title: Low accuracy of tumor markers for diagnosing pancreatic neuroendocrine tumors in multiple endocrine neoplasia type 1 patients.
abstract: BACKGROUND
  The assessment of tumor markers for diagnosing pancreatic neuroendocrine tumors (pNET) in multiple endocrine neoplasia type 1 (MEN1) patients is advised in the current guidelines but has never been validated for this purpose.
  
  
  OBJECTIVE
  The objective of the study was to assess the diagnostic accuracy of chromogranin A (CgA), pancreatic polypeptide (PP), and glucagon for pNET in MEN1.
  
  
  METHODS
  This was a diagnostic study.
  
  
  METHODS
  The study was conducted at Dutch university medical centers from 2008 to 2011, representing 90% of the total Dutch MEN1 population.
  
  
  METHODS
  Patients for whom data on tumor markers in combination with the reference standard (ie, radiological imaging) were available between 2008 and 2011 were included. The reference standard for the presence of pNET was pathology or detection on magnetic resonance imaging, computed tomography, or endoscopic ultrasound confirmed on subsequent imaging, irrespective of modality at follow-up.
  
  
  METHODS
  The area under the receiver-operating characteristic curve (AUC), positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio, sensitivity, and specificity were calculated for each marker.
  
  
  RESULTS
  For the analysis of PP, CgA, and glucagon, 73, 81, and 94 patients were available, respectively. The AUC for CgA was 0.48 [95% confidence interval (CI) 0.35-0.61] with a sensitivity 0.33 and a specificity 0.73; the AUC for glucagon was 0.58 (95% CI 0.46-0.70) with a sensitivity 0.43 and a specificity 0.73; and the AUC for PP was 0.64 (95% CI 0.50-0.77) with a sensitivity 0.36 and a specificity 0.74. Age, imaging modality, tumor size, and number did not influence the outcomes.
  
  
  CONCLUSIONS
  The diagnostic accuracy of the tumor markers CgA, PP, and glucagon for pNET in MEN1 is low.
authors: MD, PhD, Department of Internal Medicine, L00.408, University Medical Center Utrecht, PO Box 85500, 3508 GA Utrecht, The Netherlands. G.D.Valk@umcutrecht.nl.
authors: Joanne M
authors: JM
authors: de Laat
authors: Carolina R C
authors: CR
authors: Pieterman
authors: Maaike
authors: M
authors: Weijmans
authors: Ad R
authors: AR
authors: Hermus
authors: Olaf M
authors: OM
authors: Dekkers
authors: Wouter W
authors: WW
authors: de Herder
authors: Anouk N A
authors: AN
authors: van der Horst-Schrivers
authors: Madeleine L
authors: ML
authors: Drent
authors: Peter H
authors: PH
authors: Bisschop
authors: Bas
authors: B
authors: Havekes
authors: Menno R
authors: MR
authors: Vriens
authors: Gerlof D
authors: GD
authors: Valk
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D053379:Chromogranin A / Q000097:blood; D005260:Female; D005934:Glucagon / Q000097:blood; D006801:Humans; D008297:Male; D008875:Middle Aged; D018761:Multiple Endocrine Neoplasia Type 1 / Q000097:blood*; D018358:Neuroendocrine Tumors / Q000097:blood / Q000175:diagnosis*; D010190:Pancreatic Neoplasms / Q000097:blood / Q000175:diagnosis*; D010191:Pancreatic Polypeptide / Q000097:blood
chemical_list: D014408:Biomarkers, Tumor; D053379:Chromogranin A; D010191:Pancreatic Polypeptide; D005934:Glucagon