This document provides information about small cell lung cancer (SCLC). It discusses that tobacco consumption is the primary cause of SCLC and accounts for 80-90% of lung cancer cases. It also notes that SCLC accounts for 13% of lung cancer worldwide. The natural history of untreated SCLC is rapid progression with a median survival of 2-4 months if extensive stage disease is present at diagnosis in approximately two thirds of patients. Diagnostic workup involves imaging like CT scans and PET scans to stage the cancer as well as biopsies to confirm the diagnosis. Prognostic factors like limited versus extensive stage disease and performance status impact survival outcomes.