When cancer spreads from its point of origin to other parts of the body, this is known as “metastasis.” Cancer cells can spread to other areas of the body via the lymph nodes and the bloodstream. With some forms of cancer, metastasis is predictable, allowing doctors to keep a close watch on other areas of the body that may be susceptible to the cancer.
Progression of Mesothelioma
Unfortunately, most cases of mesothelioma are not diagnosed until the disease has already progressed to Stage 3 or Stage 4. It’s common for the cancer to have already become a metastatic disease by the time the mesothelioma is diagnosed. Even after discovery, the metastasis of mesothelioma can take place as the cancer advances.
Cancer cells can move from the original site to anyplace in the body. Many types of cancer may spread to the brain or bones in later stages, but mesothelioma is different in this respect. This cancer tends to spread to the organs near the lung containing the first tumor. This is referred to as “local spread.”
It is thought that mesothelioma is a faster-traveling form of cancer than most others because of the location of the tumors in or near the lung. Because the lungs send oxygen through the body, the cancer cells from mesothelioma can enter the bloodstream more quickly and begin to travel throughout the body.
It is possible to track the advancement of mesothelioma by using a diagnostic imaging test such as an MRI or CT scan. A patient may begin to experience symptoms that are unrelated to mesothelioma, causing the doctor to deduce that the cancer may have spread elsewhere. When this happens, the imaging tests may be performed and blood tests administered.
While mesothelioma normally metastasizes locally, there are documented cases of brain metastases. However, malignant mesothelioma rarely spreads to the brain, bones, or adrenal glands. When brain metastases have occurred, the diagnosis has not been determined until the late stages of the cancer.
After the cancer reaches more remote parts of the body, treatments used are normally palliative. This means that their main purpose is not to cure the disease but to relieve associated symptoms and make the patient more comfortable. Treatments aimed at a cure are likely to have a better effect when the cancer is caught early. There are patients who have survived mesothelioma because of success with aggressive treatment options.
Pleural Mesothelioma Metastases
Typically, only late in its course does pleural mesothelioma spread outside the chest. Mesothelioma tends to spread to areas such as the ediastinum (the area between the lungs and chest), and the organs inside the mediastinum pericardium (the sac around the heart). It also spreads into the lymph nodes, chest wall, and the other lung. It also spreads to the diaphragm and peritoneum, and can reach the liver, adrenal gland, kidneys, and brain.
Mesothelioma Bone Metastases
Researchers believe that only rarely does mesothelioma spread into a patient’s bones. Moreover, even when this has happened, these bone metastases were rarely well documented. In one documented case, an MRI scan revealed that a pleural mesothelioma patient also suffered from multiple metastatic lesions to the thoracolumbar vertebrae. Doctors treated it with radiation therapy.
Treatment of Mesothelioma Metastases
Researchers note that metastasis requires the development of a new network of blood vessels in a process called “angiogenesis.” Without angiogenesis, it appears that tumors can’t grow. Some mesothelioma treatments include using so-called angiogenesis inhibitors that prevent the growth of new blood vessels.
Metastasis of mesothelioma can completely steer the treatment away from the initial course of action. At this point, it becomes important to address the cancer that is now in another part of the body with a different treatment program. Often, a combination of chemotherapy and radiation is recommended.
An oncologist with a strong background in aggressive asbestos-related diseases such as mesothelioma can suggest a treatment plan that will work best for both the mesothelioma and the metastases.