title: Second-look surgery for intracranial germ cell tumors.
abstract: BACKGROUND
  The role of second-look surgery in intracranial germ cell tumors (GCTs) needs to be reviewed.
  
  
  OBJECTIVE
  To present our experience of second-look surgery in patients with intracranial GCTs who showed less than complete response despite normalizing or decreasing tumor markers after chemotherapy.
  
  
  METHODS
  Retrospective review of 7 patients who underwent second-look surgery for an intracranial GCT was performed.
  
  
  RESULTS
  Of 23 consecutive patients with newly diagnosed intracranial GCTs treated between August 2003 and August 2013, 7 patients (30%) underwent second-look surgery. The mean age was 9.4 years. The initial diagnoses were mixed germ cell tumor in 5 and immature teratoma in 2. Second-look surgery was performed after 1 to 3 courses of chemotherapy. Magnetic resonance imaging at the surgery demonstrated increasing residual tumor in 4 and stable residual tumor in 3. Tumor markers were normalized in 5 and nearly normalized in 2. Gross total resection was achieved in all patients. Histopathology at second-look surgery revealed mature teratoma in 5, fibrosis with atypical cells in 1, and fibrosis in 1. All patients subsequently underwent additional chemoradiation therapy according to the initial diagnosis. All patients are alive with no evidence of recurrence, with a mean follow-up of 48 months.
  
  
  CONCLUSIONS
  Second-look surgery plays an important role in the treatment of intracranial GCTs. Surgery may be encouraged at a relatively early phase after chemotherapy when the residual tumor increases or does not change size despite normalized or nearly normalized tumor markers in order to achieve complete resection and improve outcome.
authors.affiliation: *Division of Neurosurgery, National Center for Child Health and Development, Tokyo, Japan; ‡Division of NeuroOncology, National Center for Child Health and Development, Tokyo, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Ogiwara
authors.forename: Chikako
authors.initials: C
authors.lastname: Kiyotani
authors.forename: Keita
authors.initials: K
authors.lastname: Terashima
authors.forename: Nobuhito
authors.initials: N
authors.lastname: Morota
mesh_terms: D014408:Biomarkers, Tumor; D001932:Brain Neoplasms / Q000601:surgery*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000601:surgery; D018365:Neoplasm, Residual / Q000601:surgery; D009373:Neoplasms, Germ Cell and Embryonal / Q000601:surgery*; D012074:Remission Induction; D012189:Retrospective Studies; D024162:Second-Look Surgery
chemical_list: D014408:Biomarkers, Tumor