title: A meta-analysis of temozolomide versus radiotherapy in elderly glioblastoma patients.
abstract: Temozolomide (TMZ) alone has been proposed as a promising alternative to radiotherapy (RT) in elderly glioblastoma (GBM) patients. We report a meta-analysis to systematically evaluate TMZ monotherapy in older GBM patients. A systematic literature search was performed using PubMed, EMBASE and the Cochrane database. Studies comparing TMZ versus RT in elderly patients (≥ 65 years) with newly diagnosed GBM were eligible for inclusion. Two randomized clinical trials (RCTs) and three comparative studies were included in the analyses, which revealed an overall survival (OS) advantage for TMZ compared with RT (HR [hazard ratio] 0.86, 95 % CI [confidence interval] 0.74-1.00). However, a sensitivity analysis of 2 RCTs only supported its non-inferiority (HR 0.91, 95 % CI 0.66-1.27). Most elderly patients tolerated TMZ despite an increased risk of grade 3-4 (G3-4) toxicities, especially hematological toxicities. The quality of life was similar between the groups. In the MGMT analysis, methylated tumors were associated with a longer OS than unmethylated tumors among elderly patients receiving TMZ monotherapy (HR 0.50, 95 % CI 0.35-0.70). Moreover, in patients with methylated tumors, TMZ was more beneficial than RT alone in improving OS (TMZ vs. RT: HR 0.66, 95 % CI 0.47-0.93) whereas the opposite was true for those with unmethylated tumors (HR 1.32, 95 % CI 1.00-1.76). Although the meta-analysis demonstrated the non-inferiority to RT in improving OS, TMZ alone was not a straightforward solution for elderly GBM patients because of an increased risk of G3-4 toxicities, especially hematological toxicities. MGMT testing might be helpful for determining individualized treatment.
authors.affiliation: Department of Neurosurgery, Xijing Institute of Clinical Neuroscience, Xijing Hospital, Fourth Military Medical University, Changle West Road, No. 127, Xi'an, 710032, Shaanxi, People's Republic of China.
authors.forename: An-An
authors.initials: AA
authors.lastname: Yin
authors.forename: Sang
authors.initials: S
authors.lastname: Cai
authors.forename: Yu
authors.initials: Y
authors.lastname: Dong
authors.forename: Lu-Hua
authors.initials: LH
authors.lastname: Zhang
authors.forename: Bo-Lin
authors.initials: BL
authors.lastname: Liu
authors.forename: Jin-Xiang
authors.initials: JX
authors.lastname: Cheng
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018906:Antineoplastic Agents, Alkylating / Q000627:therapeutic use*; D001932:Brain Neoplasms / Q000188:drug therapy* / Q000532:radiotherapy*; D003606:Dacarbazine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D016206:Databases, Bibliographic / Q000706:statistics & numerical data; D005909:Glioblastoma / Q000188:drug therapy* / Q000532:radiotherapy*; D006801:Humans; D017063:Outcome Assessment, Health Care; D016032:Randomized Controlled Trials as Topic; D000077204:Temozolomide
chemical_list: D018906:Antineoplastic Agents, Alkylating; D003606:Dacarbazine; D000077204:Temozolomide