Radiation-induced tumor after stereotactic radiosurgery for an arteriovenous malformation: case report.
OBJECTIVE
To present a rare case of a radiation-induced malignancy after stereotactic radiosurgery.


METHODS
A 34-year-old woman presented with headaches. Imaging studies demonstrated a 4.5-cm arteriovenous malformation located in the pineal region. She was treated with a two-isocenter plan to a total dose of 1500 cGy prescribed to the 70% isodose line. She was lost to follow-up and presented with a change in mental status, nausea, headaches, and a generalized seizure 9 years later. Magnetic resonance imaging scans demonstrated a large, heterogeneously enhancing mass partially in the treatment volume.


METHODS
Surgical debulking demonstrated an infiltrating glial neoplasm consistent with a glioblastoma multiforme. There was no staining for epidermal growth factor receptor, whereas greater than 75% of nuclei stained positively with p53.


CONCLUSIONS
The risk of radiation-induced tumors is currently unknown but needs to be determined to assess the risk-benefit profile for each patient.
Berman
Edwina L
EL
Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111, USA.
Eade
Thomas N
TN
Brown
Daniel
D
Weaver
Michael
M
Glass
Jon
J
Zorman
Greg
G
Feigenberg
Steven J
SJ
D000328:Adult; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000209:etiology* / Q000601:surgery; D005260:Female; D005910:Glioma / Q000175:diagnosis* / Q000209:etiology* / Q000601:surgery; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000601:surgery*; D009381:Neoplasms, Radiation-Induced / Q000175:diagnosis* / Q000209:etiology* / Q000601:surgery; D016634:Radiosurgery / Q000009:adverse effects*