Malignant mesothelioma is a deadly disease with a median survival of 6–15 months in affected patients. It is diagnosed in 2000–3000 Americans per year. There is not yet a well-validated effective treatment for any stage of the disease. It is derived from cells lining serosal surfaces including the pleura, pericardium, peritoneum, and rarely the tunica vaginalis, which is embryonically derived from the peritoneum. About 80% of mesotheliomas arise from the pleura, the focus of this chapter.

There are three main pathologic types of malignant mesotheliomas: epithelioid, mixed/biphasic, and sarcomatoid. Patients with the epithelioid type, the most common (50–70%) have the best prognosis.

Mesotheliomas typically occur in people over 40 years of age; the median age at diagnosis is 60. The male:female ratio is 5:1 which reflects the occupational exposure to asbestos, the most important risk factor. Indeed, asbestos exposure is found in 50–80% of patients though the percentage may be higher since even brief exposure may result in mesothelioma and the latency period averages 20–50 years. Considering this long latency and the fact that stiffer regulations to limit asbestos exposure to prevent mesothelioma were instituted only in the early 1970s, the incidence is expected to peak in 2010. Tobacco use is not a risk factor.

Most patients with mesothelioma present with shortness of breath (80%) and/or nonpleuritic chest pain or discomfort (50–60%), often many months in duration. Other symptoms include malaise, coughing, and sweats. Presenting signs include weight loss and fever.