title: Is visual radiological evaluation of liver tumour burden in patients with neuroendocrine tumours reproducible?
abstract: BACKGROUND
  Visual semi-quantitative assessment of liver tumour burden for neuroendocrine tumour liver metastases is often used in patient management and outcome. However, published data on the reproducibility of these evaluations are lacking.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the interobserver and intraobserver agreement of a visual semi-quantitative assessment of liver tumour burden using CT scan.
  
  
  METHODS
  Fifty consecutive patients (24 men and 26 women, mean aged 54 years) were retrospectively reviewed by four readers (two senior radiologists, one junior radiologist and one gastroenterologist) who assessed the liver tumour burden based on a visual semi-quantitative method with four classes (0-10, 11-25, 26-50 and ≥50%). Interobserver and intraobserver agreement were assessed by weighted kappa coefficient and percentage of agreement. The intraclass correlation was calculated.
  
  
  RESULTS
  Agreement among the four observers for the evaluation of liver tumour burden was substantial, ranging from 0.62 to 0.73 (P < 0.0001). The intraclass coefficient was 0.977 (P < 0.0001). Intraobserver agreement was 0.78 and ICC was 0.97.
  
  
  CONCLUSIONS
  Reproducibility of the visual semi-quantitative evaluation of liver tumour burden is good and is independent of the level of experience of the readers. We therefore suggest that clinical studies in patients with neuroendocrine liver metastases use this method to categorise liver tumour burden.
authors.affiliation: Univ Paris DiderotSorbonne Paris Cité, Paris, France magaly.zappa@aphp.fr.|INSERMUMR1149 CRI, Paris, France.|Department of RadiologyAP-HP, Clichy, France.
authors.forename: Magaly
authors.initials: M
authors.lastname: Zappa
authors.affiliation: Department of Gastroenterology and PancreatologyAP-HP, Clichy, France.
authors.forename: Olivia
authors.initials: O
authors.lastname: Hentic
authors.affiliation: Department of RadiologyAP-HP, Clichy, France.
authors.forename: Marie-Pierre
authors.initials: MP
authors.lastname: Vullierme
authors.affiliation: Department of RadiologyAP-HP, Clichy, France.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Lagadec
authors.affiliation: Univ Paris DiderotSorbonne Paris Cité, Paris, France.|INSERMUMR1149 CRI, Paris, France.|Department of RadiologyAP-HP, Clichy, France.
authors.forename: Maxime
authors.initials: M
authors.lastname: Ronot
authors.affiliation: Univ Paris DiderotSorbonne Paris Cité, Paris, France.|INSERMUMR1149 CRI, Paris, France.|Department of Gastroenterology and PancreatologyAP-HP, Clichy, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Ruszniewski
authors.affiliation: Univ Paris DiderotSorbonne Paris Cité, Paris, France.|INSERMUMR1149 CRI, Paris, France.|Department of RadiologyAP-HP, Clichy, France.
authors.forename: Valérie
authors.initials: V
authors.lastname: Vilgrain
keywords: CT scan; liver burden; liver metastases; neuroendocrine tumour