['This study determine oxidative stress and survival prospectively in advanced stage non small cell lung cancer (NSCLC) patients following cisplatin based combination chemotherapy.', "The oxidative stress levels (LPO, NO, GSH and SOD) of 144 control subjects and 203 advanced stage (IIIA/IIIB/IV) newly diagnosed NSCLC patients were assessed at pre-treatment (day '0'), and after the 3rd and 6th cycles of chemotherapy. Groups were compared by repeated measures ANOVA while comparison of survival curves was conduced by Kaplan-Meier methods.", 'The pre-treatment mean levels of LPO and NO in patients were significantly (P<0.01) higher while GSH and SOD were significantly (P<0.01) lower as compared to control. The oxidative stress was elevated more significantly (P<0.01) after the chemotherapy and was more evident in higher stage than lower stage patients. The two year overall survival (%) of stage IV patients was significantly lower (P<0.05) as compared to stage III A and III B. The proportional mortality was also maximal in stage IV patients (37.0%) followed by stage III B (31.7%) and III A (20.0%).'] Does cisplatin combination chemotherapy induce oxidative stress in advance non small cell lung cancer patients?