Malignant mesothelioma (me-zoe-thee-lee-O-muh) is a type of cancer that occurs in the thin layer of tissue that covers the majority of your internal organs (mesothelium). Mesothelioma is an aggressive and deadly form of cancer. Mesothelioma treatments are available, but for many people with mesothelioma, a cure is not possible. Doctors divide mesothelioma into different types based on what part of the mesothelium is affected. Mesothelioma most often affects the tissue that surrounds the lungs (pleura). This type is called pleural mesothelioma. Other, rarer types of mesothelioma affect tissue in the abdomen (peritoneal mesothelioma), around the heart and around the testicles. Mesothelioma doesn't include a form of noncancerous (benign) tumor that occurs in the chest and is sometimes called benign mesothelioma or solitary fibrous tumor. Symptoms: Signs and symptoms of mesothelioma vary depending on where the cancer occurs. Pleural mesothelioma, which affects the tissue that surrounds the lungs, causes signs and symptoms that may include: chest pain under the rib cage Painful coughing Shortness of breath Unusual lumps of tissue under the skin on your chest Unexplained weight loss Peritoneal mesothelioma, which occurs in tissue in the abdomen, causes signs and symptoms that may include: Abdominal pain Abdominal swelling Lumps of tissue in the abdomen Unexplained weight loss Other forms of mesothelioma Signs and symptoms of other types of mesothelioma are unclear, since these forms of the disease are very rare. Pericardial mesothelioma, which affects tissue that surrounds the heart, can cause signs and symptoms such as breathing difficulty and chest pains. Mesothelioma of tunica vaginalis, which affects tissue surrounding the testicles, may be first detected as swelling or a mass on a testicle. Causes : In general, cancer begins when a series of genetic mutations occur within a cell, causing the cell to grow and multiply out of control. It isn't clear what causes the initial genetic mutations that lead to mesothelioma, though researchers have identified factors that may increase the risk. It's likely that cancers form because of an interaction between many factors, such as inherited conditions, your environment, your health conditions and your lifestyle choices. Risk Factors : Asbestos exposure: The primary risk factor for mesothelioma Asbestos is a mineral that's found naturally in the environment. Asbestos fibers are strong and resistant to heat, making them useful in a wide variety of applications, such as in insulation, brakes, shingles, flooring and many other products. When asbestos is broken up, such as during the mining process or when removing asbestos insulation, dust may be created. If the dust is inhaled or swallowed, the asbestos fibers will settle in the lungs or in the stomach, where they can cause irritation that may lead to mesothelioma. Exactly how this happens isn't understood. It can take 20 to 40 years or more for mesothelioma to develop after asbestos exposure. Most people with years of asbestos exposure never develop mesothelioma. And yet, others with very brief exposure develop the disease. This indicates that other factors may be involved in determining whether someone gets mesothelioma or doesn't. For instance, you could inherit a predisposition to cancer or some other condition could increase your risk. Risk factors Factors that may increase the risk of mesothelioma include: Personal history of asbestos exposure. If you've been directly exposed to asbestos fibers at work or at home, your risk of mesothelioma is greatly increased. Living with someone who works with asbestos. People who are exposed to asbestos may carry the fibers home on their skin and clothing. Exposure to these stray fibers over many years can put others in the home at risk of mesothelioma. People who work with high levels of asbestos can reduce the risk of bringing home asbestos fibers by showering and changing clothes before leaving work. A family history of mesothelioma. If your parent, sibling or child has mesothelioma, you may have an increased risk of this disease. Complications : As pleural mesothelioma spreads in the chest, it puts pressure on the structures in that area. This can cause complications, such as: Difficulty breathing chest pain Difficulty swallowing Pain caused by pressure on the nerves and spinal cord Accumulation of fluid in the chest (pleural effusion), which can compress the lung nearby and make breathing difficult Diagnosis : If you have signs and symptoms that might indicate mesothelioma, your doctor will conduct a physical exam to check for any lumps or other unusual signs. Your doctor may order imaging scans, such as a chest X-ray and a computerized tomography (CT) scan of your chest or abdomen, to look for abnormalities. Based on the findings, you may undergo further testing to determine whether mesothelioma or another disease is causing your signs and symptoms. Biopsy Biopsy, a procedure to remove a small portion of tissue for laboratory examination, is the only way to determine whether you have mesothelioma. Depending on what area of your body is affected, your doctor selects the right biopsy procedure for you. Options include: Fine-needle aspiration. The doctor removes fluid or a piece of tissue with a small needle inserted into your chest or abdomen. Thoracoscopy. Thoracoscopy allows the surgeon to see inside your chest. In this procedure, the surgeon makes one or more small incisions between your ribs. A tube with a tiny video camera is then inserted into your chest cavity — a procedure sometimes called video-assisted thoracoscopic surgery (VATS). Special surgical tools allow your surgeon to cut away small pieces of tissue for testing. Laparoscopy. Laparoscopy allows the surgeon to see inside your abdomen. Using one or more small incisions into your abdomen, the surgeon inserts a tiny camera and special surgical tools to obtain a small piece of tissue for examination. Thoracotomy. Thoracotomy is surgery to open your chest between the ribs to allow a surgeon to check for signs of disease. A sample of tissue may be removed for testing. Laparotomy. Laparotomy is surgery to open your abdomen to allow a surgeon to check for signs of disease. A sample of tissue may be removed for testing. The tissue sample is analyzed under a microscope to see whether the abnormal tissue is mesothelioma and what types of cells are involved. The type of mesothelioma you have determines your treatment plan. Staging Once mesothelioma is diagnosed, your doctor orders other tests to determine the extent, or stage, of the cancer. Imaging tests that may help determine the stage of your cancer may include: CT scans of the chest and abdomen Magnetic resonance imaging (MRI) Positron emission tomography (PET) Your doctor determines which tests are more appropriate for you. Not every person needs every test. Once the extent of pleural mesothelioma is determined, a stage is assigned. Stage I mesothelioma is considered localized cancer, meaning it's limited to one portion of the lining of the chest. Stage II mesothelioma may have spread beyond the lining of the chest to the diaphragm or to a lung. Stage III mesothelioma may have spread to other structures within the chest and may involve nearby lymph nodes. Stage IV mesothelioma is an advanced cancer that has spread more extensively within the chest. Stage IV may also indicate that mesothelioma has spread to distant areas of the body, such as the brain, liver and lymph nodes elsewhere in the chest. Formal stages aren't available for other types of mesothelioma because these types are rare and aren't well-studied. Treatment : What treatment you undergo for mesothelioma depends on your health and certain aspects of your cancer, such as its stage and location. Unfortunately, mesothelioma often is an aggressive disease and for most people a cure isn't possible. Mesothelioma is usually diagnosed at an advanced stage — when it isn't possible to remove the cancer through an operation. Instead, your doctor may work to control your cancer to make you more comfortable. Discuss treatment goals with your doctor. Some people want to do everything they can to treat their cancer, even if that means enduring side effects for a small chance of an improvement. Others prefer treatments that make them comfortable so that they can live their remaining time as symptom-free as possible. Surgery Surgeons work to remove mesothelioma when it's diagnosed at an early stage. In some cases this may cure the cancer. Sometimes it isn't possible to remove all of the cancer. In those cases, surgery may help to reduce the signs and symptoms caused by mesothelioma spreading in your body. Surgical options may include: Surgery to decrease fluid buildup. Pleural mesothelioma may cause fluid to build up in your chest, causing difficulty breathing. Surgeons insert a tube or catheter into your chest to drain the fluid. Doctors may also inject medicine into your chest to prevent fluid from returning (pleurodesis). Surgery to remove the tissue around the lungs or abdomen. Surgeons may remove the tissue lining the ribs and the lungs (pleurectomy) or the tissue lining the abdominal cavity (peritonectomy). This procedure won't cure mesothelioma, but may relieve signs and symptoms. Surgery to remove as much of the cancer as possible (debulking). If all of the cancer can't be removed, surgeons may attempt to remove as much as possible. Debulking allows doctors to more accurately direct radiation treatments to relieve pain and fluid buildup caused by mesothelioma. Surgery to remove a lung and the surrounding tissue.Removing the affected lung and the tissue that surrounds it may relieve signs and symptoms of pleural mesothelioma. If you'll be receiving radiation therapy to the chest after surgery, this procedure also allows doctors to use higher doses, since they won't need to worry about protecting your lung from damaging radiation. Chemotherapy Chemotherapy uses chemicals to kill cancer cells. Systemic chemotherapy travels throughout the body and may shrink or slow the growth of a mesothelioma that can't be removed using surgery. Chemotherapy may also be used before surgery (neoadjuvant chemotherapy) to make an operation easier or after surgery (adjuvant chemotherapy) to reduce the chance that cancer will return. Chemotherapy drugs may also be heated and administered directly into the abdominal cavity (intraperitoneal chemotherapy), in the case of peritoneal mesothelioma. Using this strategy, chemotherapy drugs can reach the mesothelioma directly without injuring healthy cells in other parts of the body. This allows doctors to administer higher doses of chemotherapy drugs. Radiation therapy Radiation therapy focuses high-energy beams from sources such as X-rays and protons to a specific spot or spots on your body. Radiation may be used after surgery to kill any remaining cancer cells. It may also help reduce signs and symptoms of advanced cancer in situations where surgery isn't an option. Clinical trials Clinical trials are studies of new mesothelioma treatment methods. People with mesothelioma may opt for a clinical trial for a chance to try new types of treatment. However, a cure isn't guaranteed. Carefully consider your treatment options and talk to your doctor about what clinical trials are open to you. Your participation in a clinical trial may help doctors better understand how to treat mesothelioma in the future. Clinical trials are currently investigating a number of new approaches to mesothelioma treatment, including: Targeted therapy, which involves using drugs that attack specific abnormalities within cancer cells. Biological therapy, which uses your body's immune system to fight cancer. Gene therapy, which involves altering the genes inside the cancer cells in order to stop disease. Treatment for other types of mesothelioma Pericardial mesothelioma and mesothelioma of tunica vaginalis are very rare. Early-stage cancer may be removed through surgery. Doctors have yet to determine the best way to treat later-stage cancers, though. Your doctor may recommend other treatments to improve your quality of life. Source
