gms | German Medical Science

Objective: Glioblastoma is the most common malignant brain tumor in adults. The treatment consists of surgical reduction of the tumour mass, radiation and chemotherapy. A definitive cure cannot currently be achieved. In general, mean survival times range from a few months without treatment to around 15 months with combined radio-chemotherapy. Only patients with specific molecular changes in the tumour cells can achieve significantly longer overall survival.

Methods: All patients treated in our university hospital between January 2012 and December 2018 were eligible for our study. Patients’ records were reviewed for demographic (age, gender), clinical (location, side, surgery vs. biopsy, postoperative treatment, overall survival) and molecular (IDH1 mutational status, MGMT promotor methylation, ki67 index) characteristics. Statistical analyses were conducted using SPSS version 26.0.

Results: A total of 556 patients treated for glioblastoma were included. Mean age at diagnosis was 62,71±12,25 (range 21-91) years. 326 patients were male (58,6%), 235 tumours were located in the left hemisphere and 23 tumours had developed on both sides. The majority of patients underwent open surgery (N=434, 78,1%). Molecular analysis revealed IDH1/2 mutations in 4,2% of patients (N=21) and MGMT promotor methylation in 218 patients (42,9%). Median overall survival was 242,5 days. A combination of IDH1/2 mutation and MGMT promotor methylation was seen in 14 cases. Kaplan-Meier analysis demonstrated a significantly better survival for patients with IDH1/2 mutation (p<0,001) and with MGMT promotor methylation (p=0,001). Patients with IDH1/2 mutations or MGMT promotor methylation were significantly younger than patients with wild-type IDH1/2 gene or unmethylated MGMT promotor (p<0.001; p=0.046). 65,2% of patients underwent postoperative treatment with combined chemo-radiotherapy, whereas only radiotherapy, only chemotherapy was applied in 19,3% and 8,5% of patients, respectively. 39 patients received only best supportive care.

Conclusion: We present one of the largest contemporary single centre cohorts of glioblastoma patients. The incidence of molecular tumour features (IDH1/2 and MGMT) are in line with published data.