title: Pilot study on the detection of antiandrogen resistance using serial diffusion-weighted imaging of bone metastases in prostate cancer.
abstract: To evaluate serial apparent diffusion coefficient (ADC) measurements of bone metastases in prostate cancer to determine whether antiandrogen resistance can be detected and time to progression estimated.
  
  
  
  Diffusion-weighted imaging (DWI) was performed at 1.5T in nine patients with treatment-naïve metastatic prostate cancer (20 lesions) before antiandrogen treatment, after 1, 2, and 3 months of treatment, and thereafter every 4 months over 31 months or until antiandrogen resistance was detected. Tumor volumes were stable over time. Time courses of the ADCs when averaged over entire lesions and on functional diffusion maps (fDMs) were analyzed using marginal linear model (MLM) analysis.
  
  
  
  Starting at 1 month, MLM analysis revealed decreasing mean ADCs (P = 0.001) over time. Simultaneously, the percentage of voxels with significantly higher ADCs decreased (P = 0.004), whereas the percentage of voxels with significantly lower ADCs increased (P < 0.001) on fDMs. Both mean ADCs (P = 0.042) and percentages of voxels with significantly higher ADCs on fDMs (P = 0.039) decreased more rapidly over time in patients with a shorter progression-free interval (PFI). Likewise, higher (P = 0.001) and more rapidly increasing (P = 0.002) percentages of voxels with significantly lower ADCs on fDMs were associated with a shorter PFI.
  
  
  
  The results of our pilot study suggest that the evolution of ADCs over time may permit early identification of antiandrogen resistance in bone metastases. J. Magn. Reson. Imaging 2016;43:1407-1416.
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.|Institute for Biomedical Engineering, ETH and University of Zurich, Zurich, Switzerland.
authors.forename: Carolin
authors.initials: C
authors.lastname: Reischauer
authors.affiliation: Academic Department of Radiology, Royal Marsden NHS Foundation Trust, Sutton, Surrey, UK.|CR-UK and EPSRC Cancer Imaging Centre, Institute of Cancer Research, Sutton, Surrey, UK.
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.
authors.forename: Johannes M
authors.initials: JM
authors.lastname: Froehlich
authors.affiliation: Department of Radiology, Cantonal Hospital Winterthur, Winterthur, Switzerland.
authors.forename: René
authors.initials: R
authors.lastname: Patzwahl
authors.affiliation: Department of Radiology, Cantonal Hospital Winterthur, Winterthur, Switzerland.
authors.forename: Christoph A
authors.initials: CA
authors.lastname: Binkert
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.|Department of Radiology, Cantonal Hospital Winterthur, Winterthur, Switzerland.
authors.forename: Andreas
authors.initials: A
authors.lastname: Gutzeit
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000726:Androgen Antagonists / Q000008:administration & dosage*; D000970:Antineoplastic Agents / Q000008:administration & dosage; D001859:Bone Neoplasms / Q000188:drug therapy* / Q000473:pathology / Q000556:secondary*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D016903:Drug Monitoring / Q000379:methods*; D019008:Drug Resistance, Neoplasm; D006801:Humans; D008297:Male; D010865:Pilot Projects; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000473:pathology; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome
chemical_list: D000726:Androgen Antagonists; D000970:Antineoplastic Agents
keywords: antiandrogen resistance; apparent diffusion coefficient; bone metastasis; diffusion-weighted imaging; functional diffusion map; prostate cancer