Malignant peripheral nerve sheath tumor

About: Malignant peripheral nerve sheath tumor is a research topic. Over the lifetime, 1814 publications have been published within this topic receiving 36187 citations. The topic is also known as: malignant neoplasm of the peripheral nerve Sheath & malignant peripheral nerve sheath tumor (disorder).

Malignant peripheral nerve sheath tumors. A clinicopathologic study of 120 cases.

Abstract: A review was done of 120 cases of malignant peripheral nerve sheath tumor (MPNST) seen during a 71-year period. Of the 120 patients, 52 were males and 68 were females with a mean age at diagnosis of 35.3 years; 12 patients were younger than 20 years. The series included 62 (52%) patients with neurofibromatosis, 13 (11%) with postradiation sarcomas, and 19 (16%) with metaplastic foci. The incidence of MPNST arising in neurofibromatosis was 4.6% in the current series and 0.001% in the general clinic population. Tumors greater than 5 cm and the presence of neurofibromatosis adversely affected the prognosis (P less than 0.05). When both features were present, survival was greatly decreased. Patients with tumor in the extremities did better than those with head or neck lesions. Metaplastic foci or previous radiation at the tumor site did not alter the prognosis. Each tumor was graded 1 to 4 on the basis of cellularity, pleomorphism, mitotic index, and necrosis. No significant correlation was noted between survival and either grade or mitotic rate. Survival was improved when total rather than subtotal resection was done. This was most marked in patients with a small lesion, which may reflect the difficulty in adequately excising large tumors. Adjuvant radiation or chemotherapy did not appear to affect survival. The MPNST is an aggressive uncommon neoplasm, and large tumor size, the presence of neurofibromatosis, and total resection are the most important prognostic indicators.

Malignant peripheral nerve sheath tumours in neurofibromatosis 1

Abstract: Background: Cross sectional studies have shown that 1-2% of patients with neurofibromatosis 1 (NF1) develop malignant peripheral nerve sheath tumours (MPNST). However, no population based longitudinal studies have assessed lifetime risk. Methods: NF1 patients with MPNST were ascertained from two sources for our north west England population of 4.1 million in the 13 year period 1984-1996: the North West Regional NF1 Register and review of notes of patients with MPNST in the North West Regional Cancer Registry. Results: Twenty-one NF1 patients developed MPNST, equivalent to an annual incidence of 1.6 per 1000 and a lifetime risk of 8-13%. There were 37 patients with sporadic MPNST. The median age at diagnosis of MPNST in NF1 patients was 26 years, compared to 62 years in patients with sporadic MPNST (p Conclusion: The lifetime risk of MPNST in NF1 is much higher than previously estimated and warrants careful surveillance and a low threshold for investigation.

Histological Typing of Tumours of the Central Nervous System

Abstract: Introduction Histological Classification of CNS Tumours Definitions and Explanatory Notes Tumours of Neuroepithelial Tissue Astrocytic Tumours Ependymal Tumours Mixed Gliomas Choroid Plexus Tumours Neuroepithelial Tumours of Uncertain Origin Neuronal and Mixed Neuronal-Glial Tumours Pineal Parenchymal Tumours Embryonal Tumours Tumours of Cranial and Spinal Nerves Schwannoma Neurofibroma Malignant Peripheral Nerve Sheath Tumor Tumours of the Meninges Tumours of Menigothelial Cells Mesenchymal, Non-menigothelial Tumours Primary Melanocytic Lesions Lymphomas and Haemopoietic Neoplasms Germ Cell Tumours Cysts and Tumour-like Lesions Tumours of the Sellar Region Local Extensions from Regional Tumours Metastatic Tumours Unclassified Tumours Illustrations Subject Index Metat Cy Tu

Neurofibromatosis type 1 revisited.

Abstract: Neurofibromatosis type 1 (NF1) is an autosomal dominant condition with a worldwide incidence of 1 per 2500 to 3000 individuals. Caused by a germ-line‐ inactivating mutation in the NF1 gene on chromosome 17, the disease is associated with increased morbidity and mortality. In the past several years, significant progress has been made in standardizing management of the major clinical features of neurofibromatosis type 1. Moreover, improved understanding of how the neurofibromatosis type 1 protein, neurofibromin, regulates cell growth recently provided insight into the pathogenesis of the disease and has led to the development of new therapies. In this review, we describe the clinical manifestations, recent molecular and genetic findings, and current and developing therapies for managing clinical problems associated with neurofibromatosis type 1. Pediatrics 2009;123:124‐133

"Proximal-type" epithelioid sarcoma, a distinctive aggressive neoplasm showing rhabdoid features. Clinicopathologic, immunohistochemical, and ultrastructural study of a series

Abstract: Eighteen examples of an unusual malignant soft-tissue neoplasm, the morphology of which ranged from that of "atypical" epithelioid sarcoma to that of a rhabdoid tumor or undifferentiated carcinoma (with transitional forms) are described. Patients included 11 males and seven females; their median age was 35.5 years with most patients aged 20 to 40 years. Development of a mass was the main presenting symptom. Six tumors developed in the pelvis and perineal region, four in the pubic region and vulva, three in the buttocks, one in the deep soft tissues of the left hip, one on the penis, one in left forearm, one in left axilla, and one on the occiput. Tumor size ranged from 1 to 20 cm (median, 4 cm). On microscopic examination, the tumor cells invaded the subcutaneous or deep soft tissues, had prominent epithelioid or rhabdoid features, had marked cytologic atypia, and grew in a multinodular pattern in half of the cases. Areas of necrosis were often seen. A granuloma-like pattern reminiscent of that observed in classic epithelioid sarcoma was observed in only two cases. Immunohistochemically, positivity for cytokeratin, epithelial membrane antigen, and vimentin was seen in all but one of the cases. Of 16 cases, 10 and eight tumors reacted with desmin and CD34, respectively; five of 15 reacted at least focally with smooth-muscle actin, whereas three of 13 and one of 10 reacted for HMB-45 and carcinoembryonic antigen, respectively. S-100 protein and CD31 yielded negative results. Seven tumors were investigated at the ultrastructural level, four of which showed prominent intracytoplasmic intermediate filament aggregates, often accumulating into paranuclear whorls, which is in keeping with the rhabdoid phenotype. Five tumors showed features of epithelial differentiation (i.e., tonofilament-like structures or desmosomes or both), whereas one tumor displayed features of myofibroblastic differentiation. Differential diagnoses include mainly conventional epithelioid sarcoma, extrarenal malignant rhabdoid tumor, epithelioid malignant peripheral nerve sheath tumor, melanoma, rhabdomyosarcoma, and undifferentiated carcinoma. Follow-up information on 14 patients (range, 4 months to 8 years; median, 19 months) revealed local recurrence in one case and metastatic dissemination in six patients, leading to death in five. In our opinion, the above-described neoplasms represent a usually "proximal-type" of epithelioid sarcoma. In contrast to the conventional, "distal-type" epithelioid sarcoma, the proximal variant is characterized by a predominantly large-cell, epithelioid cytomorphology, marked cytologic atypia, frequent occurrence of rhabdoid features, and lack of a granuloma-like pattern in most cases. It appears to be somewhat more aggressive (or at least metastasizes earlier) than usual epithelioid sarcoma.