title: Dynamic contrast-enhanced computed tomography to assess early activity of cetuximab in squamous cell carcinoma of the head and neck.
abstract: BACKGROUND
  Cetuximab, a monoclonal antibody targeting the Epidermal Growth Factor Receptor (EGFR), has demonstrated activity in various tumor types. Using dynamic contrast-enhanced computed tomography (DCE-CT), we investigated the early activity of cetuximab monotherapy in previously untreated patients with squamous cell carcinoma of the head and neck (SCCHN).
  
  
  METHODS
  Treatment-naïve patients with SCCHN received cetuximab for 2 weeks before curative surgery. Treatment activity was evaluated by DCE-CT at baseline and before surgery. Tumor vascular and interstitial characteristics were evaluated using the Brix two-compartment kinetic model. Modifications of the perfusion parameters (blood flow Fp, extravascular space ve, vascular space vp, and transfer constant PS) were assessed between both time points. DCE data were compared to FDG-PET and histopathological examination obtained simultaneously. Plasmatic vascular markers were investigated at different time points.
  
  
  RESULTS
  Fourteen patients had evaluable DCE-CT parameters at both time points. A significant increase in the extravascular extracellular space ve accessible to the tracer was observed but no significant differences were found for the other kinetic parameters (Fp, vp or PS). Significant correlations were found between DCE parameters and the other two modalities. Plasmatic VEGF, PDGF-BB and IL-8 decreased as early as 2 hours after cetuximab infusion.
  
  
  CONCLUSIONS
  Early activity of cetuximab on tumor interstitial characteristics was detected by DCE-CT. Modifications of plasmatic vascular markers are not sufficient to confirm anti-angiogenic cetuximab activity in vivo. Further investigation is warranted to determine to what extent DCE-CT parameters are modified and to evaluate whether they are able to predict treatment outcome.
authors: Department of Medical Oncology and Head and Neck Surgery, Cliniques Universitaires Saint-Luc and Institut de Recherche Clinique et Expérimentale (Pole MIRO), Université Catholique de Louvain, Brussels, Belgium.
authors: Sandra
authors: S
authors: Schmitz
authors: Department of Medical Imaging and Radiology, Cliniques Universitaires Saint-Luc and Institut de Recherche Clinique et Expérimentale (Pole IMAG), Université Catholique de Louvain, Brussels, Belgium.
authors: Denis
authors: D
authors: Rommel
authors: Department of Medical Imaging and Radiology, Cliniques Universitaires Saint-Luc and Institut de Recherche Clinique et Expérimentale (Pole IMAG), Université Catholique de Louvain, Brussels, Belgium.
authors: Nicolas
authors: N
authors: Michoux
authors: Department of Nuclear Medicine, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Brussels, Belgium.
authors: Renaud
authors: R
authors: Lhommel
authors: Department of Nuclear Medicine, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Brussels, Belgium.
authors: François-Xavier
authors: FX
authors: Hanin
authors: Department of Medical Imaging and Radiology, Cliniques Universitaires Saint-Luc and Institut de Recherche Clinique et Expérimentale (Pole IMAG), Université Catholique de Louvain, Brussels, Belgium.
authors: Thierry
authors: T
authors: Duprez
authors: Department of Medical Oncology and Head and Neck Surgery, Cliniques Universitaires Saint-Luc and Institut de Recherche Clinique et Expérimentale (Pole MIRO), Université Catholique de Louvain, Brussels, Belgium.
authors: Jean-Pascal
authors: JP
authors: Machiels
keywords: DCE-CT; cetuximab; head and neck cancer; perfusion