Cognitive deficits and predictors three years after diagnosis of a pilocytic astrocytoma in childhood

Purpose: To study prospectively cognitive deficits and predictors three years after diagnosis in a large pediatric series treated for pilocytic astrocytoma (PA).

Methods: Sixty-one out of 67 children were grouped according to infratentorial, supratentorial midline, and supratentorial hemispheric site. Intelligence, memory, attention, language, visual-spatial and executive functions were assessed. Included predictors were sex, age, relapse, interval diagnosis-assessment, hydrocephalus, kind of treatment, and tumor variables.

Results: All children with PA have problems with sustained attention and speed. In the infratentorial group there are deficits in verbal intelligence, visual-spatial memory, executive functioning, and naming too. Verbal intelligence and verbal memory problems occur in the brain stem tumor group. The supratentorial hemispheric tumor group has additional problems with selective attention and executive functioning and the supratentorial midline tumor group display no extra impairments. More specified the dorsal supratentorial midline tumor group displays problems with language and verbal memory. Predictors for a lower cognitive functioning are hydrocephalus, radiotherapy, residual tumor size, or age and for a better functioning are chemotherapy or treatment of hydrocephalus. Almost 60% of children had problems with academic achievement and risk factors were relapse and younger age at diagnosis.

Conclusion: Despite normal intelligence at long-term follow-up children treated for PA display invalidating cognitive impairments. Adequate treatment of hydrocephalus is important for a more favorable long-term cognitive outcome. Even children without initial severe deficits may develop cognitive impairments years after diagnosis, partly because of the phenomenon "growing into deficit" with devastating implications for their academic achievement and quality of life (QOL).