Epidemiology of childhood cancer.

The present contribution reports childhood cancer incidence and survival rates as well as time trends and geographical variation. The report is based on the databases of population-based cancer registries which joined forces in cooperative projects such as Automated Childhood Cancer Information System (ACCIS) and EUROCARE. According to these data, which refer to the International Classification of Childhood Cancer, leukemias, at 34%, brain tumors, at 23%, and lymphomas, at 12%, represent the largest diagnostic groups among the under 15-year-olds. The most frequent single diagnoses are: acute lymphoblastic leukemia, astrocytoma, neuroblastoma, non-Hodgkin lymphoma, and nephroblastoma. There is considerable variation between countries. Incidence rates range from 130 (British Isles) to 160 cases (Scandinavian countries) per million children. Incidence rates have shown an increase over time since the mid of the last century. In Europe, the yearly increase averages 1.1% for the 1978-1997 period and ranges from 0.6% for the leukemias to 1.8% for soft-tissue sarcomas. The probability of survival has risen considerably over the past decades, with the EUROCARE data showing an improvement of the relative risk of death by 8% when comparing the 2000-2002 time span to the 1995-1999 period. Regarding the years 1995-2002, the data show an overall 5-year survival probability of 81% for Europe and similar values for the USA. The data presented here describe the cancer situation with a specific, European focus. They are drawn from population-based cancer registries that ensure excellent data quality, and as a consequence represent the most valid European population-based data existing at present. It is also apparent that not all countries have data available from nationwide childhood cancer registries, a situation which warrants further improvement.