title: Malignant transformation of a vestibular schwannoma after gamma knife radiosurgery.
abstract: Stereotactic radiosurgery is used to treat benign tumours, but its long-term effects are not fully understood. Here we describe a vestibular schwannoma that underwent malignant transformation 6 years after gamma knife radiosurgery applied to the tumour remnant after a primary resection. Histological specimens of the original specimen did not show any atypical features. Genotyping showed a TP53 mutation in the recurrent tumour, which did not exist in the original tumour. Our results suggest that radiosurgery induced the malignant transformation, and we propose a cautious application of this treatment for benign tumours.
authors.affiliation: Department of Neurosurgery, University of Tokyo Hospital, Tokyo, Japan. shinmasa@ka2.so-net.ne.jp
authors.forename: Masahiro
authors.initials: M
authors.lastname: Shin
authors.forename: Keisuke
authors.initials: K
authors.lastname: Ueki
authors.forename: Hiroki
authors.initials: H
authors.lastname: Kurita
authors.forename: Takaaki
authors.initials: T
authors.lastname: Kirino
mesh_terms: D000328:Adult; D002471:Cell Transformation, Neoplastic / Q000235:genetics; D017809:Fatal Outcome; D005260:Female; D006801:Humans; D009364:Neoplasm Recurrence, Local / Q000235:genetics / Q000473:pathology*; D009464:Neuroma, Acoustic / Q000473:pathology* / Q000601:surgery; D016634:Radiosurgery / Q000009:adverse effects* / Q000295:instrumentation