The blood-brain barrier is a highly selective anatomical and functional interface allowing a unique environment for neuro-glia networks. Blood-brain barrier dysfunction is common in most brain disorders and is associated with disease course and delayed complications. However, the mechanisms underlying blood-brain barrier opening are poorly understood. Here we demonstrate the role of the neurotransmitter glutamate in modulating early barrier permeability in vivo. Using intravital microscopy, we show that recurrent seizures and the associated excessive glutamate release lead to increased vascular permeability in the rat cerebral cortex, through activation of NMDA receptors. NMDA receptor antagonists reduce barrier permeability in the peri-ischemic brain, whereas neuronal activation using high-intensity magnetic stimulation increases barrier permeability and facilitates drug delivery. Finally, we conducted a double-blind clinical trial in patients with malignant glial tumors, using contrast-enhanced magnetic resonance imaging to quantitatively assess blood-brain barrier permeability. We demonstrate the safety of stimulation that efficiently increased blood-brain barrier permeability in 10 of 15 patients with malignant glial tumors. We suggest a novel mechanism for the bidirectional modulation of brain vascular permeability toward increased drug delivery and prevention of delayed complications in brain disorders.

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The authors report their 27-year experience regarding 35 cases of supratentorial brain metastasis from sarcoma treated in a single institution: these included ten osteosarcomas, seven leiomyosarcomas, five Ewing sarcomas, four malignant fibrous histiocytomas, three alveolar soft-part sarcomas (ASPS), two rhabdomyosarcomas, one liposarcoma, and three unclassified sarcomas. The first 15 cases of the series have already been described in a previous publication. Median survival after craniotomy was 9.8 months (range: 4-24). In patients with preoperative Karnofsky performance score (KPS) > 60 it was 12.8 months (range: 6.5-24 months) versus 5.4 months for those patients with a KPS < or = 60 (P = 0.01). Eight patients had more than one lesion, six of which were treated in the last ten years. Of the three patients with ASPS, the first two were alive at 15 and 20 months (before being lost to follow-up) whereas the third patient is alive at 24 month follow-up. The authors conclude that surgery is more effective in treating selected patients with sarcoma metastatic to the brain, and that patients with metastasis from ASPS have good prognosis when submitted to surgical treatment. The complete removal of all brain metastases "en bloc" and a KPS > 60 are associated with the best prognosis. Finally, it seems that surgical indications for multiple brain metastases from sarcoma have increased during the last ten years.

Astroblastoma is one of the rarest tumors of the central nervous system (CNS), and its classification, histogenesis, diagnosis and therapeutic management are still being debated. The typical histopathological appearance is the perivascular, astroblastic pseudorosette, which is however present in other CNS tumors. To clarify the clinical, radiological, histopathological, prognostic and therapeutic characteristics, which have been treated only recently and are not well established yet due to the rarity of this tumor, six cases of histologically proven astroblastoma were retrospectively analyzed in light of more pertinent literature and paying special attention to therapeutic remarks. Between 1996 and 2005, six patients with cerebral astroblastoma were surgically treated at the Department of Neurosciences-Neurosurgery of Sapienza University in Rome. In three cases the lesion was termed low-grade astroblastoma, and high grade in the other three, according to current standard parameters. Median age of the six patients was 36 years. The time to diagnosis ranged from 1 week to 18 months. The radiological and anatomopathological features of this lesion are described. Surgical removal was total in four cases and subtotal in two. All patients received radiotherapy: two also had chemotherapy with temozolomide (TMZ). The three patients with low-grade astroblastoma are still alive today after a follow-up of 2, 5 and 19 years, respectively. Of the three patients with high-grade lesions, one is still alive after a 7-year follow-up, while the other two survived for 17 months (progression time 15 months) and 35 months (progression-reoperation time 23 months), respectively. Conclusions radical surgical resection is the treatment of choice for astroblastomas. Radiotherapy may play an adjuvant role in the treatment of high-grade lesions. The role of chemotherapy is still very debatable. We propose an aggressive standardized treatment for those lesions that meet anaplastic criteria, owing to their postulated glial origin and the propensity to have aggressive courses, and we advocate the use of a safe adjuvant chemotherapeutic regimen with TMZ, used concomitantly and subsequently to radiotherapy, especially for the high-grade astroblastoma cases. Multicenter studies, taking into account molecular biological findings, are necessary to define a common therapeutic strategy for astroblastomas.

Not all Glioblastoma multiforme (GBM, grade IV WHO) manifest the same clinical course. Different prognostic classes may arise from different morphologic and genetic profiles. The observation of oligodendroglial foci within GBM samples and their correlation with genetic alterations may predict a better prognosis. 450 patients affected by histologically proven supratentorial cerebral GBM were treated at our institutions from January 2000 to December 2006: all patients received at least subtotal surgical removal, followed by the same standard radio-chemotherapy adjuvant treatment. In a subgroup of 36 patients (8.0%) an oligodendroglial component was observed. Molecular assessment of these cases was performed and LOH for 1p, 19q and 10q, EGFR amplification and TP53 gene expression was determined. Median age of this subgroup was 52.1 years (range: 29-78 years) vs 62.4 years in the entire GBM population. Chromosome analysis resulted as follows: LOH 1p and/or 19q in 27 cases (75.0%), LOH of 10q in 21 cases (58.1%), EGFR amplification in 14 cases (39%) and TP53 mutation in eight patients (22.2%). OS was of 20.9 months while it was 13.6 months in the entire GBM population. Progression free survival (PFS) was 10.3 months and 7.6 months the entire group. Two-year survival was of 55%. The presence of an oligodendroglial component in GBM appears to be an important prognostic factor to which better prognosis can be related. LOH 1p and 19q was significantly associated with GBM with oligodendroglial component.