This a non- interventional, multicenter, retrospective one arm trial assessing patients with histologically confirmed diagnosis of non-small cell lung cancer (NSCLC). Patients received treatment in 18 Hellenic Cooperative Oncology Group (HeCOG)- affiliated centers in Greece between 2000 and 2020. Molecular genetic alterations, including single nucleotide variants, copy number alterations, and translocations, are detected with next generation sequencing using the ForeSENTIA® NSCLC panel developed by NIPD Genetics. The aim of the trial is to assess the prevalence and prognostic value of molecular alterations in the study population.