Feasibility of Exosome Analysis in Cerebrospinal Fluid During the Diagnostic Workup of Metastatic Meningitis (Exo-LCR)

Study Overview
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Brief Summary
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The investigators are interested in one of the most frequent tumor types causing leptomeningeal metastasis in order to investigate whether a profile can be established by a high-throughput clinical proteomic approach. All the data acquired will allow a tailored and promising approach to improve the knowledge of metastatic tumor meningitis.

Detailed Description
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The primary objective is to describe on an exploratory basis the association between the type of proteomic profile from cerebrospinal fluid (CSF) microvesicles (from unsupervised bioinformatics analysis) and CSF cytology analysis (positive, negative, equivocal) in breast cancer patients with suspected leptomeningeal metastases, on initial CSF samples (hereafter referred to as initial proteomic profile and initial cytology).

Official Title
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Feasibility of Exosome Analysis in Cerebrospinal Fluid During the Diagnostic Workup of Metastatic Meningitis From Breast Cancer

Conditions
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Breast Cancer

Intervention / Treatment
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* Procedure: Consultation
* Procedure: Cerebral and medullary MRI, lumbar puncture, CSF sampling
* Biological: biological test


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patient with histologically proven breast cancer; Patient with suspected metastatic leptomeningeal involvement; Age ≥ 18 ans ; WHO performance status ≤ 2 ; Affiliation to the National Social Security System ; With informed and signed consent Exclusion Criteria: History of another cancer than the one for which the patient is referred; Contraindication to lumbar puncture or cerebrospinal MRI Pregnant or breastfeeding woman

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Study process<br>Consultation, Cerebral and medullary MRI, lumbar puncture, CSF sampling, blood sample, collection of breast fluid | Procedure: Consultation<br>* History of the disease, anatomopathological and molecular biological data concerning the initial tumor; Collection of treatments received and/or in progress by the patient for her meningeal tumor (chemotherapy, targeted therapy, radiotherapy, surgery, corticosteroids, antiepileptics); Evaluation of the general condition and neurological status.<br>Procedure: Cerebral and medullary MRI, lumbar puncture, CSF sampling<br>* diagnosis of leptomeningeal involvement<br>Biological: biological test<br>* 5 ml of additional CSF after diagnostic lumbar puncture for proteomic analysis, 50-100 µl of breast aspiration fluid (NAF) for patients with an existing breast tumor, for proteomic analysis 10 ml of blood for proteomic analysis<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| CSF protein composition | The CSF proteomic profile will be obtained by an unsupervised bioinformatics analysis of the CSF collected during the initial diagnostic workup for all patients and in case of renewal of the initial lumbar puncture if the 1st one was not exploitable for the CSF cytological analysis. The bioinformatics analysis will allow to obtain the protein composition and to establish proteomic profile. | 36 months | 
| cytological analysis of the CSF | The cytological analysis of the CSF will allow to obtain 3 possible results: Positive / Negative / Equivocal at the time of the initial diagnostic workup for all patients and in case of renewal of the initial LP if the 1st one was not exploitable for the cytological analysis of the CSF, for all patients. | 36 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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leptomeningeal metastases, proteomic profile, cerebrospinal fluid, cytology analysis