The aim of this article is to analyse the impact of several molecular alterations characteristic for glioblastoma (i.e. TP53 and IDH1 mutations, CDKN2A deletion, EGFR amplification, chromosome 7 polysomy and EGFRvIII expression) in patients treated with a neurosurgical operation and with or without the following therapy (radiotherapy or radio-chemotherapy). The gene discussed is IDH1; the disease is glioblastoma.