Leptomeningeal dissemination of pilocytic astrocytoma

Summary A unique case of pilocytic astrocytoma (PCA) with leptomeningeal dissemination occurring after surgery in a 2-year-old boy who presented with progressive left-sided weakness is reported. A cranial magnetic resonance imaging (MRI) disclosed a lesion with a cystic component in the right thalamus and basal ganglia. The lesion was subtotally resected and diagnosed by the pathology department to be a PCA. An MRI 16 days after surgery revealed a residual tumor with a tumor seeding along the surgical tract and in the meninges. The patient then underwent chemotherapy and a cranial MRI. Eleven months later the patient did not disclose any residual or additional lesions. The patient continues to do well at the time of this writing. This case illustrates a unique instance of leptomeningeal dissemination through the surgical tract of a resected cerebral PCA in a child.