Lung cancer chemotherapy is classified into small-cell lung cancer (SCLC) and non-small-cell lung cancer (NSCLC). The basic theories of chemotherapy (dose intensity, high-dose chemotherapy, dose-dense chemotherapy, and alternative chemotherapy, among others) have been examined in clinical trials because SCLC progresses rapidly and is sensitive to chemotherapy. Sixty percent or more of SCLC patients have distant metastases at the time of initial diagnosis. Thus chemotherapy is the first choice for SCLC. However, new basic research and treatment of SCLC have stagnated in recent years. On the other hand, compared to SCLC, NSCLC shows low sensitivity to chemotherapy. Therefore the goals in treating advanced NSCLC were to prolong life and alleviate the symptoms, but not to pursue “the cure.” Of late, however, many molecular targeted drugs, such as gefitinib, erlotinib, and crizotinib, have been developed. The introduction of molecular target agents to the clinic and their development accompanying the discovery of oncogenic driver mutation (EGFR gene mutation, EML4-ALK fusion gene, and others) enabled clinical research focusing on pathogenesis of NSCLC. It indicates the precision medicine proposed by Harold Varmus. We might challenge pursuit of the goal of “the cure.”