Remote acute demyelination after focal proton radiation therapy for optic nerve meningioma.
We present a unique patient with delayed onset, acute demyelination that occurred distant to the effective field of radiation after proton beam radiotherapy for an optic nerve sheath meningioma. The use of stereotactic radiotherapy as an effective treatment modality for some brain tumors is increasing, given technological advances which allow for improved targeting precision. Proton beam radiotherapy improves the precision further by reducing unnecessary radiation to surrounding tissues. A 42-year-old woman was diagnosed with an optic nerve sheath meningioma after initially presenting with vision loss. After biopsy of the lesion to establish diagnosis, the patient underwent stereotactic proton beam radiotherapy to a small area localized to the tumor. Subsequently, the patient developed a large enhancing mass-like lesion with edema in a region outside of the effective radiation field in the ipsilateral frontal lobe. Given imaging features suggestive of possible primary malignant brain tumor, biopsy of this new lesion was performed and revealed an acute demyelinating process. This patient illustrates the importance of considering delayed onset acute demyelination in the differential diagnosis of enhancing lesions in patients previously treated with radiation.
Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Boston, MA 02114, USA. Electronic address: nredjal@mgh.harvard.edu.
Navid
N
Redjal
Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Boston, MA 02114, USA.
Pankaj K
PK
Agarwalla
Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
Jorg
J
Dietrich
Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
Nikolaj
N
Dinevski
Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
Anat
A
Stemmer-Rachamimov
Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Boston, MA 02114, USA.
Brian V
BV
Nahed
Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
Jay S
JS
Loeffler
D000328:Adult; D003711:Demyelinating Diseases / Q000209:etiology* / Q000473:pathology; D005260:Female; D005625:Frontal Lobe / Q000473:pathology*; D006801:Humans; D008577:Meningeal Neoplasms / Q000532:radiotherapy*; D008579:Meningioma / Q000532:radiotherapy*; D019574:Optic Nerve Neoplasms / Q000532:radiotherapy*; D061766:Proton Therapy / Q000009:adverse effects*
Demyelination; Edema; Meningioma; Optic nerve; Proton beam; Stereotactic radiotherapy