Validation of a novel molecular RPA classification in glioblastoma (GBM-molRPA) treated with chemoradiation: A multi-institutional collaborative study. Issue 2 (November 2018)

• Record Type: Journal Article
• Authors: Wee, Chan Woo; Kim, Il Han; Park, Chul-Kee; Kim, Jin Wook; Dho, Yun-Sik; Ohka, Fumiharu; Aoki, Kosuke; Motomura, Kazuya; Natsume, Atsushi; Kim, Nalee; Suh, Chang-Ok; Chang, Jong Hee; Kim, Se Hoon; Cho, Won Kyung; Lim, Do Hoon; Nam, Do-Hyun; Choi, Jung Won; Kim, In Ah; Kim, Chae-Yong; Oh, Young-Taek; Cho, Oyeon; Chung, Woong-Ki; Kim, Sung-Hwan; Kim, Eunji
• Is Part Of: Radiotherapy and oncology. Volume 129:Issue 2(2018)
• Page Start: 347
• Page End: 351
• Publication Date: 2018-11
• Subjects: Glioblastoma -- MGMT -- IDH1 -- Recursive partitioning analysis -- Validation; Oncology -- Periodicals; Radiotherapy -- Periodicals; Tumors -- Periodicals; Medical Oncology -- Periodicals; Neoplasms -- radiotherapy -- Periodicals; Radiotherapy -- Periodicals; Radiothérapie -- Périodiques; Cancérologie -- Périodiques; Tumeurs -- Périodiques; Electronic journals; 616.9940642
• DOI: 10.1016/j.radonc.2018.09.001
• Languages: English
• ISSNs: 0167-8140

Abstract

Highlights: A novel molecular RPA classification for glioblastoma has been externally validated. MGMT promoter methylation and IDH1 gene mutation were successfully integrated. The GBM-molRPA identifies unusual long-term glioblastoma survivors. A GBM-molRPA was confirmed for use to stratify patients in future clinical trials. Abstract: Background and purpose: A novel molecular recursive partitioning analysis classification has recently been reported integrating the MGMT promoter methylation ( MGMT meth) and IDH1 mutation ( IDH1 mut) status for glioblastoma (GBM-molRPA) patients treated with temozolomide-based chemoradiation. The current study was initiated to validate the model in a multi-institutional study. Materials and methods: Four-hundred seventy-one newly diagnosed GBM patients (validation cohort) were allocated to classes I–III of the previously reported GBM-molRPA model. Of the patients, 15.7%, 56.1%, and 28.2% patients were GBM-molRPA class I, II, and III, respectively. MGMT meth and IDH1 mut were observed in 32.3 and 8.8% of patients, respectively. In the training plus validation cohort of 692 patients, 16.2%, 60.8%, and 23.0% patients were class I, II, and III, respectively. Results: The median follow-up for survivors and the median survival (MS) of patients was 23.3 and 18.4 months, respectively. The MS for GBM-molRPA class I, II, and III was 49.7 (95% CI, 22.8–76.6), 19.2 (95% CI, 16.2–22.1), and 13.8 months (95% CI, 11.8–15.4) ( P < .001 for all comparisons) in the validation cohort. In the training plus validation cohort, the MS was 58.5 (95% CI, 40.7–76.3), 21. (95% CI, 18.6–23.3), and 14.3 months (95% CI, 12.5–16.1) ( P < .001 for all comparisons) for class I, II, and III, respectively. Conclusion: The GBM-molRPA is a valid model. This GBM-molRPA classification can be useful in clinics and guiding patient stratification in future clinical trials.