In a certified lung- cancer center, patients with NSCLC and a potentially curative stage (including patients with oligometastatic disease) are prospectively enrolled if curative treatment (either definitive radio-chemotherapy or resection) cannot be performed due to large tumor size or for functional reasons. For these patients, the multidisciplinary tumor board (MDB) recommends immuno-(chemo)therapy and re-evaluation. Response is assessed radiologically including PET-CT if indicated. After review of the MDB, patients receive either definitive curative treatment or palliative treatment.