Icotinib combined whole brain radiotherapy for patients with brain metastasis from lung adenocarcinoma harboring epidermal growth factor receptor mutation.

Background: The brain is a metastatic organ that is most prone to lung adenocarcinoma (LAC). However, the prognosis of patients with brain metastasis remains very poor. In this study, we evaluated the efficacy of icotinib plus whole brain radiation therapy (WBRT) for treating patients with brain metastasis from epidermal growth factor receptor (EGFR)-mutated LAC.

Methods: All patients received standard WBRT administered to the whole brain in 30 Gy in 10 daily fractions. Each patient was also instructed to take 125 mg icotinib thrice per day beginning from the first day of the WBRT. After completing the WBRT, maintenance icotinib was administered until the disease progressed or intolerable adverse effects were observed. Cranial progression-free survival (CPFS) and overall survival (OS) times were the primary endpoints.

Results: A total of 43 patients were enrolled in this study. Two patients (4.7%) presented a complete response (CR), whereas 20 patients (46.5%) presented a partial response (PR). The median CPFS and OS times were 11.0 and 15.0 months, respectively. The one-year CPFS rate was 40.0% for the patients harboring EGFR exon 19 deletion and 16.7% for the patients with EGFR exon 21 L858R (P=0.027).

Conclusions: The concurrent administration of icotinib and WBRT exhibited favorable effects on the patients with brain metastasis. EGFR exon 19 deletion was predictive of a long CPFS following icotinib plus WBRT.