Method for predicting the survival of a patient suffering from NSCLC to a cisplatin or carboplatin based chemotherapy treatment which comprises the step of determining the methylation state of a nucleic acid encoding 14-3-3 sigma in a biological sample from the patient, wherein the presence of methylation is indicative of longer survival of said patient as a response to said chemotherapy treatment. The methylation status of the 14-3-3 sigma gene can be easily determined in a serum sample.