Prognostic factors for overall survival in elderly patients with glioblastoma: Analysis of the pooled NOA-08 and Nordic trials with the CCTG-EORTC (CE.6) trial.

Abstract

Background: The majority of patients diagnosed with glioblastoma are >60 years. Three randomized trials addressed the roles of radiotherapy (RT) and temozolomide (TMZ) for elderly patients. NORDIC and NOA-08 compared RT versus TMZ, while CE.6 randomized between hypofractionated RT and RT + TMZ. All showed significant benefits for the TMZ arms, especially for those patients with O⁶-methylguanine DNA methyltransferase (MGMT) promoter-methylated tumors. This pooled analysis aimed at identifying additional factors that could improve individualized treatment recommendations.

Methods: Analyses were performed separately in the RT and TMZ arms of the pooled NORDIC and NOA-08 data, and in the RT and TMZ/RT arms of CE.6. The prognostic value of baseline clinical factors, comorbidities, and quality of life (QoL) scores were assessed.

Results: NORDIC + NOA-08 (NN) included 715 patients and CE.6 included 562 patients. Median age for NN was 71 and 73 years for CE.6. In NN and CE.6 respectively, 66.2% versus 70.5% underwent resection and 50.9% and 75.3% were on steroids. In NN, 401 patients received RT alone and 281 in CE.6, while 314 were randomized to TMZ alone in NN and 281 to concomitant RT + TMZ in CE.6. Known clinical prognostic factors, such as extent of resection and WHO performance status were confirmed, as was MGMT promoter methylation status for TMZ-treated patients. TMZ-treated patients with 2 or 3 comorbidities; hypertension, diabetes, and/or stroke had worse survival, both in NN (P = .022) and CE.6 (P = .022). Baseline QoL had a minor association with outcome.

Conclusion: Consideration of comorbidities allows improved personalized treatment decisions for elderly glioblastoma patients.