Since mesothelioma symptoms can take decades to become noticeable, the disease is often progressed in a metastatic phase by the time it’s been diagnosed. What is metastatic mesothelioma? Let’s first define mesothelioma, then have a look at the illness in its metastatic incarnation.
Mesothelioma is a form of cancer that affects the mesothelium, which is a layer of cells lining, protecting and lubricating an internal organ or region of the body. Depending on the organ or region, the mesothelium is referred to by a term that’s more specific, such as the peritoneum for the lining of the abdominal cavity, the pericardium surrounding the heart, or the pleura lining the chest wall. So the most common form of the disease, pleural mesothelioma, primarily affects the chest and lungs.
In 77% to 80% of reported cases, mesothelioma is cause by the inhalation of asbestos dust, usually from construction sites, mills, shipyards and houses built prior to the mid-1970’s. Asbestos fibers lodge themselves in the mesothelium, leading to long-term inflammation, and eventually cancer.
If the cancerous tumors are benign, their growth remains limited to the originally affected region. When the tumor metastasizes, cancer cells spread to other regions of the body. In many cancers, this often means that cancer cells attach themselves to remote organs, so breast cancer cells will find their way into the liver, for example. There are reported cases of mesothelioma affecting an organ, such as the brain, that’s unrelated to the original site of tumor growth, but these are rare.
Far more frequently, metastatic mesothelioma tends to occur through a “local spread,” where cancer cells from the original tumor site attach themselves to neighboring organs and regions. In pleural mesothelioma, for instance, the cancer cells in the lining of the chest wall will often transfer to the lung, leading to shortness of breath, painful breathing, and ultimately respiratory failure. To see what this local spread looks like, see this Mesothelioma Picture guide.