What is mesothelioma?
Mesothelioma is a kind of cancer that occurs in the thin layer of tissue that covers most internal organs (mesothelium). This is an aggressive and terminal form of cancer. There are treatments for this cancer, but for many people with mesothelioma, a cure is not possible.
Physicians divide this cancer into different types based on the part of the mesothelium unnatural. Mesothelioma most often affects the tissue that surrounds the lungs (pleura). This type is called pleural mesothelioma. Other rarer types of mesothelioma affect the tissue in the abdomen (peritoneal mesothelioma), around the heart, and the testicles.
Types of mesothelioma
There are four types of malignant mesothelioma depending on the location of the tumor:
- Pleural mesothelioma (lungs)
- Peritoneal (abdomen) mesothelioma
- Pericardial (heart) mesothelioma
- Testicular mesothelioma
Symptoms of mesothelioma
The signs and symptoms of mesothelioma vary depending on the site of cancer.
Pleural mesothelioma, which affects the tissue around the lungs, causes signs and symptoms that may include:
- Chest pain
- Painful cough
- Difficulty breathing
- Unusual lumps of tissue under the skin of the chest
- Unexplained weight loss
Peritoneal mesothelioma, which occurs in the tissue of the abdomen, causes signs and symptoms that may include:
- Abdominal pain
- Abdominal swelling
- Unexplained weight loss
Other forms of mesothelioma
The signs and symptoms of other kinds of this cancer are unclear, as these forms of the disease are very rare.
- Pericardial mesothelioma, which affects the tissue around the heart, can cause signs and symptoms such as shortness of breath and chest pains.
- Tunica vaginalis mesothelioma, which affects the tissue surrounding the testicles, may first be perceived as swelling or a mass in a testicle.
Causes of mesothelioma
Overall, cancer begins when a series of changes (mutations) occur in the DNA of a cell. DNA contains the commands that tell a cell what to do. Mutations tell the cell to grow and multiply uncontrollably. The abnormal cells build up and form a tumor.
It is not clear what causes the initial genetic changes that lead to this cancer, though researchers have identified factors that may increase the risk. Cancers are likely to form due to an interaction between many factors, such as inherited conditions, your environment, your health conditions, and your lifestyle choices.
The main risk factor for mesothelioma are:
- Most mesotheliomas are believed to be related to asbestos exposure. Asbestos is a mineral that happens naturally in the environment. Asbestos fibres are strong and resistant to heat, making them valuable in a wide variety of applications, such as separation, brakes, shingles, flooring, and many other products.
- When asbestos breaks, such as during the extraction process or when removing asbestos insulation, dust can be created. If the dust is gasped or ingested, the asbestos fibres will settle in the lungs or stomach, where they can cause irritation that can lead to mesothelioma. It is not understood exactly how this happens. Mesothelioma can take 20 to 60 years or more to develop after asbestos exposure.
- Most people exposed to asbestos never develop mesothelioma. This indicates that other issues may be involved in determining whether someone gets mesothelioma. For example, you could inherit a predisposition to cancer, or some other condition could increase your risk.
Factors that can increase the risk of mesothelioma contain:
- Personal history of asbestos exposure: If you have been directly exposed to asbestos fibres at work or home, your risk of mesothelioma increases considerably.
- Live with someone who works with asbestos: People who are exposed to asbestos can carry the fibres home on their skin and clothing. Exposure to these stray fibres over many years can put other people in the home at risk for mesothelioma. People who work with high levels of asbestos can reduce the risk of bringing asbestos fibres home by showering and changing clothes before leaving work.
- Family history of mesothelioma: If your parent, brother, or child has mesothelioma, you may be at higher risk for this disease.
- Radiation therapy to the chest: If you received radiation therapy for breast cancer, you may have an increased risk of this cancer.
Diagnosis of mesothelioma
If you have signs and symptoms that could indicate mesothelioma, your doctor will perform a physical exam to check for lumps or other unusual signs. Your doctor may order imaging scans, such as a chest x-ray and computed tomography (CT) scan of your chest or abdomen, to look for abnormalities. Based on the findings, you may undergo further tests to determine if mesothelioma or another disease is causing your symptoms.
Biopsy, a procedure to remove a small piece of tissue for laboratory examination, is the only way to determine if you have mesothelioma. Depending on which area of your body is affected, your doctor selects the biopsy procedure that is right for you.
- Insert a needle through the skin. The doctor may remove fluid or a piece of tissue with a fine needle that is inserted through the skin of the chest or abdomen.
- Collection of a tissue sample during surgery. A sample of fluid or tissue may be collected during operation. The surgeon may make a small incision and insert a tube with a video camera to view the inside of your chest or abdomen. Special tools can be passed to finish the tube to collect a tissue sample.
- The tissue sample is examined under a microscope to see if the abnormal tissue is mesothelioma and what types of cells are involved. The sort of cancer you have determines your treatment plan.
Determine the extent of the cancer
Once your mesothelioma is confirmed, your doctor may mention additional tests to find out if your cancer has spread to your lymph nodes or other areas of your body.
The tests may include:
- CT scans of the chest and abdomen
- Magnetic resonance imaging (MRI)
- Positron emission tomography (PET)
Your doctor determines which tests are right for you. Not all people need all tests. Your doctor uses the information from these tests to stage cancer. The stages of pleural mesothelioma are indicated by Roman numerals ranging from I to IV. A lower number means that the cancer is more likely to be in the area around the lungs, and a higher number means that cancer has spread to other areas of the body.
The staging system for cancer continues to evolve and becomes more complex as doctors improve their diagnosis and treatment of cancer. Your doctor uses the stage of cancer to select the right treatments for you. The formal stages are not available for other types of mesothelioma.
Treatment of mesothelioma
The treatment you undergo for this cancer rests on your health and certain aspects of your cancer, such as its stage and location.
Unluckily, It is often an aggressive disease, and for most people, a cure is not possible. This cancer is usually diagnosed at a progressive stage when cancer cannot be detached by surgery. Instead, your doctor can work to control your cancer so that you feel more comfortable.
Discuss the goals of treatment with your doctor. Some people want to do everything they can to treat their cancer, even if it means enduring side effects for a small chance of improvement. Others prefer treatments that make them feel comfortable so they can live as long as possible free of symptoms.
Surgeons work to eliminate this cancer when it is diagnosed at an early stage. In some cases, this can cure cancer. Most of the time, all of cancer cannot be removed. In this situation, surgery can help reduce the signs and symptoms caused by the spread of this cancer in your body.
Surgical options may include:
- Surgery to decrease fluid build-up. Pleural mesothelioma can cause fluid to build up in the chest, causing shortness of breath. Surgeons insert a tube or catheter into your chest to gutter the fluid. Doctors may also inject medicine into your chest to keep the fluid from coming back (pleurodesis).
- Surgery to eliminate the tissue around the lungs. Surgeons can remove the tissue that lines the ribs and lungs (pleurectomy). This procedure will not cure this disease, but it can relieve the signs and symptoms.
- Surgery to eliminate a lung and surrounding tissue. Removal of the affected lung and surrounding tissue can alleviate the signs and symptoms of pleural mesothelioma. If you will receive radiation therapy to the chest after surgery, this procedure also allows doctors to use higher doses, as they won’t have to worry about protecting your lung from harmful radiation.
- Peritoneal mesothelioma surgery. This is sometimes preserved with surgery to eliminate as much cancer as possible. Chemotherapy can be used before or after surgery.
Chemotherapy uses chemicals to kill cancer cells. Systemic chemotherapy travels throughout the body and can reduce or slow the growth of this cancer that cannot be removed by surgery. Chemotherapy can also be used before surgery (neoadjuvant chemotherapy) to make the operation easier or after surgery (adjuvant chemotherapy) to reduce the chance that cancer will come back.
Chemotherapy drugs can also be heated and given directly into the abdominal cavity (intraperitoneal chemotherapy), in the case of peritoneal mesothelioma.
Radiation therapy focuses on high-energy rays from sources such as X-rays and protons to a specific point or points on your body. Radiation can be used after surgery to kill any outstanding cancer cells. It can also help reduce the signs and symptoms of progressive cancer in situations where surgery is not an option.
In certain situations, other treatments can be used to treat this cancer. Other treatments include:
- Immunotherapy: Immunotherapy uses your immune system to fight cancer. Your body’s disease-fighting immune system may not attack your cancer because cancer cells make proteins that blunt immune system cells. Immunotherapy works by interfering with this process. This treatment might be an option if other treatments don’t work.
- Targeted therapy: Targeted therapy uses drugs that target specific vulnerabilities in cancer cells. These drugs are not commonly used to treat this disease, but your doctor may recommend targeted therapy based on the results of DNA testing of the tumor.
Clinical trials are studies of new methods of treating this disease. People with this cancer may opt for a clinical trial for a chance to test new types of treatment. However, a cure is not guaranteed. Carefully consider your treatment options and talk to your doctor about the quantifiable trials you have open. Taking part in a clinical trial can help doctors better understand how to treat this cancer in the future.
Currently, clinical trials are investigating several new approaches to the treatment of this cancer, including new targeted therapy drugs and new approaches to immunotherapy.
Treatment for other types of mesothelioma
Pericardial mesothelioma and tunica vaginalis mesothelioma are very rare. Early-stage cancer can be removed by surgery. However, doctors have yet to determine the best way to treat late-stage cancers.
Reducing your exposure to asbestos can lower your risk of this disease. Find out if you work with asbestos. Most societies with this cancer were exposed to asbestos fibres at work. Workers who may encounter asbestos fibres include:
- Asbestos miners
- Filters for pipes
- Shipyard workers
- Demolition workers
- Brake mechanics
- Selected military personnel
- Home remodelers
- Ask your employer if you are at risk for asbestos exposure at work.
- Follow your employer’s safety rules
- Follow all safety precautions in your workplace, such as wearing protective gear. You may also need to shower and change your work clothes before taking a lunch break or going home.
As pleural mesothelioma feasts in the chest, it puts pressure on structures in that area. This can cause complications, such as:
- Difficulty breathing
- Chest pain
- Difficulty to swallow
- Pain caused by heaviness on the nerves and spinal cord
A buildup of fluid in the chest (pleural effusion), which can compress the nearby lung and make it difficult to breathe.
Departments to consult for this condition
- Department of oncology