Troubles neurologiques

Resistance-Sized Arteries Structure and Capillary Density Changes in Glioblastoma and Meningioma Peritumoral Brain Tissue

Abstract

Nicola Boari, Gianluca EM Boari, Carolina De Ciuceis, Enzo Porteri, Luigi F Rodella, Rita Rezzani, Claudio Cornali, Damiano Rizzoni,Enrico Agabiti Rosei and Pietro Mortini

Background: Brain vessels play a relevant role in the development of malignant primary tumors. Previous studies performed in preclinical models of brain tumors demonstrated the irregular morphology of vessels in glioblastoma, characterized by multiple abnormalities in shape, permeability and relationship with the contacting structures, such as the basement membrane; however no data about microvascular structural alterations in the brain of patients affected by brain tumors have been previously reported. Methods: We studied small vessels structural alterations, microvascular rarefaction and vascular collagen content in the peritumoral brain tissue of two groups of patients, respectively affected by glioblastoma and by meningioma, who underwent a surgical operation in order to remove the tumor. The two groups of patients were matched for clinical, laboratory variables and risk factors, with the exception of sex. Results: Media to lumen ratio was significantly higher in patients with meningioma compared to patients affected by glioblastoma. Vessels in the brain surrounding glioblastomas show a less organized structure, as demonstrated by the thinner media, by the lower content in collagen and by the lower capillary density. Conclusions: For the first time, we used an in vitro ex vivo technique to analyze structural alterations of resistance sized arteries of peritumoral brain tissue at the radiological tumor-brain interface in patients affected by glioblastoma and meningioma. This approach, together with immunohistochemical evaluation of microvessel density, has supplied new data about the brain microcirculation. These findings can be the result of the aberrant angiogenic process that characterizes glioblastomas and can finally play a role in tumor growth. Further studies are needed to confirm our data, to identify the pathways that lead to this microvascular pattern and to identify possible clinical applications