title: Comparison of neuroendocrine tumor detection and characterization using DOTATOC-PET in correlation with contrast enhanced CT and delayed contrast enhanced MRI.
abstract: OBJECTIVE
  We evaluated the rate of successful characterization of gastroenteropancreatic neuroendocrine tumors (NETs) present with an increased somatostatin receptor, comparing CE-CT with CE-MRI, each in correlation with DOTATOC-PET.
  
  
  METHODS
  8 patients with GEP-NET were imaged using CE-MRI (Gd-EOB-DTPA), CE-CT (Imeron 400) and DOTATOC-PET. Contrast-enhancement of normal liver-tissue and metastasis was quantified with ROI-technique. Tumor delineation was assessed with visual-score in blind-read-analysis by two experienced radiologists.
  
  
  RESULTS
  Out of 40 liver metastases in patients with NETs, all were detected by CE-MRI and the lesion extent could be adequately assessed, whereas CT failed to detect 20% of all metastases. The blind-read-score of CT in arterial and portal phase was median -0.65 and -1.4, respectively, and 2.7 for delayed-MRI. The quantitative ROI-analysis presented an improved contrast-enhancement-ratio with a median of 1.2, 1.6 and 3.3 for CE-CT arterial, portal-phase and delayed-MRI respectively.
  
  
  CONCLUSIONS
  Late CE-MRI was superior to CE-CT in providing additionally morphologic characterization and exact lesion extension of hepatic metastases from neuroendocrine tumor detected with DOTATOC-PET. Therefore, late enhanced Gd-EOB-DTPA-MRI seems to be the adequate imaging modality for combination with DOTATOC-PET to provide complementary (macroscopic and molecular) tumor characterization in hepatic metastasized NETs.
authors.affiliation: Department of Nuclear Medicine, University Hospital Heidelberg, INF 400, 69120 Heidelberg, Germany. f.giesel@dkfz.de
authors.forename: F L
authors.initials: FL
authors.lastname: Giesel
authors.forename: C
authors.initials: C
authors.lastname: Kratochwil
authors.forename: A
authors.initials: A
authors.lastname: Mehndiratta
authors.forename: S
authors.initials: S
authors.lastname: Wulfert
authors.forename: J H
authors.initials: JH
authors.lastname: Moltz
authors.forename: C M
authors.initials: CM
authors.lastname: Zechmann
authors.forename: H U
authors.initials: HU
authors.lastname: Kauczor
authors.forename: U
authors.initials: U
authors.lastname: Haberkorn
authors.forename: S
authors.initials: S
authors.lastname: Ley
mesh_terms: D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D019786:Gadolinium DTPA / Q000008:administration & dosage; D006801:Humans; D007205:Indium Radioisotopes; D007479:Iopamidol / Q000008:administration & dosage / Q000031:analogs & derivatives*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D018358:Neuroendocrine Tumors / Q000175:diagnosis*; D015282:Octreotide / Q000031:analogs & derivatives*; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007205:Indium Radioisotopes; D019275:Radiopharmaceuticals; C073590:gadolinium ethoxybenzyl DTPA; C057937:iomeprol; D007479:Iopamidol; D019786:Gadolinium DTPA; D015282:Octreotide; C106246:Edotreotide