Inclusion criteria: Patients with advanced NSCLC (stages III B or IV according to the Tumor node metastasis [TNM] classification) who receive paclitaxel 175 mg/m2- and cisplatin-based palliative therapy every 3 weeks during 4 cycles; general status with a Karnofsky score of ≥70%, Eastern Cooperative Oncology Group (ECOG) ≤2, hepatic and hematic cytology tests within normal ranges, and creatinine purification >75 ml per min, who accepted to participate in the study, and who signed the letter of informed consent.