Does the extent of brain metastasis affect outcome of non-small cell lung cancer patients treated with chemotherapy?

e20616 Background: More than one third of advanced non-small cell lung cancer (NSCLC) patients (pts) experience brain metastases in the course of their disease. Although the outcome of NSCLC pts with brain metastasis is generally poor, identifying subgroups of pts that could benefit from appropriate therapeutic approach is clinically important, particularly in EGFR tyrosine kinase inhibitor (TKI) era. Methods: A retrospective review was conducted on 85 NSCLC pts with synchronous brain metastasis who underwent at least first-line chemotherapy, after treatment (Tx) for brain metastasis (gamma knife surgery or fractionated stereotactic radiotherapy : 42, whole brain radiation therapy : 38, surgical resection : 1, and no Tx : 4) from Jan 2002 to Dec 2013. Overall survival (OS) of all pts was analyzed according to the clinicopathological characteristics, Tx modality for brain metastasis, and chemotherapy. Results: The median OS for all pts after the initiation of first-line chemotherapy was 9 months. In univariate analysis, pts who received TKI (13 months versus 6 months, p= 0.001) and third- or further-line chemotherapy (15 months versus 6 months, p< 0.001) had significantly longer median OS. The presence of extracranial extrathoracic metastasis, number of brain metastasis, and Tx modality for brain metastasis showed no significant association with OS. In multivariate analysis, third- or further-line chemotherapy (24 pts) was the only independent prognostic factor for favorable OS ( p< 0.001). Pts who underwent third- or further-line chemotherapy were characterized by high proportion of non-squamous histology ( p= 0.016), extracranial extrathoracic metastasis ( p= 0.015), and TKI Tx ( p< 0.001). Conclusions: The present study suggests that judicious but active use of chemotherapy after appropriate Tx for brain metastasis may result in favorable outcome in NSCLC pts with synchronous brain metastasis, regardless of the number of brain metastatic lesions or local Tx modalities.