Relapsed small cell lung cancer: is more better?

Small cell lung cancer (SCLC) is a very aggressive and complex disease representing approximately 12% to 15% of all lung cancers (1). More than 90% of patients diagnosed with this disease are elderly, current or former heavy smokers (2). SCLC is characterized by rapid growth, early metastasis, and excellent initial response to chemotherapy and radiation (3). The dramatic response to frontline chemotherapy and radiation, unfortunately, contrasts with its subsequent disappointing responses in the relapsed setting. Patients with recurrent disease have a dismal survival of approximately 5 months when treated with chemotherapy (4). Topotecan is the only second-line drug approved by the Food and Drug Administration (FDA) in the United States. Response rate (RR) to topotecan are highly dependent on the progression-free survival (PFS) after frontline platinum-based therapy, reaching 25% in patients who relapsed >3 months (sensitive disease) after front-line therapy and <10% for those whose disease relapsed <3 months from initial platinum-based treatment (5).