Expanding Horizons: A Novel Presentation of Posterior Fossa Pilocytic Astrocytoma With Intracranial and Spinal Leptomeningeal Spread

Pilocytic astrocytoma is a low-grade tumor with excellent prognosis after total resection. However, leptomeningeal spread leads to unfavorable prognosis. A novel case of pilocytic astrocytoma (PCA) with intracranial as well as spinal leptomeningeal dissemination (LD) of a 15-year-old boy who presented with headache, vomiting and fainting spells. A magnetic resonance imaging (MRI) brain showed a mass lesion with cystic component and enhancing mural nodule in posterior fossa near cisterna magna making communication with ventricular chain with unique diffuse cranial basal leptomeningeal enhancement. Biopsy was done and case was diagnosed by department of pathology to be a PCA. Patient then underwent MRI whole neuro-axis for LD, which showed leptomeningeal spread with enhancing mural nodule within a cystic lesion in sacral portion of spinal canal. Our case report highlights the importance of close surveillance of intra-cranial as well as leptomeningeal spread of pilocytic astrocytoma.