Mesothelioma

mesothelioma?

Mesothelioma is a rare form of cancer (malignancy) that most frequently arises from the cells lining the sacs of the chest (the pleura) or the abdomen (the peritoneum). Pleural mesothelioma is the most common form, often presenting with symptoms in the chest area. Peritoneal mesothelioma is much less common. This can effect the organs in the abdomen, and its symptoms are related to this area of the body, that is, abdominal swelling, nausea, vomiting, and bowel obstruction. The rarest form of mesothelioma is pericardial mesothelioma, which involves the sac surrounding the heart.
There are two major cell types of mesothelioma, epithelial and sarcomatoid. Sometimes both of these cell types can be present. The sarcomatoid type is rarer and occurs in only about 15% of cases; it portends a poorer prognosis. In very rare cases, mesothelioma can originate from benign, non-malignant cells. This so-called benign mesothelioma can be cured surgically.

What are the symptoms of mesothelioma?

Most people present with complaints of shortness of breath. They also can have complaints of chest pain. Surprisingly, this pain is often not pleuritic; that is, it does not get worse with deep breathing. This is surprising in that the pleura (outer surface of the lung) is often involved in this disease, and most other diseases involving the pleura are often associated with pleuritic pain (pain that worsens with deep breathing). Patients may also be asymptomatic, with the disease discovered by physical exam or an abnormal chest X-ray.
As the disease progresses, shortness of breath increases, and weight loss, decreased appetite, and night sweats can develop. Local invasion by the tumor can result in changing of voice, loss of function of the diaphragm, and symptoms specific to the area and involvement of adjacent structures.

What causes mesothelioma?

Most people with malignant mesothelioma have worked on jobs where they breathed asbestos. Usually, this involves men over 40 years of age. Others have been exposed to asbestos in a household environment, often without knowing it. Interestingly, the number of new cases of mesothelioma has been relatively stable since 1983, the same time that the restrictions on asbestos were instituted by the U.S. Occupational Safety and Health Administration (OSHA). In Europe, the number of new cases of mesothelioma continues to rise.