Primary intracerebral malignant fibrous histiocytoma: immunohistochemical findings and etiopathogenetic considerations.

We report a case of malignant fibrous histiocytoma (MFH) arising as a second malignancy in a 13-year-old girl with a previous primitive neuroectodermal tumor of the cerebellum (medulloblastoma). The earlier tumor had been resected and treated with chemotherapy. Because of the age of the patient, no radiation therapy was used. The second neoplasm (an MFH), which presented almost 12 years later, was located within the left frontal region and had discrete meningeal attachment. Histologically, it showed the characteristic storiform pattern and pleomorphism of an MFH and displayed characteristic immunohistochemical reactivity. Careful clinical and radiologic investigation failed to reveal any other neoplasm in the body. This case is unique in that the MFH occurred in a young child after an earlier primary primitive neuroectodermal tumor, although at a distant site, and, importantly, without prior radiation therapy. In this report, we briefly review the literature with an emphasis on immunohistochemistry and histogenesis, raising the possibility that the MFH was induced by chemotherapy.

Oligodendrocytes produce low molecular weight glycoproteins containing N-acetyl-D-glucosamine in their Golgi apparatus.

Lectin histochemistry using the Griffonia simplicifolia II lectin (GSL II) has revealed a novel group of glycoproteins containing terminal N-acetyl-D-glucosamine (GlcNAc) residues in oligodendrocytes. The GlcNAc-containing glycoproteins were not present in other types of glial cells, but were expressed by some neuronal cell populations. Within oligodendrocytes their localization was confined to the Golgi apparatus, as determined ultrastructurally. Biochemical analyses using tricine/SDS-polyacrylamide gel electrophoresis and western blotting with GSL II showed the GlcNAc-containing glycoproteins to be insoluble, with molecular masses ranging from 15 to 30 kDa. Our study provides a first account of insoluble, GlcNAc-rich 15-30 kDa glycoproteins in oligodendroglia. The findings are discussed in the context of the functional significance of other known oligodendrocyte glycoproteins.

In situ detection of transforming growth factor-beta mRNA in experimental rat glioma and reactive glial cells.

Malignant gliomas are associated with a state of systemic immunosuppression which appears to be partially mediated by transforming growth factor beta (TGF-beta) secreted from glioma cells. In a recently described animal model of malignant glioma, massive activation of local microglial cells and formation of microglia-derived macrophages has been observed in the absence of detectable tumour regression. We have investigated the in situ expression of TGF-beta in rat glioma as a possible cause of ineffective tumour destruction. Two weeks following unilateral injection of glioma cells, large tumours were observed in the affected hemisphere. In situ hybridization for TGF-beta 1 mRNA revealed an intense signal over the entire tumour area. In the peritumoural area, at sites of glial activation, a lower signal was obtained over cellular profiles containing nuclei typical for microglia, as well as other unidentified cellular profiles. No signal was obtained over the contralateral unaffected hemisphere. Northern blot analysis revealed a strong expression of TGF-beta 1 mRNA in tumour tissue, a lesser signal in the peritumoural reactive brain tissue and virtually no signal in normal tissue. Our data indicate that the experimental rat glioma has the potential to secrete TGF-beta in vivo which might render the microglial infiltration ineffective. TGF-beta expressed by activated microglial cells themselves might further inhibit their tumoricidal potential, thus contributing further to unrestrained tumour growth.

Acute bilateral ophthalmoplegia secondary to cavernous sinus metastasis: a case report.

A case of a 60-year-old man with metastatic adenocarcinoma of the colon who developed bilateral ophthalmoplegia acutely is presented. Bilateral cavernous sinus metastasis was suggested by magnetic resonance imaging and proven by endoscopic sphenoidal biopsy. The patient was treated with radiotherapy (2000 cGy) with near resolution of his symptoms. This patient represents the first reported case of acute bilateral ophthalmoplegia resulting from hematogenous metastasis to both cavernous sinuses, diagnosed antemortem. A review of the more common causes of acute bilateral ophthalmoplegia is presented.

Lymphocytic hypophysitis: report of a case in a man with cavernous sinus involvement.

Lymphocytic hypophysitis (LH) is a rare inflammatory disease of the pituitary that produces hypopituitarism. It more commonly affects women during pregnancy or shortly after childbirth. Of the 34 reported cases only three have been males. We report the fourth known case of lymphocytic hypophysitis in a male who presented with hypopituitarism, diplopia, and cavernous sinus involvement. To our knowledge this is the second report of involvement of the cavernous sinus by LH. A comparative study of all four male cases is also presented. The findings reveal that the mean age at presentation in the male patients is 52.3, nearly 21 years older than that reported for female cases. Impotence with associated decrease in libido is the most common presenting symptom. Extraocular muscle palsy with associated infiltration of the cavernous sinus is an exclusive finding among male patients with LH. Concerning prognosis, none of the male patients regained pituitary function that had been lost at the time of presentation but required chronic replacement therapy.