The Childhood Cancer Research Group

BackgroundGeneral BackgroundThe Childhood Cancer Research Group (CCRG) is based in the University of Oxford. Currently housed at 57 Woodstock Road, Oxford OX2 6HJ, it is administratively part of the University Department of Paediatrics (itself located across several sites, several miles away). For the foreseeable future, the core funding of the CCRG is envisaged to come from the Department of Health for England (& Wales) through the Policy Research Programme, with a further contribution made on behalf of the Scottish Ministers. Additional funding from other sources is therefore to be sought in a complementary rather than substitutive fashion.The CCRG houses the National Registry of Childhood Tumours (NRCT) - a population based register of malignancies and benign brain tumours diagnosed in children (less than 15 years of age), and domiciled in England, Wales or Scotland at the time of diagnosis - which covers the 1950s incompletely and the period 1962 to the present day as completely as possible. Incomplete data for Northern Ireland and Eire and for young people throughout the UK diagnosed at older ages are also held, together with those for other children who do not satisfy the definition of domicile.The CCRG is built around the NRCT. The CCRG's principal tasks are: (1) to use the NRCT data to fulfil the basic public health functions of a cancer registry through description and analyses of trends and distributions of cancer incidence, mortality and survival and to distribute NRCT data to potential users who make legitimate requests, within the constraints to release to which the CCRG is subject (2) to undertake a variety of more complex national and international research studies. Many of these are undertaken collaboratively with others outside the CCRG, and they include the Descriptive, Analytical and Genetic Epidemiology of childhood cancer, studies of Medical care and Outcomes in those in whom it is diagnosed, and the Preventive/Policy measures by which childhood cancer occurrence might be reduced.Hypotheses about childhood cancer causesVery little is known about the causes of most childhood cancers. There is increasing understanding of the molecular genetic changes in germ line and somatic cells which lie at the heart of the process but little knowledge of the causes which provoke them. Opinion would vary about the likely significance of a wide range of factors. We believe that universal agreement would be achieved only about the following as classes of causes of childhood cancer (though again, opinion would vary about their relative importance). Prenatal (genetic), intrauterine and post natal exposures are all important.Definitive causes of some cancers occurring in adulthood and/or childhood:Factors Evidence Genetic factors Retinoblastoma tumour suppressor gene mutations; other(heritable and heritable syndromes involving risk of childhood cancer e.g. Li non-heritable) Fraumeni syndrome or non-heritable congenital syndromes e.g. Down syndromeViral infections Hepatitis B and C for hepatic carcinoma; HTLV for leukaemia; EB virus for some lymphomas and nasopharyngeal carcinoma; HIV and HHV8 for Kaposi's sarcomaKinlen, Greaves and Smith hypotheses exist re: infection and childhood leukaemia arising as a rare consequence of exposure, but the infections are unknownTherapeutic levels Second tumours in children treated for primariesof ionising radiation Exposure to hormones Diethylstilboestrol (DES) exposure known to cause vaginal and chemicals in utero clear cell carcinoma, sometimes diagnosed in childhood, by transplacental though highly unusualtransmissionParticularly debated causes of some cancers occurring in childhood:Diagnostic ionising radiation (in utero and in childhood)Environmental ionising radiation (man made and natural; radon and gamma)Non-ionising radiation (EMFs; ultraviolet and childhood melanoma)Relationship of leukaemia, and other cancer risk to birthweightExposure to tobacco smoke carcino