If you have been diagnosed with mesothelioma, the next step may be to determine whether the cancer has spread to other areas of your body, so you can decide the most comprehensive treatment plan.

When a doctor stages cancer, the doctor determines the size, extent and degree the cancer has spread (metastasized) outside its primary site. There are four different stages used to characterize the progression and location of pleural malignant mesothelioma. Classifying the mesothelioma by stage assists you and your doctor in determining which treatments are available and which treatments would likely be most effective.

Generally, the stages of pleural malignant mesothelioma can be described as follows, with Stage I being a localized disease, and Stage IV being an extensive disease:

Mesothelioma cancer stages

Stage I (Localized, Fig. 1): In Stage IA mesothelioma, cancer is localized in the lining of the chest wall on one side, and/or in the lining of the chest cavity between the lungs or covering the diaphragm.

In Stage IB, the cancer is localized in the lining of the chest wall on one side, as well as the lining that covers the lung. Cancer may also be present in the lining of the chest cavity between the lungs and/or the lining covering the diaphragm.

Stage II (Advanced, Fig. 2): In Stage II mesothelioma, cancer has spread to the lung tissue and/or the diaphragm.

Stage III (Advanced, Fig. 3): In Stage III mesothelioma, cancer has spread to lymph nodes or the tissue between the ribs and lining of the chest wall, fat in the area between the lungs, soft tissues of the chest wall or the sac around the heart.

Stage IV (Advanced, Fig. 4): In Stage IV mesothelioma, cancer cannot be removed by surgery. It may have spread to lymph nodes anywhere in the chest or above the collarbone. Cancer has spread to the opposite side of the chest and/or to distant organs or tissues.

Doctors may use several different tests to determine which stage the mesothelioma is in. For example, a CT scan is a method that takes detailed pictures of the chest and abdomen at different angles, while a regular chest x-ray takes pictures of organs and bones. A PET scan can be used to figure out the extent to which the disease has spread. The doctor may also perform a biopsy to remove a sample of tissue, or the tumor, for testing.

In addition to the stage of mesothelioma, other factors which may affect a patient’s prognosis and treatment options include:

Questions to ask your doctor include:

As always, make sure you bring a pen and pad of paper so you can take notes during your conversation with your doctor to review later and help you make a decision. And, don’t hesitate to consult a reputable specialist for a second opinion regarding the details and stage of your pleural malignant mesothelioma, as well as your treatment options.