What are the facts about mesothelioma?

It takes a long time to develop
Mesothelioma is characterized by having a long latency period, which means that symptoms don’t develop for 20–50 years after environmental exposure. The average age at which symptoms usually begin to appear is around 60 years old.

It is a relatively rare disease
An estimated 2,000 to 3,000 cases of mesothelioma are diagnosed each year in the US. In other countries, the number of cases differs. Overall, the number of cases reported each year appears to be increasing.

It occurs in men more than in women
Mesothelioma affects men about three times more often than women in the US. Incidence rises steadily with age. In other parts of the world, where exposure comes primarily from other environmental sources, such as in Turkey, mesothelioma occurs about equally in men and women.

It develops mostly on the lungs
The most common place for mesothelioma to develop is on the lungs. About two-thirds of all mesothelioma cases develop in the pleural mesothelium. This mesothelioma on the lungs is called malignant pleural mesothelioma (MPM). The remaining cases develop in the peritoneal mesothelium in the abdomen. A tumor in the abdominal mesothelium is called peritoneal mesothelioma. Rarely, mesothelioma occurs in other mesothelial tissue, such as on the heart or on the reproductive organs.