Glioblastoma of the optic chiasm.

Primary malignant gliomas of the optic nerve and chiasm are rare, and are usually rapidly fatal in adults. We report a 48-year-old woman with a glioblastoma multiforme arising from the optic chiasm. Following radiotherapy, our patient survived nearly 14 months, which is the longest survival reported in patients with this diagnosis. There have only been four other reports of glioblastoma multiforme arising from the optic chiasm as distinct from secondary involvement of the chiasm, in the last 40 years.