title: Early treatment response in non-small cell lung cancer patients using diffusion-weighted imaging and functional diffusion maps--a feasibility study.
abstract: OBJECTIVE
  The aim of this study was to prospectively evaluate the feasibility of monitoring treatment response to chemotherapy in patients with non-small cell lung carcinoma using functional diffusion maps (fDMs).
  
  
  METHODS
  This study was approved by the Cantonal Research Ethics Committee and informed written consent was obtained from all patients. Nine patients (mean age = 66 years; range = 53-76 years, 5 females, 4 males) with overall 13 lesions were included. Imaging was performed within two weeks before initiation of chemotherapy and at one, two, and six weeks after initiation of chemotherapy. Imaging included a respiratory-triggered diffusion-weighted sequence including three b-factors (100, 600, and 800 s/mm2). Treatment response was defined by change in tumor diameter on computed tomography (CT) after two cycles of chemotherapy. Changes in the apparent diffusion coefficient (ADC) on a per-lesion basis and the percentages of voxel with significantly increased or decreased ADCs on fDMs were analyzed using repeated measures analysis of variance (ANOVA). Changes in tumor size were used as covariate to examine the ability of ADCs and fDM parameters to predict treatment response.
  
  
  RESULTS
  Repeated measures ANOVA revealed that the percentage of voxels with increased ADCs on fDMs (p = 0.002) as well as the mean ADC increase (p = 0.011) were significantly higher in good responders with a large reduction in tumor size on CT.
  
  
  CONCLUSIONS
  Our results indicate that the percentage of voxels with significantly increased ADCs on fDMs seems to be a promising biomarker for early prediction of treatment response in patients with non-small cell lung carcinoma. Contrary to averaged values, this approach allows the spatial heterogeneity of treatment response to be resolved.
authors.affiliation: Institute of Radiology and Nuclear Medicine, Clinical Research Unit, Hirslanden Hospital St. Anna, Lucerne, Switzerland; Department of Radiology, Cantonal Hospital Winterthur, Winterthur, Switzerland; Department of Radiology, Paracelsus Medical University Salzburg, Salzburg, Austria.
authors.forename: Carolin
authors.initials: C
authors.lastname: Reischauer
authors.affiliation: Institute of Radiology and Nuclear Medicine, Clinical Research Unit, Hirslanden Hospital St. Anna, Lucerne, Switzerland.
authors.forename: Johannes Malte
authors.initials: JM
authors.lastname: Froehlich
authors.affiliation: Department of Oncology, Cantonal Hospital Winterthur, Winterthur, Switzerland.
authors.forename: Miklos
authors.initials: M
authors.lastname: Pless
authors.affiliation: Department of Radiology, Paracelsus Medical University Salzburg, Salzburg, Austria.
authors.forename: Christoph Andreas
authors.initials: CA
authors.lastname: Binkert
authors.affiliation: Academic Department of Radiology, Royal Marsden NHS Foundation Trust, Sutton, Surrey, United Kingdom; CR-UK and EPSRC Cancer Imaging Centre, Institute of Cancer Research, Sutton, Surrey, United Kingdom.
authors.forename: Dow-Mu
authors.initials: DM
authors.lastname: Koh
authors.affiliation: Institute of Radiology and Nuclear Medicine, Clinical Research Unit, Hirslanden Hospital St. Anna, Lucerne, Switzerland; Department of Radiology, Paracelsus Medical University Salzburg, Salzburg, Austria.
authors.forename: Andreas
authors.initials: A
authors.lastname: Gutzeit
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis* / Q000188:drug therapy*; D038524:Diffusion Magnetic Resonance Imaging; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D047368:Tumor Burden