- A malignant tumor of the mesothelium. The mesothelium is the thin lining on the surface of the body cavities and the organs that are contained within them. Most mesotheliomas begin as one or more nodules that progressively grow to form a solid coating of tumor surrounding the lung, abdominal organs, or heart. Mesothelioma most commonly occurs in the chest cavity and is associated with exposure to asbestos in up to 90% of cases. It has been shown that some asbestos fibers that are inhaled quickly work their way through the lung tissue and into the chest (pleural) cavity. Asbestos fibers that are swallowed have been shown to penetrate the wall of the intestine and appear in the abdominal (peritoneal) cavity. The risk of mesothelioma increases with the intensity and duration of exposure to asbestos. It is debatable whether or not there is any safe exposure level. Mesothelioma typically does not occur for 20 to 50 years following exposure to asbestos. Some forms of asbestos, particularly crocidolite fibers, are more likely to cause mesotheliomas. There is also evidence that mesotheliomas may be caused by other agents including radiation, viruses, and man-made mineral fibers. There is no relationship to smoking. Mesothelioma is currently difficult to treat in most cases and survival beyond two years is unusual.
* * *A rare neoplasm derived from the lining cells of the pleura and peritoneum which grows as a thick sheet covering the viscera, and is composed of spindle cells or fibrous tissue which may enclose glandlike spaces lined by cuboidal cells. [mesothelium + G. -oma, tumor]
* * *me·so·the·li·o·ma .mez-ə-.thē-lē-'ō-mə, .mēz-, .mēs-, .mes- n, pl -mas also -ma·ta -mət-ə a tumor derived from mesothelial tissue (as that lining the peritoneum or pleura)
* * *n.a tumour of the pleura, peritoneum, or pericardium. The occurrence of pleural mesothelioma is often due to exposure to asbestos dust (see asbestosis), and workers in the asbestos industry who develop such tumours are entitled to industrial compensation. In other cases there is no history of direct exposure to asbestos at work, but the patients had been exposed to asbestos via the clothes of relatives who had had direct contact with asbestos, or they themselves had lived very close to an asbestos factory. There is no curative treatment for the disease, but moderately good results have occasionally been obtained from radical surgery for limited disease, from radiotherapy, and more recently from chemotherapy.
* * *meso·the·li·o·ma (mez″o-) (me″zo-the″le-oґmə) a tumor derived from mesothelial tissue (peritoneum, pleura, pericardium); both benign and malignant varieties exist. Malignant varieties are often the result of excessive exposure to asbestos.
Medical dictionary. 2011.
Look at other dictionaries:
Mesothelioma — Classification and external resources Left sided mesothelioma with mediastinal node enlargement : CT scan. ICD 10 C … Wikipedia
mesothelioma — [mes΄ō thē΄lē ō′mə] n. [< MESOTHELIUM + OMA] a tumor of the mesothelium, often malignant and thought to be caused most commonly by the inhalation of asbestos particles … English World dictionary
mesothelioma — n. a tumour of the pleura, peritoneum, or pericardium. The occurrence of pleural mesothelioma is often due to exposure to asbestos dust (see asbestosis), and workers in the asbestos industry who develop such tumours are entitled to industrial… … The new mediacal dictionary
mesothelioma — A benign (noncancerous) or malignant (cancerous) tumor affecting the lining of the chest or abdomen. Exposure to asbestos particles in the air increases the risk of developing malignant mesothelioma … English dictionary of cancer terms
mesothelioma — noun (plural mas; also mesotheliomata) Etymology: New Latin Date: circa 1899 a usually malignant tumor derived from mesothelial tissue (as that lining the peritoneum or pleura) … New Collegiate Dictionary
mesothelioma — Malignant tumour of the mesothelium, usually of lung; frequently caused by exposure to asbestos fibres, particularly those of crocidolite, the fibres of which are thin and straight and penetrate to the deep layers of the lung. Because of their… … Dictionary of molecular biology
mesothelioma — /mez euh thee lee oh meuh, mes , mee zeuh , seuh /, n., pl. mesotheliomas, mesotheliomata / meuh teuh/. Pathol. a malignant tumor of the covering of the lung or the lining of the pleural and abdominal cavities, often associated with exposure to… … Universalium
mesothelioma — noun An uncommon malignant tumour of the mesothelium, usually of the lungs after exposure to asbestos … Wiktionary
mesothelioma — [ˌmɛsə(ʊ)ˌθi:lɪ əʊmə, ˌmɛz , ˌmi:s , ˌmi:z ] noun Medicine cancer of mesothelial tissue, often associated with exposure to asbestos … English new terms dictionary
mesothelioma — meso·the·li·o·ma … English syllables