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Epidemiology of adult brain tumours in Great Britain and Ireland

The objective of this study was to review published reports on the epidemiology of primary brain tumours in adults and present the body of knowledge related to these tumours in Great Britain and Ireland. A literature search of all published epidemiological data on brain tumours was conducted in Pre-Medline, Medline, Embase and the Cochrane databases from 1966 to the present. A hand search of all the references alluded to was conducted and older studies identified. The articles were reviewed and tabulated. The papers were subjected to descriptive analysis. Information available to the public and held with the Cancer Registries was reviewed, and cross-referenced with published evidence. To our knowledge, only seven papers have discussed the epidemiology of primary brain tumours in adults. The different methodology of the populationbased studies of brain tumours and the different time periods they investigated makes them incomparable. Two papers with comprehensive and detailed strategies for case ascertainment have both recorded tumour incidences of 21 per 100,000 person years. The results of the better studies are at variance with reports from the Cancer Registries. On the basis of the current studies, Cancer Registries appear to under-estimate the incidence of such tumours in adults. It is apparent that a significant number of tumours especially benign varieties are not recorded by some Cancer Registries. The previous estimates, patterns of incidence, prevalence, and survival of brain tumours in Great Britain and Ireland, may thus be incorrect. Patterns of primary brain tumours in adults have not been widely reported in GB and Ireland and the aetiology remains largely unknown. The need for current estimation of geographical and secular variations was identified. This demands closer co-operation between medical and allied staff, and the Cancer Registries. Prospective regional studies of incidence patterns and up to date epidemiological appraisal is deemed necessary. Meanwhile, Cancer Registries should seriously consider the inclusion of all primary brain tumours in their database.