Inclusion Criteria:  Pathological confirmation of NSCLC obtained from a tumor cytology or biopsy Treatment-naïve unresectable TNM stage III NSCLC (according to the 8th TNM IASLC edition). Of note, unresectability could be due to either functional limitation or anatomical extension of the tumor. Patient willing and able to complete collection of data via self-assessment questionnaires Patient without any local or systemic anti-neoplastic treatment are eligible (palliative symptomatic radiotherapy is considered best supportive care) Patients participating in other interventional or non-interventional studies can be included.  Exclusion Criteria:  Early stage NSCLC initially treated locally (surgery or other) and classified as pathological TNM stage III (according to the 8th TNM IASLC edition) At the treating physician's discretion, patient not eligible physically or psychologically to be included in a clinical trial Inability to read and/or fill out self-assessment questionnaires Patient unable to express opposition to data collection