RESUMO
Glioblastoma is the most malignant central nervous system tumor, which represents 50% of all glial tumors. The understanding of glioma genesis, prognostic evaluation, and treatment planning has been significantly enhanced by the discovery of molecular genetic biomarkers. This study aimed to evaluate survival in patients with primary glioblastoma concerning O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation and other clinical factors. The study included 41 newly diagnosed glioblastoma patients treated from 2011 to 2014 in the 10th Military Research Hospital and Polyclinic, Poland. All patients underwent surgical resection followed by radiation and chemotherapy with alkylating agents. The MGMT promoter methylation was evaluated in all patients, and 43% were found to be methylated. In 26 and 15 cases, gross total resection and subtotal resection were conducted, respectively. Patients with a methylated MGMT promoter had a median survival of 504 days, while those without methylation had a median survival of 329 days. The group that was examined had a median age of 53. In a patient group younger than 53 years, those with methylation had significantly longer overall survival (639 days), compared to 433.5 days for patients without methylation. The most prolonged survival (551 days) was in patients with MGMT promoter methylation after gross total resection. The value of MGMT promoter methylation as a predictive biomarker is widely acknowledged. However, its prognostic significance remains unclear. Our findings proved that MGMT promoter methylation is also an essential positive prognostic biomarker.
RESUMO
AIMS: To compare 1p/19q codeletion, MGMT promoter methylation, and IDH mutation status in stereotactic biopsy and open craniotomy specimens. CLINICAL RATIONALE: The latest WHO classification of gliomas requires assessment of the expression of molecular markers. Samples can be obtained for molecular assays via open craniotomy or molecular stereotactic biopsy (MSB). However, there is uncertainty as to whether MSB is representative of the entire tumour, and therefore how reliable it is for treatment planning. PATIENTS AND METHODS: We examined 11 patients diagnosed with brain tumours suspicious of glioma who underwent open craniotomy after stereotactic biopsy and in whom multiple biomarkers were assessed in both sets of samples by methylation-specific multiplex ligation-dependent probe amplification. Institutional Review Board ethical approval was granted (KB 694/2018). RESULTS: The initial histopathological grade as determined by stereotactic biopsy was the same as in the samples obtained by open surgery. Further, the marker profile used here was valid in both high- and low-grade gliomas. CONCLUSION AND CLINICAL IMPLICATION: MSB is a reliable way to obtain material for precision medicine approaches.
