Staging of Small-Cell Lung Cancer

Small-cell lung cancer (SCLC) is the most common and most aggressive pulmonary neuroendocrine malignancy. SCLCs account for approximately 13% of all lung cancers and are characterized by rapid growth, early development of metastatic disease, dramatic initial response to chemotherapy and radiation therapy, and frequent association with paraneoplastic syndromes. Computed tomography (CT) and positron-emission tomography (PET)/CT are the imaging modalities routinely used in the evaluation of patients with SCLC. On imaging, SCLC usually manifests as a large centrally located lung mass or as mediastinal or mediastinal and hilar lymphadenopathy. Most patients have metastatic disease at presentation. Historically, the Veterans Administration Lung Study Group (VALG) staging system has been used to stage SCLC. More recently, it has been recommended by the International Association for the Study of Lung Cancer (IASLC) that the tumor, node, metastasis (TNM) staging system replace the VALG staging system. Despite characteristic responsiveness to initial therapy, disease invariably recurs and the overall prognosis remains poor.