Immunohistochemical diagnosis of a rare case of epithelioid malignant peripheral nerve sheath tumor with multiple metastases
ABSTRACT The epithelioid variant of malignant peripheral nerve sheath tumor (MPNST) is a rare tumor with poor prognosis that sometimes involves the head and neck. The diagnosis is based principally on the histological examination, and it is generally very difficult to reach the correct diagnosis.
An 84-year-old Japanese woman presented with a tumor mass of 2 week's duration in the right medial canthal region.
Although the tumor was excised surgically, metastases occurred three times on her face and head, and the patient died of distant systemic multiple metastases. In the histopathological analysis, the tumor showed a composite pattern comprising spindle or polygonal cells arranged in irregular bands, and a population of larger epithelioid cells in solid sheets and nests. In the immunohistochemical analysis, the tumor cells were positive for S-100 protein, vimentin, and nerve growth factor receptor (NGFR), and negative for cytokeratin and HMB 45 (melanoma-associated antigen). These findings confirmed the diagnosis of MPNST.
Epithelioid MPNST has complex histopathological findings and histopathological features similar to other epithelioid tumors, especially malignant melanoma. Immunohistochemical examination using NGFR and HMB-45 is important in the differential diagnosis.
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ABSTRACT: The malignant schwannoma is a neoplasia whose origin is given by peripheral nerve tissue. It rarely appears in the head and neck, and even less frequently in maxillofacial territory. Here is a case report of a male patient, 9 years old, with a rapidly growing mass, expansive growth, located in the body and right mandibular ramus diagnosed as a malignant neurosarcoma or malignant schwannoma of the mandible, with mandibular canal, mental canal and foramen, soft tissue and bone involvement of the region.
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ABSTRACT: Stardust is a mission to fly by Comet Wild-2 in early 2004 and return samples of the coma to Earth. During its 120-150 km flyby of the comet nucleus, a secondary science goal is to obtain images of the nucleus using the onboard navigation camera. Due to the 40 minute round-trip light time, ground processing of navigation data to update pointing information to maintain the nucleus in the camera field-of-view is impractical. Thus, a simple, reliable, and fast algorithm was developed to close the navigation loop onboard during encounter. The algorithm uses images of the nucleus during approach to update target relative state information. This involves centroiding on the image to obtain nucleus center-of-figure data and then processing the data through a Kalman filter to update the spacecraft, position and attitude. Monte Carlo simulations were then performed to test the algorithm. These simulations incorporated errors in spacecraft initial position and in attitude knowledge to provide a “truth” model which the filter must recover from. The results of the simulations proved that the algorithm was successful in maintaining the nucleus in the camera field-of-view assuming nominal values for the error sources. Even with worst case errors, the algorithm performed successfully in over 90% of the casesAerospace Conference, 1998 IEEE; 04/1998
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ABSTRACT: Malignant peripheral nerve sheath tumors are rare tumor entities that originate from peripheral nerve sheaths and have an unfavorable prognosis. Metastatic spread to the cerebral parenchyma is absolutely rare. This case report describes the clinical course in a 60-year-old man whose tumor came to medical attention because of a seizure. Magnetic resonance imaging demonstrated two intracerebral lesions. The symptomatic lesion was removed microneurosurgically and histology demonstrated a metastasis from a malignant peripheral nerve sheath tumor. Postoperatively, whole-brain irradiation was performed. The primary tumor was identified in the area of the sciatic nerve on the right. Follow-up 14 months after resection showed that there was no progression of the intracerebral lesions but an increase in size and number of distant metastases. There are no generally accepted guidelines for the treatment of malignant peripheral nerve sheath tumors with cerebral metastases. This case report presents and discusses one possible therapeutic approach. Due to the poor overall prognosis, the least invasive therapy should be chosen.BMC Neurology 02/2007; 7:2. DOI:10.1186/1471-2377-7-2 · 2.04 Impact Factor