Study of ctDNA as Prognostic Factor on Resectable Stage IIIA NSCLC Patients Treated With Neoadjuvant Treatment

Inclusion Criteria: * 1\. Previously untreated patients with histologically- or cytologically- documented NSCLC who present stage IIIA disease (according to 8th version of the International Association for the Study of Lung Cancer Staging Manual in Thoracic Oncology) and also, potentially resectable locally advanced NSCLC patients' stage IIIB with T3N2 disease according to 8th edition can be included. * 2\. Tumor should be considered resectable before study entry by a multidisciplinary team * 3\. ECOG 0-1 * 4\. Age ≥ 18 years at time of study entry * 5\. Patients that are going to be treated with neoadjuvant treatment before surgery * 6\. Patient capable of proper therapeutic compliance and accessible for correct follow-up * 7\. Patients must have signed, dated and IRB/EC-approved written informed consent form in accordance with regulatory and institutional guidelines. This must be obtained before the performance of any protocol-related procedures that are not part of normal subject care. Exclusion Criteria: * 1\. Patients who refuse to sign and date an IRB/IEC-approved written informed consent form. * 2\. No possibility of venipuncture * 3\. Any medical, mental, or psychological condition which in the opinion of the investigator would not permit the patient to complete the study or understand the patient information.