1. www.swpho.nhs.uk The incidence of mesothelioma in the South West Region, Hampshire and the Isle of Wight C Devrell 1, S McPhail, A Evans, A Pring and J Verne South West Cancer Intelligence Service Increasing number of cases The number of cases of mesothelioma has been steadily increasing over the past twenty years. Between 2000 and 2003 there were about 300 cases per year, which is the level that had been predicted by the SWCIS model. The number is expected to peak at 325 cases per year between 2010 and 2015, and then fall. Areas with highest incidence Ports and dockyards in the South West have a high incidence of mesothelioma, especially Plymouth, Portsmouth and Southampton. The link between mesothelioma and heavy asbestos exposures in the shipbuilding industry is well known. Asbestos was used as insulation in ships, and workers were exposed during fitting out and ship-breaking activities 3. Swindon, where workers were exposed to asbestos in railway carriage building, is also in the top ten. Male to female ratio Mesothelioma is much more common in men than in women. This is consistent with exposure to asbestos dust occurring in predominantly male occupations. Overall, the male to female ratio is approximately 7:1. However, there are marked geographical variations. In Plymouth the ratio is 25:1, while in Bristol it is 3:1. SWCIS consulted the Trades Union Congress about these variations. They reported that dockyards in Plymouth had a history of providing their own laundry services, so families were not exposed to workers’ clothes. Conclusions The number of mesothelioma cases has steadily increased over the past 20 years and is expected to peak at 325 cases per year in the next decade. It should then fall. The areas with highest incidence have a history of heavy occupational exposure to asbestos through shipbuilding and railway carriage building. Monitoring by the Health & Safety Executive and cancer registries will need to continue in order to confirm that current regulations are protecting workers. Background Mesothelioma is a rare type of cancer that arises in the outer lining of the lungs (pleura). Very occasionally it arises in other mesothelial tissue such as the lining of the abdomen or heart. Approximately 8 out of 10 cases are caused by exposure to asbestos dust, but the disease has a long latency period, which means it often takes up to 40 years, or even longer, to develop. The disease is usually fatal within a couple of years of diagnosis. Although exposure to asbestos has been strictly regulated since the late 1970s, mesothelioma is still arising in people, mainly men, who were heavily exposed before the regulations came into effect. 1 claire.devrell@swpho.nhs.uk Cancer Analysis Team, Tel 0117 970 6474claire.devrell@swpho.nhs.uk 2Harling C, Verne J (2002) – Forecasting the Incidence of Mesothelioma in the South West. Poster available on the SWPHO website 3Health & Safety Executive, Mesothelioma in Great Britain: An Analysis by Geographical Area 1981-2000 Aims To examine trends in incidence and mortality for mesothelioma in the South West. To confirm the accuracy of the 2002 SWCIS prediction of the number of mesothelioma cases expected locally over the next 50 years 2. Comparisons with national data In 2004 there were more deaths in England and Wales from mesothelioma (1,633 deaths) than melanoma (1,597 deaths) or cancer of the cervix (957 deaths). (Office for National Statistics) Plymouth and Portsmouth were the two Unitary Authorities with the largest number of male deaths from mesothelioma in England between 1981 and 2000 3. Plymouth and Portsmouth remain in the top twenty Authorities in England with the highest number of deaths during the five years 1999-2003. (HSE data) Who is now most at risk? The Health & Safety Executive has reported that the group of workers currently most at risk of exposure are maintenance workers such as electricians, plumbers and shop fitters, and in 2002-04 the construction industry (including insulation and asbestos removal workers) had the highest rates of Industrial Injuries Scheme Assessments for mesothelioma. (HSE website) Fig 2 Trend in number of cases of mesothelioma in the SWCIS region, 1982-2002 (three year rolling average, male and female) Fig 3 Top ten Unitary and Local Authorities in the SWCIS region for number of cases of mesothelioma, 1998-2003 Age at diagnosis Most cases of mesothelioma occur in men aged 60 or more, and there are very few cases in people aged under 50. This is consistent with people having been exposed in the 1950s and 60s when asbestos use was at its peak. Fig 1 Number of cases of mesothelioma in the SWCIS region by age group, 1989-2003