Molecular targets in lung cancer: current status

Lung cancer (LC) is the most frequent oncological disease worldwide. Treatment opportunities may significantly depend on the smoking status of the patients. LC in non-smokers are characterized by elevated frequency of EGFR, ALK, ROS1, RET, MET and BRAF mutations. There are highly effective inhibitors for each of the mentioned mutated kinases. Mutations in the above genes are significantly less common in smoking-induced LCs. However, LCs arising in smokers usually demonstrate high mutation burden and therefore have increased responsivity to immune checkpoint modulators. LC is the first solid tumor for which molecular diagnosis began to be utilized not only at the start of the treatment, but also during the course of therapy. Patients with EGFR-mutated LC progressing on gefitinib, erlotinib or afatinib are to be tested for EGFR T790M mutation, with subsequent administration of osimertinib in T790M-positive cases. Liquid biopsy utilizing circulating tumor DNA is being increasingly used for LC monitoring.