How is Mesothelioma staged?
Most recently the TNM staging system has been used to stage mesothelioma. However, historically, the Butchart system was used and now there is also a new staging system which may be increasingly implemented, the Brigham system. The Butchart system describes how extensive the primary tumor is, whereas the TNM system defines cancers by tumor extension, lymph node involvement, and whether there are metastases. The Brigham staging identifies how resectable a lesion may be.
Each system has four stages. Generally the first stage is localized disease which is easily resectable and involves no lymph nodes. In stage two, the cancer has spread and may affect lymph nodes, but is often treatable with surgical excision and adjunctive therapies. Stage three is extensive disease, often crossing internal boundaries such as the diaphragm but may still respond to debulking surgery and chemotherapy or radiation.. The fourth stage in all of the systems is defined by metastatic lesions.