Mesothelioma Overview
What is Mesothelioma?
The body’s organs and major cavities are lined with a layer of cells called mesothelial cells. This lining is a protective barrier that provides organs with necessary lubrication. Cancer that develops in these linings is called mesothelioma. This rare cancer is caused only by exposure to asbestos, or asbestos-like minerals (such as erionite).
In America, approximately three thousand cases of mesothelioma are diagnosed every year. This figure comprises around three percent of cancer diagnoses in the US.
There are four known types of malignant mesothelioma, each named after its point of origin in the body.
- Pleural mesothelioma develops in the lining of the lungs, called the pleura. It accounts for around 70% of all mesothelioma cases. See “Types of Mesothelioma – Pleural” for more information.
- Peritoneal mesothelioma develops in the lining of the abdominal cavity, called the peritoneal membrane. Around 25% of cases are peritoneal in origin. See “Types of Mesothelioma – Peritoneal.”
- Pericardial mesothelioma develops in the lining of the heart, called the pericardium. This type accounts for no more than 5% of cases. See “Types of Mesothelioma – Pericardial.”
- Testicular mesothelioma is extremely rare, with less than one hundred recorded cases. This type develops in the tunica vaginalis—the lining of the testicles.
What Causes Mesothelioma?
Malignant mesothelioma is caused by exposure to asbestos. In very rare cases, a benign form can develop without prior exposure. Asbestos was widely used in the twentieth century in many industries, leading to exposure for millions of Americans. For more information about asbestos and its uses, please see “Asbestos Overview.”
The exact way in which asbestos causes mesothelioma is not well understood. It is believed that inhalation of asbestos fibers leads to chronic inflammation that eventually causes mesothelial cells to mutate. Mesothelioma can develop if cells mutate in a way that allows them to become cancerous. For more information, please see “Causes of Mesothelioma.”
How is Mesothelioma Diagnosed?
Mesothelioma diagnosis is a difficult process, for two reasons. First, the disease has a very long latency period of three to five decades. This means someone who has been exposed to asbestos may appear healthy for decades before they develop noticeable symptoms of mesothelioma. For most people, by the time symptoms appear, the cancer has already advanced to Stage II or even further.
Another reason mesothelioma diagnosis is difficult is that it has nonspecific symptoms. In the early stages, pleural mesothelioma symptoms resemble those of pneumonia or flu. In addition, it is difficult to distinguish between pleural mesothelioma and other types of lung cancer. For more information about symptoms, please see “Symptoms of Mesothelioma.”
Diagnosis involves giving your doctor a full medical history, undergoing a medical exam, and undergoing an array of diagnostic tests as well. If you know you’ve been exposed to asbestos, it’s important to make sure your doctor knows about it, as this may help speed up the diagnostic process. You may undergo tests such as an x-ray, MRI, or biopsy, all of which will help determine if cancer is present, where it is located, and what stage it is at. For further information, please see “Stages of Mesothelioma” and “Diagnosing Mesothelioma.”
Partly because mesothelioma is difficult to diagnose, and partly because the disease is very resistant to treatment, most people have a very poor prognosis. With current treatments, less than 50% of patients survive more than two years after diagnosis.
What Types of Treatment are Available for Mesothelioma?
There are two categories of treatment for mesothelioma: curative and palliative. Curative treatments attempt to cure the patient by removing or killing cancer cells. Palliative treatments reduce pain and discomfort to improve quality of life.
Treatments for mesothelioma include conventional treatments (surgery, chemotherapy, and radiation therapy), and experimental treatments (such as gene therapy and immunotherapy). Others, such as massage therapy, TENS therapy, and acupuncture, are considered alternative treatments. These latter treatments are considered non-curative, as they are for relieving symptoms and improving general well-being.
Mesothelioma treatment is usually ‘multi-modal,’ meaning that a patient will receive more than one type of treatment. For example, treatment may involve surgery to remove tumors, followed by chemotherapy or radiation therapy to kill the cancer cells that remain.
Experimental treatments are available to people involved in clinical trials. Patients must usually fit certain criteria to be eligible. For example, they might have to have a particular type of mesothelioma at a specific stage of progression, and not have had any other treatment.
For more treatment information, please see “Mesothelioma Treatment Overview.”
Is there anything Else I Should Know?
There are legal issues as well as health problems associated with asbestos exposure and mesothelioma. The main issue is that many companies that produced or used asbestos in the twentieth century knew that the substance was harmful—yet they made no effort to protect workers from exposure, or even inform workers that there was any danger.
Because of this, if you develop an asbestos-related disease, you may be able to claim compensation for medical expenses, lost income, and pain and suffering. For more information, please see “Mesothelioma and your Legal Options.”
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