Improving the Odds - Long Term Survivors of Glioblastoma Multiforme (GBM)

Abstract

Abstract AIMS To review the data of patients in NHS Tayside who survived >24 months from a diagnosis of GBM, identifying trends in: (i) fixed demographic features; (ii) genetic mutations; (iii) treatment pathways. METHOD A retrospective case note review of patients with a new diagnosis of GBM 2015-2020, identifying those with >2 year survival. Data analysed: demographics (gender, age), mutations (IDH1, MGMT), and treatment (surgical, chemotherapy/radiotherapy). RESULTS 84 patients identified. 18 survived >24 months (2 year survival rate of 21.4%). Median survival = 31 months (range 24-110 months); 18 patients: M:F ratio = 1.6:1; Median age at diagnosis 54.5 (range 34-72 years); 13 methylated MGMT, 2 unmethylated (3 unknown); 2 mutated IDH1, 10 wildtype (6 unknown); 16 maximum surgical resection; 17 chemoradiation and adjuvant chemotherapy; 17 received radiation dose of 60Gy in 30#, 1 received 40Gy in 15#; 11 had disease progression requiring further treatment; 5 had no progression, 2 progressed but did not have further treatment. CONCLUSION In Stupp data a 2 year survival of 26.5% was reached. In our real world cohort, a 2 year survival of 21.4% is satisfactory. MGMT methylation was common, but not exclusively the case. Only 2 were IDH1 mutated, possibly reflecting the frequency of occurrence in the GBM population, but demonstrating that it is not a prerequisite for improved survival. Younger age, and maximal surgical resection followed by chemoradiation and adjuvant chemotherapy are associated with improved prognosis. Recognising our dataset is small, we recommend further studies using a larger cohort to improve understanding of better outcomes in this patient group.