Upfront whole brain radiotherapy for multiple brain metastases in patients with EGFR-mutant lung adenocarcinoma

Purpose: This study aimed to evaluate the efficacy of upfront whole-brain radiotherapy (WBRT) in EGFR-mutant lung adenocarcinoma patients with multiple brain metastases (BM). Methods: In this study, 195 patients with EGFR mutations who had multiple BM at preliminary diagnosis were included and retrospectively reviewed. Patients were admitted to receive the following treatments in a multi-disciplinary setting: upfront WBRT followed by EGFR-TKI, concurrent EGFR-TKI and WBRT and upfront EGFR-TKI followed by WBRT. A disease-specific graded prognostic assessment (DS-GPA) was performed for all the patients. The treatment response and overall survival (OS) were assessed as well. Results: The median OS of these patients was 27 months. Objective response rate (ORR) was significantly better in upfront WBRT group than other two groups (P=0.004). Moreover, patients who received upfront WBRT (n=67) had longer OS than the concomitant group (36 vs 25 months; P=0.006) and the upfront EGFR-TKI group (36 vs 25 months; P<0.0001). The prognosis of patients with different DS-GPA scores significantly differed (P<0.0001). In concomitant group and upfront EGFR-TKIs group, patients with higher DS-GPA scores of 2-3 had more favorable prognosis compared with those with lower DS-GPA scores of 0-1.5 (27 vs 25 months; P=0.023). Patients who received EGFR-TKIs concurrently with WBRT had longer OS than those received upfront EGFR-TKIs with high DS-GPA scores. (37 vs 17 months; P=0.023). Conclusion: The use of upfront WBRT for EGFR-mutated lung adenocarcinoma patients with multiple BM can improve ORR and OS. More importantly, patients with high DS-GPA scores are recommended to receive WBRT immediately after EGFR-TKIs therapy.