Nerve sheath tumors are not frequent in the head and neck area. They might arise from large or small units of cranial, cervical and brachial plexuses as well as the cervical symphatic nerves. Their clinical course and findings are not similar, and preoperative diagnosis are extremely difficult in some cases. We experiencd eighteen cases of extracranial nerve sheath tumors in the head and neck regions during the past six years Twelve of them were schwannomas, and six of them were neurofibromas which did not associate with Von Recklinghausen's diseases. This analysis of eighteen cases and two representative cases are reported with literature review.
Brachial Plexus ; Diagnosis ; Head* ; Neck* ; Nerve Sheath Neoplasms* ; Neurilemmoma ; Neurofibroma

A malignant peripheral nerve sheath tumor (MPNST) is an extremely rare soft tissue tumor in the general population. On the other hand, there is a higher incidence of MPNST in patients with neurofibromatosis type I (von Recklinghausen's disease). The common sites are the extremities, trunk, head and neck. However, an intraabdominal or intrathoracic manifestation is uncommon. This paper reports two patients, a 31 year-old woman with multiple neurofibromatosis presenting as an intraabdominal malignant peripheral nerve sheath tumor, and a 33 year-old woman with an intrathoracic malignant peripheral nerve sheath tumor. The patients were treated with chemotherapy followed by radiotherapy. However, one patient died as a result of disease progression 21 months after the diagnosis and the other patient is currently being treated with radiotherapy.
Abdominal Neoplasms/*diagnosis ; Adult ; Female ; Humans ; Nerve Sheath Tumors/*diagnosis ; Neurofibromatosis 1/*complications ; Thoracic Neoplasms/*diagnosis

Schwannomas are benign nerve sheath tumors that can present in various locations and they have variable symptoms. However, schwannoma of the superficial peroneal nerve is rare, and only a limited number of cases have been reported. The authors here describe a case of schwannoma of the superficial peroneal nerve, which was initially considered as a L5 radiculopathy because of its clinical similarity. In the differential diagnosis of nontraumatic and nonarthritic pain of the lower leg and foot, benign tumors, particularly schwannomas of the peroneal nerves should be considered. Treatment by excision can result in relief of the symptoms and maintenance of function.
Diagnosis, Differential ; Foot ; Leg ; Nerve Sheath Neoplasms ; Neurilemmoma* ; Peroneal Nerve* ; Peroneal Neuropathies ; Radiculopathy ; Sciatica*

PURPOSE: To identify the differential MRI findings between myxoid tumors and benign peripheral nerve sheath tumors (BPNSTs) in the musculoskeletal system. MATERIALS AND METHODS: The study participants included a total of 35 consecutive patients who underwent MRI between September 2011 and December 2013. The patients were pathologically diagnosed with myxoid tumors (22 patients) or BPNSTs (13 patients). Evaluation was done by two radiologists, based on the following characteristics: size, margin, degree of signal intensity (SI) on T2-weighted images (T2WI), homogeneity of SI on T2WI, enhancement pattern, enhancement homogeneity, presence of cystic portion, internal fat component, presence of fat split sign, presence of target sign, presence of continuation with adjacent neurovascular bundle, and presence of surrounding halo. RESULTS: Large size, high SI on T2WI, heterogeneous enhancement, and internal fat component were commonly observed in myxoid tumors, while homogenous enhancement, fat split sign, target sign were common in BPNSTs. The differences were statistically significant (P < 0.05). Other findings, such as margin, homogeneity of SI on T2WI, enhancement pattern (peripheral or solid), internal cystic portion, continuation with neurovascular bundle, and surrounding halo, did not show significant difference between myxoid tumors and BPNSTs (P > 0.05). CONCLUSION: In the differential diagnosis of myxoid tumors and BPNSTs involving the musculoskeletal system, several MRI findings such as degree of SI on T2WI, enhancement homogeneity, internal fat component, fat split sign, and target sign, may be helpful in establishing the diagnosis.
Diagnosis ; Diagnosis, Differential ; Humans ; Magnetic Resonance Imaging* ; Musculoskeletal System* ; Nerve Sheath Neoplasms* ; Peripheral Nerves*

Ancient schwannoma is a benign neoplasm of nerve origin and may cause difficulties in the differential diagnosis with other benign or malignant tumors. It is also a rare variant of schwannoma with atypical tumor cells with nuclear pleomorphism and hyperchromatism. In this report, a 44-years-old female patient with an ancient schwannoma of the submandibular gland is presented, discussed, and the literature is reviewed for head and neck location of this tumor.
Diagnosis, Differential ; Female ; Head ; Humans ; Neck ; Nerve Sheath Neoplasms ; Neurilemmoma ; Submandibular Gland

Peripheral nerve sheath tumors rarely occur in the oral cavity and include neurofibroma, schwannoma, and palisaded encapsulated neuroma. We report a rare case of benign peripheral nerve sheath tumor of the tongue. This tumor was a 0.8 x 0.5 cm sized, firm mass on the left lateral surface of the tongue. Histologically, this mass was composed of well- circumscribed variable sized nodules, which consisted of moderately cellular spindle cells with vague nuclear palisading and a small amount of fibrous tissue. Most of the tumor cells were strongly positive for S-100 protein, but negative for epithelial membrane antigen on immunohistochemistry. No axons were found by immunostaining for neurofilament and Bodian stains. In addition, the surrounding, compressed, fibrous tissue showed rare EMA- positive cells. The present case might be a rare case of neurofibroma arising in the tongue, although immunohistochemical and special stains did not support such a diagnosis.
Adult ; Case Report ; Female ; Human ; Immunohistochemistry ; Nerve Sheath Tumors/chemistry/diagnosis/*pathology ; S100 Proteins/analysis ; Tongue Neoplasms/chemistry/diagnosis/*pathology

Biopsy ; Humans ; Male ; Middle Aged ; Muscle Neoplasms ; diagnosis ; pathology ; Neoplasm Metastasis ; Nerve Sheath Neoplasms ; diagnosis ; pathology ; Recurrence ; Sciatic Nerve ; pathology ; Tomography, X-Ray Computed

A 51-year-old woman was presented with a palpable mass in the infraauricular area that had existed for 4-months. The mass from the superficial lobe of the parotid gland was 2.7 cm in the greatest dimension and was ill-defined with rubbery, homogeneous, and fibrotic appearance. Histologically, the lesion was infiltrative into the lobules of the paratid gland, and was composed of a proliferation of spindle or stellate cells with cellular and sclerotic areas. On immunohistochemistry, the cells were only positive for vimentin and focally for smooth muscle actin. Differential diagnosis from nerve sheath tumors and solitary fibrous tumors involving the parotid gland was emphasized.
Actins ; Diagnosis, Differential ; Female ; Fibroma* ; Humans ; Immunohistochemistry ; Middle Aged ; Muscle, Smooth ; Nerve Sheath Neoplasms ; Parotid Gland* ; Solitary Fibrous Tumors ; Vimentin

Ancient schwannoma is a rare variant of schwannoma and a slow growing benign tumor associated with degeneration that may be diagnosed as a malignant tumor, because it presents with a large size and an inhomogeneous signal intensity. The main differential diagnosis of plexiform soft tissue tumor includes plexiform neurofibroma, malignant peripheral nerve sheath tumor (MPNST). In this case, we describe the MRI findings in a case of ancient schwannoma involving left thigh of a 63-year-old woman mimicking a plexiform MPNST. The tumor appeared as an inhomogeneous signal intensity and multinodular appearance, causing misdiagnosis as a plexiform MPNST.
Diagnosis, Differential ; Diagnostic Errors ; Female ; Humans ; Middle Aged ; Nerve Sheath Neoplasms ; Neurilemmoma ; Neurofibroma, Plexiform ; Peripheral Nerves ; Thigh

Schwannoma or neurilemmoma is a benign peripheral nerve sheath tumor that arises from Schwann cells. Approximately 25–45% of all schwannomas occur in the head and neck regions, and the intraoral presentation of these is only 1%. We report a rare case of a patient presenting tongue base schwannoma with characteristic imaging features on computed tomography and magnetic resonance imaging.
Diagnosis, Differential ; Head ; Humans ; Magnetic Resonance Imaging ; Neck ; Nerve Sheath Neoplasms ; Neurilemmoma ; Peripheral Nerves ; Schwann Cells ; Tongue