A Study to Learn About Patients With Non-Small Cell Lung Cancer (NSCLC) Who Took Lorlatinib as Their First Treatment

The main purpose of the study is to learn how the lung cancer medicines work. The study also looks into treatment sequence of these medicines. This study is performed outside of clinical studies in a database in the United States in patients with metastatic or advanced non-small cell lung cancer. Non-small cell lung cancer is a group of lung cancers named for the kinds of cells found in the cancer and how the cells look under a microscope. Metastasis is when the cancer cells spread to other parts of the body. Advanced cancer is when the patient is diagnosed with stage III or stage IV cancer. This study includes patient's information from the database who: * Are aged 18 years or older. * Are confirmed to have metastatic non-small cell lung cancer on or after 1 January 2021. * Have a positive Anaplastic Lymphoma Kinase (ALK) gene mutation or rearrangement. A gene is a part of your DNA that has instructions for making things your body needs to work and a mutation or rearrangement can cause the gene not to work properly. ALK is a protein that helps control cell growth. * Received lorlatinib as their first treatment. All participants in this study had received the study medicine lorlatinib. It is a tablet that is taken by mouth at home. They continued to take the study medicine until their cancer was no longer responding. The study will look at the experiences of people receiving the study medicine. The study is based on information collected from Flatiron Health's Advanced NSCLC Panoramic dataset which includes: \- Diagnosis, cancer stage at diagnosis, date of diagnosis, birth year, type of medicinal treatment, date of treatment start and end, age, gender, etc.