title: Validation of optimal DCE-MRI perfusion threshold to classify at-risk tumor imaging voxels in heterogeneous cervical cancer for outcome prediction.
abstract: OBJECTIVE
  To classify tumor imaging voxels at-risk for treatment failure within the heterogeneous cervical cancer using DCE MRI and determine optimal voxel's DCE threshold values at different treatment time points for early prediction of treatment failure.
  
  
  METHODS
  DCE-MRI from 102 patients with stage IB2-IVB cervical cancer was obtained at 3 different treatment time points: before (MRI 1) and during treatment (MRI 2 at 2-2.5 weeks and MRI 3 at 4-5 weeks). For each tumor voxel, the plateau signal intensity (SI) was derived from its time-SI curve from the DCE MRI. The optimal SI thresholds to classify the at-risk tumor voxels was determined by the maximal area under the curve using ROC analysis when varies SI value from 1.0 to 3.0 and correlates with treatment outcome.
  
  
  RESULTS
  The optimal SI thresholds for MRI 1, 2 and 3 were 2.2, 2.2 and 2.1 for significant differentiation between local recurrence/control, respectively, and 1.8, 2.1 and 2.2 for death/survival, respectively.
  
  
  CONCLUSIONS
  Optimal SI thresholds are clinically validated to quantify at-risk tumor voxels which vary with time. A single universal threshold (SI=1.9) was identified for all 3 treatment time points and remained significant for the early prediction of treatment failure.
authors.affiliation: Department of Radiation Oncology, East Carolina University, Greenville, NC; Department of Radiation Oncology, Ohio State University, Columbus, OH.
authors.forename: Zhibin
authors.initials: Z
authors.lastname: Huang
authors.affiliation: Department of Radiation Oncology, East Carolina University, Greenville, NC; Department of Radiation Oncology, Ohio State University, Columbus, OH.
authors.forename: Kevin A
authors.initials: KA
authors.lastname: Yuh
authors.affiliation: Department of Radiation Oncology, Case Western Reserve University, Cleveland, OH.
authors.forename: Simon S
authors.initials: SS
authors.lastname: Lo
authors.affiliation: Department of Radiation Oncology, Ohio State University, Columbus, OH.
authors.forename: John C
authors.initials: JC
authors.lastname: Grecula
authors.affiliation: Department of Radiology, Ohio State University, Columbus, OH; Department of Radiology, University of Chicago, Chicago, Il.
authors.forename: Steffen
authors.initials: S
authors.lastname: Sammet
authors.affiliation: Department of Medical Imaging, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Il.
authors.forename: Christina L
authors.initials: CL
authors.lastname: Sammet
authors.affiliation: Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA.
authors.forename: Guang
authors.initials: G
authors.lastname: Jia
authors.affiliation: Department of Radiology, Ohio State University, Columbus, OH.
authors.forename: Michael V
authors.initials: MV
authors.lastname: Knopp
authors.affiliation: Department of Biostatistics, East Carolina University, Greenville, NC.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wu
authors.affiliation: Department of Radiology, University of Washington, Seattle, WA.
authors.forename: Norman J
authors.initials: NJ
authors.lastname: Beauchamp
authors.affiliation: Department of Radiology, Ohio State University, Columbus, OH; Department of Radiology, University of Washington, Seattle, WA.
authors.forename: William T C
authors.initials: WT
authors.lastname: Yuh
authors.affiliation: Department of Radiation Oncology, Ohio State University, Columbus, OH.
authors.forename: Roy
authors.initials: R
authors.lastname: Wang
authors.affiliation: Department of Radiation Oncology, Ohio State University, Columbus, OH; Department of Radiation Oncology, University of Washington, Seattle, WA. Electronic address: ninamayr@uw.edu.
authors.forename: Nina A
authors.initials: NA
authors.lastname: Mayr
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008833:Microcirculation; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D010477:Perfusion; D012372:ROC Curve; D016896:Treatment Outcome; D002583:Uterine Cervical Neoplasms / Q000175:diagnosis* / Q000473:pathology*
keywords: Cervical cancer; Image analysis; Microcirculation; Perfusion imaging; Radiation therapy; Resistant tumor cell