A prospective data analysis of targeted therapy combined with concurrent radiation therapy for brain metastasis from NSCLC with driver gene mutation.

Abstract

e14006 Background: Previous studies have shown that brain metastases of non-small cell lung cancer (NSCLC) with positive driver genes have poor prognosis. There is still lack of prospective studies on the efficacy and safety of targeted therapy combined with concurrent radiotherapy for brain metastases(BM). Methods: NSCLC patients, with ECOG score 0-2, having MRI confirmed brain or meningeal metastases were eligible. Patients must have driver gene mutation and received corresponding targeted therapy. The intracranial radiotherapy regimen was SRS or whole brain radiotherapy. The primary objective was iPFS (intracranial progression-free survival); Secondary objectives were: iORR (intracranial objective response rate), PFS (progression-free survival), OS (overall survival). MMSE (Mini Mental State Examination) and FACT-Br was carried out before/after weekly radiotherapy and during systematic treatment. Treatment-related toxicities were assessed according RTOG/EORTC criteria. Tumor responses were evaluated using RECIST V1.1 criteria. Survival analysis was performed using the Graphprism version 6.0 by Kaplan-Meier method and log-rank test. Results: 23 NSCLC with BM was included. Among them, 10 patients were newly diagnosed with NSCLC BM. 2 patients’ BM progressed after targeted therapy. 11 NSCLC patients were newly diagnosed with BM after targeted therapy. 91.3% of patients presented an EGFR mutation, including primarily EGFR 19-exon deletion, EGFR 21-L8585R. 11.5% presented with c-MET mutation. Median age was 58.34 yrs(44-71yrs). Patients were mostly treated with Erolotinib and Gefitinib. All patients were adenocarcinoma. At last follow-up, for patients newly diagnosed with NSCLC BM, 8 patients had achieved intracranial progression, and 7 patients had reached OS, of which 1 died before completing WBRT. The median iPFS was 9.3m(95%CI:0.571-4.055) and the median OS was 11.9m (95%CI:0.2752 -2.732). As for patients who progressed after targeted therapy, one patient’s OS was 4.4m, iPFS of the other patient was 3.9m. Among NSCLC patients who were newly diagnosed with BM after targeted therapy, 8 patients had achieved intracranial progression and 5 patients had reached OS. The median iPFS was 6.13m (95%CI:0.247-1.751) and the mOS was 13.8m (95%CI:0.3660-3.634). Common adverse effects include dry skin, fatigue, dizziness, headache, anorexia, and grade I myelosuppression and no serious adverse events (SAEs); MMSE and FACT-Br scores were no significant differences at baseline and follow-up. Conclusions: In stage IV brain metastatic NSCLC with driver gene mutation, targeted therapy combined with concurrent radiotherapy for BM is tolerable, and there is no significant impact on the quality of life and cognitive function after radiotherapy. The evaluation of efficacy requires further follow-up. Support:LC2019ZD009,81972853 and 81572279.