In this guide, you’ll learn about Mesothelioma Cancer as a rare and serious type affecting various organs’ mesothelium or lining. You risk developing this cancer if you have been exposed to asbestos. There is a 20-40 year latency between exposure and cancer development. Every year, there are approximately 3,000 new mesothelioma cases in the United States.
Mesothelioma is a rare but aggressive type of cancer that occurs in the mesothelium, a type of membrane that lines certain body organs. The primary risk factor for developing mesothelioma cancer is asbestos exposure. Without treatment, the average life expectancy is only a few months. Treatment can extend this in certain patients.
But Mesothelioma is still incurable. And also, long-term remission is quite rare. More than 80 percent of Pleural Mesothelioma patients and up to half of peritoneal mesothelioma patients have a known history of asbestos exposure. Asbestos is a mineral that has been used for many years across a wide variety of industries due to its stability and resistance to heat.
It tends to break easily into fibers. Effectively, they can be so tiny that they can’t be seen, felt, or even smelled when suspended in the air. Asbestos fibers are naturally long, thin, and sharp. When inhaled, they can become embedded into the lung tissue and work their way into the surrounding pleura. They may also be coughed up and swallowed.
How Mesothelioma Cancer Is Influenced By Asbestos Exposure
Mesothelioma Cancer is a type of cancerous disease that begins to grow in the lining of certain organs. Most commonly, it affects the lining of the lungs (called the pleura). But it can also affect the lining of the abdomen or the lining of the heart. This information focuses on mesothelioma of the chest, sometimes called malignant pleural mesothelioma.
Inside your chest are two thin layers of cells – called the pleura or pleural membranes. Each layer is about as thin as the skin of a balloon. The inner layer covers your lungs, and the outer layer lines the inside of your rib cage. The space between the two layers is called the pleural space, and it normally contains a small amount of fluid. This fluid lubricates the two surfaces.
And as a result, it lets your lungs and chest wall move and expand as you breathe in and out. Usually, Mesothelioma Cancer Cells are known to affect only one side of your chest. As the cancer cells grow and multiply, they form many small clumps called tumors. These tumors are scattered throughout the lining of your lung and rib cage, causing it to become thicker.
Note the following key facts:
- approximately 3,000 new mesothelioma cases per year in the U.S.
- 20 million people in the U.S. are at risk of developing mesothelioma at some point in their lives
- 80% of all cases are pleural mesothelioma, which occurs in the lining of the lungs
- 20-40 years+ is the latency period between asbestos exposure and the potential development of mesothelioma
The main cause of Mesothelioma is breathing in asbestos dust. Asbestos is a naturally occurring fiber widely used in construction and other industries until the late 1990s. It was used to insulate and fireproof buildings and was commonly used in ceiling tiles, pipe insulation, boilers, and spray coatings used on ceilings and walls.
Asbestos Fibers are extremely small. When you breathe them in, they get lodged inside your lungs. These fibers cause persistent irritation to the lungs, which in some people can lead to mesothelioma. It’s unknown why some people with asbestos in their lungs develop mesothelioma, and others don’t.
The General Mesothelioma Cancer Types And Symptoms To Know
It’s important to realize that different types of Mesothelioma are found in different places in the body.
- Pleural Mesothelioma: occurs in the pleura, the lining of the lungs. This is the most common type, accounting for about 80 percent of all mesothelioma cases.
- Peritoneal Mesothelioma: occurs in the peritoneum, the lining of the digestive system. This is the next most common type, accounting for 15% of mesothelioma cases.
- Pericardial Mesothelioma: occurs in the pericardium, the lining of the heart. This type is very rare.
- Testicular Mesothelioma: occurs in the tunica vaginalis, the lining of the testes. This type is also very rare.
The symptoms of mesothelioma are different for each type. These symptoms are often similar to other diseases, much more common than mesothelioma. This can lead to a delay in diagnosis. The stage of cancer refers to how advanced it is. There are various ways to describe cancer’s stage, which differ depending on the type of mesothelioma as per the following guidelines.
Pleural Mesothelioma:
- Shortness of breath
- Chest pain
- Cough
- Difficulty swallowing
- Hoarseness of the voice
- Unexplained weight loss
- Night sweats and/or fever
Similar Symptoms can be caused by other respiratory diseases, including pneumonia, COPD (emphysema), asthma, and lung cancer. For pleural mesothelioma, there’s a formally defined staging system called the TNM staging system, which characterizes cancer by the size of the tumor, spread to lymph nodes, and metastasis (spread to distant parts of the body).
These are the stages:
- One is localized to the pleura
- Two have grown into adjacent organs and/or have spread to local lymph nodes
- Three have grown into additional tissues and/or have spread to more distant lymph nodes
- Four have undergone metastasis
Peritoneal Mesothelioma:
- Nausea and/or vomiting
- Abdominal pain
- Diarrhea
- Constipation
- Swelling of the abdomen
- Unexplained weight loss
- Night sweats and/or fever
Several other digestive conditions can cause similar symptoms, including Crohn’s disease, celiac disease, irritable bowel syndrome, and colon cancer.
For peritoneal mesothelioma, there isn’t a formal staging system. One common method uses a modified version of the TNM system. To classify the tumor size, this system uses the peritoneal cancer index (PCI), which is determined by scoring the amount of cancer present in each of the 13 different regions of the abdomen for a maximum score of 39.
These are the stages:
- One has a PCI score of 10 or less
- Two have a PCI score of 11 to 30
- Three have a PCI of 31 or higher and/or spread to lymph nodes or distant organs
Mesothelioma Cancer Risk Factors Plus Diagnosis Processes To Know
Asbestos is so chemically stable that even stomach acid can’t destroy it, and the fibers can embed themselves into the digestive tract. They may work their way through into the surrounding peritoneum. The element is strongly associated with Mesothelioma development, but scientists are still working to understand exactly how the mineral causes cancer.
Any foreign substance in the body naturally provokes an inflammatory response, and asbestos does so in the mesothelium. However, it’s such a stable mineral that the body isn’t able to destroy it. A stronger and stronger immune response occurs as the body attempts to get rid of the asbestos. This inflammation can eventually lead to scarring, resulting in lung disease.
The lung disease is known asbestosis in this case. In addition, it can cause damage to the DNA of cells, which has the potential to lead to cancer. Although asbestos exposure is most strongly linked to mesothelioma, it can also cause other types of cancer, including lung cancer, to be precise. It takes many years for asbestos exposure to lead to mesothelioma.
This period, known as the latency period, can be 20 to 40 years or even longer, depending on various factors. Diagnosing mesothelioma generally involves several steps, including imaging studies, a biopsy, and sometimes blood tests. Collaboration between oncology, radiology, and surgery is necessary to confirm a mesothelioma diagnosis.
Imaging Studies
For pleural mesothelioma, the diagnostic process often starts with a chest X-ray. This test is useful because it can detect several different types of issues in the lungs, allowing the doctor to narrow in on the diagnosis. For peritoneal mesothelioma, the first imaging study is often a CT scan of the abdomen. A CT scan also uses X-rays, but the images are more detailed.
This allows the doctor to look for various issues in the abdomen. Pleural mesothelioma patients may have a chest CT scan, often after concerning findings on a chest X-ray. Additional imaging studies may also be useful, such as an MRI. Doctors may also order a PET scan, which uses a tracer to detect cancer cells, often used to check for metastasis or cancer spread.
Biopsy
The definitive diagnosis of mesothelioma requires a biopsy. This is a small sample of tissue that’s examined in the laboratory to determine whether there are cancer cells present and, if so, what type. For Pleural Mesothelioma, the most common way to obtain the biopsy is through a minor surgical procedure called a thoracoscopy.
Effectively, a thoracic surgeon inserts an instrument through small incisions in the chest wall. Peritoneal Mesothelioma is commonly obtained during a laparoscopy, which involves inserting a scope through small incisions in the abdominal wall. There are other ways that the biopsy may be performed. Sometimes, the sample can be obtained using a needle through the skin.
In other cases, a sample of fluid obtained from a pleural effusion (buildup of fluid around the lungs) or ascites (buildup of fluid in the abdomen) may contain enough cancer cells for a pathologist to analyze.
Blood Tests (Immunochemistry)
A series of blood tests may be used to confirm the diagnosis. These check for biomarkers, which are certain proteins in the blood. Different proteins are associated with different types of cancer. These blood tests are not accurate enough to diagnose mesothelioma independently, but they can help distinguish different types of cancer to ensure that the diagnosis is accurate.
Mesothelioma Cell Types
Another important factor in diagnosing mesothelioma is the cell type of the cancer. There are three main mesothelial cell types:
- Epithelioid: The cells of this type are more regularly shaped and tend to form discrete sheets or clumps. This cell type is generally the easiest to treat and carries the best prognosis.
- Sarcomatoid: These cells are more irregularly shaped. They tend to be longer and tapered at both ends, which contributes to their tendency to spread easily. This cell type is the most difficult to treat.
- Biphasic: Tumors of this type have characteristics that are intermediate between the other two types. A patient’s cancer cell type significantly impacts prognosis and treatment options. For example, to be precise, only patients with epithelioid tumors are candidates for certain types of tumor-removing surgery.
Mesothelioma Prognosis And Treatment Options
Mesothelioma is a very aggressive cancer. Without treatment, the average life expectancy is about four to six months. For those who receive treatment, pleural mesothelioma patients have a median survival of 15 to 22 months, depending on the stage of cancer at the time of diagnosis.
For peritoneal mesothelioma patients who receive CRS-HIPEC (a combination of surgery and chemotherapy), median survival rates of 34 to 92 months have been reported. Although the prognosis for this cancer tends to be relatively poor overall, treatments available can potentially extend life for some patients.
Pleural Mesothelioma Treatment
- Tumor-removing surgery may be used to try to remove as much cancer tissue as possible. Options include extrapleural pneumonectomy and pleurectomy, and decortication. This is only an option for patients with cancers in their early stages.
- Chemotherapy may be given before, during, or after a surgical procedure. It may be delivered specifically into the thoracic cavity during surgery or administered to the whole body through an IV.
- Some patients receive radiation therapy, often given after surgery, to help kill any remaining cancer cells. A newer treatment option is immunotherapy. This treatment modality uses the patient’s immune system to target and destroy the cancer cells. Two options are currently FDA-approved for pleural mesothelioma patients.
- One is a drug called Keytruda, and the other is a combination of Opdivo and Yervoy. At this time, these medications are only approved for specific pleural mesothelioma patients.
- A new device called tumor-treating fields (TTF) was FDA-approved in 2019 to treat patients who aren’t eligible for surgery. This device uses electrical currents passed through the skin to interfere with cancer cells’ ability to grow and divide.
Peritoneal Mesothelioma Treatment
For peritoneal mesothelioma, the most effective treatment modality is a combination of surgery and intraoperative chemotherapy, known as cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC). Studies have found that this treatment can extend life expectancy from an average of about four months to between 34 and 92 months.
Although the procedure carries risks and causes significant side effects, it allows many patients to have a few more years with their family and friends. Equally important, patients not eligible for CRS-HIPEC may be treated using systemic chemotherapy, although this is not nearly as effective.
Palliative Treatment For Mesothelioma
By all means, Palliative Care focuses on quality of life rather than length of life. Some patients are not eligible for life-extending treatment. In contrast, others choose to receive only palliative care because they would rather focus on enjoying their remaining time with loved ones rather than endure the side effects of aggressive treatments.
Some palliative treatment options may include:
- Thoracentesis drains excess fluid from around the lungs
- Paracentesis to drain excess fluid from the abdomen
- Pleurodesis, which causes the two layers of the pleura to adhere to each other in order to prevent repeated fluid buildup around the lungs
- Palliative surgery or chemotherapy to shrink tumors that are causing significant symptoms
Mesothelioma is rare cancer, and many doctors have seen few if any, cases. Many patients choose to be treated at a cancer center for access to specialists with experience in treating mesothelioma. The National Cancer Institute has a database of cancer centers that may be helpful as you’re considering where to seek treatment.
Clinical Trials
While current treatments can extend life for many mesothelioma patients, cancer research continues to develop new treatments and better combinations of the existing treatments.
- Immunotherapy – While two types of immunotherapy are now FDA-approved for treating certain mesothelioma patients, researchers hope to develop better forms of this treatment.
- Photodynamic therapy (PDT) – This uses a drug that’s activated by light in order to kill cancer cells. During surgery, the surgeon shines the light of the correct wavelength to activate the medication. PDT is currently used for certain cancers, and researchers are looking at whether it might be effective for mesothelioma.
- Gene therapy – This cancer treatment uses modified viruses to insert particular genes into cancer cells, making them easier to kill.
Some mesothelioma patients enroll in a clinical trial, a research study of a new treatment (or a new combination of existing treatments). Being part of a mesothelioma clinical trial might give you access to a cutting-edge treatment that’s not yet available otherwise. However, there are also other tradeoffs to consider. Consider discussing clinical trials with your oncologist.
The General Mesothelioma Treatment Cost
The cost of treatment for this cancer can be significant. Even for Medicare or private insurance patients, the deductibles and copays can quickly add up. Some patients also benefit from certain complementary treatments, which insurance may not cover. With all of these costs, treatment for mesothelioma can become a financial burden for many families.
Many mesothelioma patients have this cancer because they were exposed to asbestos on the job or because a family member unknowingly brought asbestos home from work. Unfortunately, some companies failed to provide their workers with proper protective equipment, even after the dangers of asbestos were known.
In many cases, courts have held these companies accountable for the harm they caused by exposing their workers to a known carcinogen. Mesothelioma patients exposed to asbestos at work may be eligible for a financial settlement, which can help ease the financial burden of treatment.
Summary Notes:
The use of products containing asbestos was banned in the UK in 1999. But it is still found today in many buildings, including homes, public buildings, and hospitals. There are now strict guidelines about removing asbestos safely. Mesothelioma takes a long time to develop. It’s normal for people to get the first symptoms 30 to 40 years after they were first exposed to asbestos.
So people with symptoms now might have been exposed many years ago. Those working in industries that use asbestos are at higher risk of developing mesothelioma. Including shipbuilding, construction, and insulation work, but asbestos exposure could have occurred in other jobs. You can also develop Mesothelioma if you live with someone who works with asbestos.
They may have carried asbestos fibers home on their clothing, where family members could breathe them in. Some people who develop mesothelioma can’t remember coming into contact with asbestos and might not have been aware they were exposed to it. Older people have a higher risk of mesothelioma than younger people.
Of course, this is because they’re more likely to have come into contact with asbestos before the dangers were known. It’s also because it takes many years for Mesothelioma to develop.
