Mesothelioma: Introduction

Approved by the Cancer.Net Editorial Board, 07/2017

ON THIS PAGE: You will find some basic information about this disease and the parts of the body it may affect. This is the first page of Cancer.Net’s Guide to Mesothelioma. Use the menu to see other pages. Think of that menu as a roadmap for this complete guide.

About cancer

Cancer begins when healthy cells change and grow out of control, forming a mass called a tumor. A tumor can be cancerous or benign. A cancerous tumor is malignant, meaning it can grow and spread to other parts of the body. A benign tumor means the tumor can grow but will not spread.

About mesothelioma

Mesothelioma is a rare cancer that begins in the lining of different internal organs of the body.

  • Approximately 75% to 80% of mesotheliomas begin in the lining surrounding the lungs, called pleural mesothelioma. Pleural mesothelioma begins in the chest cavity, but it does not start in the lungs. As such, it is often incorrectly grouped with lung cancer.

  • Peritoneal mesothelioma makes up about 10% to 20% of mesotheliomas. This type of mesothelioma begins in the tissue surrounding the abdominal area, called the peritoneum.

  • The rarest types of mesothelioma include:

    • Mesothelioma that begins in the lining around the heart, called the pericardium

    • Mesothelioma that begins in the lining around a man’s testicles, called the tunica vaginalis

Types of mesothelioma

There are 3 main types of mesothelioma:

  • Epithelioid type. About 70% of people diagnosed with mesothelioma have the epithelioid type. Epithelioid mesothelioma may grow slower and chemotherapy often works better for this type.

  • Sarcomatoid type. Between 7% to 15% of people diagnosed with mesothelioma have the sarcomatoid type. Sarcomatoid mesothelioma may be more resistant to treatment compared with the other 2 types of mesothelioma. Standard chemotherapy often does not work well for this type of mesothelioma.

  • Mixed, or biphasic, type. Between 10% to 20% of people diagnosed with mesothelioma have the mixed type. The term “mixed” or “biphasic” means that the cancer contains both epithelioid and sarcomatoid types. Treatment does not work as well for this type when compared with the epithelioid type. However, treatment for this type often works better than for the sarcomatoid type.

The next section in this guide is Statistics. It helps explain the number of people who are diagnosed with this disease and general survival rates. You may use the menu to choose a different section to read in this guide.