There are three main types of mesothelioma:

• Epithelioid
• Sarcomatoid
• Mixed/biphasic

These occur in different parts of the body and can be either:

• Pleural mesothelioma
• Peritoneal mesothelioma

The epithelioid mesothelioma type occurs in 50%-70% of all cases—the highest rate of occurrence. Mixed/biphasic mesothelioma types occur in 20%-30% of all cases—the second highest rate of occurrence. These types are a mix of epithelioid and sarcomatoid. Sarcomatoid occurs in 7%-20% of all cases—the lowest rate of occurrence, but it is believed to be the most aggressive mesothelioma type.

Each type of mesothelioma occur in a different area of the body. Most mesothelioma cancer occurs in the chest cavity and is called pleural mesothelioma. Ten to twenty percent (10%-20%) of mesothelioma occurs in the abdomen and the cancer is called peritoneal mesothelioma.

While treatments are generally the same for all three mesothelioma types, they may vary depending on the location of the cancer.