Malignant transformation of benign cerebellar astrocytoma

A patient who had a well‐differentiated cerebellar astrocytoma resected at 4 years of age, had glioblastoma multiforme of the cerebellum after a symptom‐free interval of 28 years. Late malignant transformation of a cerebellar astrocytoma of childhood is rare and previous cases are reviewed. Cerebellar astrocytomas are typically among the most benign of primary brain malignancies with excellent long‐term survival rates, sometimes with incomplete resection. This patient indicates that follow‐up needs to be long‐term because biologic behavior cannot be predicted fully in all cases.