What is Malignant Mesothelioma?
Malignant mesothelioma is a cancerous tumor of the lining of the
lung and chest cavity (pleura) or lining of the abdomen (peritoneum)
that is almost always caused by sustained exposure to asbestos.
Malignant mesothelioma is a diffuse tumor that affects men more
frequently than women. Sustained exposure to asbestos is the
predominant risk factor. However, smoking dramatically increases
risk amongst the asbestos-exposed. The latent period between
asbestos exposure and onset of symptoms can be 20 to 50 years or
The median age of diagnosis is 60. The tumor can spread rapidly to
involve the pericardium (sac around the heart), mediastinum, and
opposite pleura. Progressive pain and shortness of breath can occur.
The tumor is usually associated with a pleural effusion.
Differentiation of the tumor from other conditions of the pleura and
other types of cancer can be difficult, even when experienced
pathologists are viewing biopsy samples.