title: Dual-Phase Dual-Energy CT in Patients Treated with Erlotinib for Advanced Non-Small Cell Lung Cancer: Possible Benefits of Iodine Quantification in Response Assessment.
abstract: OBJECTIVE
  To investigate the relationship of dual-phase dual-energy CT (DE-CT) and tumour size in the evaluation of the response to anti-EGFR therapy in patients with advanced non-small cell lung cancer (NSCLC).
  
  
  METHODS
  Dual-phase DE-CT was performed in 31 patients with NSCLC before the onset of anti-EGFR (erlotinib) therapy and as follow-up (mean 8 weeks). Iodine uptake (IU; mg/mL) was quantified using prototype software in arterial and venous phases; arterial enhancement fraction (AEF) was calculated. The change of IU before and after therapy onset was compared with anatomical evaluation in maximal transverse diameter and volume (responders vs. non-responders).
  
  
  RESULTS
  A significant decrease of IU in venous phase was proved in responders according to all anatomical parameters (p=0.002-0.016). In groups of non-responders, a significant change of IU was not proved with variable trends of development. The most significant change was observed using the anatomical parameter of volume (cut-off 73 %). A significant difference of percentage change in AEF was proved between responding and non-responders (p=0.019-0.043).
  
  
  CONCLUSIONS
  Dual-phase DE-CT with iodine uptake quantification is a feasible method with potential benefit in advanced assessment of anti-EGFR therapy response. We demonstrated a decrease in vascularization in the responding primary tumours and non-significant variable development of vascularization in non-responding tumours.
  
  
  CONCLUSIONS
  • Dual-phase DE-CT is feasible for vascularization assessment of NSCLC with anti-EGFR therapy. • There was a significant decrease of iodine uptake in responding tumours. • There was a non-significant and variable development in non-responding tumours. • There was significant difference of AEF percentage change between responders and non-responders.
authors.affiliation: Department of Imaging Methods, Faculty of Medicine and University Teaching Hospital in Pilsen, Pilsen, Czech Republic. baxaj@fnplzen.cz.
authors.forename: Jan
authors.initials: J
authors.lastname: Baxa
authors.affiliation: Department of Imaging Methods, Faculty of Medicine and University Teaching Hospital in Pilsen, Pilsen, Czech Republic.
authors.forename: Tana
authors.initials: T
authors.lastname: Matouskova
authors.affiliation: Department of Pulmonary Diseases, Faculty of Medicine and University Teaching Hospital in Pilsen, Pilsen, Czech Republic.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Krakorova
authors.affiliation: Siemens Healthcare, CT division, Forchheim, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Schmidt
authors.affiliation: Siemens Healthcare, CT division, Forchheim, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Flohr
authors.affiliation: Siemens Healthcare, CT division, Forchheim, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Sedlmair
authors.affiliation: Department of Imaging Methods, Faculty of Medicine and University Teaching Hospital in Pilsen, Pilsen, Czech Republic.
authors.forename: Jiri
authors.initials: J
authors.lastname: Bejcek
authors.affiliation: Department of Imaging Methods, Faculty of Medicine and University Teaching Hospital in Pilsen, Pilsen, Czech Republic.
authors.forename: Jiri
authors.initials: J
authors.lastname: Ferda
mesh_terms: D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis / Q000188:drug therapy* / Q000556:secondary; D000069347:Erlotinib Hydrochloride / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007455:Iodine; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000473:pathology; D008198:Lymph Nodes / Q000000981:diagnostic imaging*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography / Q000379:methods*; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D000970:Antineoplastic Agents; D007455:Iodine; D000069347:Erlotinib Hydrochloride
keywords: Dual-energy CT; Iodine contrast medium; Lung cancer; Targeted molecular therapy; Therapy response