title: A comparative study of the extent of cerebral microvascular injury following whole-brain irradiation versus reduced-field irradiation in long-term survivors of intracranial germ cell tumors.
abstract: OBJECTIVE
  Radiation-induced cerebral cavernous malformation reflects post-irradiation impairment of cerebral microcirculation. Our purpose was to determine effects of radiation field size and dose on the extent of developing cavernous malformations in long-term survivors of intracranial germ cell tumors (GCTs).
  
  
  METHODS
  The study involved 34 patients with a history of intracranial GCTs treated with either whole-brain or reduced-field irradiation and undergoing magnetic resonance (MR) imaging with a mean follow-up of 18.5 years. The number of cavernous malformations on T2*-weighted MR images between whole-brain and reduced-field irradiation groups as well as between high- (50.2 Gy) and low-dose (24.4 Gy) fields were compared.
  
  
  RESULTS
  A total of 235 cavernous malformation lesions were observed in 32 of 34 patients (94.1%). The mean number of lesions was 2.3 times as high in the whole-brain group as in the reduced-field group (P = 0.00296). The number of lesions in high-dose fields was significantly larger than in low-dose (P < 0.000001) or untreated fields (P < 0.001).
  
  
  CONCLUSIONS
  Radiation field size and dose were positively associated with the number of cavernous malformations developed. Cavernous malformations detected on MR imaging can be used as a surrogate marker for microvascular injury following intracranial irradiation in long-term cancer survivors.
authors.affiliation: Department of Diagnostic Radiology, Graduate School of Medicine, Tohoku University, Japan; Department of Radiation Oncology, Graduate School of Medicine, Tohoku University, Japan.
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Diagnostic Radiology, Graduate School of Medicine, Tohoku University, Japan. Electronic address: mugi@rad.med.tohoku.ac.jp.
authors.forename: Shunji
authors.initials: S
authors.lastname: Mugikura
authors.affiliation: Department of Neurosurgery, Graduate School of Medicine, Tohoku University, Japan.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Kumabe
authors.affiliation: Department of Diagnostic Radiology, Graduate School of Medicine, Tohoku University, Japan.
authors.forename: Takaki
authors.initials: T
authors.lastname: Murata
authors.affiliation: Department of Behavioral Neurology and Cognitive Neuroscience, Graduate School of Medicine, Tohoku University, Japan.
authors.forename: Etsuro
authors.initials: E
authors.lastname: Mori
authors.affiliation: Department of Diagnostic Radiology, Graduate School of Medicine, Tohoku University, Japan.
authors.forename: Kei
authors.initials: K
authors.lastname: Takase
authors.affiliation: Department of Radiation Oncology, Graduate School of Medicine, Tohoku University, Japan.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Jingu
authors.affiliation: Department of Diagnostic Radiology, Graduate School of Medicine, Tohoku University, Japan.
authors.forename: Shoki
authors.initials: S
authors.lastname: Takahashi
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000098:blood supply / Q000473:pathology / Q000528:radiation effects; D001932:Brain Neoplasms / Q000532:radiotherapy*; D002648:Child; D016371:Cranial Irradiation / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D020786:Hemangioma, Cavernous, Central Nervous System / Q000209:etiology* / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D055806:Microvessels / Q000528:radiation effects; D009373:Neoplasms, Germ Cell and Embryonal / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D017741:Survivors; D055815:Young Adult
keywords: Cranial irradiation; Germinoma; Long-term cancer survivors; Pediatric cancer; Radiation-induced cavernous malformation