First-line epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor alone or with whole-brain radiotherapy for brain metastases in patients with EGFR-mutated lung adenocarcinoma.

Abstract

We proposed to compare the outcomes of first‐line epidermal growth factor receptor–tyrosine kinase inhibitor (EGFR‐TKI) alone with EGFR‐TKI plus whole‐brain radiotherapy (WBRT) for the treatment of brain metastases (BM) in patients with EGFR‐mutated lung adenocarcinoma. A total of 1665 patients were screened from 2008 to 2014, and 132 were enrolled in our study. Among the 132 patients, 72 (54.5%) harbored a deletion in exon 19, 97 (73.5%) showed multiple intracranial lesions, and 67 (50.8%) had asymptomatic BM. Seventy‐nine patients (59.8%) were treated with EGFR‐TKI alone, 53 with concomitant WBRT. The intracranial objective response rate was significantly higher in the EGFR‐TKI plus WBRT treatment group (67.9%) compared with the EGFR‐TKI alone group (39.2%) (P = 0.001). After a median follow‐up of 36.2 months, 62.1% of patients were still alive. The median intracranial TTP was 24.7 months (95% CI, 19.5–29.9) in patients who received WBRT, which was significantly longer than in those who received EGFR‐TKI alone, with the median intracranial TTP of 18.2 months (95% CI, 12.5–23.9) (P = 0.004). There was no significant difference in overall survival between WBRT and EGFR‐TKI alone groups, (median, 48.0 vs 41.1 months; P = 0.740). The overall survival is significantly prolonged in patients who had an intracranial TTP exceeding 22 months compared to those who developed intracranial progression <22 months after treatment, (median, 58.0 vs 28.0 months; P = 0.001). For EGFR‐mutated lung adenocarcinoma patients with BM, treatment with concomitant WBRT achieved a higher response rate of BM and significant improvement in intracranial progression‐free survival compared with EGFR‐TKI alone.