NORD is very grateful to W. Roy Smythe, MD, Professor and Chairman, Department of Surgery, Scott & White Hospital, Texas A&M University Health Sciences Center College of Medicine, for assistance in the preparation of this report.
Synonyms of Mesothelioma
- Malignant Mesothelioma
- No subdivisions found.
Mesothelioma is a rare form of cancer that affects the membrane that covers and protects various internal organs of the body (mesothelium). The mesothelium is composed of two layers of specialized cells known as mesothelial cells. One layer directly surrounds an organ; the other forms a protective sac around the organ. The most common form of mesothelioma affects the membrane or sac that lines the lungs (pleura). Other common sites include the membrane lining the stomach (peritoneum) and the membrane lining the heart (pericardium).
The term "cancer" refers to a group of diseases characterized by abnormal, uncontrolled cellular growth (e.g., mesothelial cells) that invades surrounding tissues and may spread (metastasize) to distant bodily tissues or organs via the bloodstream, the lymphatic system, or other means. Different forms of cancer, including mesothelioma, may be classified based upon the cell type involved, the specific nature of the malignancy, the tissues or organs affected, and the disease's clinical course. Symptoms of mesothelioma vary depending upon the location, type and stage of the cancer. Approximately 70 to 80 percent of cases of mesothelioma result from exposure to asbestos. Symptoms of mesothelioma may not appear until up to 50 years after initial exposure to asbestos. However, after symptoms began apparent, mesothelioma may rapidly progress to cause life-threatening complications.
The symptoms of mesothelioma vary depending upon the location, type and stage of the cancer. Unfortunately, early in the course of the disease, many have no symptoms, and the tumor can be difficult to see on X-ray examination.
In 85% of patients, malignant mesothelioma arises in the membranes surrounding the lungs (pleural mesothelioma. A collection of fluid around the lung, termed a pleural effusion, may be present. Symptoms may include shortness of breath, difficulty breathing (dyspnea), chest pain, or chronic cough due to fluid build up in the chest cavity (pleural effusion). When the membrane surrounding the stomach is affected (peritoneal mesothelioma), symptoms may include weight loss, stomach (abdomen) pain, nausea, bowel obstruction, low levels of circulating red blood cells (anemia), and abnormal accumulation of fluid in the space (peritoneal cavity) between the two layers of the membrane (peritoneum) that lines the stomach (ascites). When the membrane surrounding the heart is affected (pericardial mesothelioma), heart rhythm abnormalities, or low blood pressure, may occur.
Individuals with malignant mesothelioma may also experience general symptoms including fever, weakness, night sweats, weight loss, and a general feeling of ill health (malaise).
The tumor eventually spreads locally to affect the ribs, surrounding muscles and diaphragm. As the disease progresses, the esophagus, stomach and lymph nodes may become affected. Although it is usually later in the course of the disease, mesothelioma can spread to affect any area of the body.
In approximately 15 percent of patients, malignant mesothelioma arises in the membrane lining the stomach. In rare cases, malignant mesothelioma arises in the lining surrounding the heart. In extremely rare cases, mesothelial tissue lining the testicles can give rise to malignant mesothelioma. This tissue is part of the peritoneal mesothelium that extends into the scrotum.
Approximately 70 to 80 percent of individuals with malignant mesothelioma have a significant history of asbestos exposure making it the major associated risk factor for the development of malignant mesothelioma. Asbestos is a fibrous material that is resistant to fire, resulting in its use as insulation and in fire safety products. Asbestos was also used in the production of a wide variety of products including brake linings, roofing products, floor tiles, and cement. Asbestos production and use peaked during the 1930s-1960s and slowly tapered off during the 1970s. Most use of asbestos stopped after 1989. Asbestos is associated with the development of mesothelioma when asbestos fibers are inhaled or swallowed and attach to tissues lining the respiratory and/or digestive tracts. Some individuals with limited exposure to asbestos have developed mesothelioma. Others who are heavily exposed to asbestos do not develop mesothelioma.
In individuals who develop malignant mesothelioma without asbestos exposure the cause is unknown. Researchers speculate that genetic and immunologic abnormalities, environmental exposures, and/or other factors may play contributing roles in causing specific types of cancer such as mesothelioma.
Additional causes of non-asbestos related malignant mesothelioma have been suggested. A volcanic mineral, known as zeolite, has been linked to an increased incidence of mesothelioma in the Anatoli region of Turkey. Zeolite is chemically related to asbestos.
According to researchers, simian virus 40 (SV40) may play a role in the development of some cases of malignant mesothelioma although this is controversial. The exact link or relationship between the simian virus 40 and mesothelioma is unknown. More research is necessary to determine SV40's role in this disease.
Mesothelioma can affect individuals of any age although it occurs most often in individuals 50 years or older. Men are affected more often than women. Approximately 4,000 new cases of mesothelioma are diagnosed in each year in the United States, and many more may be misdiagnosed or under-reported. The peak incidence in the United States is predicted to occur in this decade. As stated above, individuals with a history of asbestos exposure are at greatest risk for this disease.
The lining of the stomach (peritoneum) is the second most common site for mesothelioma and accounts for approximately 15 percent of all cases. Approximately 250 new cases of peritoneal mesothelioma occur every year in the United States.
Symptoms of the following disorders can be similar to those of mesothelioma. Comparisons may be useful for a differential diagnosis:
Other malignant forms of cancer may be confused with mesothelioma including adenocarcinoma, which may arise in the lungs or other areas and spread to the lining of the chest (pleura). Forms of lymphoma, myeloma, thymoma, and leukemia may also have similar symptoms to mesothelioma. Pneumonia may mimic some of the early signs of mesothelioma. Pulmonary fibrosis, pulmonary embolism, lung infections and other lung diseases may need to be differentiated from mesothelioma.
A diagnosis of mesothelioma is made based upon a thorough clinical evaluation, a detailed patient history, characteristic symptoms and physical findings, a variety of specialized tests including chest x-rays and tests that determine lung function. Specialized imaging techniques may also be used to help evaluate the size, placement, and extension of the mesothelioma. Such imaging techniques may include computerized tomography (CT) scanning, magnetic resonance imaging (MRI), and positron emission tomography (PET) scan. During CT scanning, a computer and x-rays are used to create a film showing cross-sectional images of certain tissue structures. An MRI uses a magnetic field and radio waves to produce cross-sectional images of particular organs and bodily tissues. During a PET scan, three-dimensional images are produced that reflect the brain's chemical activity.
A diagnosis of mesothelioma will usually need to be confirmed by removal of, and microscopic examination (biopsy) of, affected tissue. Different types of biopsies (e.g., transthoracic needle biopsy, needle-assisted thoracoscopy) may be performed. Needle biopsy of mesothelioma may be performed by a radiologist using either ultrasound or a CT scan to guide placement of the needle. During video thoracoscopy, a thin tube with a built-in camera (thoracoscope) is inserted into the chest through a small surgical cut (incision) allowing a physician to view the lungs and obtain tissue samples. This is usually a formal operative procedure performed in an operating room, or similar setting, and may require a general anesthetic with a temporary breathing tube. A similar procedure called a laparoscopy may be performed to view the peritoneum lining the inside of the stomach. Only in rare cases, will a needle biopsy, a thoracoscopy, or laparoscopy not obtain enough tissue for diagnosis. In these cases, more invasive techniques such as a thoracotomy or laparotomy (operative procedures with larger incisions), may be performed to assist in the diagnosis of mesothelioma.
When an individual is diagnosed with mesothelioma, assessment is also required to determine the extent or "stage" of the disease. Staging is important to help determine how far the disease has spread, characterize the potential disease course, and determine appropriate treatment approaches. Some of the same diagnostic tests described above may be used in staging mesothelioma. In addition, even when the disease is limited to the chest, a physician may need to perform a procedure called a mediastinoscopy (similar to other techniques above) to take biopsies of lymph nodes in the central region (mediastinum) of the chest, or laparoscopy to rule out spread into the abdomen as radiographic tests may miss disease in these areas.
The therapeutic management of individuals with malignant mesothelioma may require the coordinated efforts of a team of medical professionals, such as physicians who specialize in the diagnosis and treatment of cancer (medical oncologists), specialists in the use of radiation to treat cancer (radiation oncologists), surgeons, oncology nurses, and other specialists (depending upon the primary tumor site).
Specific therapeutic procedures and interventions may vary, depending upon numerous factors, such as primary tumor location, extent of the primary tumor (stage), and degree of malignancy (grade); whether the tumor has spread to lymph nodes or distant sites; individual's age and general health; and/or other elements. Decisions concerning the use of particular interventions should be made by physicians and other members of the health care team in careful consultation with the patient, based upon the specifics of his or her case; a thorough discussion of the potential benefits and risks; patient preference; and other appropriate factors. As this is an unusual disease, patients should give strong consideration to seeking the care of someone who is a specialist or experienced in this area.
In many individuals with mesothelioma, standard therapy includes surgical removal of all or a portion of the malignancy and affected tissue. Surgical removal of the lining of the chest (pleura) may be performed in some cases of pleural mesothelioma (pleurectomy). Another procedure, known as an extrapleural pneumonectomy involves surgical removal of the pleura, pericardium, diaphragm, and the entire affected lung. Surgical removal of the peritoneum and surrounding tissue may be performed in cases of peritoneal mesothelioma.
In addition, based upon primary tumor site, size, and other factors, recommended therapy may often include postoperative radiation to help treat known or possible residual disease. If initial surgery is not an option due to the specific location and/or progression of the malignancy, therapy may include radiation alone. Radiation therapy preferentially destroys or injures rapidly dividing cells, primarily cancerous cells. However, some healthy cells (e.g., hair follicles, bone marrow, etc.) may also be damaged, leading to certain side effects. Thus, during such therapy, the radiation is passed through diseased tissue in carefully calculated dosages to destroy cancer cells while minimizing exposure and damage to normal cells. Radiation therapy works to destroy cancer cells by depositing energy that damages their genetic material, preventing or slowing their growth and replication. Various types of radiation may be used--again, depending on cancer type, location, stage and grade, prior treatments.
For some affected individuals, particularly those who have locally advanced, metastatic, or recurrent disease, or those unable to tolerate more aggressive approaches, therapy with certain anticancer drugs (chemotherapy) may also be recommended. For some patients, some combination of two or all three modalities may be considered (surgery, radiation, chemotherapy). Physicians may recommend combination therapy with multiple chemotherapeutic drugs that have different modes of action in destroying tumor cells and/or preventing them from multiplying.
In February 2004, the U.S. Food and Drug Administration (FDA) approved the orphan drug pemetrexed disodium (Alimta) used in combination with cisplatin for the treatment of individuals with malignant pleural mesothelioma. Alimta is distributed by Eli Lilly and Company. For more information, contact:
Eli Lilly and Company
Lilly Corporate Center
Indianapolis, Indiana 46285 USA
Some treatment for individuals with mesothelioma may help to reduce symptoms and ease pain. Such therapies include procedures known as thoracentesis and paracentesis to drain fluid that may accumulate in the chest or stomach. During a thoracentesis, a needle or small tube (catheter) is inserted into the chest to remove excessive fluid. During a paracentesis, a small, thin tube is inserted into the stomach.
In June of 2008 MolMed, a Milan-based company, was just granted Orphan Drug designation by the European Commission for its vascular targeting agent ARENEGYR in the treatment of malignant pleural mesothelioma (MPM).
Information on current clinical trials is posted on the Internet at www.clinicaltrials.gov. All studies receiving U.S. government funding, and some supported by private industry, are posted on this government web site.
For information about clinical trials being conducted at the NIH Clinical Center in Bethesda, MD, contact the NIH Patient Recruitment Office:
Tollfree: (800) 411-1222
TTY: (866) 411-1010
For information about clinical trials sponsored by private sources, contact:
Organizations related to Mesothelioma
Please note that some of these organizations may provide information concerning certain conditions potentially associated with this disorder.
DeVita Jr VT, et al, eds. Cancer Principles and Practice of Oncology. 5th Ed. New York, NY: J.B. Lippincott Company; 1997:1853-78.
Raghavan D., ed. Textbook of Uncommon Cancer, 2nd ed. New York, NY: John Wiley & Sons, Ltd; 1999:523-35.
Hassan R, et al., Current treatment options and biology of peritoneal mesothelioma: meeting summary of the first NIH peritoneal mesothelioma conference. Ann Oncol. 2006 [Epub ahead of print].
Ceresoli GL, et al., Phase II study of pemetrexed plus carboplatin in malignant pleural mesothelioma. J Clin Oncol. 2006;20:1443-8.
Pavlakis N, Vogelzang NJ. Ranpirase - an antitumour ribonuclease: its potential role in malignant mesothelioma. Expert Opin Biol Ther. 2006;6:391-9.
Vogelzang NJ, et al. New agents in the management of advanced mesothelioma. Semin Oncol. 2005;32:336-50.
Portalone L, et al. Epirubicin and gemcitabine as first-line treatment in malignant pleural mesothelioma. Tumori. 2005;91:15-8.
Wang ZJ, et al., Malignant pleural mesothelioma: evaluation with CT, MR imaging, and PET. Radiographics. 2004;24:105-19.
Altin R, et al., Localized benign pleural mesothelioma: a case report. Monaldi Arch Chest Dis. 2003;59:-166-8.
Janne PA., Chemotherapy for malignant mesothelioma. Clin Lung Cancer. 2003;5:98-106.
Smythe W. Current therapy for malignant mesothelioma. Curr Oncol Rep. 2002;4:305-13.
Daniel J, Smythe W. Gene therapy of cancer. Seminars in Surgical Oncology. 2003;21:196-204.
Ahamad A, et al. Promising early local control of malignant pleural mesothelioma following postoperative intensity modulated radiotherapy (IMRT) to the chest. Cancer J. 2003;9:476-84.
Gordon GJ, et al., Detection and quantification of SV40 large T0-antigen DNA in mesothelioma tissues and cell lines. Oncology Reports. 2002;9:631-4.
Zellos L, Sugarbaker DJ, Current surgical management of malignant pleural mesothelioma. Curr Oncol Rep. 2002;4:354-60.
Green MR, The evolving role of gemcitabine and pemetrexed (Alimta) in the management of patients with malignant mesothelioma. Clin Lung Cancer. 2002;3:S26-9.
Ho L, et al., Malignant pleural mesothelioma. Current Treat Res. 2001;105:327-73.
Pass HI, Malignant pleural mesothelioma: surgical roles and novel therapies. Clin Lung Cancer. 2001;3:102-17.
Knudson A, Asbestos and mesothelioma: genetic lessons from a tragedy. Proc Natl Acad Sci USA. 1995;92:10819-10820.
FROM THE INTERNET
McKusick VA., ed. Online Mendelian Inheritance in Man (OMIM). Baltimore. MD: The Johns Hopkins University; Entry No:156240; Last Update:1/15/2004.
Available at: http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=156240
Tan WW. Mesothelioma. eMedicine Journal. 2002;3:10pp.
Available at: http://www.emedicine.com/med/topic1457.htm
Dee EK. Mesothelioma, Malignant. eMedicine Journal. 2001;3:11pp.
Available at: http://www.emedicine.com/radio/topic449.htm
National Cancer Institute. Cancer Facts. Mesothelioma: Questions and Answers. Last Update: 05/13/2002. 5pp.
Available at: http://cis.nci.nih.gov/fact/6_36.htm
American Lung Association. Mesothelioma Fact Sheet. April 2003.
Available at: http://www.lungusa.org/diseases/mesothelioma.ht
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