Glioblastoma: molecular profile and immunophenotypic analysis as prognostic tools for tailored therapy and decision making in a recent surgical series

Objective: Despite combined approaches the prognosis of Glioblastoma remains poor. However, different variants of this tumor might show different prognostic characteristics. Aim of the study is to investigate the role of molecular prognostic factors in predicting clinical outcomes in patients treated for glioblastoma. The study focuses on therapeutic and prognostic value of IDH1 gene mutations and MGMT promoter methylation status. Methods: 115 patients diagnosed and treated for glioblastoma at our institution within a period of five years (2013–2018) were included. All patients received pre-operative MRI, gross-total surgical resection and adjuvant treatments (chemotherapy and radiotherapy). Immunohistochemical analysis of histological samples was performed for IDH1 gene R132H mutations and MGMT promoter methylation status. Follow-up was conducted through clinical examination and MRI scans for a period of 60 months. Results: Mean population age was 59.21 ± 13.9 [19–85]. Overall median survival was 14 months, range 12–16. IDH1 gene mutation was identified in 30 patients (26%) and positively correlated with survival (IDH1 mutated: 32 months 95%C.I. [12–16] vs IDH1 wild type: 12 months, 95%C.I. [11–14]; p < 0.001). MGMT promoter methylation was identified in 51 patients (44%) and was positively correlated to overall survival (met-MGMT: 16 months 95%C.I. [14–19] vs non-met-MGMT: 12 months 95%C.I. [11–16]; p < 0.05). Conclusions: Our findings highlighted that molecular characterization of tumor profile provides a prognostic tool to predict clinical efficacy of treatments and prognosis. Peculiar molecular features and immunophenotypic analysis will enhance reliability and promote personalized therapeutic decision-making in order to increase global survival and quality of life in patients diagnosed and treated for glioblastoma. Keywords: Glioblastoma, IDH, MDMT, Overall survival, Free progression surviva