Gamma Knife Radiosurgery-induced Malignant In An Arteriovenous Malformation PatientTakahiko Tsugawa1, Masaaki Yamamoto2, Bengt Karlsson3, Kentaro Fujii4, Hayato Tajima4, Tomotaka Ohsima4, Kyozo Kato41Kariya, Japan 2Ibaraki, Japan 3Singapore, Singapore 4 Katsuta Hospital Mito GammaHouse Keywords: gamma knife, cancer, arteriovenous malformation, oligodendroglioma, complications
Radiation-induced malignant glioma is extremely rare after gamma knife radiosurgery (GKRS) for arteriovenous malformations (AVMs).
We experienced an AVM patient in whom anaplastic oligodendroglioma occurred in the irradiated field after two sessions of GKRS.
A 19-year-old Japanese woman underwent GKRS for a right thalamic AVM, which had manifested with intracerebral hemorrhage, at the Karolinska Hospital on January 18, 1991. The second GKRS was performed at the Katsuta Hospital Mito GammaHouse on October 7, 2006.
The nidus (3.2 cc) was irradiated with a peripheral dose of 15.00 Gy (maximum: 30.0 Gy). Follow-up angiography performed on August 20, 1998, demonstrated remarkable nidus shrinkage but incomplete obliteration. Although a second GKRS was recommended, she refused it. After an uneventful eight-year-period, she experienced severe headache on July 28, 2006. CT scan demonstrated intracerebral hemorrhage and DSA showed a residual AVM. During the second GKRS, the residual nidus (0.5 cc, 16% of the original volume) was irradiated with a peripheral dose of 21.00 Gy (maximum: 30.00 Gy). She experienced her left-hand clumsiness at the beginning of April 2007 and retroocular pain occurred on April 23, 2007. CT scan showed an intracerebral hemorrhage. During the subsequent two-month period, her left hemi-motor weakness worsened. MR imaging performed on June 18, 2008, demonstrated an enhanced mass lesion with a cyst in the right temporal lobe. Extensive neuro-imaging studies, i.e., Tl-SPECT, MR spectrograph and DOPA-PET, suggested malignant brain tumor. She underwent surgical removal. Pathological findings were consistent with an anaplastic oligodendroglioma.
Although she received fractionated radiotherapy with a total dose of 60Gy followed by temozolamide treatment, she died on May 20, 2009.
This is a retrospective case report.
To the best of our knowledge, this patient represents the third malignant glioma arising at the site of AVM radiosurgery.
The risk of malignancy is low. Cases should continue to be reported. Project Roles:
T. Tsugawa (), M. Yamamoto (), B. Karlsson (), K. Fujii (), H. Tajima (), T. Ohsima (), K. Kato ()