Progression patterns at RECIST PD during EGFR-TKIs in advanced NSCLC patients harboring EGFR mutation.

8078 Background: The progression patterns at RECIST PD during EGFR-TKIs in advanced NSCLC patients harboring EGFR mutation are clinically heterogeneous. The aim of this study is to evaluate progression patterns at RECIST PD during EGFR-TKIs in advanced NSCLC patients harboring EGFR mutation. Methods: From 2008 to 2012, 160 consecutive patients with advanced NSCLC harboring EGFR mutation were treated with EGFR-TKIs (erlotinib or gefitinib) at our institution. Among these patients, 104 patients who experienced RECIST PD assessed by radiologic findings were retrospectively evaluated for initial response on EGFR-TKIs, progression sites, focus of progression (solitary lesion or multiple lesions), patients status at RECIST PD, and post progression survival (PPS) from RECIST PD. Results: In 104 patients, 96 (92%) patients had EGFR major mutation (Exon 19 deletion and L858R), and 49 (47%) received EGFR-TKIs as first-line. The overall response rate and median progression free survival on EGFR-TKIs was 69 % and 8.2...