Geographic and ethnic variations in the incidence of childhood cancer. Br Med Bull 1996;52: 682–703

The total incidence of childhood cancer varies rather little between different regions of the world, with cumulative risk to age 15 nearly always in the range 1.0—2.5 per thousand. Acute h/mphoblastic leukaemia, especially in early childhood, is most common in populations of high socio-economic status and is the most frequent childhood cancer in all industrialised countries. The risk of Burkitt's lymphoma is highest in tropical Africa and Papua New Guinea; it is strongly associated with Epstein—Barr virus infection and intense immune stimulation by malaria. Other rymphomas are also relatively common in developing countries. Non-heritable retinoblastoma has a higher incidence among less affluent populations, suggesting an association with poor living conditions and maybe an infectious aetiology. In contrast, the incidence of Wilms ' tumour and Ewing's sarcoma varies largely on ethnic lines, indicating a strong role for genetic predisposition. Much of the variation in recorded incidence of brain tumours and neuroblastoma may be due to varying levels of case ascertainment. Recently the incidence of childhood Kaposi's sarcoma has risen substantially in parts of Africa severely affected by the AIDS epidemic. Geographic and ethnic variations in the incidence of childhood cancer Compared with the very large variations in cancer incidence among adults between different regions of the world, the total incidence of childhood cancer is relatively constant. The cumulative incidence to age 15 is nearly always in the range 1.0-2.5 per thousand and age-_ ,. standardised annual incidence rates (ASR) calculated using the world Corresponcfortco to: ° CAStiller, standard population lie between 75-140 per million1. There are, childhood Cancor however, more marked variations in the incidence of particular types RojBorch Group, o £ childhood cancer. These variations certainly affect the patterns of v'wboditock Rood disease encountered by clinicians serving different populations and may Oxford OX26HJ, UK also provide valuable clues to aetiological factors