The MEK-inhibitor Selumetinib was recommended in a glioma patient with NF1 mutation based on preclinical and clinical study data showing durable response in pediatric low-grade glioma (ESCAT IIIA) leading to an ongoing remission over almost 1 year.26,41,42 An IDH mutation was the most common alteration within our cohort. The gene discussed is IDH1; the disease is glioma.