Lung cancer, the most common cancer worldwide, remains the leading cause of cancer death. Approximately two-thirds of all patients with newly diagnosed non-small-cell lung cancer (NSCLC) present with advanced stage that palliative chemotherapy is the only appropriate measure. The standard treatment for this patient population consists of third generation platinum-based doublet regimen for no more than 6 cycles followed by watch and wait until disease progression (PD) before the administration of second-line and third-line systemic anticancer therapeutic agents. Patients who go on to receive second-line therapy represent a selected subgroup with an improved overall prognosis.