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, or the spreading of the cancer, 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.
Diagnosis and Prognostic Factors
Prognosis in malignant mesothelioma is difficult to assess consistently because there is great variability in the time before diagnosis and the rate of disease progression. In large retrospective series of pleural mesothelioma patients, important prognostic factors were found to be:[1,2][Level of evidence: 3iiiA]
Prognostic Scoring Systems
Two prognostic scoring systems have been developed for...