Second-line chemotherapy has been established for non-small-cell lung cancer(NSCLC)and sensitive relapsed small cell lung cancer(SCLC).Molecular targeted drugs, such as EGFR- and ALK-inhibitors, have improved survival outcome remarkably in patients with NSCLC harboring EGFR mutations or EML4-ALK fusion proteins.In addition, targeted drugs that may overcome T790M-mediated EGFR-TKI resistance have been developed, and the development of future therapeutic strategies is anticipated.On the other hand, molecular targeted drugs against SCLC have not yet been developed.