1. Long-Term Report of a Comprehensive Molecular and Genomic Analysis in NRG Oncology/RTOG 0424: A Phase II Study of Radiation and Temozolomide in High-Risk Grade II Glioma
- Author
-
Fleming, Jessica L, Pugh, Stephanie L, Fisher, Barbara J, Lesser, Glenn J, Macdonald, David R, Bell, Erica H, McElroy, Joseph P, Becker, Aline P, Timmers, Cynthia D, Aldape, Kenneth D, Rogers, C Leland, Doyle, Thomas J, Werner-Wasik, Maria, Bahary, Jean-Paul, Yu, Hsiang-Hsuan Michael, D'Souza, David P, Laack, Nadia N, Sneed, Penny K, Kwok, Young, Won, Minhee, Mehta, Minesh P, and Chakravarti, Arnab
- Subjects
Biomedical and Clinical Sciences ,Clinical Sciences ,Oncology and Carcinogenesis ,Rare Diseases ,Clinical Research ,Genetics ,Brain Cancer ,Brain Disorders ,Cancer ,Brain Neoplasms ,DNA Methylation ,DNA Modification Methylases ,DNA Repair Enzymes ,DNA-Binding Proteins ,Genomics ,Glioma ,Humans ,RNA-Binding Proteins ,Temozolomide ,Tumor Suppressor Proteins ,Oncology and carcinogenesis - Abstract
PurposeThis study sought to determine the prognostic significance of the WHO-defined glioma molecular subgroups along with additional alterations, including MGMT promoter methylation and mutations in ATRX, CIC, FUBP1, TERT, and TP53, in NRG/RTOG 0424 using long-term follow-up data.MethodsMutations were determined using an Ion Torrent sequencing panel. 1p/19q co-deletion and MGMT promoter methylation were determined by Affymetrix OncoScan and Illumina 450K arrays. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method and tested using the log-rank test. Hazard ratios were calculated using the Cox proportional hazard model. Multivariable analyses (MVAs) included patient pretreatment characteristics.ResultsWe obtained complete molecular data to categorize 80/129 eligible patients within the WHO subgroups. Of these, 26 (32.5%) were IDHmutant/co-deleted, 28 (35%) were IDHmutant/non-co-deleted, and 26 (32.5%) were IDHwild-type. Upon single-marker MVA, both IDHmutant subgroups were associated with significantly better OS and PFS (P values < .001), compared with the IDHwild-type subgroup. MGMT promoter methylation was obtained on 76 patients, where 58 (76%) were methylated and 18 (24%) were unmethylated. Single-marker MVAs demonstrated that MGMT promoter methylation was statistically significant for OS (P value < .001) and PFS (P value = .003). In a multimarker MVA, one WHO subgroup comparison (IDHmutant/co-deleted v IDHwild-type) was significant for OS (P value = .045), whereas MGMT methylation did not retain significance.ConclusionThis study reports the long-term prognostic effect of the WHO molecular subgroups, MGMT promoter methylation, and other mutations in NRG/RTOG 0424. These results demonstrate that the WHO molecular classification and MGMT both serve as strong prognostic indicators, but that MGMT does not appear to add statistically significant prognostic value to the WHO subgrouping, above and beyond IDH and 1p/19q status.
- Published
- 2021