Post-progression survival after treatment with epidermal growth factor receptor-tyrosine kinase inhibitor for advanced non-small cell lung cancer patients harboring epidermal growth factor receptor mutations

e19005 Background: Non-small cell lung cancer (NSCLC) patients harboring the epidermal growth factor receptor (EGFR) mutation show a survival benefit on treatment with EGFR-tyrosine kinase inhibitor (EGFR-TKI); however, few studies report on post-progression tumor behavior after treatment with EGFR-TKI. Methods: We retrospectively reviewed clinical data of stage IV or recurrent NSCLC patients harboring the EGFR mutation, who received EGFR-TKI as first-line treatment in our institute from 2009 to 2011. Results: Thirty-six patients received EGFR-TKI as first-line therapy. Thirty of these patients with recurrent NSCLC were enrolled in this study. The median age of the patients was76 years (range, 38–97), and the male/female ratio was 4/26. The median progression-free survival (PFS) after EGFR-TKI treatment was 8.2 months. Sites of relapse in patients with progressive disease (PD) were the brain, pleural effusion, bone, and lung (n=5, 13, 6, and 8, respectively). Twenty-one patients received sequential therapy: 11 patients received continued EGFR-TKI treatment beyond PD and 10 patients received second-line therapy. Second-line therapies were platinum-based doublet therapy, monotherapy, and another cycle of EGFR-TKI (n = 6, 2, and 2 patients, respectively). Post-progression survival (PPS) of all the patients after treatment with EGFR-TKI was 9.2 months, whereas that of patients who received EGFR-TKI as second-line chemotherapy was 14 months. Subgroup analysis according to the site of relapse showed that after first-line EGFR-TKI treatment, PFS tended to be higher for patients with a relapse in the brain (11.6 months) than for patients with sites of relapse other than the brain (8.2 months). Conclusions: PPS after EGFR-TKI therapy in patients treated with second-line chemotherapy was similar to the OS of NSCLC patients without an EGFR mutation. Subgroup analysis showed that patients with a relapse in the brain might survive longer.