Comparative Study Between Different Approaches to CPA-petroclival Meningiomas
Brain Neoplasms• Give an effective treatment for CPA-petroclival meningiomas and can detect the best approach for these tumors. . Improve the outcome of these patients and decease rate of recurrence.
Protocol for Evaluating a Planning Algorithm for Gamma Knife Radiosurgery
Vestibular SchwannomaBrain Metastases1 moreThe process of developing Gamma Knife radiosurgery treatment plans is today very dependent on the level of human expertise resulting in a great heterogeneity of the intrinsic qualities of the treatment planning and the quality of care delivered in radiosurgery. The existing reverse planning systems, although they have progressed considerably in recent years, produce results that are still lower than those achieved by an expert. Conventionally, an experienced dosimetric planner will act mainly on the coordinates of the position of the isocenters, on the size of the collimators, sector by sector, and on the irradiation time of each isocenters. In theory, the combination of these variables provides access to billions of combinatorics whose diversity far exceeds the computational capabilities of the human mind. The dosimetric planner therefore uses a very small part of the spectrum of possible patterns by always reproducing a limited number of empirical solutions. The company Intuitive Therapeutics has developed a new mathematical algorithm which can automatically test in a very short time all the combinatorial possibilities and converge very quickly to the solution that best meets the clinical, anatomical and dosimetric objectives defined by the neurosurgeon. The quick processing of the system also allows the operator to modify the constraints to refine the proposed result in real time. The demonstration of the reality of the performances of this algorithm would give the ability to even inexperienced users to develop high performance planning for the benefit of the patient in terms of optimizing the efficacy / toxicity ratio of the radiosurgery treatment results The primary objective is to evaluate comparatively the quality of the schedules produced by the algorithm developed by the company Innovative Therapeutics to those produced by an expert who carried out more than 15000 dosimetric plannings and radiosurgical interventions. The main criterion of comparison is the Paddick index. The secondary criteria for comparison are: Compliance index selectivity index Gradient index Maximum, minimum, average dose at risk structures Dose distribution in the target volume Treatment time (at equal source activity) Time of realization of the planning It was chosen to treat patients with vestibular Schwannoma OR multiple brain metastases (> 5) treated in single session by Gamma Knife OR para-optic meningioma in hypo-fractionated treatment on Gamma Knife with restraint mask with inclusion of visual paths in the target volume planning. The aim of the study is to show at least the non-inferiority of this new method compared to the expert user based on the Paddick Index. This index has continuous values between 0 and 1, 0 being the worst case and 1 being the ideal solution. In order to define the sample size needed for each pathology, a pilot phase is required. This phase can be performed retrospectively using treatments already defined by the expert user. This pilot phase will allow us to identify the difference that can be expected between the index values and the variability of this difference. Based on these values we will be able to determine the size of the sample allowing us to statistically test the non-inferiority, or even the superiority of this new device. The number of cases to be included during the pilot phase should be at least ten cases and a maximum of thirty cases. The choice of the number of cases to be integrated during this pilot phase will depend on the homogeneity of the differences obtained on the first cases. These values will allow us to calculate the size of the samples necessary for the study of non-inferiority as well as for the study of superiority. Depending on the calculated sizes samples we will make a choice to ensure that this study takes place in the expected duration.
Study of the Inflammatory Microenvironment in Atypical Meningiomas
Atypical MeningiomaAtypical meningiomas represent 15% of meningiomas. They present a high rate of recurrence, and therapeutic strategies are limited. There is a need for novel treatment strategies, such as immuotherapy. This is a retrospective study including 84 patients with primary diagnosis of atypical meningiomas. The presence of T cells (CD4, CD8, Treg and memory T cells) and mature dendritic cells will be quantified on whole tissue sections stained by immunohistochemistry (CD4, CD8, FOXP3, CD45RO and CD208). This could allow us to identify novel biomarkers for survival, and facilitate the selection of patients who may benefit from immunotherapeutic modalities.
Androcur® (Cyproterone Acetate) and Meningioma Development: a Genotype-environment Association Study...
MeningiomaThe primary objective of the study is to create a biobank of oral smears permitting to identify the genetic locus/loci associated with an increased risk to develop meningiomas after cyproterone acetate (CPA) (Androcur®) treatment, using a GWAS approach. As the secondary objectives, the study aims: to evaluate the importance of the genetic susceptibility. to record the frequence of homonodependant cancers occuring in female patients with Androcur® associated meningioma and in their first-degree relatives. to describe clinical, radiological, histological characteristics of the patients who have developed meningioma after cyproterone acetate exposure.
NF2 Natural History Consortium
SchwannomaVestibular2 moreOBJECTIVES: I. Define the growth rates and clinical course of NF2-related tumors in patients with neurofibromatosis type 2. Associate growth rate with physical function.
Sphenoorbital Meningioma Management.
Brain MeningiomaInvestigators will discuss the different surgical techniques for removal of spheno_orbital meningiomas with proptosis.investigators also will follow up the patient to know the outcome of removal of these tumours.