RTAD-06 STEREOTACTIC RADIOSURGERY VERSUS WHOLE BRAIN RADIATION THERAPY IN ELDERLY PATIENTS WITH BRAIN METASTASES: A PROPENSITY SCORE–MATCHED ANALYSIS OF THE NATIONAL CANCER DATABASE (NCDB)
Ruchit Jain, Namita Ruhela, Khalid Ahmad Qidwai, Fatma Nihan Akkoc Mustafayev, Zouina Sarfraz, Lydia Hodgson, Manmeet Singh AhluwaliaAbstract
Introduction
Whole-brain radiation therapy (WBRT) is frequently selected for elderly patients with brain metastases (BM) due to concerns regarding frailty and comorbidity. Stereotactic radiosurgery (SRS) provides effective local control with reduced neurocognitive toxicity. Elderly patients are underrepresented in prospective trials, limiting evidence to guide optimal radiation modality. Therefore, we evaluated survival outcomes with SRS versus WBRT using the National Cancer Database (NCDB).
Methods
We performed a retrospective analysis of the NCDB from 2010-2023 which included 33,380 patients ≥65 years diagnosed with BM who received SRS or WBRT. Propensity score matching was performed using demographic and clinical variables, including age, sex, comorbidities, primary tumor type, systemic therapy utilization, and treatment facility characteristics. Overall survival (OS) was estimated using Kaplan-Meier methods and compared using Cox proportional hazards models.
Results
The final cohort included 16,690 patients treated with SRS and WBRT, each. The median age was 72 years (68-77) in the SRS cohort and 71 years (68-76) in the WBRT group, with similar distribution of male/female patients between the two groups. Lung cancer was the most common primary malignancy in both cohorts (88.4% vs 94.7%). Median OS for the entire cohort was 6.57 months (6.44-6.67), with a 1-year survival of 33.5%. In the matched analysis, SRS was associated with significantly improved survival (median OS 10.9 vs 4.2 months). WBRT was associated with worse survival (HR 1.77, p = <0.001). On multivariable analysis, female sex, systemic therapy, and surgery of the primary tumor were associated with improved survival, whereas higher Charlson-Deyo score, and colorectal malignancy predicted worse outcomes.
Conclusions
In this large cohort, SRS was associated with improved survival after adjusting for treatment selection bias. These findings suggest that SRS is underutilized in elderly patients and support treatment decisions based on individual patient and disease characteristics, rather than age alone.