Some mesothelioma researchers are proposing a genetic component to this aggressive cancer long associated with asbestos. At the Mesothelioma Applied Research Foundation’s 2010 International Symposium, Jill Ohar MD of Wake Forest School of Medicine reported on research that supported the possibility that people who develop mesothelioma may have a genetic susceptibility.
Between 1940 and 1980, asbestos was an extremely common material in American industry, used in shipbuilding, aircraft fabrication, plumbing, insulation, railroad and automotive brakes and clutches, ceiling tile, floor tile, drywall, fireproofing materials, cement, and literally hundreds of other uses. An estimated 40 per cent of the US workforce, about 27 million Americans , was exposed in their workplaces to asbestos. The large majority of those exposed have not developed mesothelioma. The number of new mesothelioma cases identified each year has stayed constant at about 3000 per year.
The relatively small number who develop mesothelioma has led researchers to ask what might be the differences, among workers who experienced the same exposure to asbestos, between the majority who did not develop mesothelioma, and those who did.
Ohar and her colleagues worked from their database of 5000 people who had been exposed to asbestos, of whom 327 developed mesothelioma. They asked all of them about their asbestos exposure and their general health status. Their answers showed some very interesting patterns.
- Age of first exposure: those workers who developed mesothelioma tended to be younger at their first exposure to asbestos. In the 1940’s, they were the young men and women who volunteered out of high school, at age 17 or 18 to join the military, or work in defense industries. Cells in younger people tend to be more vulnerable to carcinogenic (cancer-causing) agents. Even a few years’ delay, time spent in college or in work that did not involve exposure to asbestos, seems to have had a protective effect.
- Military service: Mesothelioma patients were more likely to have served in the military. Service in the military increased the odds of exposure to asbestos.
- Other cancer diagnoses: Mesothelioma patients were three times more likely than other workers exposed to asbestos to have had another cancer diagnosis at the time of diagnosis of their mesothelioma. This suggests a greater vulnerability, probably genetically mediated, to carcinogenic agents.
- Cancer in first-order relatives: People diagnosed with mesothelioma were also three times more likely than other workers exposed to asbestos to have a first-order relative (a parent, a brother or a sister, or a child) who had a cancer diagnosis. Children of people with a mesothelioma diagnosis were seven times more likely to have a cancer diagnosis.
The message in Dr Ohar’s research is that mesothelioma may be part of a broader genetic susceptibility to cancer-causing agents. Genetic susceptibility by itself does not lead to a diagnosis of meso. Exposure to asbestos does not guarantee that a person will get meso. But combine exposure, especially at a young age, with genetic susceptibility, and the odds for developing mesothelioma rise dangerously.
If you or a loved one has been exposed to asbestos fibers, especially in the workplace, and has received a diagnosis of mesothelioma, you need to consult with an experienced asbestos mesothelioma lawyer to determine whether you may have an actionable case against the employer.