title: Mutated IDH1 is a favorable prognostic factor for type 2 gliomatosis cerebri.
abstract: The prognostic significance of IDH1 mutations has been demonstrated in gliomas. It is unclear whether IDH1 mutation is also a prognostic factor in gliomatosis cerebri (GC). Primary GCs can be grouped into type 1 GCs, which have the classical diffuse growth pattern without mass formation, and type 2 GCs, which form neoplastic masses in addition to classic diffuse lesions. In this study, the prognostic relevance of IDH1/2 mutations in 74 GCs (43 type 1 and 31 type 2) was evaluated. We detected 33 (44.6%) IDH1 mutations, including R132H and R132S, by bidirectional Sanger sequencing. No mutations were detected in IDH2. The percentage of 2-year overall survival for wild-type IDH1 patients was 46 vs. 72% for patients with IDH1-mutated tumors. Mutations of IDH1 were strongly correlated with both increased overall survival (OS) and progression-free survival (PFS) in patients with type 2 GCs, and IDH1 mutations were also an independent prognostic factor predicting increased OS and PFS in type 2 GC patients in multivariate analysis. However, IDH1 mutations did not correlate with survival outcomes in patients with type 1 GCs. Finally, the subgroup of GC, which has IDH1 wild-type and additional solid component showed the worst prognosis.
authors.affiliation: Department of Pathology, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Korea.  
authors.forename: Mi Jung
authors.initials: MJ
authors.lastname: Kwon
authors.forename: Sung Tae
authors.initials: ST
authors.lastname: Kim
authors.forename: Mi Jeong
authors.initials: MJ
authors.lastname: Kwon
authors.forename: Doo-Sik
authors.initials: DS
authors.lastname: Kong
authors.forename: Dageun
authors.initials: D
authors.lastname: Lee
authors.forename: Sanghui
authors.initials: S
authors.lastname: Park
authors.forename: So Young
authors.initials: SY
authors.lastname: Kang
authors.forename: Ji-Young
authors.initials: JY
authors.lastname: Song
authors.forename: Do-Hyun
authors.initials: DH
authors.lastname: Nam
authors.forename: Yukinari
authors.initials: Y
authors.lastname: Kato
authors.forename: Yoon-La
authors.initials: YL
authors.lastname: Choi
authors.forename: Yeon-Lim
authors.initials: YL
authors.lastname: Suh
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001921:Brain / Q000473:pathology*; D001932:Brain Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007521:Isocitrate Dehydrogenase / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D018302:Neoplasms, Neuroepithelial / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D011379:Prognosis; D015996:Survival Rate
chemical_list: D007521:Isocitrate Dehydrogenase; C543588:IDH1 protein, human