Hemangioendothelioma originating in a peripheral nerve; report of a case

Synovial Sarcoma of Peripheral Nerves: Analysis of 15 Cases

Synovial sarcoma of peripheral nerve (SSPN) is rare with only 26 cases reported in English. SSPN is often mistaken for a benign or malignant peripheral nerve sheath tumor (PNST) by clinicians and pathologists. Fifteen cases of SSPN were retrieved from the pathology files of 3 institutions. All tumors arose in a nerve based on imaging and/or operative findings and the diagnoses were histologically confirmed. Neuropathic symptoms predominated in 11 women and 4 men, 19- to 62-year-old (median, 39 years) with tumors involving the ulnar (5), median (3), peroneal (3) or sciatic (2) nerve, or the L4 or T1 nerve root (2). Tumor sizes ranged from 2 to 13 cm (median, 3.8 cm). The leading clinical diagnosis was PNST (9). Treatment was surgical (14) supplemented with radiation therapy (8) and chemotherapy (6). Fourteen tumors were monophasic and 1 was biphasic; 4 had poorly differentiated (PD) foci (1 rhabdoid). Diagnoses in 12 cases were verified by fluorescence in situ hybridization, reverse transcription polymerase chain reaction or both methods. Follow-up in 14 patients (median, 32 mo) revealed that 2/4 patients with PD tumors died with pulmonary metastases; another was alive with no current evidence of disease (NED) following 2 local recurrences, while the fourth had NED. In contrast, 9/10 patients without PD tumors were alive (7 NED) and 1 died at 12 months with pulmonary infiltrates. SSPN is under-recognized clinically and histologically as it mimics benign and malignant PNST. Molecular analysis is recommended to confirm the diagnosis. PD foci, including rhabdoid areas, may portend a worse outcome, similar to non-neural-based tumors.

Intraneural angiosarcoma and angiosarcoma arising in benign and malignant peripheral nerve sheath tumours: clinicopathological and immunohistochemical analysis of four cases

AIMS

Angiosarcomatous differentiation represents the least common form of heterologous differentiation in malignant peripheral nerve sheath tumours (MPNST), and is seen most frequently in patients with neurofibromatosis type 1. More rarely, it has been reported in patients without stigmata of neurofibromatosis, or in benign nerve sheath tumours and peripheral nerves. This study was undertaken to confirm this rare association.

METHODS AND RESULTS

Four cases of angiosarcoma arising in a peripheral nerve, in a long-standing schwannoma and in two MPNST are described. Immunohistochemical studies were performed on paraffin sections with the alkaline phosphatase-antialkaline phosphatase method. An intraneural high-grade epithelioid angiosarcoma arose in the left posterior tibial nerve of a 78-year-old man, a well to moderately differentiated angiosarcoma was seen in an ancient schwannoma of the lateral neck in a 73-year-old women, and an angiosarcoma of varying grades of differentiation developed in a recurrent MPNST in the thigh of 38-year-old man. In addition a high-grade MPNST in the axillary region of a 30-year-old man showed foci of heterologous high-grade angiosarcomatous differentiation. The neural and endothelial lines of differentiation were confirmed in each case by positive immunohistochemical staining for neural and endothelial markers, respectively. In all cases tested, the neural differentiated cells stained immunohistochemically positive for antibodies against vascular endothelial growth factor.

CONCLUSIONS

This study confirms the rare association of angiosarcoma arising in peripheral nerves, as well as in benign and malignant peripheral nerve sheath tumours.

Angiosarcoma arising in a solitary schwannoma (neurilemoma) of the sciatic nerve

Angiosarcomas rarely develop within a peripheral nerve or a peripheral nerve sheath tumor. We describe an epithelioid angiosarcoma that arose in a benign schwannoma (neurilemoma) of the right thigh in a 65-year-old man who did not have von Recklinghausen's disease. Histologically, the resected tumor was a high-grade undifferentiated sarcoma that was predominantly arranged in solid sheets or nests and composed of epithelioid cells. The endothelial origin of the tumor was suggested by Factor VIII R-ag, Ulex europaeus-I, CD34, CD31, BNH9, and vimentin immunoreactivity, along with the ultrastructural evidence of occasional Weibel-Palade bodies. In this location, epithelioid angiosarcoma should be distinguished from malignant transformation of a schwannoma with epithelioid changes. This observation stresses the importance of immunohistochemical and ultrastructural analysis in the differential diagnosis of vascular tumors with features of epithelioid sarcoma.

Hemangiopericytoma of the sciatic nerve. Case report

The authors report the case of a hemangiopericytoma arising in a sciatic nerve. It was found to be invasive within the epineurium but sparing surrounding tissues. Adequate resection required sacrifice of the nerve. Hemangiopericytomas can be added to the short list of mesodermal peripheral-nerve tumors.

Hepatic neurofibromatosis, malignant schwannoma, and angiosarcoma in von Recklinghausen's disease

Liver involvement by neurofibromatosis is rare. This report describes a young man with von Recklinghausen's disease and hepatic neurofibromas who developed a large right hepatic lobe malignancy and died of massive intratumor hemorrhage. Postmortem examination showed the tumor to be composed of both malignant schwannoma and angiosarcoma and to have arisen from contiguous neurofibromas in portal tracts. Widespread pulmonary metastases consisted of the angiosarcomatous elements alone. The expression of malignant schwannoma and angiosarcoma phenotypes in this tumor may be related to a common histogenesis from cells of the neural crest.

The pathophysiology of neurofibromatosis. II. Angiosarcoma as a complication

A patient with Von Recklinghausen neurofibromatosis and an angiosarcoma (which developed subsequent to two separate neurofibrosarcomas ) is described, and the association of neurofibromatosis and angiosarcoma is reviewed. The data showed that angiosarcoma is not coincidental with neurofibromatosis, and there is a need to focus investigative efforts on the vascular aspects of this disease.

Angiosarcoma developing in a patient with Neurofibromatosis (von Recklinghausen's disease)

The authors present an angiosarcoma of the scrotum and penis. The disease occurred in a 61-year-old man with a long history of neurofibromatosis (von Recklinghausen's disease). The histologic and ultrastructural features are described. The authors speculate that the angiosarcoma, which developed in a location without histologic evidence of neurofibromatosis, possibly represents an expression of an abnormal genome in vascular tissue. The angiosarcoma responded to radiation therapy only temporarily, recurred after surgery, and did not respond to Adriamycin, dactinomycin or cis-platinum. The patient died three years after the onset of his angiosarcoma.

Combined neurilemmoma and angioma. Tumor of ectomesenchyme and a source of bleeding

Eight cases are described of intracranial and peripheral neoplasms composed of mixed neurilemmoma and hemangioma. It is proposed that ectomesenchyme can differentiate into neurilemmoma and angioma. The latter may be related to recently described angiogenetic factors, or to developmental factors as in rare cases of arterial angiomas. The angiomatous part may be common, but has often been overlooked. The presence of abnormal vessels, whether in kind or in number, helps explain various biological features of neurilemmoma. These vessels frequently bleed within the tumor, which results in the characteristic hemosiderin-laden macrophages. Bleeding may also occur into the cerebrospinal fluid (CSF) to create xanthochromia. The frequent increase in CSF protein in cases of neurilemmoma is attributed to transudation of serum from abnormal vessels. Less commonly, bleeding may be sufficient to cause subarachnoid hemorrhage. The dense collagen usually associated with these angiomas accounts for the relative infrequence of major hemorrhages.

Angiosarcoma of venous origin arising in radial nerve

A case of angiosarcoma felt to arise from a vein within the radial nerve is presented. Endovascular angiosarcoma arising in a vein is unusual and only one case of angiosarcoma in a peripheral nerve has been previously reported. Microsurgery followed by radiation has led to a 36-month tumor free survival.