1/10. Malignant peripheral nerve sheath tumour in the maxilla associated with von Recklinghausen's disease.Malignant transformation of neurofibromatosis is one of the most serious complications of von Recklinghausen's disease (VRD). The most common associated malignancy is the malignant peripheral nerve sheath tumour (MPNST). Few cases of MPNST associated with VRD in the maxillary region have been reported. This report describes a rare case of MPNST in the maxilla and the aggressive nature of MPNST associated with VRD.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
2/10. carcinosarcoma of the urinary bladder--an aggressive tumor with diverse histogenesis. A clinicopathologic study of 4 cases and review of the literature.OBJECTIVE: Carcinosarcomas of urinary bladder are rare malignant neoplasms. Seventy-eight cases have been previously described. The histologic composition of these tumors is variable, but diagnosis requires the presence of both epithelial and mesenchymal malignant components. We report 4 additional cases, with an emphasis on unusual histologic features. methods: Histologic and immunohistochemical examinations were performed on bladder tumors from 4 patients. Clinicopathologic features of previously reported and current cases were reviewed and summarized. RESULTS: Four patients (3 men, 1 woman) age 54 to 77 years were found to have polypoid masses in the urinary bladder. In all cases, histologic examination showed biphasic neoplasms with distinct mesenchymal and epithelial components. The morphologic and immunohistochemical characteristics of the tumors varied. One of the cases was remarkable for the presence of liposarcoma, malignant peripheral nerve sheath tumor, and micropapillary urothelial carcinoma. Two of the patients died 2 years after diagnosis, which is consistent with the previously reported aggressive nature of urinary bladder carcinosarcomas. CONCLUSIONS: Carcinosarcomas of the urinary bladder are rare, aggressive malignant neoplasms. To our knowledge, a liposarcomatous component has been reported in only 1 case previously, and components of micropapillary urothelial carcinoma and malignant peripheral nerve sheath tumor have not been reported previously in carcinosarcomas of the urinary bladder. Because of the aggressive biologic behavior of these tumors, they should be identified promptly and treated appropriately.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
3/10. Multiple recurrences in malignant peripheral nerve sheath tumor of the orbit: a case report and a review of the literature.PURPOSE: To report the onset of malignant peripheral nerve sheath tumor of the orbit 8 years after irradiation in a patient with neurofibromatosis type-1. methods: Case report of a young man with neurofibromatosis type-1 who received irradiation for presumed bilateral optic nerve and chiasmal gliomas and in whom a malignant peripheral nerve sheath tumor later developed. Exenteration with extirpation of the entire contents of the orbit was performed 6 times. RESULTS: Complete recurrence of the tumor occurred after each surgical procedure until the patient died of malignancy. CONCLUSIONS: Our case underscores the risk of irradiation, especially in children with neurofibromatosis type-1, and emphasizes that radiotherapy should never be given as an empirical therapy. The authors believe that irradiation and neurofibromatosis type-1 may, in combination, pose a significant risk for the development of malignancies. Clear-cut indications and a precise tissue diagnosis are desirable before the initiation of radiotherapy, particularly in the pediatric population. We recommend that if irradiation is necessary in persons with neurofibromatosis type-1, regular follow-up is imperative. In view of the hostile nature of malignant peripheral nerve sheath tumor, early aggressive treatment appears to be the only viable alternative at present.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
4/10. Cutaneous sclerosing Pacinian-like perineurioma.AIMS: The term perineurioma has been used to designate a variety of clinically and histologically different proliferations of perineurial cells based on immunohistochemical and/or ultrastructural characterization. There are two different groups of neoplasms derived from perineurial cells: extraneural or soft tissue perineuriomas, and intraneural perineuriomas. Recently, a sclerosing variant of cutaneous perineurioma has been described. methods AND RESULTS: We report a case of a cutaneous form of perineurioma, combining features of the intraneural and sclerosing varieties, as well as showing a Pacinian pattern of growth. In order to assess the neoplastic nature of the lesion, we performed fluorescence in-situ hybridization (FISH) analysis using a probe which maps to the chromosome band 22q11 and 22q13, allowing us to show deletion or loss of one chromosome 22 in the tumour cells. CONCLUSIONS: This case may be considered a new variant of perineurioma with Pacinian-like features, for which we propose the designation 'sclerosing Pacinian-like perineurioma'.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
5/10. Intraosseous intraneural perineurioma: report of a case with morphological, immunohistochemical and FISH study.We report a case of an intramandibular intraneural perineurioma developed in the left dentary nerve. This tumour is rare and shows a typical histological, immunohistochemical and ultrastructural appearance: concentric whorls of perineurial cells EMA and PS100- around nerve fibers. This tumour must be distinguished from extraneural or soft tissue perineurioma, also composed of perineurial cells, with distinct clinical presentation and histological appearance, and from localized hypertrophic neuropathy, a reactive process frequently identified with intraneural perineurioma. Cytogenetic evidence for the neoplastic nature of this tumour is also presented in this report.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
6/10. Cellular schwannoma: a rare spinal benign nerve-sheath tumor with a pseudosarcomatous appearance: case report.We report a case of cellular schwannoma, a rare benign nerve-sheath tumor in a 27 year-old woman. It was presented as a voluminous lesion in the paraspinal region that caused lumbar vertebral body destruction. These features, in association to the microscopic aspects of a hypercellular, pleomorphic neoplasm may lead to a false impression of a malignant tumor. Therefore, it is important to have an accurate examination to confirm the benign nature of this tumor thus avoiding unnecessary therapy.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
7/10. Multiple brain metastases from malignant peripheral nerve sheath tumour (MPNST).Malignant peripheral nerve sheath tumours (MPNSTs) are rare soft tissue neoplasms arising from elements of the nerve sheath that often occur in the context of neurofibromatosis (NF) type 1. Their poor prognosis results from high local recurrence rate and distant dissemination. Nevertheless, the brain metastases are exceptional. We are presenting an unusual case of intrathoracic MPNST in a 33-year-old man with a five-year clinical course characterised by multiple times local recurrences of primary tumour and multiple remote metastases into the brain structures, thyroid and suprarenal gland. Moreover, the cerebellar metastasis regrew in spite of its total excision. Histologically, brain metastatic tumours were composed of spindle cells closely arranged in interlacing and woven fascicles. This highly cellular nerve tissue exhibited an advanced nuclear hyperchromasia and a high mitotic activity. The tumour exhibited rich delicate reticulin network. The schwannian nature of brain metastases has been confirmed by immunohistochemical findings showing S-100 protein and GFAP expression and ultrastructural evidences of the pericellular basal lamina.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
8/10. Bilateral intraneural perineurioma presenting as ulnar neuropathy at the elbow.We describe a 36-year-old woman with progressive bilateral ulnar neuropathy. Sonographic and magnetic resonance imaging studies revealed extensive focal ulnar nerve enlargement at the elbow. Histological studies gave evidence of an intraneural perineurioma. Because intraneural perineurioma usually appears as a single mass lesion at sites other than typical entrapment sites, this mode of presentation is unusual. We discuss the nature of this benign tumor and the differential diagnosis of nerve enlargement. knowledge of possible causes of nerve thickening is crucial when performing imaging in patients with neuropathies.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
9/10. A 71-year-old man with spindle-cell neoplasm of unknown origin: a difficult-to-diagnose clear-cell sarcoma.A patient initially presented in 1988 with a solitary axillary mass, diagnosed as a high-grade neuroendocrine spindle-cell neoplasm; there was no history of a primary cutaneous malignancy. After subsequent development of a pulmonary nodule in 2001 (14-years post initial diagnosis), the case was reviewed and the possibility of metastatic melanoma was raised. The histopathologic and immunohistochemical profile of this melanocytic neoplasm was diagnostic of clear cell sarcoma (CCS) of tendons and aponeuroses, although the differential diagnosis included malignant melanoma, follicular dendritic and interdigitating cell tumors, malignant peripheral nerve sheath tumor, and a category of so-called PEComas. It is the role of pathologists, particularly dermatopathologists, to distinguish CCS from malignant melanoma, and to alert the clinician, because proper diagnosis ultimately influences treatment. We discuss the immunophenotype, differential diagnosis, and molecular signatures of these neoplasms, and review the pertinent literature on these entities.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
10/10. Malignant intraosseous peripheral nerve sheath tumour of the proximal femur: a case report.We report a rare case of an intraosseous malignant peripheral nerve sheath tumour of the femoral head and neck. The tumour presented as a well-defined radiolucent lesion on plain radiography. Computed tomography showed aggressive destruction of the bone with no involvement of the adjacent soft tissues. magnetic resonance imaging revealed an isointense signal intensity on T1-weighted images, hyperintensity on T2-weighted images, and non-homogeneously increased signal intensity after administration of contrast media. The final diagnosis was based on pathohistologic analyses due to the non-specific nature of the lesion.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
| | Next -> |