title: Early imaging findings in germ cell tumors arising from the basal ganglia.
abstract: BACKGROUND
  It is difficult to diagnosis early stage germ cell tumors originating in the basal ganglia, but early recognition is important for better outcome.
  
  
  OBJECTIVE
  To evaluate serial MR images of basal ganglia germ cell tumors, with emphasis on the features of early stage tumors.
  
  
  METHODS
  We retrospectively reviewed serial MR images of 15 tumors in 14 children and young adults. We categorized MR images of the tumors as follows: type I, ill-defined patchy lesions (<3 cm) without cyst; type II, small mass lesions (<3 cm) with cyst; and type III, large lesions (≥3 cm) with cyst. We also assessed temporal changes of the MR images.
  
  
  RESULTS
  On the initial images, 8 of 11 (73%) type I tumors progressed to types II or III, and 3 of 4 (75%) type II tumors progressed to type III. The remaining 4 tumors did not change in type. All type II tumors (5/5, 100%) that changed from type I had a few tiny cysts. Intratumoral hemorrhage was observed even in the type I tumor. Ipsilateral hemiatrophy was observed in most of the tumors (13/15, 87%) on initial MR images. As tumors grew, cystic changes, intratumoral hemorrhage, and ipsilateral hemiatrophy became more apparent.
  
  
  CONCLUSIONS
  Early stage basal ganglia germ cell tumors appear as ill-defined small patchy hyperintense lesions without cysts on T2-weighted images, are frequently associated with ipsilateral hemiatrophy, and sometimes show microhemorrhage. Tumors develop tiny cysts at a relatively early stage.
authors.affiliation: Department of Radiology, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-769, Republic of Korea.|Department of Radiology, Kyungpook National University Medical Center, 807 Hoguk-ro, Buk-gu, Daegu, 41404, Republic of Korea.
authors.forename: So Mi
authors.initials: SM
authors.lastname: Lee
authors.affiliation: Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-769, Republic of Korea. kimio@snu.ac.kr.
authors.forename: In-One
authors.initials: IO
authors.lastname: Kim
authors.affiliation: Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-769, Republic of Korea.
authors.forename: Young Hun
authors.initials: YH
authors.lastname: Choi
authors.affiliation: Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-769, Republic of Korea.
authors.forename: Jung-Eun
authors.initials: JE
authors.lastname: Cheon
authors.affiliation: Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-769, Republic of Korea.
authors.forename: Woo Sun
authors.initials: WS
authors.lastname: Kim
authors.affiliation: Department of Radiology, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-769, Republic of Korea.|Department of Radiology, Ewha Woman's University Mokdong Hospital, Seoul, South Korea.
authors.forename: Hyun-Hae
authors.initials: HH
authors.lastname: Cho
authors.affiliation: Department of Radiology, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-769, Republic of Korea.|Department of Radiology, Chungnam National University Hospital, Daejeon, Republic of Korea.
authors.forename: Sun Kyoung
authors.initials: SK
authors.lastname: You
mesh_terms: D000293:Adolescent; D001479:Basal Ganglia / Q000000981:diagnostic imaging* / Q000473:pathology*; D001932:Brain Neoplasms / Q000000981:diagnostic imaging*; D002648:Child; D003937:Diagnosis, Differential; D018450:Disease Progression; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009373:Neoplasms, Germ Cell and Embryonal / Q000000981:diagnostic imaging*; D012189:Retrospective Studies; D055815:Young Adult
keywords: Adolescent; Basal ganglia; Child; Early stage; Germ cell tumor; Magnetic resonance imaging; Serial images