title: Residual low ADC and high FA at the resection margin correlate with poor chemoradiation response and overall survival in high-grade glioma patients.
abstract: OBJECTIVE
  We hypothesized that ADC and FA of enhancing tumor (ET) and/or non-enhancing tumor (NT) adjacent to the operative resection margin before and during temozolomide and/or chemoradiation may allow prediction of chemoradiation response and patient survival.
  
  
  METHODS
  DTI was acquired in 37 patients with newly diagnosed HGG at two time points: after resection at the time of pre-RT planning MRI (Baseline) and after 30Gy of radiation therapy (mid-RT). ADC and FA at each time point and change in ADC and FA between the two time points were assessed by hot spot method in both residual ET and NT within 2cm of the resection margin and correlated with overall survival (OS) using receiver operating characteristics (ROC) area under curve (AUC) analysis and log-rank testing.
  
  
  RESULTS
  At baseline NT ADC<104×10(-5)mm(2)/s was strongly correlated with shorter 15 month OS (95% CI: 227-412 days vs 492-695 days) compared to patients with higher ADC (AUC 0.82). There was good separation between the groups and significance at log-rank testing (p=0.0002). Baseline NT FA>0.257 also correlated with shorter OS (95% CI: 300-515 days vs 438-686 days), compared with patients with lower FA (AUC 0.74), but there was considerable overlap between the groups and non-significance at log-rank testing (p=0.089). Residual ET ADC increased significantly (p=0.0004) and FA decreased significantly (p=0.03) for all patients during early RT but the change in ADC and FA was less strongly correlated with OS than baseline NT metrics.
  
  
  CONCLUSIONS
  Post-operative pre-radiation baseline low ADC in non-enhancing tumor at the resection margin correlates strongly with worse treatment response and decreased overall survival in a heterogeneous sample of high grade glioma patients treated with radiation and/or temozolamide chemoradiation.
authors: Department of Radiology, The Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital, Zhengzhou, China. Electronic address: qjryq@126.com.
authors: Jinrong
authors: J
authors: Qu
authors: Department of Radiology, Dana-Farber Cancer Institute, Boston, MA, USA; Harvard Medical School, Boston, MA, USA.
authors: Lei
authors: L
authors: Qin
authors: Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, Boston, MA, USA.
authors: Suchun
authors: S
authors: Cheng
authors: Department of Radiology, Brigham and Women's Hospital, Boston, MA, USA.
authors: Katherine
authors: K
authors: Leung
authors: Department of Radiology, The Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital, Zhengzhou, China; Department of Radiology, Brigham and Women's Hospital, Boston, MA, USA.
authors: Xiang
authors: X
authors: Li
authors: Department of Radiology, The Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital, Zhengzhou, China.
authors: Hailiang
authors: H
authors: Li
authors: Departments of Neuroradiology (DJP, LSW, LA) and Neurosurgery (TJ), Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors: Jianping
authors: J
authors: Dai
authors: Departments of Neuroradiology (DJP, LSW, LA) and Neurosurgery (TJ), Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors: Tao
authors: T
authors: Jiang
authors: Department of Radiology, Brigham and Women's Hospital, Boston, MA, USA.
authors: Ayca
authors: A
authors: Akgoz
authors: MR R&D, Siemens Medical Solutions, Inc., Boston, MA, USA.
authors: Ravi
authors: R
authors: Seethamraju
authors: Institute of Automation Chinese Academy of Sciences, Beijing, China.
authors: Qifeng
authors: Q
authors: Wang
authors: Department of Radiology, Brigham and Women's Hospital, Boston, MA, USA.
authors: Rifaquat
authors: R
authors: Rahman
authors: Departments of Neuroradiology (DJP, LSW, LA) and Neurosurgery (TJ), Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors: Shaowu
authors: S
authors: Li
authors: Departments of Neuroradiology (DJP, LSW, LA) and Neurosurgery (TJ), Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors: Lin
authors: L
authors: Ai
authors: Institute of Automation Chinese Academy of Sciences, Beijing, China.
authors: Tianzi
authors: T
authors: Jiang
authors: Department of Radiology, Brigham and Women's Hospital, Boston, MA, USA; Department of Radiology, Dana-Farber Cancer Institute, Boston, MA, USA; Harvard Medical School, Boston, MA, USA. Electronic address: gsyoung@partners.org.
authors: Geoffrey S
authors: GS
authors: Young
mesh_terms: D019540:Area Under Curve; D001254:Astrocytoma / Q000473:pathology* / Q000628:therapy*; D059248:Chemoradiotherapy / Q000379:methods*; D003606:Dacarbazine / Q000031:analogs & derivatives / Q000627:therapeutic use; D005260:Female; D005909:Glioblastoma / Q000473:pathology / Q000628:therapy; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D016019:Survival Analysis; D000077204:Temozolomide; D016896:Treatment Outcome
chemical_list: D003606:Dacarbazine; D000077204:Temozolomide
keywords: Apparent diffusion coefficient; Fractional anisotropy; High grade glioma; Magnetic resonance imaging; Survival analysis