Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report a case of schwannoma (neurilemmoma) predominantly composed of small cells arranged in rosettes around central collagenous cores and discuss the differential diagnosis of this unusual variant. Schwannoma with giant rosettes, previously designated as neuroblastoma-like schwannoma by Goldblum et al., must be differentiated from neuroblastoma, peripheral neuroectodermal tumors, and malignant change in a schwannoma.
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PMID:Neuroblastoma-like schwannoma: a case report and review of the literature. 1254 97

Adrenal incidentalomas are a heterogeneous group of pathological entities, including benign or malignant adrenocortical or medullary tumors, hormonally active or inactive lesions, which are identified incidentally during the examination of nonadrenal-related abdominal complaints. About 1.5% to 23% of adrenal incidentalomas are pheochromocytomas. Composite pheochromocytoma is a rare tumour of adrenal medulla with divergente clinical course. This type of pheochromocytoma is designated "composite" or "mixed," depending on whether pheochromocytoma and nonpheochromocytoma components show the same embryologic origin. Nonpheochromocytoma components found in the composite pheochromocytoma include ganglioneuroma, ganglioneuroblastoma, neuroblastoma, and malignant schwannoma. The biologic behavior of composite pheochromocytomas may be as difficult to predict as more traditional pheochromocytomas; based on the number of cases reported to date the presence of areas resembling ganglioneuroblastoma or neuroblastoma does not necessary indicate a poor prognosis. Some may behave in a malignant fashion with metastasis by a component of the tumour which has neural features. Pheochromocytomas and paragangliomas are well-defined entities. Some of their nonsporadic associations and unusual morphological appearances are not universally appreciated. We report on a rare association of left adrenal CP, with typical right adrenal phochromocytoma and retroperitoneal paraganglioma, and a review of literature. We analyzed the clinical and immunohistochemical features in a 24-year-old woman with composite pheochromocytoma localized in the left adrenal gland and associated with blood pressure of 200/140 mmHg. Abdominal computed tomography and 131-J MIBG revealed a 65 x 60 mm mass in the right adrenal gland, but no revealed 45 x 40 mm retroperitoneal mass and 20 x 20 mm mass in the left adrenal region. Serum and urinary adrenaline levels were high, and catecholamine levels in the blood sample of the selective adrenal vein, were also high. Bilateral adrenalectomy and retroperitoneal mass were surgically removed without complications. Clinical symptoms were absent 6 years after surgery. After surgery the patient gave birth to two healthy babies. Immunohistochemical analyses revealed that tumour cells of right adrenal pheochromocytoma and retroperitoneal paraganglioma were strongly positive for neurone specific enolase, synaptophisin and chromogranin A. The left adrenal tumour showed pheochromocytoma, ganglioneuroma and neuroblastoma components. Immunoreactivity of this tumour added several features to the wide immunohistochemical spectrum. This case demonstrates the indolent behavior of sporadic-type CP and retroperitoneal paraganglioma in an adult patient. Unusual morphological features of CP occur in a substantial number of cases and may cause diagnostic problems.
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PMID:[Pheochromocytomas as adrenal gland incidentalomas]. 1258 98

To the best of our knowledge, a malignant ectomesenchymoma of the nose has not yet been reported. This rare tumour is composed of a mesenchymal element--usually a rhabdomyosarcoma--and a neuroectodermal element, often a neuroblastoma or a malignant schwannoma. Most malignant ectomesenchymomas have been found in children (mainly boys), but 5 adult cases, including our case, have also been reported. A 62-year-old man presented with a nasal obstruction on the right side of the nose. Diagnostic nasal endoscopy revealed a mass in the dorsal part of the right nasal cavity, which was treated by endoscopic surgery. The postoperative course was uneventful, and subsequent radiotherapy well tolerated. Since rhabdomyosarcoma is the most common component of this neoplasm, the treatment protocol for rhabdomyosarcoma would have appeared appropriate. This report reviews the literature, summarises the pathological features and possible histogenesis of the tumour, and outlines recommended treatments for malignant ectomesenchymoma.
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PMID:Malignant ectomesenchymoma of the nose. Case report and review of the literature. 1262 8

The current study disusses a new approach to the group of small round cell tumors (SRCTs) independently of their primary anatomical location. We perform this analysis supported mainly by morphological means and particularly with the help of immunohistochemistry and electron microscopy; the last of which continues to play a decisive role in their differential diagnosis. The microscopical similarity of many of these tumors often makes the diagnosis in routine histology extremely difficult, due to the varying degree of heterogeneity present, and may have important therapeutic and prognostic implications. Thus a correct final diagnosis is mandatory for the clinic. Within the group of tumors that express a dominant or occasional small round cell pattern "SRCT" (neoplasms of the Central Nervous System excluded) are included: Ewing's sarcoma and peripheral neuroectodermal tumor (Es/pPNET) comprising its varieties, neuroblastoma, desmoplastic small round cell tumor, rhabdomyosarcoma, alveolar, solid and embryonal, small cell osteosarcoma, chondrosarcoma, myxoid and mesenchymal, round cell and myxoid liposarcoma, synovial sarcoma (monophasic undiffentiated), primitive malignant peripheral nerve sheath tumor (malignant small cell schwannoma), malignant non-Hogdkin lymphoma, Merkel cell tumor of the skin (small cell carcinoma including neuroendocrine carcinoma). This study discusses in each case not only the histology, supported by immunohistochemistry, but also the main ultrastructural characteristics. We are conscious that in some cases further cytogenetic or molecular biology support may be necessary, when considering the limits of morphology today. Thus, short references on molecular genetics, complementing the structural findings, are given.
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PMID:Electron microscopy and other ancillary techniques in the diagnosis of small round cell tumors. 1269 73

Subfrontal schwannoma is a rare disease, which can be mis-diagnosed as an olfactory meningioma or a neuroblastoma, because of similar clinical symptoms and signs and neuroradiological features. Especially for young subjects, olfactory neuroblastoma should be carefully differentiated, since the management strategies for those lesions are significantly different. The craniofacial approach is often needed for the resection of a neuroblastoma. We report a case of 14-year old boy in which olfactory neuroblastoma was suspected prior to surgery, but turned out to be a schwannoma histologically. Molecular genetic examination revealed neither NF2 gene mutation nor loss of heterozygosity of chromosome 22q, unlike common schwannomas.
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PMID:Subfrontal schwannoma. 1582 81

In the past ten years, seven cases of schwannomas with giant fibrillar rosettes or perivascular rosettes have been reported. As these unusual variants of schwannomas had areas with hyperchromatic, small round cells recapitulating the appearance of a neuroblastoma, they received the descriptive name of neuroblastoma-like schwannomas. We herein report two additional cases of this unique variant of schwannoma and provide differential diagnostic considerations.
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PMID:Schwannoma with neuroblastoma-like rosettes: an unusual morphologic variant. 1590 Jan 31

Neuroectodermal tumor cells, like neural crest (NC) cells, are pluripotent, proliferative, and migratory. We tested the hypothesis that genetic programs essential to NC development are activated in neuroectodermal tumors. We examined the expression of transcription factors PAX3, PAX7, AP-2alpha, and SOX10 in human embryos and neuroectodermal tumors: neurofibroma, schwannoma, neuroblastoma, malignant nerve sheath tumor, melanoma, medulloblastoma, supratentorial primitive neuroectodermal tumor, and Ewing's sarcoma. We also examined the expression of P0, ERBB3, and STX, targets of SOX10, AP-2alpha, and PAX3, respectively. PAX3, AP-2alpha, and SOX10 were expressed sequentially in human NC development, whereas PAX7 was restricted to mesoderm. Tumors expressed PAX3, AP-2alpha, SOX10, and PAX7 in specific combinations. SOX10 and AP-2alpha were expressed in relatively differentiated neoplasms. The early NC marker, PAX3, and its homologue, PAX7, were detected in poorly differentiated tumors and tumors with malignant potential. Expression of NC transcription factors and target genes correlated. Transcription factors essential to NC development are thus present in neuroectodermal tumors. Correlation of specific NC transcription factors with phenotype, and with expression of specific downstream genes, provides evidence that these transcription factors actively influence gene expression and tumor behavior. These findings suggest that PAX3, PAX7, AP-2alpha, and SOX10 are potential markers of prognosis and targets for therapeutic intervention.
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PMID:Temporally regulated neural crest transcription factors distinguish neuroectodermal tumors of varying malignancy and differentiation. 1603 8

In response to different stress signals, the c-Jun NH(2)-terminal kinase (JNK) can trigger cell death. However, JNK also facilitates the survival and cell cycle progression of tumor cells by mechanisms that are poorly defined. Here, we show that schwannoma RN22 cells can survive and proliferate under serum-free conditions although serum withdrawal rapidly induces mitochondrial fission and swelling. Although the morphologic changes observed in the mitochondria did not trigger cytochrome c release, they were accompanied by an increase in the mitochondrial membrane potential (DeltaPsi(M)) and of immunoreactivity for active JNK in these organelles. Pharmacologic inhibition of JNK provoked a further increase of the DeltaPsi(M), an increase in reactive oxygen species (ROS) production, and a sustained decrease in cell viability due to necrosis. This increase in necrosis was prevented by the presence of ROS scavengers. Immunoreactivity for active JNK was also observed in the mitochondria of neuroblastoma 1E-115 and neuroblastoma 2a neuroblastoma cell lines on serum withdrawal, whereas active JNK was barely detected in serum-deprived fibroblasts. Accordingly, the reduction in neural tumor cell viability induced by JNK inhibition was largely attenuated in serum-deprived fibroblasts. These data indicate that local activation of JNK in the mitochondria can protect against necrotic cell death associated with ROS production, facilitating the growth of neural tumor cells subjected to serum deprivation.
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PMID:Mitochondrial c-Jun NH2-terminal kinase prevents the accumulation of reactive oxygen species and reduces necrotic damage in neural tumor cells that lack trophic support. 1721 Jul 97

Schwannoma and neurofibroma account for the majority of cutaneous benign peripheral nerve sheath tumors and usually pose little diagnostic difficulty in their classic forms. In rare instances, however, benign peripheral nerve sheath tumors may display epithelioid morphology and lack otherwise usual features of schwannoma or neurofibroma, making classification difficult. These unusual changes may prompt consideration of other benign neoplasms or a malignancy. Benign epithelioid peripheral nerve sheath tumor (BEPNST) is a somewhat non-specific term recently proposed to describe these neoplasms of imprecise histogenesis. Also diagnostically challenging, rare BEPNST with unusual arrangements of extracellular collagen have been described and reported as neuroblastoma-like schwannoma and collagenous spherulosis. We report a unique case of cutaneous BEPNST with a peculiar arrangement of abundant extracellular collagen, different than the previously observed patterns. Specifically, the neoplastic cells in this tumor were nearly obscured by the collagen, which formed large nodules and compressed the majority of the few remaining tumor cells to the periphery of the lesion. This excessive collagen production emphasizes the importance of adequate sampling to ensure a correct diagnosis.
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PMID:Collagen-rich variant of benign epithelioid peripheral nerve sheath tumor of the skin. 1819 Apr 49

A good examination in facial nerve imaging (CT or MR imaging) depends on a good knowledge of anatomy. Two clinical situations must be considered: imaging of patients with or without facial palsy. CT and MR imaging are very useful when the symptoms are atypical or progressive: MR imaging gives very good information about the facial nerve inflammation but may also discover a schwannoma, a hemangioma, a meningioma, or a primitive or secondary cholesteatoma. In malignant tumors of the parotid gland, a study of the fallopian canal must always be performed to delineate an extension in the mastoid, tympanic, or intrameatic parts. In some rare cases, a metastasis in the temporal bone may occur, especially in the region of the geniculate ganglion. Particular attention must be paid to children with facial palsy, considering the possibility of a histiocytosis or metastasis of a neuroblastoma.
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PMID:Pathology of the facial nerve. 1846 34


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