Since its identification as an oncogene in glioma, IDH mutations have been identified in a number of cancer types, including a large percentage of acute myeloid leukemia and myelodysplastic syndromes [3, 4] as well as a small percentage of prostate cancer [5], cholangiocarcinoma [6, 7], and chondrosarcoma [8]. The gene discussed is IDH2; the disease is glioma.