title: Can dynamic MR imaging predict response in patients with rectal cancer undergoing cetuximab-based neoadjuvant chemoradiation?
abstract: BACKGROUND
  The aim of this study was to evaluate therapy response in patients undergoing cetuximab-CapIri-based chemoradiation for rectal cancer using dynamic magnetic resonance imaging (dMRI).
  
  
  METHODS
  The volumetric degree of tumor regression and contrast media perfusion were compared to the results of the histopathologic ypTN staging. 33 patients were examined using a 1.5-T scanner with repetitive 2D FLASH sequences after contrast media application. All patients were examined twice - before therapy and immediately before surgery.
  
  
  RESULTS
  In all patients, the tumor volume decreased (mean 72 +/- 16%). In 25/33 patients, the slope of the contrast media enhancement curve decreased (mean 31 +/- 20%). In histopathologically proven downstaging after therapy, the decrease in slope was significantly higher than in the group without downstaging, and the decrease in slope was better for distinguishing between 'responder' and 'non-responder' than the decrease in volume.
  
  
  CONCLUSIONS
  Using dMRI helps to identify responders undergoing cetuximab-based chemoradiation better than volume decrease alone.
authors.affiliation: Institut für Klinische Radiologie und Nuklearmedizin, Medizinische Fakultät Mannheim der Universität Heidelberg, Heidelberg, Germany. dietmar.dinter@medma.uni-heidelberg.de
authors.forename: Dietmar J
authors.initials: DJ
authors.lastname: Dinter
authors.forename: Karoline
authors.initials: K
authors.lastname: Horisberger
authors.forename: Christian
authors.initials: C
authors.lastname: Zechmann
authors.forename: Frederik
authors.initials: F
authors.lastname: Wenz
authors.forename: Joachim
authors.initials: J
authors.lastname: Brade
authors.forename: Frank
authors.initials: F
authors.lastname: Willeke
authors.forename: K Wolfgang
authors.initials: KW
authors.lastname: Neff
authors.forename: Stefan O
authors.initials: SO
authors.lastname: Schoenberg
authors.forename: Ralf-Dieter
authors.initials: RD
authors.lastname: Hofheinz
mesh_terms: D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000008:administration & dosage; D000068818:Cetuximab; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D018714:Radiotherapy, Adjuvant / Q000379:methods; D020266:Radiotherapy, Conformal; D012004:Rectal Neoplasms / Q000175:diagnosis* / Q000628:therapy*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D000068818:Cetuximab