Hemangiopericitoma com metástase craniana; relato de caso e análise de literatura / Hemangiopericytoma associated with cranial metastasis; a case report and analysis of the literature

Hemangiopericitomas säo tumores derivados dos pericitos - células presentes nas paredes dos capilares normais - e podem acometer todo o organismo. Quando intracranianos, provêm das meninges e säo considerados raros nessa localizaçäo. Apesar de alguns autores ainda o considerarem variante angioblástica do nemingeoma, o consenso da literatura, baseada em estudos imuno-histoquímicos e ultra-estruturais, é de que se trata de entidade distinta. Pela raridade em nosso meio é apresentado um caso de hemangiopericitoma clavicular com metástase craniana, e discutem-se os aspectos neuro-radiológicos e histopatológicos, relacionados à literatura mundial. Em nossa opiniäo, o hemangiopericitoma é uma entidade distinta. O estudo angiográfico mostrou-se mais útil que o estudo por tomografia computadorizada, permitindo o diagnóstico pré-operatório e auxiliando no planejamento cirúrgico. A ressecçäo desses tumores, invasivos e com alta taxa de metastatizaçäo e reincidência, deve ser total, näo havendo ainda consenso sobre o valor da complementaçäo radioterápica

Meningioma, meningeal hemangiopericytoma (angioblastic meningioma), peripheral hemangiopericytoma, and acoustic schwannoma. A comparative immunohistochemical study.

The relationship between meningeal hemangiopericytoma (angioblastic meningioma), meningiomas of meningothelial derivation, and peripheral hemangiopericytoma is controversial; and immunohistochemical studies have yielded conflicting results. Likewise, immunohistochemistry has been touted as a reliable means of differentiating fibrous meningioma from acoustic schwannoma. By the immunoperoxidase method, we studied 40 meningiomas (11 meningotheliomatous, four transitional, 11 fibrous, three secretory, four metaplastic, one xanthomatous, one papillary, four atypical, one malignant), five arachnoid granulations, 13 angioblastic meningiomas, nine peripheral hemangiopericytomas, and seven acoustic schwannomas. Antisera to vimentin, epithelial membrane antigen (EMA), keratin, S-100 protein, carcinoembryonic antigen (CEA), desmin, factor VIII, Ulex europeaus, and glial fibrillary acidic protein (GFAP) were utilized. All meningiomas and arachnoid granulations stained for vimentin and EMA; 15% and 12% of meningiomas were S-100 and keratin positive, respectively. The latter was noted primarily in areas of secretory (pseudopsammomatous) differentiation. In contrast, all angioblastic meningiomas stained for only vimentin. This profile of immunoreactivity was also seen in the peripheral hemangiopericytomas, with the exception of single cases that stained focally for EMA and S-100 protein, respectively. Acoustic schwannomas all stained positively for S-100 protein, vimentin, and were variably reactive for EMA, a pattern not distinct from meningioma. We conclude that (a) meningiomas express both epithelial and mesenchymal markers as do arachnoid granulations, (b) that angioblastic meningiomas demonstrate only mesenchymal markers, (c) that angioblastic meningiomas express identical markers to peripheral hemangiopericytoma and should thus be considered a variant thereof, (d) among meningiomas, CEA and keratin appear to be relatively specific markers for the "secretory" variant, and (e) because of overlap in S-100 and EMA reactivity, these markers are unreliable in differentiating meningioma from acoustic schwannoma.

[Malignant peripheral neuroectodermal tumors. Histological and immunohistological conditions in 41 cases]. / Maligne periphere neuroektodermale Tumoren. Histologische und immunohistochemische Befunde an 41 Fällen.

In view of the personal observation that malignant peripheral neuroectodermal tumours (MPNT) can present different histological growth patterns, 41 cases of MPNT were histologically and immunohistochemically studied. The median age of the 41 patients was 15 years (range: 9 months - 23 years). There were 27 males and 14 females. Most tumours (23/41) were located in the thoracopulmonary region. In 31/41 cases there was bone as well as soft tissue involvement. The following histopathological patterns were found: Ewing's sarcoma-like (n = 7), atypical Ewing's sarcoma-like (n = 4), neuroblastoma-like (n = 8), rhabdomyosarcoma-like (n = 8), and hemangiopericytoma-like (n = 1). In 2 cases combined patterns were noted, one tumour being characterized by neuroblastoma-like and Burkitt's lymphoma-like features. Most cases of MPNT differed from the cytological features of typical Ewing's sarcoma in that they contained hyperchromatic nuclei with distinct nucleoli. Some reticulin fibrils were found in between the cells of some cases. Immunohistochemically, 19/23 cases reacted positively to vimentin, 29/32 to neuron specific enolase (NSE), 16/28 to protein S-100, and 1/9 to glial fibrillary acidic protein. 12/24 cases reacted positively to NSE and protein S-100. Neurofilaments and desmin were not found in the formalin fixed material of the present study. The results show that most cases of MPNT can be distinguished from typical Ewing's sarcoma by cytological and histological findings. Differential diagnosis from atypical Ewing's sarcoma, neuroblastoma, and rhabdomyosarcoma is possible by immunohistochemistry.

Immunohistochemical characteristics of haemangiopericytic meningiomas: comparison with typical meningiomas, haemangioblastomas and haemangiopericytomas from extracranial sites.

The relationship between malignant vascular meningeal tumours and typical meningiomas remains controversial, despite the need for accurate diagnostic distinction between the two, and some forms of vascular meningioma may be more closely allied to haemangioblastomas or extracranial haemangiopericytomas than to true meningiomas. In order to try to clarify the diagnostic characteristics and origins of the entity known as haemangiopericytic meningioma, 10 histologically typical cases were stained by the immunoperoxidase technique with a panel of seven antibodies. The results were compared with those obtained from typical and angiomatous meningiomas, haemangioblastomas and haemangiopericytomas from extracranial sites. Both the haemangiopericytic meningiomas and the extracranial haemangiopericytomas showed a similar staining pattern, which differed from that of the typical and angiomatous meningiomas in the strikingly focal nature of the vimentin staining and the lack of reactivity with antibodies to epithelial elements. The haemangioblastomas were less consistent in their individual staining characteristics, but had a quite different overall pattern from all the other tumour types. It is, therefore, suggested that so-called haemangiopericytic meningiomas are in fact primary haemangiopericytomas of the meninges, antigenically distinct from true meningiomas and displaying a malignant potential appropriate to haemangiopericytomas arising in any other sites.

Acromegaly associated with suprasellar and pulmonary hemangiopericytomas. Case report.

The authors report the case of a 35-year-old acromegalic woman who developed amenorrhea and decreased left vision, and who was found to have suprasellar and pulmonary hemangiopericytomas. Total removal of the suprasellar hemangiopericytoma resulted in normalization of the plasma human growth hormone (GH) level and a marked decrease in size of the pulmonary hemangiopericytoma. Immunoperoxidase studies for GH and human hypothalamic growth hormone-releasing factor (GHRF) demonstrated immunoreactive intracellular GH only in the suprasellar hemangiopericytoma, with no immunoreactive intracellular GHRF evident in either the suprasellar or pulmonary hemangiopericytoma.

Distribution of endothelial and basement membrane markers in angiogenic tumors of the nervous system.

The distribution of two endothelial cell markers Factor-VIII-related antigen and Ulex europaeus agglutinin was examined by immunoperoxidase and immunofluorescence techniques in paraffin-embedded specimens representing the three main types of angiogenic neoplasms of the nervous system, hemangioblastoma, hemangioendothelioma and hemangiopericytoma. In addition, the distribution of the basement membrane (BM) marker, laminin, was studied in the same tumors. It was found that Ulex europaeus agglutinin was a more sensitive marker of neoplastic endothelial cells than Factor-VIII-related antigen. Both markers only stained endothelial cells, while the tumor cells of hemangiopericytomas and the stromal cells of hemangioblastomas remained unstained. These findings do not support the view that the stromal cells of hemangioblastomas are derived from endothelial cells. With antiserum to laminin a typical staining pattern could be noticed in each tumor, showing the architectural relationships of the cells very clearly. In all three tumor types laminin was only found in the BM of the vessels, not in the interstices of the neoplastic cells outside vessel lumina. Therefore, the reticulin network previously found between the individual cells of hemangiopericytomas does not correspond to BM. It is concluded that both Ulex europaeus agglutinin and laminin antisera could be valuable new aids for the diagnosis of the three tumor types.

Retroperitoneal hemangiopericytoma associated with hypoglycemia: report of a case.

A 34-year-old woman had episodes of hypoglycemic attack 8 years after a surgical resection of a retroperitoneal hemangiopericytoma. In spite of normal levels of serum IRI, insulin radioreceptor assay demonstrated high level of plasma ILA (insulin like activity). The patient underwent resection of a recurrent retroperitoneal tumor with metastatic lesions of the liver. Postoperatively, ILA level in plasma by insulin radioreceptor assay decreased, and hypoglycemic attacks disappeared. Therefore, this associated hypoglycemia was presumed to be not caused by excess glucose consumption by the tumor, not by excess secretion of IRI by the tumor, but caused by the presence of high level of ILA related to the tumor.