Robert V. Jones

Pericytic-like angiotropism of glioma and melanoma cells

We have identified in malignant melanoma an angiotumoral complex in which tumor cells occupy a pericytic location along the endothelium of microvessels without evidence of intravasation. We have suggested that this pericytic-like angiotropism could be a marker of an extravascular migration of tumor cells along the abluminal surface of vessels. The extravascular migratory metastasis proposed for melanoma has close analogies with glioma migration. To compare our hypothesis of extravascular migration by melanoma with the migration of glioma cells, we have used the B16 murine melanoma cell line and the GL26 murine glioma cell line in an in vivo murine brain tumor model and in vitro using endothelial cells that have formed capillary-like structures and have been cocultivated with tumor cells. In the brain tumors, a clear progression of glioma and melanoma cells was observed along the abluminal surface of vessels, where they occupied a pericytic location along the periendothelial laminin. In vitro, time-lapse videomicroscopy recorded the migration of tumor cells toward endothelial tubules. After 24 hours, both the melanoma cells and the glioma cells were localized along the external surfaces of the vascular tubules, occupying a pericytic-like location. These similarities between glioma and melanoma support the hypothesis of an extravascular migration of melanoma cells, particularly along the abluminal surface of vessels.

Intracranial extracerebral neuroglial heterotopia: A case report and review of the literature.

Heterotopic masses of neuroglial tissue are uncommon and most frequently involve extracranial midline structures. We report an unusual case of an intracranial, extracerebral neuroglial heterotopia involving the middle and anterior cranial fossae of a 5-year-old girl who presented with facial asymmetry. The lesion was composed of mature but disorganized gray and white matter admixed with surrounding soft tissues and exhibited histologic features reminiscent of cortical dysplasia. These rare lesions have been postulated to arise from a protrusion of tissue from the neuraxis through a pial defect, from abnormalities in the migration of embryonic neuroepithelial tissue, or from an accessory evagination of the neural tube inferior to the telencephalic vesicles. Regardless of the underlying pathogenic mechanism, these lesions must be histologically distinguished from both teratomas and primary central nervous system neoplasms.

Fourth ventricular chordoid meningioma

The chordoid variant of meningioma is a histological subtype which carries with it a more aggressive clinical course and a propensity for recurrence. Similar to other meningioma subtypes, this lesion is encountered typically in the supratentorial compartment, often along the cerebral convexities. The chordoid meningioma subtype is found primarily in the adult population, and may occasionally be associated with the systemic manifestations of Castlemans disease. We present an adult patient with a rare chordoid meningioma located within the fourth ventricle. This lesion was treated with gross total resection. Chordoid meningioma must be considered within the differential diagnosis of intraventricular tumors. This histological subtype of meningioma warrants close follow-up. The patient must also be evaluated for systemic manifestations of Castlemans disease.

Clinical and Laboratory Features Distinguishing Juvenile Polymyositis and Muscular Dystrophy

To differentiate juvenile polymyositis (PM) and muscular dystrophy, both of which may present with chronic muscle weakness and inflammation.

Dysembryoplastic Neuroepithelial Tumor with Atypical Presentation: MRI and Diffusion Tensor Characteristics

We report the neuroimaging findings of a 26-year-old female patient with a biopsy-proven dysembryoplastic neuroepithelial tumor (DNET). DNETs are an uncommon, usually benign, glial-neural cortical neoplasm of children and young adults who typically present with intractable seizures. DNETs may occur in any region of the supratentorial cortex, but have a predilection for the temporal lobes. Accurate neuroimaging diagnosis is essential since patients with DNET benefit from complete resection. However, accurate differentiation from other cortical lesions may be challenging. Typical conventional Magnetic Resonance Imaging (MRI) features can help in the differentiation from other similar cortical tumors. Diffusion tensor imaging can also provide important additional diagnostic information regarding the degree of involvement of adjacent parenchyma and white matter tracts. In this case, tractography and fractional anisotropy maps demonstrated that fiber tracts surrounding the lesion were displaced, but fiber integrity was maintained, which is more suggestive of a DNET rather than a more aggressive neoplasm. Accurate identification of DNETs is essential for the purpose of rendering a timely diagnosis and start appropriate treatment.

Relapsed acute myelogenous leukemia of brachial plexus after marrow transplant

We present a detailed description of brachial plexus infiltration by acute myelogenous leukemia (AML) in the setting of a remission bone marrow biopsy, without evidence of leukemia by flow cytometric analysis. This case illustrates the possibility of dormant leukemic cells in the peripheral nervous system (PNS) in a patient in apparent clinical remission. In patients with an unexplained brachial plexopathy and a history of AML, leukemic infiltrate of the PNS must be considered. Muscle Nerve, 2012

Intraoperative Pathologic Evaluation of Central Nervous System Hemangioblastoma

Hemangioblastoma, a benign central nervous system (CNS) tumor occurring sporadically or as part of the von Hippel-Lindau (VHL) syndrome, can challenge pathologists at intraoperative consultation. Cytologic preparations are more useful than conventional cryostat sections for demonstrating the diagnostic features of hemangioblastoma during intraoperative consultation.

Neuroimaging of Tumefactive Multiple Sclerosis with Atypical Features

Tumefactive demyelinating lesions or tumefactive multiple sclerosis (TMS) constitute a unique presentation of demyelinating disease that frequently mimics intracranial neoplasm, infection or other, nondemyelinating intracranial pathology. Consequently, these lesions, which are larger than typical multiple sclerosis plaques and are generally characterized by certain MRI features including edema and incomplete ring enhancement, pose a serious diagnostic challenge that frequently prompts biopsy in initial evaluation. Biopsy can be averted when imaging features for TMS are seen on MRI. We present a biopsy-proven case of TMS with atypical imaging features, evaluated using MRI and diffusion-tensor imaging.