Analyses of Exosomes in the Cerebrospinal Fluid for Breast Cancer Patients With Suspicion of Leptomeningeal Metastasis.

Benefit of Analyzing Exosomes in the Cerebrospinal Fluid During the Medical Care of Breast Cancer Patients With Suspicion of Leptomeningeal Metastasis.

This is a multicenter, interventional, prospective study among breast cancer patients with a suspicion of metastatic meningitis. The current study aims to assess the use of proteomic profile issued from cerebrospinal fluid microvesicles for diagnosis of leptomeningeal metastases.

The aim of this study is to describe the association between the initial proteomic profile issued from cerebrospinal fluid microvesicles and the initial cytological analysis of the cerebrospinal fluid in breast cancer patients with a suspicion of metastatic meningitis.

Other objectives of the study include:

• Describing the association between the initial proteomic profile and:

  • the histological types and hormonal receptors status of the breast cancer,
  • the likelihood of leptomeningeal metastasis according to the EANO-ESMO classification (Lack of evidence / possible / probable / confirmed) ,
  • the likelihood of leptomeningeal metastasis according to the EANO-ESMO classification, combined with histological type and hormonal receptors status.

• Evaluate the prognostic value of the proteomic profiling for overall survival, according to the EANO-ESMO classification and other known prognosis factors, in patients classified "possible", "probable" or "confirmed" leading to leptomeningeal metastases specific treatment,

• Evaluate the impact of the evolution of the proteomic profile a month after the start of this treatment on the overall survival, in patients with leptomeningeal metastases specific treatment,

• Evaluate the association between the proteomic profile and the EANO-ESMO classification at least 3 months after the initial EANO-ESMO classification,

• Evaluate the evolution of the proteomic profile 3 months after the initial EANO-ESMO classification, in patients initially classified "lack of evidence", broadly and according to the evolution of cytology, the administered treatments and to the EANO-ESMO response if applicable,

• Compare the proteomic profiles issued from cerebrospinal fluid and blood

Inclusion Criteria:

• Patient with histologically proven breast cancer
• Patient with suspected metastatic leptomeningitis
• Age ≥ 18 years
• Patient covered by the French social security regime
• Signed written informed consent

Exclusion Criteria:

• History of cancer other than the one being treated
• Contraindication to carrying out the lumbar puncture or cerebrospinal MRI
• Pregnant or breastfeeding patient