Neurofibroma

Intradural extramedullary (IDEM) cavernomas are rare vascular malformations. They are well-circumscribed dark berry-like lesions with a histologic appearance of sinusoidal vascular channels. Neurofibromas are the most common IDEM tumors, originating from all nerve elements and leading to firm enlargement of the affected nerve root. These lesions are completely different; however, they may involve the spinal nerve roots or the major nerve trunks. Any similarities in clinical findings are based on different pathophysiology. To present a rare resemblance of an IDEM cavernoma to a neurofibroma. This is a case report with review of the literature focused on the differential diagnosis. A 79-year-old patient presented with acute sensorimotor disturbance from L2-S1 levels. The investigations showed an L2-L3 lesion occupying the canal. Findings resembled a neurofibroma and a surgical resection was decided. The complete surgical resection revealed a vascular lesion originating from a nerve root. The histology confirmed an IDEM cavernoma. This is a unique case as such a clinical resemblance and a macroscopical appearance has not been reported for an IDEM cavernoma as yet. The patient showed full postoperative recovery from his initial symptoms. Intradural extramedullary cavernoma is a rare cause of compression to spinal cord or nerve roots. Its manifestation characteristics are well defined and should always be part of the differential diagnosis. Intraoperative findings aid the diagnosis in nontypical cases before the final histology. The nontraumatic and nerve tissue sparing surgical resection warrants optimal postoperative results and excellent prognosis.

Neurofibromatosis type 1 or von Recklinghausen's disease is one of the most common autosomal dominant genetic disorders. Between 29% and 77% of patients may suffer from a wide range of skeletal abnormalities and, thus, patients with neurofibromatosis frequently undergo skeletal scintigraphy, at which time the common peripheral nerve soft-tissue tumors that occur in this syndrome (neurofibromas, plexiform neuromas and neurofibrosarcomas) may be demonstrated. Single or multiphase 99mTc methylenediphosphonate (MDP) bone scans were performed in five patients with neurofibromatosis as part of their clinical evaluation. We imaged neurofibrosarcomas in three patients, cutaneous neurofibromas in one patient and a plexiform neuroma in one patient. Single- or multiphasic bone scans may localize common soft-tissue tumors in neurofibromatosis.

Neurofibromatosis type 1 (NF1) is a genetic disorder with a range of clinical manifestations such as widespread growth of benign tumours called neurofibromas, pain, learning disorders, bone deformities, vascular abnormalities and even malignant tumours. With the establishment of the Children's Tumour Foundation biobank, neurofibroma samples can now be collected directly from patients to be analysed by the larger scientific community. This work describes a pilot study to characterize one class of neurofibroma, cutaneous neurofibromas, by molecularly profiling of ~40 cutaneous neurofibromas collected from 11 individual patients. Data collected from each tumour includes (1) SNP Arrays, (2) Whole genome sequencing (WGS) and (3) RNA-Sequencing. These data are now freely available for further analysis at http://www.synapse.org/cutaneousNF.

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 segmen...

Children with neurofibromatosis type 1 (NF1) undergo costly surveillance scanning for a variety of asymptomatic central nervous system lesions whose natural history is poorly understood. We performed a 20-year retrospective chart review of 25 patients with clinically proven NF1 who required surgery (group A) and contrasted this cohort with 150 NF1 patients who did not require surgery (group B). In group A, 52% of patients underwent multiple procedures for more than one lesion (p = 0.043). Group A patients were further distinguished from those in group B by exhibiting a greater number of optic gliomas (p = 0.015), nonoptic intracranial tumors (p = 0.006), cranial nerve (p = 0.000), paraspinal (p = 0.0062), craniofacial (p = 0.001) and visceral (p = 0.03) neurofibromas and moyamoya disease (p = 0.00), as well as a higher frequency of seizure disorder, sphenoid wing dysplasia and poor academic performance. Gadolinium enhancement occurred in 43% of optic gliomas, 50% of parenchymal gliomas, 100% of cranial nerve, 100% of plexus, 67% of paraspinal, 50% of craniofacial and 50% of visceral neurofibromas in group A, while only 1 group B tumor enhanced. In group A, radiological progression occurred after a median of 4 years from initial diagnosis for optic gliomas as well as cranial nerve, plexus and visceral neurofibromas, 2 years for paraspinal neurofibromas and brainstem gliomas and 2.7 years for craniofacial neurofibromas. Only 1 tumor progressed in group B. Therefore, a small subgroup of NF1 patients (12.5%) who require treatment are at risk of subsequently needing further surgical attention, whereas a larger group of NF1 patients (87.5%) carry an indolent form of the disease. We recommend imaging for asymptomatic, gadolinium-enhancing lesions every 2 years for optic pathway and parenchymal gliomas and cranial nerve and visceral neurofibromas, and every year for brainstem gliomas and paraspinal as well as craniofacial neurofibromas. Nonenhancing optic pathway lesions could be followed up radiographically much less often since they do not show progression.

Oral tumors of presumably neuroectodermal origin were stained with anti-laminin antibody by a double layered immunofluorescence technique. A marked positive staining for laminin was found in neurofibromas and neurilemmomas although the pattern of laminin distribution was slightly different. Accentuated staining was seen in Verocay bodies. In granular cell myoblastomas (GCM), small groups of tumor cells were encircled by laminin-positive material, whereas individual tumor cells were unstained. In nevi, diffusely spread nevus cells were surrounded by a rim of laminin, whereas when arranged in nests whole groups of cells were encircled by laminin as seen in the GCM. Ordinary oral fibromas included as controls were negative except for the expected positive staining of basement membranes normally occurring in the tissues. Immunohistochemical demonstration of laminin seems to be a valuable aid in differential diagnosis of soft tissue tumors and may provide useful information about the pat...

✓Discovery that the Schwann cell is the primary cell type responsible for both the neurofibroma as well as the schwannoma has proven to represent a crucial milestone in understanding the pathogenesis of peripheral nerve tumor development. This information and related findings have served as a nidus for research aimed at more fully characterizing this family of conditions. Recent discoveries in the laboratory have clarified an understanding of the molecular mechanisms underlying the pathogenesis of benign peripheral nerve tumors. Similarly, the mechanisms whereby idiopathic and syndromic (NF1- and NF2-associated) nerve sheath tumors progress to malignancy are being elucidated. This detailed understanding of the molecular pathogenesis of peripheral nerve tumors provides the information necessary to create a new generation of therapies tailored specifically to the prevention, cessation, or reversal of pathological conditions at the fundamental level of dysfunction. The authors review t...

Introduction: Diagnosis of neurofibroma usually is based on the specific morphology and arrangement of mesenchymal cells in routine Hematoxylin and Eosin (H&E) sections, and detection of mast cells supports the diagnosis. Sometimes definite diagnosis from other mesenchymal lesions may be difficult. The aim of the present study was to compare S100 expression and mast cells count (as Gold Standard) with routine histopathologic diagnosis.

Methods: In this cross-sectional analytical study, all cases of neurofibroma and compatible/ consistent with neurofibroma, that had been diagnosed in department of oral & maxillofacial pathology, school of dentistry, Shiraz, from 1986 to 2013, were enrolled. Immunohistochemistry was performed using S100 antibody and slides were stained by Giemsa. S100 labeling index, intensity and distribution as well as mast cells count were evaluated using light microscope.

Results: Mast cells were present in 97% of cases that 56.4 % showed 1-200 cells/10HPF. 82 % of cases were positive for S100 that 40.7% showed 2-30% labeling index and 70.4% had moderate intensity for S100 staining.

Conclusions: The comparison of routine histopathologic examination with gold standard method in Oral Pathology Department of Shiraz Dental School confirmed the routine histopathologic diagnosis in all cases, therefore no more evaluation may be required if a pathologist considers all routine diagnostic criteria.

Neurofibroms are benign peripheral nerve sheath tumor
comprising of an admixture of fibroblasts, Schwan cells,
and perineurial cells.1 Clinically, neurofibromas may present
either as solitary lesion or as a part of the generalized
syndrome of neurofibromatosis.2 Oral neurofibromas are
unusual and occurrence of these on gingiva is even
more rare. Neurofibromas can be diagnosed by histopathological
features and by immunohistochemistry.
They show a positive expression for S-100 marker.1 We
present a case of solitary oral neurofibroma with a
positive immunohistochemical expression for S-100.

The findings of this study show that Class III β-tubulin is a component of the mitotic spindle in multiple cell types. Class III β-tubulin has been widely used as a neuron-specific marker, but it has been detected also in association with breast and pancreatic cancers. In this study, we describe a novel finding of Class III β-tubulin in a subpopulation of cells in malignant peripheral nerve sheath tumor. The findings of this study also show that Class III β-tubulin is expressed by normal mesenchymal and epithelial cells (fibroblasts and keratinocytes), two transitional cell carcinoma cell lines, and neurofibroma Schwann cells, as shown by immunolabeling and Western transfer analysis using two different Tuj-1 antibodies that are specific for Class III β-tubulin. The corresponding mRNA was detected using RT-PCR and whole human genome microarrays. Both antibodies localized Class III β-tubulin to the mitotic spindle and showed a colocalization with α-tubulin. The immuno-reaction became ...

ABSTRACT A 19-year-old man with a history of neurofibromatosis type 1 was referred for resection of a lesion on the left side of the lumbar spine. The lesion had been growing (4.5 cm/69% increase of the largest dimension over the last 5 years) but had never caused any pain. F-18-fluorodeoxyglucose-positron emission tomography/computed tomography (F-18-FDG) showed heterogeneous uptake within this single lesion. Initial histopathology of a low metabolic area showed benign neurofibroma. However, at definitive pathologic evaluation malignant transformation was detected in a region with high F-18 FDG uptake. Thus, false reassurance caused by a sampling error was prevented by F-18-FDG-positron emission tomography/computed tomography.

INTRODUCTION Solitary neurofibromas are benign tumors, often the manifestation of neurofibromatosis, and reflect a hereditary pathology with several variants. The clinical manifestations of solitary neurofibromas change according to their location and can generate a variety of symptoms. Usually, solitary neurofibromas are located in the skin and rarely in other places. Surgical removal is the only treatment; malignant transformation and recurrence are unusual. OBJECTIVE A case is reported of solitary neurofibroma in the abdominal wall of a 19-year-old patient without neurofibromatosis. MATERIALS AND METHODS Articles included are from Proquest, Pubmed and Ovid databases. Key words used were neurofibroma, tumors of the neural sheath, and case report. The search is current as of May 24, 2007. CONCLUSIONS This case appears to be the first one with these characteristics reported in the English and Spanish medical literature.

The posterior mediastinum is the potential space along each side of the vertebral column and adjacent proximal portions of the ribs--the paravertebral sulci. From the posterior mediastinal tumors, the most commonly encountered are the neurogenic tumors (75%), the remaining 25% are represented by a heterogenous group of rare tumors including teratoma, lymphoma, sarcoma and other lesions arising outside the mediastinum and projecting into the posterior compartment. Surgical excision, by thoracotomy or miniinvasive techniques, is the first line of treatment in the posterior mediastinal tumors. Tumors with extension into the spinal canal (dumbbell tumors), accounting for nearly 10% of the posterior mediastinal tumors, require a multidisciplinary approach: thoracic surgeon and neurosurgeon. We present the experience of the "Carol Davila" University of Medicine and Pharmacy Thoracic Surgery Clinic in the surgery of neurogenic posterior mediastinal tumors throughout a 9 year period (2001 - 2010). 42 cases admitted and operated in this period are being analysed.

Object The authors focus on injury mechanisms involved in 1019 operative brachial plexus injuries (BPIs) managed between 1968 and 1998 at Louisiana State University Health Sciences Center (LSUHSC). Methods Data regarding these mechanisms of injury were obtained via retrospective chart reviews of patients who had undergone operations at LSUHSC. Five main mechanisms of injury to the brachial plexus occurred in the series. These included 509 stretch/contusion injuries (49%) with four patterns of presentation in 366 patients: 208 C5–T1 nerve injuries; 75 C5–7, 55 C5–6 injuries; and 28 involving the C8–T1 or C7–T1 nerves. Stretch/contusion injury was followed in frequency by gunshot wound (GSW), resulting in 118 injuries (12%). Most of the 293 involved plexus elements had some gross continuity when surgically exposed. Seventy-one lacerations involved the brachial plexus (7%), including 83 sharp lacerations caused by knives or glass; 61 blunt transections due to automobile metal, fan, and...

Neurofibroma is a benign peripheral nerve sheath tumour. It is one of the most frequent tumours of neural origin and its presence is one of the clinical criteria for the diagnosis of type 1 neurofibromatosis (NF-I). Neurofibromatosis type 1 is an autosomal dominantly inherited disease due to an alteration in the long arm of chromosome 17. About 50% of NF-I patients have no family history of the disease. NF-I patients have skin lesions (cafe au lait spots and neurofibromas) as well as bone malformations and central nervous system tumours. Diagnosis is based on a series of clinical criteria. Gingival neurofibroma in NF-I is uncommon. Treatment of neurofibromas is surgical resection. The aim of this paper is to report a case of NF-I with gingival involvement and to review the literature.

Neurofibroma of the male breast outside of neurofibromatosis is extremely rare with only one previous case having been reported. A 48 year old male patient with a neurofibroma in the breast presenting with gynaecomastia is reported. Clinical and mammogram findings with fine needle aspiration cytology and full histology are presented. To our knowledge this is only the second case of a neurofibroma in a male breast in the English literature and the first report to include the mammographic findings.

Peripherin is an intermediate filament involved in growth and development of the peripheral nervous system, and is produced by neurons and the beta cells of the islets of Langerhans. Recently, malignant melanomas and some melanocytic nevi have been shown to express peripherin. It is unknown if Schwann cells, also derived from the neural crest, express peripherin. Expression of peripherin was evaluated by immunohistochemistry in cutaneous lesions characterized by a prominent Schwann cell component including 26 neurofibromas (NF), 10 schwannomas (SCH), seven granular cell tumors, and five palisaded encapsulated neuromas (PEN); 13 neurotized melanocytic nevi (NMN) also were evaluated because these lesions contain Wagner-Meissnerlike structures and type C nevus cells, which exhibit a "schwannian" phenotype. Peripherin was detected in the axons of normal peripheral nerves. NF and PEN contained numerous axons dispersed throughout the lesions, whereas only scattered small nerves were seen in GCT. In SCH, only rare axons were labeled, mostly at the periphery of the lesions. All other cells in these four types of lesions, therefore including Schwann cells, were not labeled. In most NMN, labeled axons were identified within the lesions. In a few cases, rare epithelioid melanocytes within the superficial portions of the nevi were labeled. The Wagner-Meissnerlike structures and type C nevus cells (schwannian) were not labeled in any lesion; however, numerous labeled axons invested these areas. Because there are different relative numbers of peripherin-labeled axons throughout NF, PEN, some nevi, and SCH, analysis of peripherin expression may be helpful in the diagnosis of these lesions. Neurons and some epithelioid melanocytes, in contrast to type C nevus cells and Schwann cells of NF and SCH, express peripherin, providing further evidence for a transition from a more neuronal to a more schwannian phenotype during the normal maturation sequence of melanocytes in nevi.