Previous studies have compared specific biological profiles between initial and recurrent GBM samples, including O(6)-methylguanine-DNA methyltransferase (MGMT) promoter methylation status, expression of proliferative markers or DNA copy number [10–13]; however, the aim of our study was to focus on putative changes in angiogenic pathways, excluding other potential molecular changes. The gene discussed is MGMT; the disease is glioblastoma.