Table 2: Comparison of histologic distribution, molecular alterations, and prognostic impact between IDH mutated and wild type patients.

IDH1 mutated tumors*IDH2 mutated tumorsIDH wild type tumors

Histologic subtypesAstrocytic tumors448872359
 AII6143 (2)117
 AIII3317 (4)016
 GBM35427 (1)1326
Oligodendroglial tumors58434722215
 OII243182 (10)1546
 OIII220150 (5)763
 GBMO12115 (1)0106
Mixed tumors275176693
 OAII13492 (6)537
 OAIII14184 (9)156

Molecular alterationsMGMT promoter methylation587195/256 (76.2%)172/331 (52.0%)
EGFR amplification12489/609 (1.5%)196/639 (30.7%)
Complete 10q loss114857/572 (10.0%)359/576 (62.3%)
P16 deletion123263/595 (10.6%)203/637 (31.8%)
TP53 mutation39664/178 (35.9%)49/218 (22.5%)

Prognostic impactOverall survival
 Grade II309136.567.0a
 Grade III303136.920.1b
 Grade IV43526.614.2c
Progression free survival
 Grade II30941.328.5d
 Grade III30331.910.4e
 Grade IV43510.08.1f

For histologic subtypes, the number in parentheses indicates the number of mutations. ; ; ; .