Single pemetrexed is noninferior to platinum-based pemetrexed doublet as first-line treatment on elderly Chinese patients with advanced nonsquamous nonsmall cell lung cancer

BACKGROUND To evaluate the clinical efficacy and toxicity of single pemetrexed treatment compared with platinum-based pemetrexed doublet pemetrexed-based as first-line treatment for advanced nonsquamous nonsmall cell lung cancer (NS-NSCLC) in elderly Chinese patients. METHODS The study retrospectively reviewed 175 elderly Chinese patients with NS-NSCLC from June 2010 to September 2013: 90 patients received single pemetrexed treatment, 45 received pemetrexed plus oxaliplatin, and 40 received pemetrexed plus carboplatin. Clinical efficacy was assessed using disease control rate (DCR), overall survival (OS), and progression-free survival (PFS). RESULTS DCR, OS, and PFS did not significantly differ between single pemetrexed treatment (OS: 14.9 months; DCR: 62.2%; PFS: 3.3 months), pemetrexed plus oxaliplatin (OS: 16.5 months; DCR: 71.1%; PFS: 4.5 months), and pemetrexed plus carboplatin (OS: 15.5 months; DCR: 70.0%; PFS: 4.6 months) groups. Pemetrexed treatment caused significantly lower incidences of adverse events, such as hepatotoxicity and peripheral nerve injury. Performance status (PS), TNM stage, and Thymidylate synthase (TS) expression were predictive factors of DCR. Pemetrexed chemotherapy cycles, PS, and TNM stage were independent prognostic factors. CONCLUSIONS Single pemetrexed was noninferior to platinum-based pemetrexed doublet for clinical efficacy and safety in elderly Chinese patients with advanced NS-NSCLC. Chemotherapy cycles, performance status, and TNM stage were independent prognostic factors.