After confirming a mesothelioma diagnosis, the next step is called staging. Staging is the process used to find out how far the cancer has spread. Imaging studies, such as CT scans and MRI's, help a doctor to determine the mesothelioma stage. This is important because it affects the treatment and prognosis of mesothelioma.
The most common system used for measuring mesothelioma staging is the Butchart Staging System. This staging procedure is only used for pleural mesothelioma (cancer of the lining of the lungs) because it is by far the most common type of mesothelioma.
A. Stage 1 - Localized Malignant Mesothelioma
Stage I mesothelioma is the initial stage of mesothelioma. Here, the cancerous tumor is found in the pleura (the lung lining), and may also involvesome tumors in the lung, pericardium (the lining of the heart), or the diaphragm.
B. Stage 2 Mesothelioma
In Stage II mesothelioma, in addition to the presence of mesothelioma in the pleura, mesothelioma has spread to the chest wall, esophagus, or heart. Also, mesotheliomamay have spread to the lymph nodes in the chest.
C. Stage 3 Mesothelioma
In Stage III, mesothelioma has invaded the diaphragm into the peritoneum (the lining of the heart), and may involve lymph nodes outside of the chest.
D. Stage 4 Mesothelioma
In Stage IV, mesothelioma has metastasized, spreading through the bloodstream to other organs of the body