Small cell lung cancer represents approximately 13% of the cancers of the lung and presents as extensive stage disease in 60% to 70% of patients. Sites of metastases include bone (35%), liver (25%), bone marrow (20%), brain (10%), extrathoracic lymph nodes (5%), and subcutaneous masses (5%). Small-cell lung cancer has prominent markers of neuroendocrine differentiation.
The staging classification for SCLC is the 2-stage Veterans Administration Lung Study Group system that categorizes patients as having limited or extensive disease. Limited stage SCLC is disease confined to 1 hemithorax with or without adjacent mediastinal and/or supraclavicular lymph node involvement, but without a pleural effusion. This extent of disease can be included in a tolerable radiation field. Extensive-disease SCLC is any disease beyond the definition of limited-stage disease.
There are few proven treatment options for SCLC patients who fail first-line chemotherapy. New treatment strategies must be evaluated. The need to discover active agents with better toxicity profiles continues to be of great importance. Amrubicin may be an effective treatment for this population.