Types of Mesothelioma

There are four types of mesothelioma: Pleural (lungs), peritoneal (abdomen), pericardial (heart) and testicular. Pleural and peritoneal are the most common types, comprising nearly 90 percent of all diagnoses. Learn more about your specific type and what it means for your treatment options.

Medical experts acknowledge four main types of mesothelioma — each named for the area of the body where the cancer forms. The most common type, pleural mesothelioma, develops in the lining of the lungs.
Peritoneal mesothelioma forms in the peritoneum, the membrane that lines the abdominal cavity. This is the second-most prevalent type. The overwhelming majority of mesothelioma specialists treat patients with one of these two types.

The rarest forms of the disease are pericardial and testicular mesothelioma. Pericardial mesothelioma starts in the lining of the heart, while testicular mesothelioma develops in the lining of the testicles. Together, these types account for less than 2 percent of all mesothelioma diagnoses.

Primary Cause of All Mesothelioma Types

All the different types and subtypes of this disease share one common thread. They are caused primarily by a prolonged exposure to asbestos, usually in the workplace. If a doctor suspects that you have any form of mesothelioma, you should think back through your work background to find a connection to when you worked with or around asbestos materials and products.
Most pleural mesothelioma patients can remember a time when they breathed in asbestos fibers. In cases of peritoneal mesothelioma, patients often swallowed the fibers. Researchers are less certain about how asbestos triggers the pericardial and testicular forms of the disease.