Development of brain metastases in stage III/IV non-small cell lung cancer patients treated with or without erlotinib.

Abstract

e19011 Background: Non-small cell lung cancer (NSCLC) has a risk of death from brain metastases (BM) that exceeds potential mortality from extracranial disease progression. Erlotinib has been proved to be effective for NSCLC patients. We hold a study to evaluate value of erlotinib in preventing BM in stage III/IV NSCLC patients. Methods: Pathologically confirmed NSCLC stage III/IV patients were included and divided into erlotinib group and control group according to whether erlotinib administration (at least one month) in 1- or 2-line therapy or not. Stage IV patients with BM were excluded. Patients with any EGFR-TKI treatment were excluded from control group. Times of erlotinib administration to BM and to death or last follow-up were recorded for erlotinib group. Times of corresponding 1- or 2-line chemotherapy to BM and to death or last follow-up were recorded for control group correspondingly. Time to BM, 1- and 2-year incidence of BM were end points. Results: 140 patients were included (68 in erlotinib group and 72 in control group) and all clinical characteristics between two groups were balanced. At a median follow-up of 20.0 months, the median time to BM for all patients was 28.0 months (95% CI, 23.795-32.205 months). 1- and 2-year incidence of BM were 17.8% (95% CI, 10.744-24.856%) and 38.8% (95% CI, 27.236-50.364%) respectively. The median time to BM were 42.0 months (95% CI, 15.567-68.433 months) and 19.0 months (95% CI, 11.305-26.695 months) (P=0.028) for erlotinib group and control group. Erilotinib group has a lower BM incidence than control group (1-year: 14.4%, 95% CI: 4.992%-23.808%, vs 21.1%, 95% CI: 10.712%-31.488%, P=0.384; 2-year: 26.2%, 95% CI: 18.712%-33.688%, vs 50.2%, 95% CI: 34.128%-66.272%, P=0.005). Multivariate analysis shows interval to BM were longer for erlotinib group (HR, 2.531; 95% CI, 1.272-5.051; P=0.008) and stage III disease (HR, 2.093; 95% CI, 1.035-4.231; P=0.040). Conclusions: Erlotinib administration improves time to BM and 2-year incidence of BM of stage III/IV NSCLC patients. Erlotinib administration and stage III disease predicts lower incidence of BM in all patients.