IDH1 mutations is prognostic marker for primary glioblastoma multiforme but MGMT hypermethylation is not prognostic for primary glioblastoma multiforme

Abstract

Purpose: To establish the frequency of IDH1 mutations and MGMT methylation in primary glioblastomas.

Experimental design: We screened primary glioblastoma multiforme (GBM) in a population-based study for IDH1 mutations and MGMT methylation and correlated them with clinical data.

Results: IDH1 mutations were detected in 5 of 40 primary glioblastomas (12,5%). Primary GBM patients carrying IDH1 mutations were significantly younger, mean age of 41±5.06years, than patients with wild-type IDH1, mean age of 57±2,29years, p=0.011. The mean survival time of all GBM patients with and without IDH1 mutations was 19months (5 cases) and 16months (35 cases), respectively (p>0,05). MGMT methylation was detected in 13 of the 40 patients (32,5%). MGMT-promoter methylation did not correlate with overall survival (OS; p>0,05).

Conclusion: In summary, our study is the first study to investigate the IDH1 mutation status and MGMT methylation in primary GBMs in Turkish population and confirmed IDH1 mutation as a genetic marker for also primary GBMs. Our data are still insufficient for definite ascertainment; and our preliminary results suggest: IDH1 status shows an association with younger age and there is a lack of association between IDH1 mutation and survival time. Furthermore MGMT promoter methylation had no prognostic value and lower frequency in primary glioblastomas.

Keywords: IDH1 mutation; MGMT methylation; MS-HRM; Primary glioblastoma.