title: Prediction of Response to Concurrent Chemoradiotherapy with Temozolomide in Glioblastoma: Application of Immediate Post-Operative Dynamic Susceptibility Contrast and Diffusion-Weighted MR Imaging.
abstract: OBJECTIVE
  To determine whether histogram values of the normalized apparent diffusion coefficient (nADC) and normalized cerebral blood volume (nCBV) maps obtained in contrast-enhancing lesions detected on immediate post-operative MR imaging can be used to predict the patient response to concurrent chemoradiotherapy (CCRT) with temozolomide (TMZ).
  
  
  METHODS
  Twenty-four patients with GBM who had shown measurable contrast enhancement on immediate post-operative MR imaging and had subsequently undergone CCRT with TMZ were retrospectively analyzed. The corresponding histogram parameters of nCBV and nADC maps for measurable contrast-enhancing lesions were calculated. Patient groups with progression (n = 11) and non-progression (n = 13) at one year after the operation were identified, and the histogram parameters were compared between the two groups. Receiver operating characteristic (ROC) analysis was used to determine the best cutoff value for predicting progression. Progression-free survival (PFS) was determined with the Kaplan-Meier method and the log-rank test.
  
  
  RESULTS
  The 99th percentile of the cumulative nCBV histogram (nCBV C99) on immediate post-operative MR imaging was a significant predictor of one-year progression (p = 0.033). ROC analysis showed that the best cutoff value for predicting progression after CCRT was 5.537 (sensitivity and specificity were 72.7% and 76.9%, respectively). The patients with an nCBV C99 of < 5.537 had a significantly longer PFS than those with an nCBV C99 of ≥ 5.537 (p = 0.026).
  
  
  CONCLUSIONS
  The nCBV C99 from the cumulative histogram analysis of the nCBV from immediate post-operative MR imaging may be feasible for predicting glioblastoma response to CCRT with TMZ.
authors.affiliation: Department of Radiology, Seoul National University College of Medicine, Seoul 03080, Korea.
authors.forename: Eun Kyoung
authors.initials: EK
authors.lastname: Lee
authors.affiliation: Department of Radiology, Seoul National University College of Medicine, Seoul 03080, Korea. ; Center for Nanoparticle Research, Institute for Basic Science, and School of Chemical and Biological Engineering, Seoul National University, Seoul 08826, Korea.
authors.forename: Seung Hong
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Department of Radiology, Seoul National University College of Medicine, Seoul 03080, Korea.
authors.forename: Tae Jin
authors.initials: TJ
authors.lastname: Yun
authors.affiliation: Department of Radiology, Seoul National University College of Medicine, Seoul 03080, Korea.
authors.forename: Koung Mi
authors.initials: KM
authors.lastname: Kang
authors.affiliation: Department of Internal Medicine, Cancer Research Institute, Seoul National University College of Medicine, Seoul 03080, Korea.
authors.forename: Tae Min
authors.initials: TM
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Cancer Research Institute, Seoul National University College of Medicine, Seoul 03080, Korea.
authors.forename: Se-Hoon
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Neurosurgery, Seoul National University College of Medicine, Seoul 03080, Korea.
authors.forename: Chul-Kee
authors.initials: CK
authors.lastname: Park
authors.affiliation: Department of Pathology, Seoul National University College of Medicine, Seoul 03080, Korea.
authors.forename: Sung-Hye
authors.initials: SH
authors.lastname: Park
authors.affiliation: Department of Radiation Oncology, Cancer Research Institute, Seoul National University College of Medicine, Seoul 03080, Korea.
authors.forename: Il Han
authors.initials: IH
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D018906:Antineoplastic Agents, Alkylating / Q000627:therapeutic use*; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology; D001932:Brain Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000401:mortality; D059248:Chemoradiotherapy; D003606:Dacarbazine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D038524:Diffusion Magnetic Resonance Imaging; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D005909:Glioblastoma / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000401:mortality; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012372:ROC Curve; D011859:Radiography; D012189:Retrospective Studies; D000077204:Temozolomide
chemical_list: D018906:Antineoplastic Agents, Alkylating; D003606:Dacarbazine; D000077204:Temozolomide
keywords: Apparent diffusion coefficient; Cerebral blood volume; Glioblastoma; Histogram analysis; Temozolomide