Childhood medulloblastoma in northwest England 1954 to 1997: incidence and survival.

The incidence, survival patterns, and presenting symptoms of children with medulloblastoma were studied. Data were ascertained from the Manchester Tumour Registry which is population-based and has collected data on all childhood malignancies in northwest England since 1954. Incidence rates standardized to the European standard population were calculated and Poisson regression models were used to examine temporal changes in the incidence rates during the period 1954 to 1997. Kaplan-Meier survival curves were derived and used to study changes in survival patterns. World-standardized incidence rates were 5.5 per million child years in males and 3.4 per million child years in females. Incidence rates increased from the 1950s to the 1980s but have declined recently. The 5-year survival rate has improved from 29 to 58% with similar rates for males and females. The 1-year survival rate has also improved, but females had worse survival at this point (58%) than males (75%). The type of symptom or sign at presentation is strongly affected by age, with 10 of the 22 recorded symptoms or signs showing significant age differences. The older the child is, the more likely is the presentation to show pressure features of headache, vomiting, and ophthalmic signs. Younger children present with non-specific features such as lethargy, behavioural disturbance, or increasing head size. Ataxia is seen in about 75% of children across the age range.