Which childhood brain tumor accounts for 15-25% of cases?

The correct answer is medulloblastoma, which accounts for approximately 15-25% of pediatric brain tumors. Medulloblastoma is the most common malignant brain tumor in children, arising from the cerebellum and often presenting with symptoms related to increased intracranial pressure or cerebellar dysfunction. This tumor type is characterized by its aggressive behavior, potential for metastasis, and distinctive histopathological features that can aid in its diagnosis.

Cerebellar astrocytomas, while relevant in pediatric neuro-oncology, are less common and primarily represent low-grade tumors, generally contributing to a smaller percentage of childhood brain tumors. Acute lymphoblastic leukemia, though serious, is not a type of brain tumor and is an entirely different category of childhood malignancy. Retinoblastoma, while significant as the most common ocular cancer in children and also classified in pediatric cancers, does not fall under brain tumors and comprises a smaller percentage than the primary brain tumors like medulloblastoma.

In summary, medulloblastoma stands out as the leading brain tumor in childhood cases, aligning with the statistic of 15-25%, highlighting its prevalence and clinical significance in the pediatric population.