title: Quantification of serial changes in cerebral blood volume and metabolism in patients with recurrent glioblastoma undergoing antiangiogenic therapy.
abstract: OBJECTIVE
  To evaluate the usefulness of quantitative advanced magnetic resonance imaging (MRI) methods for assessment of antiangiogenic therapy (AAT) response in recurrent glioblastoma multiforme (GBM).
  
  
  METHODS
  Eighteen patients with recurrent GBM received bevacizumab and 18 patients served as control group. Baseline MRI and two follow-up examinations were acquired every 3-5 months using dynamic susceptibility-weighted contrast (DSC) perfusion MRI and (1)H-MR spectroscopic imaging ((1)H-MRSI). Maps of absolute cerebral blood volume (aCBV) were coregistered with choline (Cho) and N-acetyl-aspartate (NAA) concentrations and compared to usually used relative parameters as well as controls.
  
  
  RESULTS
  Perfusion significantly decreased in responding and pseudoresponding GBMs but also in normal appearing brain after AAT onset. Cho and NAA concentrations were superior to Cr-ratios in lesion differentiation and showed a clear gap between responding and pseudoresponding lesions. Responders to AAT exceptionally frequently (6 out of 8 patients) showed remote GBM progression.
  
  
  CONCLUSIONS
  Quantification of CBV reveals changes in normal brain perfusion due to AAT, which were not described so far. DSC perfusion MRI seems not to be suitable for differentiation between response and pseudoresponse to AAT. However, absolute quantification of brain metabolites may allow for distinction due to a clear gap at 6-9 months after therapy onset.
authors: Institute of Medical Radiology, University Clinic of St. Pölten, Propst Führer-Straße 4, A-3100 St. Pölten, Austria; Department of Neurosurgery, University of Erlangen-Nuremberg, Schwabachanlage 6, D-91054 Erlangen, Germany; Department of Radiology and Nuclear Medicine, Medical University Vienna, Währinger Gürtel 18-20, A-1097 Vienna, Austria. Electronic address: andi@nmr.at.
authors: Andreas
authors: A
authors: Stadlbauer
authors: First Department of Internal Medicine, University Clinic of St. Pölten, Propst Führer-Straße 4, A-3100 St. Poelten, Austria.
authors: Petra
authors: P
authors: Pichler
authors: Institute of Medical Radiology, University Clinic of St. Pölten, Propst Führer-Straße 4, A-3100 St. Pölten, Austria.
authors: Marianne
authors: M
authors: Karl
authors: Department of Neurosurgery, University of Erlangen-Nuremberg, Schwabachanlage 6, D-91054 Erlangen, Germany.
authors: Sebastian
authors: S
authors: Brandner
authors: Institute of Medical Radiology, University Clinic of St. Pölten, Propst Führer-Straße 4, A-3100 St. Pölten, Austria.
authors: Claudia
authors: C
authors: Lerch
authors: Institute of Experimental and Clinical Pharmacology and Toxicology, University of Erlangen-Nürnberg, Erlangen, Germany.
authors: Bertold
authors: B
authors: Renner
authors: Institute of Medical Radiology, University Clinic of St. Pölten, Propst Führer-Straße 4, A-3100 St. Pölten, Austria.
authors: Gertraud
authors: G
authors: Heinz
mesh_terms: D020533:Angiogenesis Inhibitors / Q000627:therapeutic use*; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000187:drug effects / Q000378:metabolism; D000068258:Bevacizumab / Q000627:therapeutic use; D001810:Blood Volume / Q000187:drug effects*; D001921:Brain / Q000098:blood supply / Q000187:drug effects / Q000378:metabolism; D001931:Brain Mapping; D001932:Brain Neoplasms / Q000098:blood supply / Q000188:drug therapy* / Q000378:metabolism*; D002560:Cerebrovascular Circulation / Q000187:drug effects; D002794:Choline / Q000378:metabolism; D003287:Contrast Media / Q000627:therapeutic use; D005260:Female; D005500:Follow-Up Studies; D005909:Glioblastoma / Q000098:blood supply / Q000188:drug therapy* / Q000378:metabolism*; D006801:Humans; D018810:Magnetic Resonance Angiography; D008279:Magnetic Resonance Imaging / Q000379:methods; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000098:blood supply / Q000188:drug therapy / Q000378:metabolism; D015203:Reproducibility of Results
chemical_list: D020533:Angiogenesis Inhibitors; D003287:Contrast Media; D000068258:Bevacizumab; D001224:Aspartic Acid; C000179:N-acetylaspartate; D002794:Choline
keywords: Antiangiogenic therapy; Cerebral blood volume; MR spectroscopy; Quantitative MR imaging; Recurrent glioblastoma