Small cell lung cancer (SCLC) is the most aggressive type of lung cancer. SCLC is characterized by rapid growth and early metastases, which are present in 60% to 80% of patients at the time of diagnosis, and SCLC should be regarded as a systemic disease regardless of stage (1). SCLC is associated with a poor survival prognosis. According to the Veterans Administration Staging System, SCLC is generally classified as either limited (LD) or extensive disease (ED) (2). Limited disease is present when the disease is confined to one hemithorax, the mediastinum, or supraclavicular nodes, which can be targeted with a single radiation portal field (Figs. 39.1 and 39.2). Disease extension outside the thorax or the existence of malignant pleural effusion is considered to be extensive disease (Fig. 39.3). Patients with SCLC are generally not candidates for surgery. Patients with extensive disease receive chemotherapy alone. In patients with limited disease, a combined radiation therapy and chemotherapy approach is used. However, staging SCLC according to the more specific TNM categories is useful and may be required for selecting patients for multimodality programs (3). Recently, in selected patients with limited disease, a multimodality therapy with hyperfractionated radiation therapy and chemotherapy followed by adjuvant surgery was claimed to have a favorable prognostic outcome.