Validation of the updated renal graded prognostic assessment (GPA) for patients with renal cancer brain metastases treated with gamma knife radiosurgery

Abstract

Introduction: Prognosis of patients with brain metastasis (BM) from renal cell carcinoma (RCC) is relevant for treatment decisions and can be estimated with the Renal Graded Prognostic Assessment (GPA). The aim of this study is to validate the updated version of this instrument in a cohort treated with Gamma Knife radiosurgery (GKRS) without prior local intracerebral therapy. Methods: Between 2007 and 2018, 100 RCC patients with BM were treated with GKRS. They were categorized according to the updated Renal GPA. Overall survival (OS), intracranial disease progression and intracranial local failure were estimated using the Kaplan-Meier method and risk factors were identi ed with Cox proportional hazard regressions.Results: Median OS was 10.4 months. Median OS for GPA categories 0.0-1.0 (10%), 1.5-2.0 (13%), 2.5-3.0 (37%) and 3.5-4.0 (31%) was 2.9, 5.5, 8.1 and 20.4 months, respectively. Karnofsky performance status <90, serum hemoglobin ≤12.5 g/dL, age >65 years and time from primary diagnosis to brain metastasis <1 year were signi cantly related with shorter survival, while presence of extracranial disease, the volume and total number of BM had no impact on OS. A total count of >4 BM was the only predictive factor for intracranial disease progression, while none of the investigated factors predicted intracranial local failure.Conclusions: This study con rms the updated Renal GPA in an independent cohort as a valuable instrument to estimate survival in patients with BM from RCC treated with GKRS.

Stereotactic radiosurgery results for brain metastasis patients with renal cancer: A validity study of Renal Graded Prognostic Assessment and proposal of a new grading index (JLGK2101 Study)

“…Very recently, van Ruitenbeek et al reported the validity of the Renal GPA system based on a relatively small number of patients, 106 renal cancer patients whose BMs were treated with gamma knife SRS. They described significant post-SRS MST differences between two pairs of subgroups, 0.0-1.0 (3.0 months) vs 1.5-4.0 (11.0, p=0.01) and 0.0-3.0 (6.0) vs 3.5-4.0 (20.0, p=0.01) [26]. However, they did not report post-SRS MST differences between three pairs of neighboring subgroups.…”

“…Furthermore, 95% CIs of the MSTs of each subgroup were not provided. Regarding pre-SRS clinical factors, they reported age, KPS, the blood hemoglobin level and time from primary cancer to BM detection to significantly impact to the survival of patients [26] .…”