Tumor tissue samples were also classified as IDH1-wildtype or IDH1-mutated (n = 19 and n = 22, respectively), ATRX-retained or ATRX-lost (n = 19 and n = 13, respectively), and low- or increased-cell-density (n = 21 and n = 17, respectively). This evidence concerns the gene IDH1 and neoplasm.