title: Accuracy of multislice liver CT and MRI for preoperative assessment of colorectal liver metastases after neoadjuvant chemotherapy.
abstract: BACKGROUND
  To determine the best imaging modality for preoperative detection, characterization and measurement of colorectal liver metastases (CRLM) after neoadjuvant chemotherapy (NAC).
  
  
  METHODS
  A total of 79 lesions in 15 patients with CRLM were included. Following NAC, all patients received multislice liver CT (MSCT) and magnetic resonance imaging (MRI) that were scored by two observers for lesion number, type, diameter (mm) and segmental location. Intraoperative findings, histopathology and follow-up imaging were used as reference standard for surgically treated patients; non-surgical candidates underwent follow-up imaging.
  
  
  RESULTS
  Lesion detection rate was similar for MSCT and MRI (76 and 80%, respectively, p = 0.648). Lesion characterization was significantly superior (p = 0.021) at MRI (89%, κ 0.747, p = 0.001) compared to MSCT (77%, κ 0.235, p = 0.005). Interobserver variability for diameter measurement was not significant at MRI (p = 0.909 [95% CI -1.245 to 1.395]), but significant at MSCT (p = 0.028 [95% CI -3.349 to -2.007]). Differences in diameter measurement were independent of observer (p = 0.131), and no statistical effect from imaging modality on diameter measurement was observed (p = 0.095).
  
  
  CONCLUSIONS
  MRI is superior to MSCT in preoperative characterization and measurement of CRLM after NAC. Lesion detection rates for both modalities are comparable.
authors.affiliation: Department of Surgery, University Medical Centre Utrecht, The Netherlands. c.s.vankessel@umcutrecht.nl
authors.forename: C S
authors.initials: CS
authors.lastname: van Kessel
authors.forename: M S
authors.initials: MS
authors.lastname: van Leeuwen
authors.forename: M A A J
authors.initials: MA
authors.lastname: van den Bosch
authors.forename: I H M
authors.initials: IH
authors.lastname: Borel Rinkes
authors.forename: W P T M
authors.initials: WP
authors.lastname: Mali
authors.forename: P
authors.initials: P
authors.lastname: Westers
authors.forename: R
authors.initials: R
authors.lastname: van Hillegersberg
mesh_terms: D000368:Aged; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000473:pathology*; D003287:Contrast Media; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000556:secondary* / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D015588:Observer Variation; D011446:Prospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D003287:Contrast Media