title: Value of procollagen type 1 amino-terminal propeptide in patients with renal cell carcinoma.
abstract: BACKGROUND
  The aim of the study was to investigate whether the bone turnover marker procollagen type 1 amino-terminal propeptide (P1NP) could be useful for the early detection of bone metastases in patients with renal cell carcinoma (RCC) and if chemotherapy influences P1NP concentrations in patients with bone metastases.
  
  
  METHODS
  Serum samples of 36 patients were analyzed using a specific immunoassay. The patients were divided into three groups: 24 patients without metastatic spread, 6 patients with untreated bone metastases and 6 patients who had received sorafenib.
  
  
  RESULTS
  The P1NP concentration was significantly higher (p< or =0.001) in the patients with bone metastases (median: 396.10 ng/ml) than in those without bone involvement (median: 35.53 ng/ml). The patients treated with sorafenib showed levels within the normal range (median: 28.96 ng/ml).
  
  
  CONCLUSIONS
  P1NP is a significant diagnostic marker for the development of bone metastases in patients with RCC and could help to evaluate the progress of chemotherapy.
authors.affiliation: Department of Laboratory Medicine-Internal Medicine, Hospital of the Johann Wolfgang Goethe University, Frankfurt am Main, Germany. martina.klepzig@gmx.de
authors.forename: M
authors.initials: M
authors.lastname: Klepzig
authors.forename: H
authors.initials: H
authors.lastname: Sauer-Eppel
authors.forename: D
authors.initials: D
authors.lastname: Jonas
authors.forename: G M
authors.initials: GM
authors.lastname: Oremek