This study aims to describe the treatment patterns in clinical practice in adult patients with mNSCLC with a BRAF V600E mutation. This study will also describe Real-World Progression-Free Survival (rwPFS) and Overall Survival (OS) for treatments prescribed in routine practice for mNSCLC with BRAF V600E mutation. Adverse events (AEs) related to treatment management will also be described.

Inclusion Criteria:

• Age ≥ 18 years at the time of first-line treatment initiation for mNSCLC,
• Patients who initiated a first systemic treatment for mNSCLC in the metastatic setting from 01 December 2017 and before their study entry date (retrospectively enrolled patients), or Patients who initiated a first systemic treatment for mNSCLC (metastatic setting) at or after their study entry date (prospectively enrolled patients),
• Confirmed diagnosis of Stage IV mNSCLCat any time before study inclusion Stage IV M1a, M1borM1c, as per the American Joint Committee on Cancer (AJCC cancer) staging manual,
• Confirmed presence of BRAF V600E mutation - via tumor biopsy, metastasectomy, or liquid biopsy - at anytime before study inclusion,
• Signed ICF or non-opposition to study participation,according to local regulations.

Patients eligible for prospective QoL data collection must, in addition to the above mentioned criteria, meet ALL of the following criteria to be eligible for the study:

• Patients who initiate a first or second systemic treatment line for mNSCLC (metastatic setting) with a BRAF V600E mutation at or after their study entry date

Exclusion Criteria:

• Concurrent or another previous malignancy within 2 years of study entry, except curatively treated basal or squamous cell skin cancer, prostate intraepithelial neoplasm, in-situcarcinoma of the cervix, Bowen's disease or Gleason ≤ 6 prostate cancer,
• Previous, ongoing, or planned participation in a clinical trial involving an interventional drug as a first-or second-line systemic treatment for mNSCLC.

The study population consists of adult patients diagnosed with mNSCLC BRAF V600E mutation who initiated a 1st systemic (retrospectively enrolled patients), and patients who initiated a first metastatic treatment upon inclusion (prospectively enrolled patients). Retrospectively enrolled patients can also be eligible for second-line prospective QoL data collection and contribute to a sub-cohort of prospective patients initiating their 2nd line of treatment (LoT) after study entry. The study aims to enroll approximately 200 patients, of whom 50 patients are planned to complete full prospective follow-up for their first-line and/or second-line systemic treatment given in the metastatic setting in mNSCLC allowing for prospective QoL data collection.