title: Predictive value of diffusion-weighted magnetic resonance imaging during chemoradiotherapy for head and neck squamous cell carcinoma.
abstract: OBJECTIVE
  To evaluate diffusion-weighted (DWI) magnetic resonance imaging (MRI) for treatment prediction during chemoradiotherapy (CRT) of head and neck squamous cell carcinoma (HNC).
  
  
  METHODS
  Thirty patients with HNC underwent echo-planar DWI and anatomical MRI before and 2 and 4 weeks into CRT. Patient follow-up lasted 2 years post-CRT. Tumour ADC (DeltaADC) and volume changes (DeltaV) between baseline, and 2 and 4 weeks' follow-up were compared for lesions with recurrence versus complete remission (CR) using a Mann-Whitney U test. The predictive value of the DeltaADC and DeltaV for locoregional control (LRC) was examined with the Kaplan-Meier method. The study was approved by the local ethics committee. All patients gave written informed consent.
  
  
  RESULTS
  The DeltaADC in primary tumours and nodal metastases, 2 and 4 weeks after the start of CRT, was significantly lower in lesions with post-CRT recurrence than in lesions with CR (DeltaADC(2 weeks) and DeltaADC(4 weeks) for primary tumours, relative to nodal metastases: p < 0.0001). The DeltaV only showed a significant difference for primary tumours at 2 weeks (DeltaV(2 weeks): p = 0.03). The DeltaADC correlated significantly with 2-year LRC (p < 0.001); the DeltaV did not (p > 0.05).
  
  
  CONCLUSIONS
  DWI during CRT for HNC allows more accurate response prediction than anatomical imaging, correlating significantly with 2-year LRC.
authors.affiliation: Department of Radiology, University Hospitals Leuven, Leuven, Belgium. Vincent.Vandecaveye@uzleuven.be
authors.forename: Vincent
authors.initials: V
authors.lastname: Vandecaveye
authors.forename: Piet
authors.initials: P
authors.lastname: Dirix
authors.forename: Frederik
authors.initials: F
authors.lastname: De Keyzer
authors.forename: Katya Op
authors.initials: KO
authors.lastname: de Beeck
authors.forename: Vincent
authors.initials: V
authors.lastname: Vander Poorten
authors.forename: I
authors.initials: I
authors.lastname: Roebben
authors.forename: Sandra
authors.initials: S
authors.lastname: Nuyts
authors.forename: Robert
authors.initials: R
authors.lastname: Hermans
mesh_terms: D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy* / Q000532:radiotherapy*; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006258:Head and Neck Neoplasms / Q000188:drug therapy* / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D016896:Treatment Outcome; D047368:Tumor Burden