Malignant schwannoma of the mandible

Neurofibrosarcoma of the mandible derived from neurofibromatosis

Neurofibrosarcoma is a rare malignant neoplasm of the head and neck region and accounts for 8% to 16% of all cases. Its origin is varied and may stem from cells of the peripheral nerves, develop de novo, or result from malignant transformation of preexisting neurofibromas. Because the features of neurofibrosarcomas are heterogeneous, the data retrieved during clinical examinations are of great aid for diagnosis. In this case, owing to clinical features and the fact that the patient had neurofibromatosis type 1, the hypothesis of neurofibrosarcoma was promptly established. The final diagnosis was confirmed by associating clinical, imaging, and pathological data. After the treatment, the patient has been followed up for 10 years, with no evidence of recurrence.

Solitary intraosseous schwannoma of the base and vault of the skull: a summary review of such unusual location

Intra-osseous schwannoma is a rare mesenchymal tumor. Although, the head and neck region is one of the most common sites for schwannomas, its location at the skull bone is uncommon and accounted for less than 0.2% in the largest series of bone tumors ever reported. Furthermore, it is most often a benign tumor, malignant transformation is exceedingly rare. Clinical presentation is non-specific, most often symptoms are associated with compression and invasion of adjacent organs. Neuro-imaging features are non-specific and the diagnosis is based on histological examination with immunohistochemical study. Surgery remains the aim of treatment. However, radiation therapy could be an interesting therapeutic option in unresectable tumors. This systemic review offers new clinicopathological data useful for better defining the diagnosis and clinicopathological behavior of schwannoma. The purpose of this work is to raise awareness among clinicians adding this clinical entity as a differential diagnosis when a mass of skull bone is identified.

An intraosseous malignant peripheral nerve sheath tumor of the lumbar spine without neurofibromatosis: Case report and review of the literature

A malignant peripheral nerve sheath tumor (MPNST) is defined as any malignant tumor that develops or differentiates from cells in the peripheral nerve sheath. This tumor is commonly associated with neurofibromatosis type 1 (NF1) and previous radiotherapy treatment. Primary intraosseous MPNSTs are extremely rare and a case of the lumbar spine in a patient without NF1 is reported in the present study, with a review of the intraosseous MPNST literature. A 45-year-old female presented with a 1-month history of severe lower back pain and pain radiating to the left leg. A total en bloc spondylectomy of L4 was performed. The postoperative histopathological diagnosis was MPNST with deletion of NF1, confirmed by dual-color fluorescence in situ hybridization (FISH) analysis. The tumor recurred 1 month following the surgery. Although adjuvant chemotherapy was administered, the patient succumbed due to intramedullary dissemination and carcinomatous meningitis 8 months following the initial consultation. NF1 deletion by FISH analysis may be particularly useful in distinguishing MPNST from other high-grade malignancies with overlapping morphological features.

Spinal cord compression revealing an intraosseous schwannoma

A 68-year-old female presented with inflammatory lumbalgia and cruralgia. Physical examination revealed a lumbar stiffness without neurological deficit. Secondarily, paraplegia and urinary retention appeared. Magnetic resonance imaging showed a vertebral compaction of L3 vertebra with medullar compression. Emergent surgery revealed an epidural tumor involving largely the L3 vertebral body. Histology found schwannoma with positive protein S100 on the immunohistochemical study. Metastasis screening revealed bilateral nodular lesions of the lungs and a trochanter high scintigraphic signal. It was a malignant schwannoma. The patient underwent radiotherapy in addition to the total tumor resection.

Malignant schwannoma of the mandible: A case report

This article describes a 59-year-old woman with a rare malignant schwannoma invading the left mandible. The clinical, radiological, pathological findings, treatment, and prognosis of our patient are discussed in detail. A 4-year cure was achieved by radical surgery and concurrent chemoradiotherapy (CCRT). In addition, we also review and summarize relevant literature on malignant schwannoma.

Extensive malignant schwannoma of the mandibular nerve. Case report

An extensive malignant schwannoma of the mandibular nerve in an 8-year-old boy is presented. The clinical presentation, light microscopic findings, and radiographic features are described. The patient was successfully treated with surgery in combination with chemotherapy. He is still well, without evidence of metastasis or local recurrence, 5 years postoperatively.

Peripheral nerve sheath differentiation in malignant soft tissue tumours: an ultrastructural and immunohistochemical study

Thirteen soft tissue sarcomas with ultrastructural evidence of nerve sheath differentiation were investigated by immunohistochemistry. Three arose in a major nerve or nerve trunk and four patients had von Recklinghausen's neurofibromatosis. Ultrastructurally, 10 cases showed variable differentiation towards Schwann cells, two resembled perineurial cells and one tumour had features suggestive of both cell types. Immunostaining for S-100 protein was positive in eight Schwann cell tumours, negative in the other two Schwann cell tumours and negative in those with perineurial-like cells. No cases demonstrated epithelial membrane antigen, so that the existence of perineurial cells in malignant nerve sheath tumours remains immunohistochemically unsubstantiated; it may be that the perineurial-like cells are merely incompletely differentiated Schwann cells, with nerve sheath differentiation manifesting a continuous spectrum. Leu 7 was detected in four Schwann cell tumours, three of which were ultrastructurally well differentiated. Cytokeratin and desmin were demonstrated only in an undifferentiated pleomorphic area of one Schwann cell tumour. Electronmicroscopy can aid diagnosis by revealing nerve sheath differentiation in malignant soft tissue tumours without demonstrable S-100 protein.

Malignant melanotic schwannoma of the oral cavity

Intraoral malignant melanotic schwannoma is an extremely rare tumor. Two cases are presented, one occurring in the mandible of a 62-year-old man, the other in the maxilla of a 79-year-old man. The clinical presentation, light microscopic findings and immunohistopathological features are described. The difficulty of diagnosing this special tumor at initial presentation correctly, is discussed.

Central neurilemmoma (schwannoma) of the mandible. Case report

A neurilemmoma presenting as a central bone tumour is uncommon with less than 40 cases having been reported in the jaws. A further case of intraosseous (central) neurilemmoma arising in the posterior mandible of a 55 year old Vietnamese woman is presented with discussion on the incidence, clinical presentation, radiographic appearance, histology and treatment of this benign neurogenic tumour.