Mesothelioma is a somewhat rare form of cancer, with 2,000 to 3,000 new cases diagnosed annually in America alone. Mesothelioma is a worldwide epidemic, other countries associated with asbestos exposure and mesothelioma are the United Kingdom, Australia, and Canada, as well as several developing countries which do not have any regulations or safety protocols in place. The United States and Canada are the last two fully developed countries yet to ban asbestos.
The National Institute of Health estimates that 11 million people were exposed to asbestos between 1940 and 1978. The American government stepped in and placed regulations on asbestos in the 1970s and 1980s, however the material was used in over 3,000 products, as well as in construction and industrial applications. Some of those products can still be found today and homes and other buildings constructed prior to the 1970s are likely to contain the material. A rising link to asbestos exposure among those who did not work on these job sites are both men and women completing do-it-yourself renovations on older homes and buildings.
Mesothelioma is more likely to occur in Caucasians and Hispanics than in African Americans and Asian Americans, and men are four times more likely to be diagnosed with mesothelioma than women are. The rate of mesothelioma diagnosed increased in the United States from the 1970s to the 1990s and has since slowly decreased, but only in men; in women the numbers continue to rise. However, these gender distinctions are specific to the United States; other countries differ in their rates of mesothelioma which generally correlates to their usage rates and dates of regulation. In many other countries the rate of mesothelioma is rising. The risk for mesothelioma increases with age, as the disease is rarely diagnosed in people under the age of 45; three out of four cases occur in those over the age of 65. Diagnosis of mesothelioma in children has been recorded, but is extremely rare. The American Cancer Society notes that the average person has a lifetime risk of mesothelioma of 1 in 770.
Mesothelioma Types and Histology
Of the three main types of mesothelioma pleural is the most common with a survival rate of eight percent living beyond three to five years after onset of initial symptoms. The average life expectancy for pleural mesothelioma is 12 months. Peritoneal mesothelioma carries a ten month survival rate, and pericardial is the least common of the three. A fourth extremely rare type of mesothelioma that affects the lining of the tunica vaginalis has been recorded in less than 100 people total since recognition of the disease location.
Another way of classifying mesothelioma is to view the disease’s cell arrangement under a microscope. These three classifications are referred to as epithelioid, sarcomatoid, and biphasic which is a mix of the former. 50 to 60 percent of diagnoses are epitheliod, 10 to 20 percent are sacromatoid, and 30 to 40 percent are biphasic, overall sarcomatoid and biphasic types are harder to treat.
Patients diagnosed with mesothelioma are usually given a life expectancy ranging from 4 to 18 months from the time of diagnosis. Approximately ten percent of patients diagnosed live longer than five years following their primary diagnosis.