Mesothelioma is a rare form of cancer primarily caused by asbestos exposure. There is a higher incidence of mesothelioma among U.S. Navy personnel, shipyard workers, etc. due to asbestos exposure on Navy ships. In addition, relatives members and others closely associated to those exposed to asbestos may also be at risk (for example the wife who washed her husband's work clothes). The cancer typically has a latency period of 20 to 50 years.
The mesothelium has different names, depending on its location in the body. The peritoneum is the mesothelial tissue that covers most of the organs in the abdominal cavity. The pleura is the membrane that surrounds the lungs and lines the wall of the chest cavity. The pericardium covers and protects the heart. The mesothelial tissue surrounding the male internal reproductive organs is called the tunica vaginalis testis. The tunica serosa uteri covers the internal reproductive organs in women.
Symptoms of mesothelioma may not appear until 30 to 50 years after exposure to asbestos. Shortness of breath and pain in the chest due to an accumulation of liquid in the pleura are often symptoms of pleural mesothelioma. Symptoms of peritoneal mesothelioma include weight loss and abdominal pain and swelling due to a buildup of liquid in the abdomen. Other symptoms of peritoneal mesothelioma may include bowel obstruction, blood clotting abnormalities, anemia, and fever. If the cancer has spread beyond the mesothelium to other parts of the body, symptoms may include pain, trouble swallowing, or swelling of the neck or face. These symptoms may be caused by mesothelioma or by other, less serious conditions. It is important to see a doctor about any of these symptoms. Only a doctor can make a diagnosis.
Diagnosing mesothelioma is often difficult, because the symptoms are similar to those of a number of other conditions. Diagnosis begins with a review of the patient’s medical history, including any history of asbestos exposure. A complete physical examination may be performed, including x-rays of the chest or abdomen and lung function tests. A CT (or CAT) scan or an MRI may also be useful. A CT scan is a series of detailed pics of areas inside the body created by a computer linked to an x-ray machine. In an MRI, a powerful magnet linked to a computer is used to make detailed pics of areas inside the body. These pics are viewed on a monitor and can also be printed.
A biopsy is needed to confirm a diagnosis of mesothelioma. In a biopsy, a surgeon or a medical oncologist (a doctor who specializes in diagnosing and treating cancer) removes a sample of tissue for examination under a microscope by a pathologist. A biopsy may be done in different ways, depending on where the abnormal area is located. If the cancer is in the chest, the doctor may perform a thoracoscopy. In this procedure, the doctor makes a little cut through the chest wall and puts a narrow, lighted tube called a thoracoscope in to the chest between two ribs. Thoracoscopy allows the doctor to look inside the chest and receive tissue samples. If the cancer is in the abdomen, the doctor may perform a peritoneoscopy. To receive tissue for examination, the doctor makes a little opening in the abdomen and inserts a special tool called a peritoneoscope in to the abdominal cavity. If these procedures do not yield tissue, more extensive diagnostic surgery may be necessary.
If the diagnosis is mesothelioma, the doctor will need to learn the stage (or extent) of the . Staging involves more tests in a careful attempt to find out whether the cancer has spread and, if so, to which parts of the body. Knowing the stage of the helps the doctor plan treatment.
Mesothelioma is described as localized if the cancer is found only on the membrane surface where it originated. It is classified as advanced if it's spread beyond the original membrane surface to other parts of the body, such as the lymph nodes, lungs, chest wall, or abdominal organs.
Treatment for mesothelioma is contingent on the location of the cancer, the stage of the , and the patient’s age and general health. Standard treatment options include surgery, radiation therapy, and chemotherapy. Sometimes, these treatments are combined.
Chemotherapy is the use of anticancer drugs to kill cancer cells throughout the body. Most drugs used to treat mesothelioma are given by injection in to a vein (intravenous, or IV). Doctors are also studying the effectiveness of putting chemotherapy directly in to the chest or abdomen (intracavitary chemotherapy).
Surgery is a common treatment for mesothelioma. The doctor may remove part of the lining of the chest or abdomen and a number of the tissue around it. For cancer of the pleura (pleural mesothelioma), a lung may be removed in an operation called a pneumonectomy. Sometimes part of the diaphragm, the muscle below the lungs that helps with breathing, is also removed.
Radiation therapy, also called radiotherapy, involves the use of high-energy rays to kill cancer cells and shrink tumors. Radiation therapy affects the cancer cells only in the treated area. The radiation may come from a machine (external radiation) or from putting materials that produce radiation through narrow plastic tubes in to the area where the cancer cells are found (internal radiation therapy).
To relieve symptoms and control pain, the doctor may use a needle or a narrow tube to drain liquid that has built up in the chest or abdomen. The procedure for removing liquid from the chest is called thoracentesis. Removal of liquid from the abdomen is called paracentesis. Drugs may be given through a tube in the chest to prevent more liquid from accumulating. Radiation therapy and surgery may also be helpful in relieving symptom