Despite advances in neurosurgery , radiotherapy and chemotherapy, the median survival in GBM patients is only 15 months from diagnosis. Immunotherapy by checkpoint inhibitors (PD1 /PDL-1) appears as a promising treatment for many cancers. However, first clinical results are disappointing for GBM. An hypothesis is the immunosuppressive activity from infiltrating non-tumor cells. Conversion of non-tumor cells from an immunosuppressive to an immuno-activating phenotype could be attempted in a therapeutic perspective.

An important and constant infiltration of cells marked with CD45 has been observed in 77 GBM studied for the prognostic value of PDL1 and IL17 infiltration (in association with Pr Ghiringhelli ; INSERM ; Dijon) . However, CD45 is present at the surface of all leucocytes. The purpose of this project is to better characterize the nature and functionality of the CD45+ cells that infiltrate GBM (lymphocytes and their sub-types, macrophages, microglial cells). Formalin-fixed paraffin-embedded GBM samples will be studied. A panel of immune cell antibody will be used for the immuno-histological (IH) study. Furthermore, the investigator will compare these data with those obtained by the nanoString technology, a multiplexed measurement of gene expression.

Inclusion Criteria:

• Formalin-fixed paraffin-embedded GBM samples from tumor bank of the pathological laboratory of the University Hospital of Amiens-Picardie.
• Histologic diagnosis of a glioblastoma according to the WHO classification of central nervous system
• Radical surgical removal in order to have enough histological material and to homogenize the main prognostic factor that is the surgical removal.
• Patients with more than 18 years old.
• Patients informed who have signed a consent form for using the tumor for research purposes without personal benefit. If patients were died, absence of objection known for the anonymous use of the tumor for scientific purpose.
• Be insured under one social security system.
• Committee for the protection of persons approval.

Exclusion Criteria:

• Relapsed GBM
• Other brain tumors.
• Medical, psychological or social conditions not allowing the comprehension of the conduct of the study for patients able to give their opinion.
• Patient under curatorship.

Histological samples of GBM