Value of Screening MRI Brain in Stage IV Non-small Cell Lung Cancer

Inclusion Criteria: * Histologically or cytologically confirmed stage IV metastatic NSCLC, not amenable to curative treatment. * Fit for systemic treatment (PS 0-2) according to standard of care. * No symptoms of brain disease disease assessed according to standard clinical care by the thoracic oncologist. Exclusion Criteria: * Prior/concomitant therapy for stage IV disease. * Oncogenic diver mutation (e.g. EGFR, ALK, ROS1, RET, MET, and BRAF) with approved targeted treatment. * Contraindications for MRI scan with contrast as per standard of care protocol of the institution.