Severe Headaches Associated With Higher Temperatures, Lower Barometric Pressures

A study of more than 7,000 patients provides some of the first large-scale data on how environmental conditions --

Needle Biopsies Safe In 'Eloquent' Areas Of Brain, Study Suggests

ScienceDaily - 2 days ago

Scientists have concluded that performing a stereotactic needle biopsy in an area of the brain associated with language or other important functions carries no greater risk than a similar biopsy in a less critical area of the brain...

Preoperative embolization for AVM's

Stroke. 2009 May 28. [Epub ahead of print]

Adjuvant Embolization With N-Butyl Cyanoacrylate in the Treatment of Cerebral Arteriovenous Malformations. Outcomes, Complications, and Predictors of Neurologic Deficits.

Starke RM, Komotar RJ, Otten ML, Hahn DK, Fischer LE, Hwang BY, Garrett MC, Sciacca RR, Sisti MB, Solomon RA, Lavine SD, Connolly ES, Meyers PM.

From the Department of Neurosurgery, Columbia University, New York, NY; the Department of Neurosurgery, Northwestern University, Chicago, Ill; and the Department of Interventional Neuroradiology, Columbia University, New York, NY.

BACKGROUND AND PURPOSE: The purpose of this study was to assess the frequency, severity, and predictors of neurological deficits after adjuvant embolization for cerebral arteriovenous malformations. METHODS: From 1997 to 2006, 202 of 275 patients with arteriovenous malformation received embolization before microsurgery (n=176) or radiosurgery (n=26). Patients were examined before and after endovascular embolization and at clinical follow-up (mean, 43.4+/-34.6 months). Outcome was classified according to the modified Rankin Scale. New neurological deficits after embolization were defined as minimal (no change in overall modified Rankin Scale), moderate (modified Rankin Scale 2). RESULTS: Two hundred two patients were treated in 377 embolization procedures. There were a total of 29 new clinical deficits after embolization (8% of procedures; 14% of patients), of which 19 were moderate or significant. Postembolization deficits resolved in a significant number of patients over time (P<0.0001). style="color: rgb(255, 0, 0);">1.3% of procedures; 2.5% of patients). In multivariate analysis, the following variables significantly predicted new neurological deficit after embolization: complex arteriovenous malformation with treatment plan specifying more than one embolization procedure (OR, 2.7; 95% CI, 1.4 to 8.6), diameter <3>6 cm (OR, 6.2; 95% CI, 1.0 to 57.0), deep venous drainage (OR, 2.7; 95% CI, 1.1 to 6.9), or eloquent location (OR, 2.4; 95% CI, 1.0 to 5.7). These variables were weighted and used to compute an arteriovenous malformation Embolization Prognostic Risk Score for each patient. A score of 0 predicted no new deficits, a score of 1 predicted a new deficit rate of 6%, a score of 2 predicted a new deficit rate of 15%, a score of 3 predicted a new deficit rate of 21%, and a score of 4 predicted a new deficit rate of 50% (P<0.0001).>

Embolization has proved a valuable adjunct prior to microsurgery of arteriovenous malformations. In this paper, the authors describe risk factors for and likely deficits after AVM embolization. The results are similar to those presented by the Massachusetts General Hospital and the Barrow group in 2006 in terms of persistent deficit.

Neurosurgeon or Orthopedic Surgeon? Does it Matter?

SpineUniverse makes that case that for spine surgery, seeking out a spine specialist is the best strategy. There are also opinions on how to select a spine surgeon.

Presentations from AANS using CyberKnife

At this year's AANS meeting, doctors presented on their experience treating intracranial tumors and spinal arterial venous malformations (AVMs) with CyberKnife radiosurgery. Key findings include:

• Randall W. Porter, M.D., from Barrow Neurological Institute presented experience treating 262 patients with acoustic neuromas - also called vestibular schwannomas - with either a single fraction using the Gamma Knife or multiple fractions using the CyberKnife. Within the CyberKnife group, 67 percent of patients retained their hearing, as opposed to only 37.5 percent in the Gamma Knife group at 16 months follow-up, demonstrating the benefits of easily fractionating treatment with the CyberKnife.
• Robert L. Dodd, M.D., Ph.D., and associates from Stanford presented experience treating 27 patients with spinal AVMs using CyberKnife radiosurgery with a mean follow-up of 49 months. Findings showed that 100 percent of the patients with follow-up of greater than three years achieved significant reductions in the sizes of their AVMs. The presentation described the largest series of intramedullary spinal cord AVMs - or those that arise from cells within the spinal cord - that have been treated with radiosurgical ablation.
• Steven D. Chang, M.D., and associates from Stanford presented experience treating 93 hemangioblastomas in the brain and spine, 66 of them with CyberKnife radiosurgery. Hemangioblastomas are often surgically inaccessible, present as multiple lesions and therefore typically require multiple surgical treatments. The team at Stanford was able to achieve a 96 percent response rate at a mean follow-up of 61 months, demonstrating that radiosurgery is "an attractive alternative to multiple surgical procedures for patients with hemangioblastomas."

PTEN and immunoresistance

Loss of tumor suppressor PTEN function increases B7-H1 expression and immunoresistance in glioma.

Parsa AT, Waldron JS, Panner A, Crane CA, Parney IF, Barry JJ, Cachola KE, Murray JC, Tihan T, Jensen MC, Mischel PS, Stokoe D, Pieper RO.

Department of Neurological Surgery, University of California San Francisco, 505 Parnassus Avenue, M-779, San Francisco, California 94143, USA. parsaa@neurosurg.ucsf.edu

Cancer immunoresistance and immune escape may play important roles in tumor progression and pose obstacles for immunotherapy. Expression of the immunosuppressive protein B7 homolog 1 (B7-H1), also known as programmed death ligand-1 (PD-L1), is increased in many pathological conditions, including cancer. Here we show that expression of the gene encoding B7-H1 increases post transcriptionally in human glioma after loss of phosphatase and tensin homolog (PTEN) and activation of the phosphatidylinositol-3-OH kinase (PI(3)K) pathway. Tumor specimens from individuals with glioblastoma multiforme (GBM) had levels of B7-H1 protein that correlated with PTEN loss, and tumor-specific T cells lysed human glioma targets expressing wild-type PTEN more effectively than those expressing mutant PTEN. These data identify a previously unrecognized mechanism linking loss of the tumor suppressor PTEN with immunoresistance, mediated in part by B7-H1.

Decreased rate of infection in glioblastoma patients with allelic loss of chromosome 10q.

Aghi MK, Batchelor TT, Louis DN, Barker FG 2nd, Curry WT Jr.

Department of Neurological Surgery, University of California at San Francisco (UCSF), San Francisco, CA 94143-0112, USA. AghiM@neurosurg.ucsf.edu

INTRODUCTION: Chromosome 10q allelic loss commonly occurs in glioblastoma. Disruption of PTEN, one of three known 10q tumor suppressor genes, affects the immune system by increasing tumor expression of immunosuppressive protein B7-H1 and by increasing tumor release of Th2-inducing cytokines. While the former might impair antitumor cellular immunity, a consideration for immunotherapy, the latter could cause 10q-maintaining tumor patients to experience comparatively higher rates of bacterial infections, a source of morbidity and mortality in glioblastoma patients. METHODS: We retrospectively reviewed 58 glioblastoma patients whose tumors were designated "normal-10q" (n = 16) or "LOH-10q" (n = 42) using loss of heterozygosity (LOH) assays of microsatellite markers in constitutional/tumor DNA pairs. Records were reviewed for symptomatic, microbiologically or radiographically confirmed infections in the first 2 years after diagnosis. RESULTS: Infection occurred more frequently in "normal-10q" than "LOH-10q" patients (56% vs. 14% of patients experiencing infection; P = 0.001). "Normal-10q" patients more commonly developed all four infection types studied (urinary tract = 38% vs. 13%, craniotomy wound = 19% vs. 0%, pneumonia = 19% vs. 5%, sepsis = 6% vs. 3%). "Normal-10q" and "LOH-10q" patients had similar survival, ages, chemotherapy treatment rates, and frequency of patients on dexamethasone 1 month after radiation therapy (P = 0.4-0.98), making these factors unlikely to explain the observed difference in infection rates. CONCLUSION: While tumor mutations may inhibit antitumor immunity, the effects of these mutations on systemic immunity remain undetermined. We found higher infection rates after glioblastoma diagnosis in patients whose tumors maintained chromosome 10q than in patients whose tumors had allelic 10q loss. Differing effects of this genetic alteration on antitumor and systemic immunity may warrant further investigation, potentially providing insight into mechanisms of antitumor immunity and host defenses against local and systemic infections.

Avastin Approved

Avastin Gets New Approval for Brain Cancer

U.S. News & World Report - ‎May 7, 2009‎

Avastin, developed by Genentech, which in March was bought by Switzerland-based Roche, is already approved as treatment for various forms of colon, ...