1/61. Pigmented schwannoma of the ventral spinal cord.Pigmented schwannomas of the spinal canal are rare entities. We present a case of such in an unusual, ventral intradural, extramedullary location in a 27-year-old man. Imaging and histopathologic findings, including electron microscopy, showed an intradural, extramedullary pigmented schwannoma, densely adherent to the leptomeninges of the anterior median septum. This lesion is demonstrative of the neuroectodermal origin of these lesions and represents a rare location of these tumors.- - - - - - - - - - ranking = 1keywords = pigmented (Clic here for more details about this article) |
2/61. Primary melanocytic schwannoma of cervical sympathetic chain.BACKGROUND: Primary melanocytic schwannoma arising from the cervical sympathetic chain is a rare pigmented nerve sheath tumor. Two cases are presented from an academic medical center. patients and methods patients were initially seen with an enlarging neck mass associated with sympathetic nervous system dysfunction. radiography demonstrated a mass located posterior to the carotid sheath. Primary therapy consisted of surgical excision and postoperative radiation therapy. RESULTS: The tumors were found to be melanocytic schwannomas arising from the cervical sympathetic chain. The pathologic characteristics of this neoplasm are reviewed. One patient remained disease free for 12 years after treatment, whereas 1 patient died as a result of local recurrence and distant metastases. CONCLUSIONS: Melanocytic schwannoma of the cervical sympathetic chain is a rare nerve sheath tumor of the head and neck that may be misdiagnosed as malignant melanoma. The clinical behavior of this neoplasm is variable. Preoperative neurologic findings, anatomic location, electron microscopy, and immunohistochemistry findings help to establish the diagnosis, and electron microscopy may have a role in distinguishing between benign and malignant lesions. Complete surgical excision is the treatment of choice.- - - - - - - - - - ranking = 58.203407501951keywords = melanocytic, pigmented (Clic here for more details about this article) |
3/61. Neurosurgical implications of carney complex.OBJECT: The authors present their neurosurgical experience with carney complex. carney complex, characterized by spotty skin pigmentation, cardiac myxomas, primary pigmented nodular adrenocortical disease, pituitary tumors, and nerve sheath tumors (NSTs), is a recently described, rare, autosomal-dominant familial syndrome that is relatively unknown to neurosurgeons. neurosurgery is required to treat pituitary adenomas and a rare NST, the psammomatous melanotic schwannoma (PMS), in patients with carney complex. Cushing's syndrome, a common component of the complex, is caused by primary pigmented nodular adrenocortical disease and is not secondary to an adrenocorticotropic hormone-secreting pituitary adenoma. methods: The authors reviewed 14 cases of carney complex, five from the literature and nine from their own experience. Of the 14 pituitary adenomas recognized in association with carney complex, 12 developed growth hormone (GH) hypersecretion (producing gigantism in two patients and acromegaly in 10), and results of immunohistochemical studies in one of the other two were positive for GH. The association of PMSs with carney complex was established in 1990. Of the reported tumors, 28% were associated with spinal nerve sheaths. The spinal tumors occurred in adults (mean age 32 years, range 18-49 years) who presented with pain and radiculopathy. These NSTs may be malignant (10%) and, as with the cardiac myxomas, are associated with significant rates of morbidity and mortality. CONCLUSIONS: Because of the surgical comorbidity associated with cardiac myxoma and/or Cushing's syndrome, recognition of carney complex has important implications for perisurgical patient management and family screening. Study of the genetics of carney complex and of the biological abnormalities associated with the tumors may provide insight into the general pathobiological abnormalities associated with the tumors may provide insight into the general pathobiological features of pituitary adenomas and NSTs.- - - - - - - - - - ranking = 2keywords = pigmented (Clic here for more details about this article) |
4/61. Choroidal schwannoma: immunohistochemical and electron-microscopic study.Schwannoma (neurilemoma) arising from the ciliary body and choroid is a rare form of intraocular tumor and usually misdiagnosed clinically as amelanotic melanoma. This case report describes a 73-year-old woman who developed a large nonpigmented intraocular tumor of the choroid in the left eye and underwent enucleation with a clinical diagnosis of malignant melanoma. The tumor consisted of spindle-shaped cells with an indefinite cytoplasm and twisted nuclei, which had positive immunoreactivity for S-100 protein, vimentin, glial fibrillary acidic protein and neural cell adhesion molecule. A continuous basal lamina encompassing the tumor cells was demonstrated by immunostaining for laminin and type IV collagen. Ultrastructurally, tumor cells with scant organelles had delicate cytoplasmic processes apposing each other, all indicative of Schwann cell origin. In reexamination of fluorescein angiograms, ultrasonograms and magnetic resonance images, no findings were incompatible with a diagnosis of choroidal melanoma. Histopathological studies showed that the tumor was a schwannoma. At present, we do not have a benchmark for the clinical diagnosis of intraocular schwannoma.- - - - - - - - - - ranking = 1keywords = pigmented (Clic here for more details about this article) |
5/61. Psammomatous melanotic schwannoma: presentation of a rare primary lung tumor.A 30-year-old nonsmoking man underwent a left lower lobectomy with bronchoplasty for an obstructing lesion of the left lower lobe. pathology results demonstrated a psammomatous melanotic schwannoma, a rare pigmented neural tumor of which only 25 cases have been reported as originating in the respiratory tract.- - - - - - - - - - ranking = 1keywords = pigmented (Clic here for more details about this article) |
6/61. Malignant schwannoma with melanocytic differentiation arising in a patient with neurofibromatosis.A 50-year-old woman with von Recklinghausen's disease, but not Carney's complex, presented with a 1-year history of a hard subcutaneous mass on her right hip and right inguinal lymphadenopathy. Histological and immunohistochemical studies of the tumour revealed schwannian and melanocytic characteristics. Local recurrence without distant metastases was observed 5 years later. Although the diagnosis of malignant schwannoma with melanocytic differentiation, rather than neurotropic melanoma, was made for the primary tumour, based on the clinicohistopathological and ultrastructural findings, the overall clinical course in this case did not seem incompatible with malignant melanocytic schwannoma.- - - - - - - - - - ranking = 66.737308752276keywords = melanocytic (Clic here for more details about this article) |
7/61. Sinonasal mucosal malignant melanoma: report of an unusual case mimicking schwannoma.Primary mucosal melanoma of the sinonasal tract is a rare malignancy that has a more aggressive clinical course than its cutaneous counterpart. The histology of these lesions varies, with differing degrees of melanin production and an epithelioid or spindle-cell growth pattern. Cutaneous melanocytic lesions may differentiate in accordance with their neural crest derivation and express morphology similar to nerve sheath tumors. We believe the following case study reports the first instance of a mucosal melanoma with a Schwannian pattern of growth, arising from the nasal cavity of a 26-year-old man.- - - - - - - - - - ranking = 9.5339012503252keywords = melanocytic (Clic here for more details about this article) |
8/61. Cytology of melanotic schwannoma in a fine needle aspirate and pleural fluid. A case report.BACKGROUND: Melanotic schwannoma (MS) is a rare pigmented neural tumor most commonly occurring in the paraspinal region and involving spinal nerve roots and sympathetic ganglia. Few case reports describe the fine needle aspiration (FNA) cytology of MS. We report an additional case and for the first time describe the cytologic findings of MS in pleural fluid. CASE: A 44-year-old man presented with a 9.0-cm paraspinal mass associated with multiple lung nodules. FNA cytology of the paraspinal mass showed solitary and syncytially arranged spindled cells, with prominent nucleoli and variable amounts of cytoplasmic brown pigment. In pleural fluid, prominent isolated single cells were rounded and had a signet ring cell morphology. Tumor cells in both the aspirate and pleural fluid expressed S-100 protein and HMB-45. CONCLUSION: The FNA cytology findings of MS correlate well with the histologic findings. In pleural fluid, however, the cells are epithelioid, and some have a signet ring morphology, mimicking adenocarcinoma.- - - - - - - - - - ranking = 1keywords = pigmented (Clic here for more details about this article) |
9/61. Primary pigmented malignant schwannoma in the posterior mediastinum.This paper describes a rare case of primary pigmented malignant schwannoma arising from the sympathetic trunk in the posterior mediastinum. A 30-year-old woman underwent a thoracoscopic tumor extirpation. A primary pigmented malignant schwannoma was diagnosed histologically. The tumor presented fascicles and whorls of pigmented plump spindle cells and positive immunoreactivity to S-100 protein, vimentin, and HMB-45. Postoperative radiotherapy of the mediastinum was performed. Our case demonstrates the successful thoracoscopic resection and postoperative radiation treatment of a malignant schwannoma.- - - - - - - - - - ranking = 7keywords = pigmented (Clic here for more details about this article) |
10/61. A primary tumour of the oesophagus with both melanocytic and schwannian differentiation. Melanocytic schwannoma or malignant melanoma?A 76 year old white woman presented with a four month history of dysphagia and weight loss. Clinical, radiological, and endoscopic examination revealed a pigmented mass in the lower third of the oesophagus. The preoperative diagnosis, including biopsy examination, was that of malignant melanoma. Following oesophageal resection, the mass was found to be a localised, relatively superficial tumour with light, electron microscopic, and immunohistochemical features common to both schwann cells and melanocytes. The patient survived 46 months after surgery and died of a stroke, with no evidence of tumour recurrence. The tumour is presented as a case of melanocytic schwannoma, with unique features when compared with oesophageal melanotic schwannomas and malignant melanomas described in the literature. The differential diagnosis is discussed and an origin from a common precursor cell of neural crest origin is postulated.- - - - - - - - - - ranking = 48.669506251626keywords = melanocytic, pigmented (Clic here for more details about this article) |
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