Your organs, including the heart and lungs, are wrapped in a type of tissue called the mesothelium. It keeps them from rubbing against each other. There are several different types. The mesothelium lining that covers your lungs is called the pleura. The pericardium covers your heart. The peritoneum covers your abdominal organs. In men, the tunica vaginalis covers testicles. Mesothelioma is the name for cancer that begins in any of these mesothelium cells. Though any of these four areas can be affected, about three-quarters of cases of mesothelioma originate in the pleura.
Mesothelioma is linked to asbestos exposure. Asbestos—a naturally occurring, heat-resistant fiber—was commonly used in insulation, roofing and other building materials through the 1970s, but its usage has drastically declined in the last several decades because it is now known to be dangerous to your health. Though the number of cases of mesothelioma have gone steadily down over the past 40 years, roughly 3,000 cases are still diagnosed in the U.S. every year. Mesothelioma affects more men than women. And it can occur 30 or even 40 years after exposure to asbestos.
Mesothelioma is a difficult cancer to treat because it tends to spread to nerves and blood vessels. Current treatments can help relieve symptoms and possibly prolong life. Mesothelioma may be treated with surgery, radiation therapy and chemotherapy. Sometimes targeted therapy and immunotherapy are used as well.
“Mesothelioma is a rare cancer,” says Yale Medicine’s Anne Chiang, MD, PhD, a medical oncologist who treats lung cancers, “but there is still active clinical research, for example, with immunotherapy that is ongoing to try to improve the lives of patients with this disease.”