Neuropsychological Comparison of Pediatric Medulloblastoma and Pilocytic Astrocytoma: Existing Knowledge and Future Directions

Alice Ann Holland

Alice Ann Holland Children's Medical Center Dallas, Texas

Abstract

This paper reviews existing knowledge regarding neuropsychological late effects of pediatric medulloblastoma and cerebellar pilocytic astrocytoma, with the goal of highlighting areas for future research. Comparison of these two tumors, which occupy the same region of the brain, is arguably the ideal method for researching the late effects of craniospinal radiation, as medulloblastoma patients receive radiation, while cerebellar pilocytic astrocytoma patients do not. Such comparative research, which has yet to be extensively conducted, has the potential to enhance targeted neuropsychological interventions and help neuro-oncologists make treatment decisions regarding use, frequency, duration, and dose of radiation. A discussion of cognitive fluency is included, detailing the importance of researching this overlooked construct in these two tumor groups. Existing knowledge of differential processing speed deficits in these populations, which appears to be strongly related to administration of craniospinal radiation, provides a rationale for such investigation.

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