Angiogenesis in normal and neoplastic pituitary tissues.

Angiogenesis, or the formation of new blood vessels, is a dynamic process needed for embryogenesis, post-natal growth, morphogenesis, tumorigenesis, and for other biological processes. Angiogenesis is very important for tumor development and progression. This review examines the activators and inhibitors of angiogenesis with emphasis on the pituitary gland and pituitary neoplasms.

Phase II trial of procarbazine, lomustine, and vincristine as initial therapy for patients with low-grade oligodendroglioma or oligoastrocytoma: efficacy and associations with chromosomal abnormalities.

Purpose: The purpose of this article is to determine the response rate and toxicity of PCV administered before radiation therapy in patients with newly diagnosed LGO/LGOA and to explore correlations between response with 1p/19q deletions and aberrant p53 expression.

Background: Despite prolonged survival of patients with low-grade oligodendroglioma (LGO) and oligoastrocytoma (LGOA), the majority will succumb to progressive disease. Because procarbazine, lomustine (CCNU), and vincristine (PCV) is active in patients with recurrent LGO/LGOA, we hypothesized that it would be beneficial as primary therapy.

Ancillary FISH analysis for 1p and 19q status: preliminary observations in 287 gliomas and oligodendroglioma mimics.

Deletions of chromosomes 1p and 19q are associated with chemosensitivity and enhanced survival in oligodendrogliomas. Therefore, we have utilized FISH analysis as an ancillary tool for diffuse gliomas with suspected oligodendroglial features. To date, 246 gliomas have been analyzed in 131 male and 93 female patients, including 109 oligodendrogliomas (O), 109 mixed oligoastrocytomas/equivocal gliomas (MOA), and 28 astrocytomas (A).

Growth factors and cytokines in paragangliomas and pheochromocytomas, with special reference to sustentacular cells.

The aim of this study was to localize various growth factors and cytokines in paragangliomas and pheochromocytomas in order to understand their possible autocrine or paracrine functions, and to compare sustentacular cells of the adrenal medulla with pituitary stellate cells. Thirteen resected tumors, 11 paragangliomas and 2 pheochromocytomas of the adrenal medulla, were studied. In addition, five surgically removed nontumorous adrenals and five nontumorous pituitaries were studied.

Oligodendrogliomas with neurocytic differentiation. A report of 4 cases with diagnostic and histogenetic implications.

Oligodendroglioma represents a distinct type of diffuse glioma with a relatively favorable prognosis. Although an O2A-like glial progenitor cell of origin has been suggested, a neuronal-oligodendroglial progenitor cell is also of interest, particularly because variable degrees of neuronal marker expression have been reported in typical oligodendrogliomas. We present 2 female and 2 male patients (ages 34-54) with frontal lobe oligodendrogliomas containing a) morphologically distinct collections of small round cells with hyperchromatic nuclei, b) well-formed Homer Wright-like and perivascular rosettes, and c) demonstrable neuronal differentiation by immunohistochemistry and/or electron microscopy in the rosette-associated regions.

Topoisomerase IIalpha expression in pituitary adenomas and carcinomas: relationship to tumor behavior.

DNA topoisomerase IIalpha (Topo IIalpha) is a molecular and immunohistochemical marker that indicates proliferation rate and is the target for several antineoplastic agents. The present immunohistochemical study of a large series of surgically removed pituitary tumors was designed to assess the prognostic significance of Topo IIalpha expression relative to patient age, gender, tumor type and size, invasiveness, metastasis, MIB-1-labeling index and angiogenesis. Changes of Topo IIalpha expression in the tumors treated with bromocriptine and octreotide, a long-acting somatostatin analogue were also investigated.

p53 in nonneoplastic central nervous system lesions: an immunohistochemical and genetic sequencing study.

Objective: Immunostaining for p53 commonly is considered a marker of neoplasia. Previous studies of nonneoplastic processes have yielded conflicting results.

Methods: To test the assumption that p53 immunoreactivity indicates neoplasia, we examined 60 formalin-fixed, paraffin-embedded biopsies of nonneoplastic central nervous system lesions, including gliosis (n = 12), infarction (n = 9), demyelinating disease (n = 23), progressive multifocal leukoencephalopathy (n = 11), and herpes simplex virus encephalitis (n = 5).

Microglia in brain tumors.

Microglia have long been ignored by neurooncologists. This has changed with the realization that microglial cells not only occur within and around brain tumors but also contribute significantly to the actual tumor mass, notably in astrocytic gliomas. In addition, it has been speculated that microglia could play a role in the defense against neoplasms of the nervous system.

Risk of cancer among relatives of patients with glioma.

We report a population-based, retrospective study of 396 Icelandic people diagnosed with glioma in the years 1940-1995. The purpose of this study was to test whether astrocytomas, other glial tumors, other central nervous system tumors, or other cancers aggregate in families identified through glioma probands who were of Icelandic origin. Pedigrees of the 396 cases were traced by the Genetical Committee of the University of Iceland and linked to the Icelandic Cancer Registry.

Heterotopic ossification of peripheral nerve ("neuritis ossificans"): report of two cases.

Objective And Importance: Heterotopic ossification ("neuritis ossificans") is among the least frequently encountered reactive lesions in peripheral nerves. Only two cases have been described previously, one in the median nerve of a 34-year-old man, and the other in the ulnar nerve of an adult woman. The architecture of this lesion is distinctly zonal.

Primary sarcomas of the brain and spinal cord: a study of 18 cases.

Primary sarcomas of the central nervous system are exceedingly rare. We reviewed the clinicopathologic features of 18 primary central nervous system sarcomas diagnosed from 1959 through 1999. Median age at diagnosis of the nine female and nine male patients was 28 years (range 3-63 years).

'Spindle cell oncocytoma' of the adenohypophysis: a tumor of folliculostellate cells?

We describe five primary tumors of the adenohypophysis featuring mitochondrion-rich spindle cells. The patient ages ranged from 53 to 71 years (mean 61.6 years); two were female.

Unusual case of extradural choroid plexus papilloma of the sacral canal. Case report.

An unusual case of a sacral, extradural choroid plexus papilloma involving the S1-3 level is described. This 50-year-old woman presented with a 4-month history of pain involving her right buttock, perineum, and leg. Contrast-enhanced magnetic resonance (MR) imaging of the spine revealed a well-defined, mildly enhancing sacral canal mass at the S1-3 level; its appearance was consistent with that of a benign tumor.

Effect of Dopamine Agonists on Lactotroph Adenomas of the Human Pituitary.

Dopamine (DA) agonists cause reduction of blood prolactin level and tumor shrinkage in most patients with lactotroph adenoma. Our aim was to investigate the cellular mechanism of tumor shrinkage by determining mitotic, MIB-1, p27, and apoptotic indices, as well as microvessel density (MVD), surface microvessel density (SMD). ploidy, and other nuclear parameters.

Pituitary Changes in Ataxia-Telangiectasia Syndrome: An Immunocytochemical, In Situ Hybridization, and DNA Cytometric Study of Three Cases.

Ataxia-telangiectasia (AT) syndrome (cerebellar ataxia, oculocutaneous telangiectasias, immunodeficiency, susceptibility to infections, and neoplasia) is associated with cyto- and nucleomegaly in several organ systems. Our aim was to determine (1) whether such cellular abnormalities in the pituitary selectively involve specific cell types, and (2) the proliferation and DNA ploidy status of such cells. Three AT autopsy pituitaries were studied by histology, immunohistochemistry (pituitary hormones, MIB-1, p53 protein), in situ hybridization (pituitary hormones), and Feulgen stain image analysis for ploidy.

Vascular Endothelial Growth Factor (VEGF) Expression in Human Pituitary Adenomas and Carcinomas.

Vascular endothelial growth factor (VEGF) is a key mediator of endothelial cell proliferation, angiogenesis, and vascular permeability. Little is known about its expression in human pituitary adenomas. We examined 148 human pituitary adenomas for VEGF protein expression by immunohistochemistry.

Vascularity in Nontumorous Human Pituitaries and Incidental Microadenomas: A Morphometric Study.

The aim of the present study was to determine the microvascular angioarchitecture in the lateral and central portions of the anterior lobe as well as of the posterior lobe. The possible association between vascularity and age, sex, and pregnancy was also examined. In addition the vascular density of incidental microadenomas was investigated and compared to that of nontumorous gland.

Prognostic significance of an apoptotic index and apoptosis/proliferation ratio for patients with high-grade astrocytomas.

We evaluated the association of spontaneous apoptosis and an apoptosis/proliferation index with survival to determine the potential of such measures to serve as predictive markers for patients with glioblastoma multiforme (GBM). We examined the extent of spontaneous apoptosis in tumors from newly diagnosed patients, 75 with GBM and 21 with anaplastic astrocytoma, who were entered on treatment protocols of the North Central Cancer Treatment Group. In the group of GBM patients, those with a higher apoptotic index tended to live longer ( P = 0.

Neuromuscular choristoma of the sciatic nerve. Case report.

The authors report the findings of a neuromuscular choristoma of the sciatic nerve in an otherwise healthy 18-year-old man who presented with sensorimotor symptoms and deformities of the right leg and foot. Only a few cases of this rare tumor, also known as "neuromuscular hamartoma" or "benign triton tumor," have been reported in the surgical literature. The authors discuss the clinical presentation, radiological findings, pathological diagnosis, and surgical rationale for this case and review the associated literature.

Infiltrative astrocytomas with granular cell features (granular cell astrocytomas): a study of histopathologic features, grading, and outcome.

Granular cell astrocytomas (GCAs) are rare, incompletely characterized infiltrative gliomas that contain a prominent component of granular cells. Such tumors can readily be mistaken for reactive conditions. We studied 22 cases to explore their morphologic spectrum, establish features useful in distinguishing GCA from nonneoplastic diseases, and to determine which parameters correlate with biologic behavior.

Choristoma of the optic nerve: case report.

Objective And Importance: Optic nerve choristoma is a rare lesion composed of adipose tissue and smooth muscle involving the optic nerve. Few cases have been reported.

Clinical Presentation: A 20-year-old woman presented with a history of slowly progressive visual loss in the left eye.

A rosette-forming glioneuronal tumor of the fourth ventricle: infratentorial form of dysembryoplastic neuroepithelial tumor?

Eleven cases of a distinctive tumor of the posterior fossa are described. The patients (age range 12-59 years) presented with headache and/or ataxia. Neuroimaging revealed a relatively discrete, focally enhancing mass(es) primarily involving the aqueduct, fourth ventricle, and cerebellar vermis.

A role for chromosome 9p21 deletions in the malignant progression of meningiomas and the prognosis of anaplastic meningiomas.

Meningiomas display significant variability in terms of recurrence and survival rates, even within tumor grade. Although several recent modifications of the grading system have improved our ability to predict biologic behavior, additional prognostic markers are needed. Inactivation of the cell cycle regulator, p16 (CDKN2A), has recently been observed in a small subset of atypical and the majority of anaplastic meningiomas.

Primary neuroblastoma of the maxillary sinus.

Although neuroblastoma is the most common of extracranial solid tumors of childhood and infancy, we report the first case of an isolated neuroblastoma of a paranasal sinus. A 15-year-old girl with a right maxillary sinus mass was asymptomatic except for persistent epiphora. Computed tomography and magnetic resonance imaging scans showed that the mass extended into the nasal cavity, encroached on the lamina papyracea, and obstructed the nasofrontal duct.

Molecular markers that identify human astrocytomas and oligodendrogliomas.

The classification of human gliomas is currently based solely on neuropathological criteria. Prognostic and therapeutic parameters are dependent upon whether the tumors are deemed to be of astrocytic or oligodendroglial in origin. We sought to identify molecular reagents that might provide a more objective parameter to assist in the classification of these tumors.