Inclusion Criteria:  Patients with metastatic non-small cell lung cancer treated with lorlatinib who were included in the compassionate use program in Spain between November 2016 and February 2019 for those with an ALK alteration, and between November 2016 to March 2021 for those with ROS1 alteration. Patients must have been treated with at least one cycle of lorlatinib within the compassionate use program. Alive patients must have signed, dated the ethics committee approved written informed consent form in accordance with regulatory and institutional guidelines. This must be obtained before the performance of any protocol-related procedures that are not part of normal subject care.  Exclusion Criteria:  Alive patients who refuse to sign and date an ethics committee approved written informed consent form. Patients who were accepted in the compassionate use program , but did not receive treatment.