In 2005, approximately 26,000 new cases of small cell lung cancer were diagnosed in the United States. When compared with non-small cell lung cancer, SCLC generally has a more rapid doubling time, a higher growth fraction, and earlier development of widespread metastases. SCLC is highly sensitive to initial chemotherapy and radiotherapy. Treatment with chemotherapy plus chest radiotherapy can be curative for some patients with limited-stage SCLC, whereas most patients with extensive-stage disease who undergo chemotherapy alone experience palliated symptoms and prolonged survival. The updated 2006 NCCN guidelines include new principles of surgical resection as well as chemotherapy and radiation dosage changes. © Journal of the National Comprehensive Cancer Network.