Mesothelioma stages are the assessment levels that doctors utilize to determine the extent of the cancer within the body. Mesothelioma is staged between 1 and 4, depending on severity. Given how rare mesothelioma is, a formal staging classification exists only for pleural mesothelioma, which affects the lining of the lung and chest cavity.
The four stages of mesothelioma, as noted above, vary slightly within each system but can be generally characterized as indicated below.
Stage 1 Mesothelioma
In Stage 1 the tumor is localized, there is no lymph node involvement and the cancer has not spread to other organs or tissues. In this case, the cancer is likely restricted to one side of the pleura and surgical removal is possible
Stage 2 Mesothelioma
In Stage 2, the tumor is larger and has invaded the lung or diaphragm. Lymph nodes may also be involved. In this case, surgical resection may be possible though the cancer has likely spread to both sides of the pleura.
Stage 3 Mesothelioma
In Stage 3, mesothelioma has invaded a single region or area such as the chest wall, esophagus, lymph nodes and surgical resection is generally ruled out as an effective treatment.
Stage 4 Mesothelioma
In Stage 4, mesothelioma has invaded multiple regions such as different areas of the chest wall, the diaphragm and/or the pericardium. Lymph glands are also involved and the cancer has spread to other organs. Surgical removal provides no value in this case as the disease has likely metastasized well beyond its origin.