Introduction: Glioblastoma multiform (GBM) is a malignant neoplasm of the central nervous system with poor response to treatment. Multiple studies have shown that survival is associated to preoperative variables, topography and cell lineage markers; however no prospective studies have associated all these variables with survival.

Methods: Only patients in whom newly GBM was confirmed were included. Clinical data was recorded prospectively. Tumor topography, percentage of resection, and residual tumor were evaluated based on pre and postoperative MRI and volumetric analysis. Percentage of CD133+ and MFI of GFAP was measured by flow cytometry and nestin, tubulin, cathepsin B, GFAP and cystatin expressions were determined by RTPCR, in GBM biopsies. Control group consisted in samples of hippocampus resected from a non-tumoral epilelptic patient group. All variables were correlated with survival.

Results: From 30 patients who consecutive underwent surgery during the study period (from November 2012 to June 2013) GBM was confirmed in 17. The most common tumor location was periventricular (zones I and II) in 82% (Table 1). From patients, who achieved gross total resection (percentage of resection >95% and residual volumen <2cm3) (12, patients, 70.5%), the median survival was 14 months in them who underwent adjuvant chemo- and radiotherapy. Overall, data showed an increase in CD133, cathepsin B, nestin and ß3-tubulin contents in GBM samples as compared with the non-tumoral epileptic control group, but CD133, cathepsin B and nestin were significantly also associated with poor survival (Figures 1-8).

Conclusions: A significant increase in CD133, cathepsin B and nestin are prognostic factors of disease progression and poor clinical outcome.

Patient Care: Identification the prognostic value of these glioma stem-cell markers, as well as their possible roll as a new therapeutic target could be useful to personalized therapy and improve prognosis in patients suffering GBM.

Learning Objectives: By the conclusion of this session, participants should be able to realize of: 1) The lack prospective studies of prognostic factors in GBM, 2) The importance of classifying molecular subtypes of GBM, and 3) Identify which subtype of GBM has a better or worse prognosis and is responsive or nonresponsive to any given therapies.

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