The stage of a tumor refers to the extent to which lung cancer has spread in the body. Staging involves both evaluation of a tumor's size as well as the presence or absence of metastases in the lymph nodes or in other organs. Staging is important for determining how a particular tumor should be treated. Staging of a tumor is also critical in estimating the prognosis of a given patient, with higher-stage tumors having a worse prognosis than lower-stage tumors.
Doctors use several tests to accurately stage lung cancer, including blood tests, X-rays, CT scans, bone scans, and PET scans. An abnormal blood chemistry test may signal the presence of metastases in the bone or liver. Radiological procedures document the size of a tumor, as well as its spread to other organs.
Several staging systems have been proposed for small cell lung cancer (SCLC). These staging systems include the following:
American Joint Committee on Cancer (AJCC) Tumor, Node, and Metastasis (TNM).
Veterans Administration Lung Study Group (VALG).
International Association for the Study of Lung Cancer (IASLC).
No universally accepted definition of this term is available. Limited-stage disease (LD) SCLC is confined to the...