Background: Acute lymphoblastic leukemia is the most common malignancy in childhood. The survival rate has increased steadily over the last 40 years.
Material and methods: All children aged 0-15 years and diagnosed in Norway in the period 1992-2000, were included in the study (n = 301). The patients were followed up until 1.1. 2005.
Results and interpretation: The diagnosis was made in 301 children, 33 new cases per year (range 24 to 40) on average. The peak incidence was between 2 and 5 years. Four of 6 infants with acute lymphoblastic leukemia and all 4 with mature B-cell leukemia are alive. Two of the remaining 291 children died before treatment was started. 289 were all treated according to the common Nordic NOPHO-ALL 1992 protocol. All children achieved remission (99.7%), except for one who died before remission was achieved. 55 children (19%) relapsed. Radiation to the brain as part of central nervous system prophylaxis was given to just 10% of the children. The 10-year event-free survival (p-EFS) was 76%, and 244 of 289 (84%) were alive 4-13 years after the diagnosis was made. The data are comparable with the best international results.