Archive for the ‘mesothelioma prognosis’ Category

Asbestos and Malignant Mesthelioma

Saturday, May 6th, 2006

Many people are wondering about the risks of asbestos exposure and getting malignant mesothelioma. Mesothelioma is a type of cancer on the pleura, or lining of the lungs. It can lead fluid in the lungs, difficulty breathing, and eventually death. When it comes to how our bodies age and handle illness, 65% depends on the environment, like the things we feed, expose, and do to our bodies. The remaining 35% is due to genetics, that wonderful nuclear and mitochondrial DNA that we got from ours parents and mothers, respectively.

When we think about environment, consider the following study. A 35-year period evaluation of workers in an asbestos factory in Poland revealed that increased rates of lung cancers, pleural mesothelioma, and all malignant cancers were higher in these workers than in the general population. Of the 4,187 subjects studied (2805 men and 1382 women), five died from pleural mesothelioma. Also, the risk for these types of illness did not differ between those that had a preceeding documented diagnosis of lung asbestosis and those that did not. So, where people work, and the polutants they are exposed to, clearly influence disease risks.

Now with genomics laboratories, investigation of disease risk is taken to a new level. A recent study in Northwest Italy evaluated single nucleotide DNA polymorphisms in 4 genes responsible for DNA repair. Polymorphisms are like typos in the DNA language. The assumption was that sloppy DNA repair increased the risk for this cancer when a gene-damaging substance like asbestos was thrown into the picture. It’s like trying to fix an important system with an entire chapter ripped out of the repair manual. So seven different variations of these 4 genes were studied in 81 malignant mesothelioma patients and 110 of their age-matched and sex-matched controls. All subjects were residents of Casale Monferrato, a town polluted with asbestos. The results showed that with one type of polymorphism (or DNA typo) a 2.147 oddds ratio existed for this disease, another variant (or DNA typo) had a 4.09 odds risk ratio. These genetic variations can certainly put people at an increased risk of developing the cancer. This is valuable information because the residents of this town can now look at their family genetics and give more consideration about whether or not they should move out of there!

Environment and genetics…we are getting more options now than ever before to learn about our risks of getting cancers, like malignant mesothelioma. If you have any concerns about a history of personal asbestos exposure, I encourage you to explore with your physician or health care provider what diagnostic tools are available for further evaluation.

References:
Dianzani I, et al. Polymorphisms in DNA repair genes as risk factors for asbestos-related malignat mesothelioma in a general population study. Mutant Res. 2006 Marc 23; (epub ahead of print)
Wilezynska U, Szymezak W, Szeszenia-Dabrowska N. Mortality from malignant neoplasms among workers of an asbestos processing plant in Poland: results of prolonged observation. Int J Occup Med Environ Health 2005; 18(4):313-26.