Stereotactic Radiosurgery With or Without Whole-Brain Radiation Therapy for Limited Brain Metastases: A Secondary Analysis of the North Central Cancer Treatment Group N0574 (Alliance) Randomized Controlled Trial

Purpose: To determine whether whole-brain radiation therapy (WBRT) is associated with improved overall survival among non-small cell lung cancer (NSCLC) patients with favorable prognoses at diagnosis. Methods and Materials: In the N0574 trial, patients with 1 to 3 brain metastases were randomized to receive stereotactic radiosurgery (SRS) or SRS plus WBRT (SRS + WBRT), with a primary endpoint of cognitive deterioration. We calculated diagnosis-specific graded prognostic assessment (DS-GPA) scores for NSCLC patients and evaluated overall survival according to receipt of WBRT and DS-GPA score using 2 separate cut-points (>= 2.0 vs < 2.0 and >= 2.5 vs < 2.5). Results: A total of 126 NSCLC patients were included for analysis, with median follow-up of 14.2 months. Data for DS-GPA calculation were available for 86.3% of all enrolled NSCLC patients. Overall, 50.0% of patients had DS-GPA score >= 2.0, and 23.0% of patients had DS-GPA scores >= 2.5. The SRS and SRS + WBRT groups were well balanced with regard to prognostic factors. The median survival according to receipt of WBRT was 11.3 months (+WBRT) and 17.9 months (-WBRT) for patients with DS-GPA >= 2.0 (favorable prognoses, PZ. 63; hazard ratio 0.86; 95% confidence interval 0.47-1.59). Median survival was 3.7 months (+WBRT) and 6.6 months (-WBRT) for patients with DS-GPA < 2.0 patients (unfavorable prognoses, PZ. 85; hazard ratio 0.95; 95% confidence interval 0.56-1.62). Outcomes according to the receipt of WBRT and DS-GPA remained similar utilizing DS-GPA >= 2.5 as a cutoff for favorable prognoses. There was no interaction between the continuum of the DS-GPA groups and WBRT on overall survival (PZ. 53). Conclusions: We observed no significant differences in survival according to receipt of WBRT in favorable-prognosis NSCLC patients. This study further supports the approach of SRS alone in the majority of patients with limited brain metastases. (C) 2017 Elsevier Inc. All rights reserved.