Diffuse leptomeningeal involvement by a ganglioglioma in a child. Case report.

Gangliogliomas are tumors composed of neuronal and glial elements that typically grow slowly by expansion only. This report describes a 20-month-old girl with a ganglioglioma that extensively involved the subarachnoid space; microscopic foci of tumor were found in the brain and spinal cord. Despite chemotherapy and radiation therapy, the child died 5 months after diagnosis. Molecular genetic analysis showed loss of chromosome 17p DNA sequences in the tumor tissue.