Some cases of ovarian cancer in women with a history of asbestos exposure may actually be misdiagnosed peritoneal mesothelioma. That is the conclusion of scientists from the University of Western Australia who are trying to evaluate a possible link between asbestos and ovarian cancer.
Doctors have known of the link between mesothelioma and asbestos for decades. Over the years, other cancers, including gastrointestinal, kidney, throat and gallbladder, have also been associated with exposure to this toxic mineral. But, because fewer women traditionally work in industrial jobs and, thus, have less occupational asbestos exposure, the link with ovarian cancer has been harder to prove.
Adding to the challenge is the possibility that some cases of peritoneal mesothelioma may have been misdiagnosed as ovarian cancer. Peritoneal mesothelioma is a form of mesothelioma that affects the lining of the abdomen. Like all cancers, it can metastasize or spread to other parts of the body. In women, one of the areas where mesothelioma can spread are the ovaries.
To explore the potential ovarian cancer/asbestos link, researchers at the Western Australia Institute for Medical Research conducted a meta-analysis of sixteen studies performed between 1950 and 2008. Several of the studies did appear to indicate a “statistically significant excess mortality” from ovarian cancer, based on the cause of death listed on patient death certificates. But there was a problem. In two of the studies, when the pathology specimens were reexamined later, several cases of what was thought to have been ovarian cancer were proven, instead, to be peritoneal mesothelioma.
While there may be a link between asbestos and ovarian cancer, the Australian scientists point out that potential mesothelioma misdiagnoses makes this link harder to quantify. In fact, women in the Australian meta-analysis who were thought to have had ovarian cancer were more likely than women in the reference population to have been exposed to asbestos, confirming the findings of a number of other studies. However, the researchers conclude that, based on the inconsistent results in their meta-analysis, it is still impossible to accurately estimate the ovarian cancer risk in asbestos-exposed women.
Reid, A. “Does exposure to asbestos cause ovarian cancer? A systematic literature review and meta-analysis”, May 24, 2011, Cancer Epidemiology, Biomarkers, and Prevention, Epub ahead of print.
Solomon, Gina. “Ovarian Cancer”, February 17, 2004, The Collaborative on Health and the Environment.