TERT promoter mutation as an independent prognostic marker in Glioblastoma: a prospective comparative study

Abstract Introduction: Glioblastoma is the most common intrinsic malignant brain tumor in adults and it has a dismal prognosis. This study aims to evaluate the impact of the TERTp mutation as an independent prognostic biomarker in glioblastoma patients. Materials and Methods: Newly diagnosed cases of glioblastoma who have undergone surgical treatment were enrolled from 2018 to 2020. All patients undergone maximal safe resection accompanied by adjuvant therapy. The preoperative clinical and paraclinical data were documented and then regularly during the follow up. The Genetic profiling of the tumors included IDH-1 and IDH-2 mutation, MGMT promotor methylation, EGFR gene amplification and TERTp mutation. Results: The mean age of patients under study was 42.01±11.36 years; 41 patients were male (57.70%). The overall mean OS and PFS were 14.45±5.13 months and 10.66±4.87 months. The biomarker assessment showed IDH1 and TERTp mutation in 56.34% and 30.98%. The preoperative KPS and EOR>95% were related with OS and PFS. The TERTp mutant group had a lower OS and PFS than TERTp wildtype group (P=0.00). In the TERT mutant group, those with concomitant IDH1 wildtype tumor had significantly shorter OS and PFS. In multivariate analysis, EOR>95%, preoperative KPS≥80, IDH-1 mutation and TERTp-wildtype were predictive of longer PFS. The OS was determined by IDH-1 mutation, TERTp mutation and preoperative KPS. Conclusion: this study reveals that TERTp mutant glioblastoma patients have shorter OS & PFS than the TERTp-wildtype independently. The worst prognostic biomarker constellation in this study was TERTp mutation and concomitant IDH1 wildtype tumors.