title: The clinical value of von Willebrand factor in colorectal carcinomas.
abstract: BACKGROUND
  To identify the value of von Willebrand factor (vWF) as a clinical marker in colorectal carcinoma (CRC).
  
  
  METHODS
  Plasma levels of vWF were measured in 79 patients with UICC Stage I-IV CRC at time of operation and correlated with TNM categories, levels of the carcinoembryonic antigen (CEA), blood groups (BG) and 19 controls (CO). CO included cancer-free patients without bacterial or viral infections. For tissue analysis paraffin embedded tumour and mucosa sections of operation specimens were stained immunohistochemically for vWF and compared to vWF plasma levels as well as to TNM categories.
  
  
  RESULTS
  VWF plasma levels in CRC patients were significantly dependent on blood groups (p=0.012) and elevated compared to the normal ranges as well as to controls (BG 0: p=0.668, BG A/AB/B: p=0.020). CRC-Patients over 60 years of age presented with significantly higher vWF levels than patients below 60 years (BG 0: p=0.005; BG A/AB/B: p=0.035). There was no correlation of vWF plasma levels and UICC stages in CRC. Patients with elevated vWF plasma levels also presented with elevated CEA levels, but significance was missing (p=0.080). VWF concentration within the tumour tissue was independent of concentration within normal mucosa, blood groups, histopathological characteristics and did not correlate with plasma vWF levels.
  
  
  CONCLUSIONS
  VWF plasma levels are elevated in CRC patients, but not in a stage dependent manner. Besides the tumour at least blood groups and age mainly influence plasma vWF levels. In our opinion vWF as a routinely used clinical marker in CRC cannot be recommended.
authors: Vera S
authors: VS
authors: Schellerer
authors: Larissa
authors: L
authors: Mueller-Bergh
authors: Susanne
authors: S
authors: Merkel
authors: Robert
authors: R
authors: Zimmermann
authors: Dominik
authors: D
authors: Weiss
authors: Anne
authors: A
authors: Schlabrakowski
authors: Elisabeth
authors: E
authors: Naschberger
authors: Michael
authors: M
authors: Stürzl
authors: Werner
authors: W
authors: Hohenberger
authors: Roland S
authors: RS
authors: Croner