In order to assess the development of treatments and the curability of small cell lung cancer, we analysed a total of 239 patients entered in our protocol study since 1976. Median survival time was 68 weeks for 127 patients with limited disease and 48 weeks for 112 with extensive disease. Three-year survival rate was 18% for those with limited disease, whereas it was only 5% for extensive disease. The median survival time and long-term disease-free survival rate has been improved with an introduction of aggressive chemotherapy including new drugs such as etoposide and cisplatin. Chest irradiation in addition to intensive chemotherapy played a substantial, but not significant, role for prolonging patient survival in those with limited disease. Nevertheless, the pace of therapeutic advances has been slowed and appears to reach a plateau. In this paper, the authors try to find some obstacles in the treatment of the disease, and to indicate some strategies to gain a progress.