PATH-43. A multi-center retrospective study on lower grade gliomas in Japan

Abstract BACKGROUND The 2021 WHO classification has standardized the categorization of grade 2/3 gliomas into oligodendroglioma (Oligo) and astrocytoma (Astro). However, the prognostic impact of histological grading and treatment outcome differences remain unclear. METHODS A multicenter retrospective study was conducted using 2,059 cases that underwent surgery between 2000 and 2019 across 20 institutions in Japan. Among these, 503 Oligo and 436 Astro cases with confirmed IDH1/2 mutation and 1p/19q codeletion status were analyzed. RESULTS Histological grade 3 was associated with significantly lower 10-year survival rates compared to grade 2 in both Oligo (G2: 90.9%, G3: 73.8%) and Astro (G2: 66.6%, G3: 60.0%). IDH2 mutations were more frequent in Oligo than Astro (5.7% vs. 1.1%) and in grade 3 than grade 2 tumors (4.9% vs. 2.2%). CDKN2A/B homozygous deletion (HD) was observed at similar rates in Oligo and Astro (7.5% vs. 9.1%) but was more frequent in grade 3 than grade 2 tumors (13.4% vs. 4.3%). CDKN2A/B-HD was associated with worse prognosis in Astro but not in Oligo. Among Oligo cases (grades 2 and 3 combined), overall survival was not significantly affected by radiotherapy or chemotherapy type (ACNU-based, TMZ-based, or no chemotherapy). DISCUSSION While molecular classification is the primary determinant, histological grading retains prognostic significance. Differences in IDH2 mutation and CDKN2A/B-HD frequencies were associated with histological grade. The potential influence of histological grade as a confounding factor in treatment outcomes warrants further investigation.

Authors

Institutions

Publication Details

Journal
Neuro-Oncology
Published
2025-11-01
DOI
https://doi.org/10.1093/neuonc/noaf201.0995
Primary Topic
Glioma Diagnosis and Treatment
Type
article
Field-Weighted Citation Impact
0.00
Controls
|||
ALL TIME
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
article

PATH-43. A multi-center retrospective study on lower grade gliomas in Japan

Takashi Sasayama, Tomoo Matsutani, Kaoru Tamura, Yuichi Hirose et al.
Neuro-Oncology
Glioma Diagnosis and Treatment
article

PATH-43. A multi-center retrospective study on lower grade gliomas in Japan

Takashi Sasayama, Tomoo Matsutani, Kaoru Tamura, Yuichi Hirose, Shinichiro Koizumi, Masashi Kinoshita, Shigeo Ohba, Naoki Kagawa, Manabu Natsumeda, Shunichi Koriyama, Mitsutoshi Nakada, Kuniaki Saito, Yoshihiro Otani, Yoshihiro Tsukamoto, Makoto Ohno, Yoshiki Arakawa, Kazuhiko Kurozumi, Yukitomo Ishi, Shigeru Yamaguchi, Noriyuki Kijima, Kazuhiro Tanaka, Joji Ishida, Hirokazu Takami, Motoo Nagane, Hideyuki Arita, Nobuhiro Hata, Noriyoshi Takebe, Junya Fukai, Masamichi Takahashi, Hiroki Toda, Shunsaku Takayanagi, Yohei Mineharu, Yoshihiro Muragaki, Akihiro Inoue
article en

Abstract

Abstract BACKGROUND The 2021 WHO classification has standardized the categorization of grade 2/3 gliomas into oligodendroglioma (Oligo) and astrocytoma (Astro). However, the prognostic impact of histological grading and treatment outcome differences remain unclear. METHODS A multicenter retrospective study was conducted using 2,059 cases that underwent surgery between 2000 and 2019 across 20 institutions in Japan. Among these, 503 Oligo and 436 Astro cases with confirmed IDH1/2 mutation and 1p/19q codeletion status were analyzed. RESULTS Histological grade 3 was associated with significantly lower 10-year survival rates compared to grade 2 in both Oligo (G2: 90.9%, G3: 73.8%) and Astro (G2: 66.6%, G3: 60.0%). IDH2 mutations were more frequent in Oligo than Astro (5.7% vs. 1.1%) and in grade 3 than grade 2 tumors (4.9% vs. 2.2%). CDKN2A/B homozygous deletion (HD) was observed at similar rates in Oligo and Astro (7.5% vs. 9.1%) but was more frequent in grade 3 than grade 2 tumors (13.4% vs. 4.3%). CDKN2A/B-HD was associated with worse prognosis in Astro but not in Oligo. Among Oligo cases (grades 2 and 3 combined), overall survival was not significantly affected by radiotherapy or chemotherapy type (ACNU-based, TMZ-based, or no chemotherapy). DISCUSSION While molecular classification is the primary determinant, histological grading retains prognostic significance. Differences in IDH2 mutation and CDKN2A/B-HD frequencies were associated with histological grade. The potential influence of histological grade as a confounding factor in treatment outcomes warrants further investigation.

Neuro-OncologyVol. 27(Supplement_5)
Kanazawa University (JP), Hokkaido University of Science (JP), Tokyo Institute of Technology (JP), Fujita Health University (JP), Chiba University (JP), Okayama University (JP), Health Sciences University of Hokkaido (JP), Oita University (JP), Wakayama Medical University (JP), Kyorin University (JP), Hokkaido University (JP), Kyoto University (JP), Hamamatsu University School of Medicine (JP), Tokyo Institute of Psychiatry (JP), National Cancer Center (US), Osaka International Cancer Institute (JP), Saitama International Medical Center (JP), Tokyo Women's Medical University (JP), Hokkaido University Hospital (JP), National Cancer Center Hospital East (JP), Neurological Surgery (US), Kitano Hospital (JP), Ehime University (JP), Kobe University (JP), Niigata University (JP), The University of Tokyo (JP), Saitama Medical University (JP), The University of Osaka (JP)
Openalex Percentile: Top 52%
Glioma Diagnosis and Treatment
DOIOpen Access PDFOpenAlex
AI Navigator

Ask Laika to Summarize, Analyze, and Connect papers live on the map.

Summarize Papers & Methodologies

Extract key findings, datasets, and comparative methods across publications.

Benchmark Rankings & Visual Analytics

Rank top research institutions, authors, funders, topics, and journals by Field-Weighted Citation Impact (FWCI) and paper volume with instant charts.

Connect Distant Disciplines

Bridge topological clusters on the map to find hidden collaborative intersections.