Mesothelioma, a type of cancer often found in the lungs, is almost always caused by asbestos exposure, and is 99% preventable. But every year, approximately 3,000 people in the United States, and 2,700 in the UK are diagnosed with mesothelioma – and those numbers are increasing.
We spoke to the Mesothelioma + Asbestos Awareness Center in the USA, to learn more about the four types of mesothelioma affecting the lives of thousands each year.
Identifying risk factors and causes for cancer is one of the most important areas of modern cancer research. Knowing what leads to the development of certain cancers can help us to prevent them. So how can mesothelioma still be so common, when we already know what causes it?
The only scientifically proven cause of mesothelioma is due to exposure to asbestos. Asbestos, a naturally occurring fibrous mineral, has been added to materials used in commercial and industrial capacities — including auto parts, roofing shingles, floor tiles, ceiling materials, among many others.
Exposure to asbestos, whether inhaled or ingested, can develop numerous health concerns aside from mesothelioma. The material has therefore been banned in over 55 developed countries due to health concerns. However, though asbestos has been banned for almost 20 years in the UK, its use is not yet banned in the United States.
Types of Mesothelioma
The most common location for mesothelioma to develop is the lungs — accounting for approximately 80% of cases. Though it is the most common, diagnosis is still extremely difficult since symptoms in its early stages can be very mild compared to later stages — often misdiagnosed until stage 3 or 4. Symptoms include shortness of breath and severe chest pain.
Mesothelioma is a cancer than can lie dormant in a person’s body for 20 to 50 years, leaving most patients with a poor prognosis, facing less than a year to live by the time their first symptoms appear. However, there are cases of long-term survival — around 20 years. Such hopeful outcomes are in part due to medical advancements in recent years.
While almost all mesothelioma cases are first treated with surgery, chemotherapy, and radiation — additional surgeries are available to patients who qualify. Pleurectomy/Decortication (P/D) is a surgery that involves the removal of the outer membrane of the lungs and nearby organs. Though this procedure helps to treat many symptoms of mesothelioma, it is not considered a curative operation and unfortunately results in recurrence about 80% of the time.
Extrapleural Pneumonectomy (EPP) is another option for patients who are in good physical condition. EPP involves the removal of the affected pleura, a portion of the lung, and nearby lymph nodes making it a potentially curative treatment.
Other emerging experimental treatments for pleural mesothelioma include:
- Immunotherapy: treatments that boost the body’s immune system in an effort to fight off cancer cells.
- Gene therapy: fixes genetic source of cancerous cells.
- Photodynamic therapy: Uses a photosensitizing agent and light source to kill cancer cells.
Peritoneal mesothelioma is the second most common form of asbestos-related cancer. It develops in the lining of the abdomen and often spreads to other organs including the bowel, spleen, and liver. Symptoms include severe abdominal pain and swelling caused by fluid buildup and significant weight loss.
Prognosis for this cancer, like any type of mesothelioma, is also extremely poor even with traditional treatment (surgery, chemotherapy, and radiation). However, life expectancy has significantly improved as new treatment technology has emerged, like hyperthermic intraperitoneal chemotherapy (HIPEC). HIPEC is a heated chemotherapy wash that specifically kills cancer cells within the abdomen. Surgery combined with HIPEC has shown significantly better survival rates in mesothelioma patients — many living more than five years.
It is difficult to diagnose peritoneal mesothelioma because symptoms tend to be similar to those of other diseases – such as irritable bowel syndrome, hernias, and ovarian cancer. For this reason, diagnostic tests are usually conducted first to rule out more common diseases including imaging scans to look for tumors, blood tests to look for abnormalities, and an abdominal biopsy to examine tissue.
Pericardial mesothelioma is a very rare cancer, accounting for less than 1% of all mesothelioma cases — fewer than 50 people are diagnosed annually in the US. There has only been one known pericardial mesothelioma patient who has survived longer than five years.
This cancer develops in the lining of the heart cavity preventing oxygen flow to the body — causing the patient’s health to rapidly decline. Symptoms include chest pain due to fluid build-up, arrhythmia, and murmurs. Prognosis for this type of cancer is so poor that most cases are not diagnosed until after an autopsy has been completed.
Outside of surgery, chemotherapy, and radiation — treatment options include:
- Pericardiectomy — the removal of the lining around that heart.
- Pericardiocentesis — the removal of fluid from around the heart, providing relief from some of the symptoms and increased function of the heart.
- Percutaneous Balloon Pericardiotomy — a balloon is inserted between the layers of the pericardium allowing more fluid to be removed after pericardiectomy.
Testicular mesothelioma is the most uncommon with fewer than 100 documented cases around the world. Since this form of mesothelioma is so rare there is no standard course of treatment. Only half of the limited number of patients with testicular mesothelioma will experience recurrence
Wiping Out Mesothelioma For Good
Tuesday, September 26 marks the 13th annual Mesothelioma Awareness Day (MAD), when the mesothelioma community sheds light on this form of cancer. Mesothelioma awareness is so important because the only proven cause is due to exposure to asbestos — a risk that is preventable.
Though treatments have advanced in recent years, there is much work left to be done before finding a cure. Until then, the best defense against mesothelioma is by preventing asbestos exposure. Whether inhaled or ingested, there is no safe level of asbestos exposure, so education and prevention is key. To learn more and to help advocate against asbestos, join the Asbestos Disease Awareness tweet chat and use the hashtag #EndMeso.