Upfront Brain Radiotherapy Improves Intracranial Progression-Free Survival but not Overall Survival in Lung Adenocarcinoma Patients with Brain Metastases: A Retrospective Single-Institutional Analysis from China

Aims: There is no consensus on the optimal opportunity of brain radiotherapy (BRT) for the patients with lung adenocarcinoma and brain metastases (BM). In the present study, we performed a retrospective review to investigate the differential benefit of upfront BRT for lung adenocarcinoma patients with BM.Methods: A total of 354 lung adenocarcinoma patients with BM from the Affiliated Cancer Hospital of Shandong University met inclusion criteria for the study. Patients were divided into two groups: upfront BRT and deferred BRT. Intracranial progression-free survival (iPFS) and Overall survival (OS) were measured from the date of brain metastases. Subgroup analyses according to gene mutation status were also performed.Results: For the entire cohort, the median iPFS of upfront BRT and deferred BRT was 16.3 and11.3 months, respectively (p =.001). The median OS of upfront BRT and deferred BRT was 27.6 and 31.5 months, respectively (p =0.813). Subgroup Analyses indicated that upfront BRT yielded a significantly longer iPFS than deferred BRT (p = 0.003) only for patients with no sensitive gene mutation. In all subgroups, the median OS was not significant different for upfront BRT and deferred BRT.Conclusion: This single-institutional retrospective showed that in patients with lung adenocarcinoma and BM, upfront BRT was associated with significantly longer iPFS, but no OS difference between upfront BRT and deferred BRT was observed. Considering the reported neurocognitive toxicities of upfront BRT, deferred BRT might be considered as an acceptable therapeutic option for the treatment of patients with lung adenocarcinoma and BM.