Metastasis of an optic glioma through a ventriculoperitoneal shunt.

Metastatic spread of an optic glioma through a ventriculoperitoneal shunt resulted in the accumulation of malignant ascites in a young boy. Chemotherapy with vincristine, CCNU, and prednisone resulted in regression of the ascites and no further tumor progression. Extracranial metastasis of such a slow growing tumor is a rare occurrence; however, in this case, the spread through the shunt further emphasizes the need for protective filters in the shunts.