title: Venous thrombosis and procoagulant factors in high-risk neuroblastoma.
abstract: OBJECTIVE
  The mechanism of increased thrombin production has been investigated in children with high-risk neuroblastoma (NB), to detect any possible association between catheter- related venous thrombosis (VT) and prothrombotic factors.
  
  
  METHODS
  Consecutive children with high-risk NB were studied by color-doppler ultrasonography of the upper vein system and thrombophilia factors assessment. Plasma levels of Tissue Factor (TF), Vascular Endothelial Growth Factor (VEGF), Prothrombin Activation Fragment 1+2, and Thrombin-Antithrombin Complex were evaluated. Moreover, inherited thrombophilia factors (homocystein, antithrombin, protein C, protein S, factor V Leiden, activated protein C resistence, mutation H1299R and G1691A of factor V, mutation G20210A of prothrombin, mutation T677 and A1298C of methylenetetrahydrofolate reductase, and allele 4G of plasminogen activator inhibitor-1) were tested to exclude congenital disorders.
  
  
  RESULTS
  Six patients with mean age: 48.8 months---were studied. Five patients were affected by stage 4 NB and another one by stage 3 NB with Myc-N amplification. All children had a central venous line (mean duration: 8.5 mos). Four patients (67%) had asymptomatic catheter-related VT visualized by color-doppler ultrasonography. No patient had major inherited thrombophilia factors. The levels of plasma TF and plasma VEGF were found elevated in all patients. Mean value of TF (nv 20.3+/-6.6) was 82 pg/mL with a range of 39 to 131 pg/mL. Mean value of VEGF (nv 24.3 pg/mL) was 78.5 pg/mL with a range of 31 to 142 pg/mL.
  
  
  CONCLUSIONS
  The increased risk of catheter-related VT detected in our small series of high-risk NB patients, was associated with elevated levels of circulating TF and VEGF. Further studies are needed to evaluate if elevated levels of TF/VEGF are involved both in the hypercoagulable state and in advanced childhood cancer.
authors.affiliation: Department of Pediatrics, University Sapienza of Rome, Rome Italy. amaliasc@tiscalinet.it
authors.forename: Amalia
authors.initials: A
authors.lastname: Schiavetti
authors.forename: Micaela
authors.initials: M
authors.lastname: Foco
authors.forename: Damiano
authors.initials: D
authors.lastname: Chiriacó
authors.forename: Metello
authors.initials: M
authors.lastname: Iacobini
authors.forename: Giulia
authors.initials: G
authors.lastname: Varrasso
authors.forename: Annapaola
authors.initials: A
authors.lastname: Ingrosso
authors.forename: Laura
authors.initials: L
authors.lastname: Conti
mesh_terms: D000990:Antithrombin III; D002404:Catheterization / Q000009:adverse effects; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D009447:Neuroblastoma / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood; D010447:Peptide Hydrolases / Q000097:blood; D011516:Prothrombin; D013925:Thromboplastin / Q000032:analysis*; D042461:Vascular Endothelial Growth Factor A / Q000097:blood*; D020246:Venous Thrombosis / Q000209:etiology*
chemical_list: D010446:Peptide Fragments; D042461:Vascular Endothelial Growth Factor A; C046193:antithrombin III-protease complex; C045879:prothrombin fragment 1.2; D000990:Antithrombin III; D011516:Prothrombin; D013925:Thromboplastin; D010447:Peptide Hydrolases