Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “NEUROFIBROMA”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,711 records · Page 95Linked to original sources
PubMed2006

cDNA microarray analysis of cancer associated gene expression profiles in malignant peripheral nerve sheath tumours.

BACKGROUND: Malignant peripheral nerve sheath tumour (MPNST) is a highly aggressive malignancy that arises within peripheral nerves, and is associated with poor prognosis. Little is known about the underlying biology of MPNST, especially the mechanisms involved in cell proliferation, invasion, or escape from apoptosis. AIMS: To identify genes differentially expressed in MPNST compared with benign tumours, such as neurofibromas and schwannomas, by means of cDNA microarray analysis. METHODS: Six MPNST cases and five benign cases (three schwannomas and two neurofibromas) were analysed. RESULTS: Six genes (keratin 18, survivin, tenascin C, adenosine deaminase, collagen type VIa3, and collagen type VIIa1) were significantly upregulated in MPNST, whereas one gene, insulin-like growth factor binding protein 6, was downregulated in MPNST. Survivin and tenascin C expression was validated by reverse transcription polymerase chain reaction. Immunohistochemistry confirmed upregulation of survivin in MPNST at the protein level in six of eight cases compared with benign tumours. Tenascin C was also expressed at the invasive front and tumorous stroma in all MPNST cases. MPNST cells expressed tenascin C in four of nine cases. CONCLUSIONS: Survivin and tenascin C may be associated with the malignant potential of MPNST and could be considered as potential therapeutic targets.

Adult↗
PubMed1978

Intrathoracic neural tumours.

The experience of one regional thoracic surgical unit in managing intrathoracic neural tumours over a 25-year period is presented. Neural tumour was diagnosed in 55 patients, of whom 41 were asymptomatic. In 11 patients complete resection was not achieved--the reasons for this and its effect on the outcome of the patient are discussed. There were 52 posterior mediastinal and three lateral chest wall tumours. The pathological distribution was as follows--benign nerve sheath tumours (neurofibroma, neurilemoma) 39, ganglioneuroma 13, and neuroblastoma 3. One neurofibroma recurred as a neurosarcoma six years after its apparently complete resection and was removed by an extensive resection at reoperation. One neuroblastoma recurred within the spinal canal four years after incomplete excision at thoracotomy--this patient died subsequently of widespread metastatic neuroblastoma. No other tumour is known to have recurred.

Adolescent↗
PubMed1988

Peripheral nerves of the extremities: imaging with US.

High-resolution real-time ultrasonography (US) was used to evaluate peripheral nerves of the extremities in healthy subjects and in 11 patients with a mass developed from a peripheral nerve. The normal median and ulnar nerves in the upper extremity and the normal sciatic and external popliteal nerves in the lower extremity were seen, all having an echogenic fibrillar echotexture. Pathologic findings included nine cases of benign tumor (four schwannomas, three neurofibromas, two traumatic neuromas), one of neurilemmitis, and one of tuberculoid leprosy. All lesions were hypoechoic. Three of the four schwannomas had well-defined contours, and two were associated with a typical distal sound enhancement. Neurofibromas and traumatic neuromas were less sharply delineated. Inflammatory conditions were characterized by a hypoechoic, thickened nerve. US was effective in imaging nerve masses in the extremities, and large normal nerves can now be demonstrated with high-resolution US.

Extremities↗
PubMed1991

Plasticity of integrin expression by nerve-derived connective tissue cells. Human Schwann cells, perineurial cells, and fibroblasts express markedly different patterns of beta 1 integrins during nerve development, neoplasia, and in vitro.

Strikingly selective expression patterns of beta 1, alpha 2, alpha 3, and alpha 5 integrin subunits were revealed in endoneurium, perineurium, and epineurium of fetal and adult human peripheral nerve by immunostaining with specific antibodies. The alpha 2 subunit was expressed only on Schwann cells both in fetal and adult nerve, whereas the alpha 3 epitopes were expressed exclusively in the adult tissue and were primarily present on perineurial cells. The alpha 5 epitopes were expressed only on the innermost cell layer of perineurium of fetal and adult nerve. The tumor cells within schwannomas and cutaneous neurofibromas expressed both alpha 2 and alpha 3 subunits, indicating that Schwann cells have the potential to express also the alpha 3 subunit in vivo. Cell cultures established from human fetal nerve and neurofibromas revealed expression of the alpha 2 and alpha 5 epitopes on Schwann cells, perineurial cells, and fibroblasts, whereas only Schwann cells contained the alpha 3 epitopes which were occasionally concentrated on the adjacent Schwann cells at cell-cell contacts. Our findings emphasize that nerve connective tissue cells change their profiles for expression of extracellular matrix receptors under conditions which have different regulatory control signals exerted by, for example, axons, humoral factors, or the extracellular matrix of the peripheral nerve. This plasticity may play an important role during nerve development and in neoplastic processes affecting the connective tissue compartments of peripheral nerve.

Antibodies, Monoclonal↗
PubMed2003

Congenital glaucoma and neurofibromatosis in a monozygotic twin: case report and review of the literature.

We describe a dramatic case of an identical twin presenting at birth with unilateral congenital glaucoma. Because of the suspicion of neurofibromatosis 1 a magnetic resonance image of the neural axis was obtained, which revealed a plexiform neurofibroma with spinal cord impingement. Diagnosis of neurofibromatosis 1 was confirmed by 3 months of age with the emergence of café-au-lait spots. This case was compared with all 19 reports published in the English literature of neurofibromatosis 1 associated with congenital glaucoma. Initial presentation, family history, characteristics ofthe clinical syndrome, and outcome of glaucoma in infants with neurofibromatosis 1 and congenital glaucoma were reviewed. A plexiform neurofibroma of the ipsilateral eyelid was present in eight patients and ipsilateral facial hypertrophy occurred in three patients. Café-au-lait spots appeared between the ages of 5 weeks and 8 years; none of the patients were reported to have café-au-lait spots at birth. Newborns with unilateral congenital glaucoma should raise high suspicion for neurofibromatosis 1 and its associated findings, which might need immediate intervention.

Cafe-au-Lait Spots↗
PubMed2006

Clinical phenotype of South African children with neurofibromatosis 1.

Forty-eight children with neurofibromatosis 1 presenting between 2000 and 2004 were reviewed for their clinical phenotype, and data were compared with published reports. The median age at presentation was 4 years (range 10 days to 12 years). The male to female ratio was similar (22 male:26 female). There were frequencies of café au lait spots, axillary freckling, Lisch nodules, and new mutations comparable to those cited in the literature. Fewer patients had neurofibromas (4%), but more patients had plexiform neurofibromas of the head and neck (16%). Three patients of the 22 who had neuroimaging had optic gliomas (14%). The most consistent disability, with maximum impact, related to the patient's cognitive level of functioning. School problems, defined as learning and behavioral problems observed in the classroom, were reported in 70% of school-aged children (n = 21), compared with international figures of 29.8% to 45%. This high prevalence has reinforced the clinic service policy of formal neuropsychology assessments in all children with reported school problems. In addition, earlier referral of children to the service (preschool n = 18) has enabled formal developmental assessments and planning of specific educational placement to optimize learning. This is the first description of the neurofibromatosis 1 phenotype from the African continent. The multidisciplinary approach to management has proved beneficial in the South African context. The combined clinic has resulted in a holistic approach to patient care, early detection of pathology, consistent therapies across the specialties, and better patient attendance and compliance. (J Child Neurol 2006;21:63-70).

Brain↗
PubMed1991

Familial spinal neurofibromatosis: clinical and DNA linkage analysis.

We studied two families with an unusual variant of neurofibromatosis (NF). The first family had spinal neurofibromas and café au lait spots (CLS), the second spinal neurofibromas without CLS. Other signs of NF1 or NF2, such as cutaneous tumors, Lisch nodules, or acoustic tumors, were absent. The inheritance pattern in both pedigrees was consistent with autosomal dominant inheritance. Using genetic linkage analysis with DNA markers tightly linked to the NF1 and NF2 loci, we determined that the likely location for the mutation in the first family was in the NF1 gene with odds of 97:1, whereas the mutation in the second family was excluded from the NF1 locus with odds greater than 100,000:1. Families such as these, in which a defined subset of the NF phenotype is passed on, are important for understanding the functional consequences of particular mutations in the NF genes.

Adolescent↗
PubMed1980

Suggested pathological basis of "redundant nerve root syndrome" of the cauda equina.

A clinical entity described as "redundant nerve root syndrome" of the cauda equina is reviewed. Eighteen reported cases with typical gross features are analyzed. Considerable speculation has existed regarding the pathogenesis of this syndrome, chiefly because the involved nerve root was not biopsied in the majority of instances. In one reported case, when the redundant root was examined histologically, a plexiform neurofibroma was found to be the cause of the thickening and redundancy of the nerve. In the case presented here, the enlarged nerve roots were part of a malignant plexiform neurofibroma with a short clinical course, and the tumor led to the death of the patient. It is suggested that biopsy of the involved nerve root is crucial in establishing the definitive diagnosis.

Adult↗
PubMed2006

Video-assisted thoracoscopic dissection of the brachial plexus: cadaveric study and illustrative case.

OBJECTIVE: Standard surgical approaches to the brachial plexus require an open operative technique with extensive soft tissue dissection. A transthoracic endoscopic approach using video-assisted thoracoscopic surgery (VATS) was studied as an alternative direct operative corridor to the proximal inferior brachial plexus. METHODS: VATS was used in cadaveric dissections to study the anatomic details of the brachial plexus at the thoracic apex. After placement of standard thoracoscopic ports, the thoracic apex was systematically dissected. The limitations of the VATS approach were defined before and after removal of the first rib. The technique was applied in a 22-year-old man with neurofibromatosis who presented with a large neurofibroma of the left T1 nerve root. RESULTS: The cadaveric study demonstrated that VATS allowed for a direct cephalad approach to the inferior brachial plexus. The C8 and T1 nerve roots as well as the lower trunk of the brachial plexus were safely identified and dissected. Removal of the first rib provided exposure of the entire lower trunk and proximal divisions. After the fundamental steps to the dissection were identified, the patient underwent a successful gross total resection of a left T1 neurofibroma with VATS. CONCLUSION: VATS provided an alternative surgical corridor to the proximal inferior brachial plexus and obviated the need for the extensive soft tissue dissection associated with the anterior supraclavicular and posterior subscapular approaches.

Adult↗
PubMed1995

Neurofibromin-deficient fibroblasts fail to form perineurium in vitro.

To identify cell type(s) that might contribute to nerve sheath tumors (neurofibromas) in patients with neurofibromatosis type 1, we generated cell cultures containing neurons. Schwann cells and fibroblasts from transgenic mouse embryos in which the type 1 neurofibromatosis gene was disrupted by homologous recombination (Brannan et al. (1994) Genes Development, 8,1019-1029). Normal fascicle formation by perineurial cells failed to occur in the absence of neurofibromin. Fascicles were reduced in number and showed abnormal morphology when normal neurons and Schwann cells were cultured up to 37 days with fibroblasts lacking neurofibromin. Proliferation was increased in a majority of fibroblast cell strains analyzed from embryos lacking neurofibromin. These observations suggest that mutations in the neurofibromatosis type I gene affect fibroblast behavior that might contribute to neurofibroma formation in patients with neurofibromatosis type 1.

Animals↗
PubMed2000

What are the CD34+ cells in benign peripheral nerve sheath tumors? Double immunostaining study of CD34 and S-100 protein.

To determine whether CD34 expression in nerve sheath lesions was found in a unique cell population or in a subset of nerve sheath cells, we performed double immunohistochemical staining using a standard avidinbiotin complex method with 2 separate color developing systems. We studied 40 neurofibromas and 16 neurilemomas. All lesions strongly expressed S-100 in nuclei and cytoplasm. CD34 was detected in cells having ameboid dendritic cytoplasm present in greatest numbers in Antoni B zones of neurilemomas, myxoid zones of neurofibromas, at the periphery of lobules in both tumor types, and condensed in apposition to perineurium. The CD34+ cells also were detected in normal nerves. They were infrequent in Antoni A zones of neurilemomas. No dual S-100 and CD34 expression was seen. This double immunostaining confirms the presence of a CD34-reactive non-Schwannian cell type in these neural neoplasms. As the CD34+, S-100-negative cell population is present also in normal nerves and infrequently seen in the areas of cellular neoplastic Schwann cells, CD34+, S-100-negative cells in peripheral nerve sheath tumors most likely are nonneoplastic and may have a supportive function.

Adolescent↗
PubMed1984

Glial fibrillary acidic protein (GFAP) immunoreactivity in peripheral nerve sheath tumors.

A spectrum of 24 benign and malignant nerve sheath tumors and 10 non-neural spindle-cell tumors were studied by light microscopy for the presence of glial fibrillary acidic protein (GFAP) immunoreactivity by the peroxidase-antiperoxidase (PAP) technique. In 8 cases, these results were compared to their electron microscopic appearances. Seventy percent (7 of 10) of benign schwannomas and 50% (4 of 8) of benign neurofibromas demonstrated focal to diffuse GFAP immunoreactivity. None of the malignant nerve sheath tumors nor any of the non-neural spindle-cell neoplasms contained demonstrable GFAP immunoreactivity. Similarly, no GFAP immunoreactivity could be detected in Schwann cells in normal peripheral nerves. The solitary benign schwannoma available for electron microscopic study demonstrated diffuse and abundant cytoplasmic intermediate filaments, and this tumor displayed diffuse and intense GFAP immunoreactivity. Two benign neurofibromas showed a more variable content of intermediate filaments ultrastructurally, and their GFAP immunoreactivity was variable. All five malignant nerve sheath tumors studied by electron microscopy displayed a variable complement of intermediate filaments; however, none of these tumors possessed GFAP immunoreactivity, suggesting that these intermediate filaments are either members of a different class of intermediate filaments or may perhaps represent "altered" GFAP not recognized by these antisera.

Cytoskeleton↗
PubMedDate not supplied

Ultrastructural study of a perineurioma.

A case of soft tissue tumor in the left brachialis muscle of a 49-year-old Japanese female patient was studied by electron microscopy. The tumor was diagnosed as intramuscular myxoma by light microscopy, but electron microscopic observation revealed that the tumor almost entirely consisted of cells similar to normal perineurial cells. The tumor cells possessed long, slender cytoplasmic processes covered by well-developed but discontinuous basal laminae, clusters of pinocytotic vesicles, and infrequent intercellular junctions. Perineurial cells have also been observed in other peripheral nerve lesions: neurofibromas, nerve sheath myxomas, and localized hypertrophic neuropathies. However, the term "perineurioma" or "perineurial cell tumor" should be reserved for discrete tumorous masses that are almost entirely composed of perineurial cells without evidence of residual axons, Schwann cells, fibroblasts, or tactile corpusclelike structures. Perineurioma may represent a third category of peripheral nerve sheath tumors, ultrastructurally distinct from schwannomas and neurofibromas.

Female↗
PubMed1993

Inhibition of angiogenesis and growth of human nerve-sheath tumors by AGM-1470.

The effectiveness of AGM-1470, a potent, fungal-derived inhibitor of angiogenesis, in suppressing the neovascularization and growth of human Schwann cell tumors was tested in six schwannomas, seven neurofibromas, and one neurofibrosarcoma. Tumor fragments from surgical specimens were implanted into the subrenal capsule of 348 nude mice (nu/nu). Seven days after implantation, the tumors were measured and vascularity was graded. The animals were then randomly assigned to one of two groups, to receive either saline (control group) or systemic AGM-1470 treatment. After 2 to 6 weeks of treatment, tumor size and degree of vascularity were recorded. In the six different schwannomas implanted into 138 mice, the average vascular grade in the control group after 2 weeks of treatment increased from 2.2 to 3.2 (+1.0), while in the AGM-1470-treated group it decreased from 2.2 to 1.7 (-0.5) (p < 0.01). In the seven different neurofibromas implanted into 158 mice, the change in the average vascular grade in control and AGM-1470-treated animals was +0.5 and -1.0, respectively (p < 0.01). In the one neurofibrosarcoma implanted into 52 mice, the change in average vascular grade in each group during the 6-week treatment period was +1.9 and -1.0, respectively (p < 0.01). Neurofibrosarcoma growth after 6 weeks of AGM-1470 treatment was only 8.5% of the growth found in the control animals (p < 0.01). This study determined that AGM-1470 is effective in inhibiting angiogenesis and the growth of human nerve-sheath tumors.

Animals↗
PubMed2005

Extrathecal intraradicular nerve sheath tumor.

OBJECT: The purpose of this study was to analyze the clinical profile of patients harboring extrathecal and intraradicular nerve sheath tumors (NSTs), located inside the sleeve of an extrathecal nerve root and very often within the proximal portion of the spinal nerve, and to evaluate the incidence of long-term dysfunction of the tumor-affected roots if resected. These tumors have not received particular attention in the literature. METHODS: A single-institution series of 16 patients who had undergone surgery for intraradicular NSTs during a 50-year period was selected retrospectively. Data pertaining to clinical features, tumor characteristics, and results of surgery were analyzed. CONCLUSIONS: Extrathecal and intraradicular neurofibromas or schwannomas more frequently affect the lumbar and S-1 nerve roots, often producing root pain only. Selective en bloc enucleation sparing at least part of the motor rootlets is possible for small schwannomas of the extrathecal-preganglion segment of the radix, whereas total resection of the affected root is generally required for radical removal of neurofibromas and large schwannomas. In the authors' experience, neither deafferentation pain nor severe radicular weakness occurs after division of the nerve root harboring the tumor.

Adolescent↗
PubMed2000

Spinal cord compression due to tumours at Kenyatta National Hospital, Nairobi.

OBJECTIVE: To determine the frequency of different types of tumours associated with cord compression, their mode of presentation and treatment outcome. DESIGN: Retrospective study. SETTING: Kenyatta National Hospital (KNH), a teaching and referral hospital in Nairobi, Kenya, from January 1985 to December 1994. SUBJECTS: Thirty eight patients. RESULTS: There were twenty one males and seventeen females with a male/female ratio of 1.3:1 and a mean age of 36.9 years. Primary spinal cord tumours were more common (65.8%) than metastatic tumours (34.2%). The commonest spinal cord tumour was meningioma (23.7%) followed by neurofibroma (15.8%). Most of the patients (70%) did not show any clinical improvement after surgery. CONCLUSION: Spinal cord tumours accounted for about 15% of all CNS tumours treated at the Kenyatta National Hospital. Most of the patients had total paralysis of the limbs at the time of presentation. Meningiomas and neurofibromas were the commonest cause of cord compression at KNH. Greater effort is needed to detect these tumours early when the signs and symptoms may be reversible following surgery.

Adolescent↗
PubMed1999

Extreme lateral transcondylar approach to the skull base.

In this study, the authors present their experience of using extreme later transcondylar approach (ELTC) for treating 7 patients with lesions in the anterolateral foramen magnum, upper cervical spine and cerebellopontine angle reaching upto jugular foramen. The tumours included meningiomas, neurofibromas (2 cases each), chondrosarcoma, epidermoid and aneurysmal bone cyst (one case each). The approach was used alone, in combination with retrolabyrinthine presigmoid approach in a patient with lower cranial nerve neurofibroma extending extracranially through the jugular foramen, or in combination with partial C1-C3 laminectomy in two patients with meningiomas situated anterolateral to the cord from the foramen magnum to C3. In two patients with extradural vertebral artery (VA) entrapment by a chondrosarcoma and aneurysmal bone cyst respectively, the vertebral artery was ligated distal to the tumour. The tumours were totally excised in five cases and partially in two. There was no preoperative mortality. The major complications included cerebrospinal fluid leak from the wound (3 cases) and increase in lower cranial nerve paresis (2 cases). At follow up, ranging from 6 months to 2 years, 5 patients showed no tumour recurrence. There was improvement in neurological status. One patient, with a partially excised aneurysmal bone cyst, showed no added deficits or increase in the tumour size. However, there was a massive regrowth in the patient with chondrosarcoma after 6 months. This technique provided a wide surgical exposure with direct visualization of the tumour-anterior cord interface, early proximal control of the VA and preservation of lower cranial nerves.

Adolescent↗
PubMedDate not supplied

[Brachial plexus tumors].

The brachial plexus is a primary site of tumours originating from peripheral nervous system, such as neurilemmoma and neurofibroma. Moreover, the brachial plexus is affected by various neoplasms spreading from the neighbouring anatomic structures. Surgical treatment of neoplasms provoking plexopathy is often realised by multidisciplinary teams. The authors present the series of 7 patients operated on for brachial plexus affection between 1993-2000, the pathologic findings were as follows: neurofibroma, neurilemmoma, lymphogranulomatosis, neurofibrosarcoma, lipoma, chordoma, sarcoma neurogenes. The analysis of clinical course includes: main symptoms, diagnostic procedures and results of treatment. Surgical technique is also described.

Adult↗