Long-term outcome of pemetrexed maintenance for advanced nonsquamous non-small-cell lung cancer: a real-world observational cohort study.

INTRODUCTION Pemetrexed maintenance significantly improved progression-free survival (PFS) and overall survival (OS) in advanced nonsquamous non-small-cell lung cancer (NSCLC) patients not progressing after induction chemotherapy. OBJECTIVES This study is aimed at examine the association of various clinical factor and survival in a real-world cohort analysis. MATERIALS AND METHODS One hundred ninety-four patients were included and classified as "PM" cohort ("Pemetrexed Maintenance", including patients given with pemetrexed maintenance after induction chemotherapy, n=112), and "noPM" cohort ("no Pemetrexed Maintenance" including those discontinuing pemetrexed, n=82). RESULTS The median PFS was 8.8 and 5.4 months in the PM and noPM cohorts, respectively (p=0.001). The median OS was 19.6 months in the "PM" cohort and 13.2 months in the "noPM" cohort (p<0.02). In the multivariate analysis, ECOG Performance Status (PS) 0 and maintenance therapy were independently associated with improved PFS and OS. A longer median PFS was reported in patients given ≥5 cycles of pemetrexed maintenance (p<0.01). DISCUSSION These results further confirm the survival benefit of pemetrexed maintenance in a real-word population. All eligible advanced NSCLC patients should be strongly considered for at least 5 of pemetrexed maintenance.