The stages of mesothelioma have been documented by a few different methods.  The TNM system is a more modern system which is used for malignant mesothelioma. This system is based upon the severity of the tumor, metastasis, and lymph node involvement. Here’s the four stages which they divide malignant mesothelioma into.

Stage one — Present in the right or left chest cavity, may have metastasized to the lung, the pericardium, or the diaphragm on the same side. Lymph nodes aren’t involved at this stage.

Stage two — It has reached one side of a chest cavity to a lymph node near the lung area on the same side as the cancer. The cancer has now metastasized to the diaphragm, pericardium, or the lung on the identical side as the primary tumor.

Stage three — It has began to move into the chest lining, heart, esophagus, muscle, ribs, and vital organs in the chest cavity on the same side as the cancer. Lymph modes might be involved at this stage.

Stage four — It has metastasized to the pleural area and lymph nodes on the opposite side from where the cancerous tumor is.  It may have also reached the chest cavities or lungs on both sides, or even spread into the abdominal area.