This study aims to characterize the clinical management and outcomes of participants diagnosed with anaplastic lymphoma kinase (ALK)-positive advanced non-small cell lung cancer (NSCLC) who are being treated with alectinib in real-world clinical practice.

Inclusion Criteria

• Confirmed diagnosis of advanced NSCLC (stage IIIB, IIIC, IVA, or IVB) on or after the date of local approval for alectinib as first-line treatment and/or second-line treatment for ALK-positive advanced NSCLC and planned to receive treatment as per routine for at least one cycle (28 days) while on study
• ALK-positive as confirmed by immunohistochemistry (IHC), fluorescent in situ hybridization (FISH), next generation sequencing (NGS), or other non-specified sequencing methods, documented prior to receiving treatment with an ALK inhibitor
• Cohort 1: Currently receiving, or planned to receive, treatment for ALK-positive advanced NSCLC with alectinib as first-line treatment
• Cohort 2: Planned to receive treatment for ALK-positive advanced NSCLC with alectinib as second-line treatment
• Able to be followed-up by participating site
• Participants with advanced NSCLC who have CNS metastases are eligible for inclusion

Exclusion Criteria

• Participants not receiving alectinib for the treatment of ALK-positive advanced NSCLC according to standard of care and in line with local product information
• Participants not receiving the Roche studied medicinal product
• Participants who have received or are currently receiving alectinib as an investigational study drug in a clinical trial for the treatment of advanced NSCLC

Eligible participants will be identified in real-world clinical settings.

For eligible studies, qualified researchers may request access to individual patient level clinical data. See Roche's commitment to transparency of clinical study information here: https://go.roche.com/data\_sharing