal domain that is partially similar to trk neurotrophin receptor proteins. The LRR domains are similar to those of slit proteins. In a previous study, we showed that mouse Slitrk genes are expressed predominantly in neural tissue and have neurite-modulating activity in cultured neuronal cells. Their expression profiles as well as their functions vary among the family members. In this paper, we characterized the human SLITRK1, SLITRK2, SLITRK3, SLITRK4, SLITRK5, and SLITRK6 genes. The six genes are located in three clusters, on 3q, 13q, and Xq, respectively. Their expression was detected mainly in the brain, but the expression profile of each SLITRK was unique. SLITRK expression was also investigated in various types of brain tumor tissue. The results showed that all SLITRK genes are differentially expressed in brain tumors, including astrocytoma, oligodendroglioma, glioblastoma, medulloblastoma, and supratentorial primitive neuroectodermal tumor (PNET). Particularly interesting findings were that SLITRK3 expression was enhanced in tissue from several different types of tumors and SLITRK6 expression was highly selective. These results suggest that the human SLITRK genes are useful molecular indicators of brain tumor properties.

Adolescent↗
PubMed1999

Evaluation of new monoclonal anti-MyoD1 and anti-myogenin antibodies for the diagnosis of rhabdomyosarcoma.

New monoclonal anti-MyoD1 and anti-myogenin antibodies were evaluated immunohistochemically to determine whether they are useful in discriminating rhabdomyosarcoma (RMS) from other soft tissue tumors in routinely processed sections. Neither MyoD1 nor myogenin was expressed in normal, mature striated muscle. In RMS, nuclear expression of MyoD1 and myogenin was found in 82 and 80% of non-overlapping cases, respectively. MyoD1 was generally expressed in small, primitive tumor cells, and larger cells exhibiting morphological evidence of skeletal muscle differentiation failed to express positive nuclear immunostaining. Positive nuclear staining for myogenin was stronger than that for MyoD1 in cases with abundant differentiated tumor cells, but was less prominent in cases in which small, primitive tumor cells predominated. No leiomyosarcomas, Ewing's sarcomas/peripheral primitive neuroectodermal tumors or other soft tissue tumors exhibited nuclear expression of MyoD1 or myogenin. In conclusion, both anti-MyoD1 and anti-myogenin antibodies are useful for diagnosing RMS and for discriminating RMS from other soft tissue tumors.

Actins↗
PubMed1989

Mitotic recombination of chromosome 17 in astrocytomas.

Allelic combinations at seven loci on human chromosome 17 defined by restriction fragment length polymorphisms were determined in tumor and normal tissues from 35 patients with gliomas. Loss of constitutional heterozygosity at one or more of these loci was observed in 8 of the 24 tumors displaying astrocytic differentiation and in the single primitive neuroectodermal tumor examined. The astrocytomas showing these losses included examples of each adult malignancy grade of the disease, including glioblastoma (malignancy grade IV), and seven of them demonstrated concurrent maintenance of heterozygosity for at least one chromosome 17 locus. Determination of allele dosage together with the genotypic data indicated that the tumor chromosomes 17 were derived by mitotic recombination in 7 of the 9 cases with shared homozygosity of the region 17p11.2-pter in all cases. In contrast, tumors of oligodendrocytic, ependymal, or mixed cellular differentiation did not exhibit loss of alleles at any of the loci examined. These data suggest that the somatic attainment of homozygosity for loci on chromosome 17p is frequently associated with the oncogenesis of central nervous system tumors, particularly those showing solely astrocytic differentiation, and that mitotic recombination mapping is a useful approach towards the subregional localization of a locus whose rearrangement is involved in this disease.

Astrocytoma↗