title: Serum Levels of NTx and TRACP5b in Giant Cell Tumor of Bone and its Clinical Implications.
abstract: BACKGROUND
  To investigate the serum levels of N-terminal telopeptide of type I collagen (NTx) and tartrate-resistant acid phosphatase 5b (TRACP5b) in giant cell tumor of bone (GCT) patients and the clinical implications.
  
  
  METHODS
  56 GCT patients (29 males and 27 females, 15 to 60 years old with a median age of 28.0 years old) with clinicopathological characteristics of GCT were enrolled in the Department of Bone Cancer, the Affiliated Cancer Hospital of Xinjiang Medical University from October 2008 to October 2014. The enzyme-linked immunosorbent assay (ELISA) was used to detect the serum levels of NTx and TRACP5b in the patients.
  
  
  RESULTS
  Compared with 21 patients who had a GCT of < 5 cm, the serum levels of NTx and TRACP5b in the 35 patients with a GCT of ≥ 5 cm were significantly increased (p < 0.05). Compared with those GCT patients who had a grade I tumor, the levels of NTx and TRACP5b in grade II patients were not increased (p > 0.05), but the levels of NTx and TRACP5b were significantly increased in grade III patients (p < 0.05). Moreover, compared with the patients in histologic stage I, the levels of NTx and TRACP5b in stage II GCT patients were not increased (p > 0.05), whereas the levels in grade III patients were significantly increased (p < 0.05). In addition, the location of the tumor had a significant effect on the serum levels of NTx and TRACP5b (p < 0.05).
  
  
  CONCLUSIONS
  Our study suggests that serum NTx and TRACP5b are sensitive and simple biomarkers to indicate aberrant bone metabolism in GCT patients, and they may have a clinical significance in GCT diagnosis. Combined examination for both markers helps in the classification of clinicopathological stages of GCT patients and in the prognosis of the disease.
authors.forename: Jiangtao
authors.initials: J
authors.lastname: Chen
authors.forename: Aikebaier
authors.initials: A
authors.lastname: Younusi
authors.forename: Li
authors.initials: L
authors.lastname: Cao
authors.forename: Leilei
authors.initials: L
authors.lastname: Xu
authors.forename: Yijun
authors.initials: Y
authors.lastname: Zhou
authors.forename: Tian
authors.initials: T
authors.lastname: Zhen
authors.forename: Xinghua
authors.initials: X
authors.lastname: Song
mesh_terms: D000135:Acid Phosphatase / Q000097:blood*; D000293:Adolescent; D000328:Adult; D014408:Biomarkers, Tumor / Q000097:blood*; D001859:Bone Neoplasms / Q000097:blood* / Q000473:pathology; D024042:Collagen Type I / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D018212:Giant Cell Tumor of Bone / Q000097:blood* / Q000473:pathology; D006801:Humans; D007527:Isoenzymes / Q000097:blood*; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D010455:Peptides / Q000097:blood*; D011237:Predictive Value of Tests; D000071681:Tartrate-Resistant Acid Phosphatase; D014057:Tomography, X-Ray Computed; D047368:Tumor Burden; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D024042:Collagen Type I; D007527:Isoenzymes; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase