Prognostic analysis of patients with brain metastases from non-small cell lung cancer treated with different doses of whole brain radiotherapy / 中华放射肿瘤学杂志

ABSTRACT

Objective:To analyze the prognosis and influencing factors of patients with brain metastases from non-small cell lung cancer (NSCLC) treated with different doses of whole brain radiotherapy (WBRT).Methods:A total of 244 NSCLC patients with brain metastases who underwent WBRT in the Fourth Hospital of Hebei Medical University from 2013 to 2015 were analyzed retrospectively. According to different doses of WBRT (EQD 2Gy), they were divided into the 30-39 Gy group ( n= 104) and ≥40 Gy group ( n= 140). The intracranial progression-free survival (iPFS) and overall survival (OS) were compared betweentwo groups. According to the number of brain metastases, GPA score, KPS score, chemotherapy and targeted therapy, the prognosis of different doses of WBRT was further analyzed. Results:The median iPFS and OS of all patients were 6.9 months and 11.8 months, respectively. Univariate survival analysis: the 1-year iPFS and 1-year OS between two groups were 22.5% and 25.4%( P=0.430) and 41.1% and 46.4%( P=0.068), respectively. Multivariate survival analysis: different doses of WBRT were not associated with the improvement of iPFS and OS; independent factors influencing iPFS included local boost, gender, number of brain metastases, chemotherapy and targeted therapy; independent factors influencing OS included gender, number of brain metastases, chemotherapy and targeted therapy. Subgroup analysis: in patients with KPS≥90, the 1-year iPFS and OS of patients with WBRT ≥ 40 Gy were seemingly better than those of their counterparts with 30-39 Gy, but the difference was statistically significant only in OS ( P=0.047), the difference was not statistically significant in iPFS ( P=0.068); in patients with chemotherapy, the 1-year iPFS and OS of patients with WBRT≥40 Gy were better than those of their counterparts with 30-39 Gy ( P=0.017, P=0.012); in patients with targeted therapy, the 1-year iPFS and OS in the WBRT≥40 Gy group were better than those in the 30-39 Gy group ( P=0.012, P=0.045). Conclusions:The 30-39 Gy may be the appropriate dose of WBRT for NSCLC patients with brain metastases. WBRT≥40 Gy does not bring more benefits. WBRT≥40 Gy may benefit NSCLC patients with brain metastases with high KPS score or active systemic therapy.