Real-world evaluation of the impact of radiotherapy and chemotherapy in elderly patients with glioblastoma based on age and performance status.

ABSTRACT

BACKGROUND: This retrospective study investigated the impact of, in addition to age, the management and outcomes of elderly patients with glioblastoma (GBM). METHODS: The National Cancer Database was queried between 2004 and 2015 for GBM patients age 60 years and older. Three age groups were created 60 to 69, 70 to 79, and 80 years and older, and 4 age/KPS groups "age ≥ 60/ KPS < 70" (group 1), "age 60 to 69/KPS ≥ 70" (group 2), "age 70 to 79/KPS ≥ 70" (group 3), and "age ≥ 80/KPS ≥ 70" (group 4). Multivariable (MVA) modeling with Cox regression determined predictors of survival (OS), and estimated average treatment effects analysis was performed. RESULTS: A total of 48 540 patients with a median age of 70 years (range, 60-90 years) at diagnosis, and a median follow-up of 6.8 months (range, 0-151 months) were included. Median survival was 5.0, 15.2, 9.6, and 6.8 months in groups 1, 2, 3, and 4, respectively (P < .001). On treatment effects analysis, all groups survived longer with combined chemotherapy (ChT) and radiation therapy (RT), except group 1, which survived longer with ChT alone (P < .001). RT alone was associated with the worst OS in all groups (P < .01). Across all groups, predictors of worse OS on MVA were older age, lower KPS, White, higher comorbidity score, worse socioeconomic status, community treatment, tumor multifocality, subtotal resection, and no adjuvant treatment (all P < .01). CONCLUSIONS: In elderly patients with newly diagnosed GBM, those with good KPS fared best with combined ChT and RT across all age groups. Performance status is a key prognostic factor that should be considered for management decisions in these patients.