Prognostic associations of the G8 geriatric screening tool in the EORTC Brain Tumor Group trials 1608 and 1709 in patients with newly diagnosed glioblastoma.

e13777 Background: The G8 screening assessment tool has been validated to assess frailty in older patients with cancer. A score of 14 or less has commonly been considered to identify patients at risk of frailty. The G8 score has been implemented for all European Organisation for Research and treatment of Cancer (EORTC) clinical trials that included patients 70 years or older since 2017. Here we assessed the prognostic implications of the G8 score in older patients with newly diagnosed glioblastoma who were enrolled in EORTC clinical trials. Methods: Data from 99 patients aged 70 or older enrolled in the 1608 STEAM trial on the multikinase inhibitor zotiraciclib (NCT 03224104) (n = 23) or the 1709 MIRAGE trial on the proteasome inhibitor marizomib (NCT 03345095) (n = 76) were analyzed. We defined a G8 low group (<14) and a G8 high group (15-17). Results: The median age was 73 years, 21 patients (48%) were women and 23 patients (52%) were men. The Karnofsky performance status was 90 or more in 48 patients (52%). Steroids were taken at baseline by 55 patients (59%). The mean G8 at baseline was 14. Forty-four patients were assigned to the G8 low group whereas 49 patients were assigned to the G8 high group. Patients with a Karnofsky performance status of 90 or 100 were more often in the G8 high group (HR 5.44, 95% CI 2.17-14.46). Patients in the G8 high group had higher means for global health status scale and functioning scores at baseline than patients in the G8 low group. Treatment delivery measured by the relative dose intensity was better in patients with a high G8 than in patients with a low G8 score (HR 1.22, (95% CI 0.91-5.96). Patients in the G8 low group tended to experience more toxicity than patients in the G8 high group. Patients in the G8 high group tended to have a longer progression-free (HR 0.66, 95% CI 0.42-1.03, p = 0.066) and overall survival (HR 0.67, 95% CI 0.42-1.07, p = 0.096). A statistically significant effect was however noted when using a pre-specified adjustment model showing longer progression-free survival and overall survival in patients in the G8 high group. Conclusions: The G8 score may be a powerful tool for prognostic assessment and for patient stratification in old and frail patients with glioblastoma. It may help to identify patients in need of early involvement of a palliative care team.