Open-label, Multicenter, Randomized Phase II Trial of Treatment With Cisplatin and Pemetrexed or Cisplatin and Oral Vinorelbine in Chemotherapy Naïve Patients Affected by Stage IIIB-IV Non-Squamous Non-Small Cell Lung Cancer With High Thymidylate Synthase Expression

This is an open-label, multicentre, randomized phase II trial. Eligible patients with Non Small Cell Lung Cancer (NSCLC) with high Thymidylate Synthase (TS) expression , will be randomly assigned with 1:1 ratio to the following treatment Arms: A. 4 cycles of Cisplatin + Oral Vinorelbine followed by maintenance with Metronomic Oral Vinorelbine until disease progression B. 4 cycles of Cisplatin + Pemetrexed followed by maintenance with Pemetrexed until disease progression Treatment will be repeated every 21 days .