Mesothelioma is a rare form of cancer that arises from the pleura or, less often, from the peritoneum. The disease is almost always fatal and the median time between diagnosis and death is less than one year [1,2]. Mesothelioma is strongly associated with occupational exposure to asbestos fibres. Industries with high exposure to asbestos in the past included mining, shipyard working and asbestos cement manufacture. The annual numbers of mesothelioma deaths in Great Britain increased 12-fold in the period from 1968 to 2001[3] and an epidemiological model that incorporated the historical use of asbestos suggested that the annual numbers of deaths will continue to rise to a peak at around 1950–2400 deaths per year in 2011–2015. The aim of this analysis was to examine the certified causes of death of patients diagnosed with mesothelioma, and assess the validity of mortality data as a proxy for data on mesothelioma incidence.

Initially, we extracted the numbers of mesothelioma cancer registrations and mesothelioma deaths nationally for 2004 from the Cancer Information System (CIS), which provides cancer registration and cancer mortality data from the whole of England. Thereafter, we extracted cancer registrations of patients diagnosed with mesothelioma in the South East of England area between 2000 and 2004 from the Thames Cancer Registry database. Patients who had cause of death specified on the death certificate were identified and used for the analysis. The deaths were classified hierarchically as follows: Firstly, we identified death certificates that mentioned mesothelioma as one of the causes of death. Secondly, among the remaining death certificates, we identified those that mentioned lung cancer as a cause of death. Third, among the now remaining death certificates, we identified those that mentioned an unspecified cancer as a cause of death. Last, there remained a group of death certificates that included no mention of mesothelioma, lung cancer or unspecified cancer….. (more…)