title: Serum chromogranin-A in advanced prostate cancer.
abstract: OBJECTIVE
  To determine the value of serum chromogranin A (CgA), a marker of neuroendocrine differentiation, for monitoring prostate cancer: CgA levels were related to three other tumour markers, i.e. total prostate-specific antigen (tPSA), prostatic acid phosphatase (PAP), neurone-specific enolase (NSE), and to testosterone, to assess the importance of hormone withdrawal.
  
  
  METHODS
  Serum samples (218) were obtained from 118 patients with prostate cancer, including 111 patients with advanced prostate cancer: 103 presented to our centre for systemic radionuclide therapy of painful skeletal metastases. CgA concentrations were measured using a new immunoradiometric assay (IRMA: Cis Bio International, Gif sur Yvette, France) and a threshold of 70 ng/mL was determined after receiver operating characteristic curve analysis. Testosterone was also measured with an IRMA assay; tPSA, PAP and NSE were assayed using the time-resolved amplified cryptate emission.
  
  
  RESULTS
  Serum marker levels were high in 64% of the patients for CgA, 24% for NSE, 89% for tPSA and 81% for PAP. Patients resistant to endocrine treatments and with elevated tPSA (i.e. hormone-independent) showed increased CgA and NSE in 62% and 29%, respectively. Patients with hormone-dependent prostate cancer (i.e. with a normal tPSA level) had elevated CgA in 59% but no abnormal NSE. All patients of the latter group except one showed clinical progression of their disease. However, the mean (SD) concentrations of CgA in hormone-independent (146) or hormone-dependent (22) patients, at 185.3 (449.1) and 160.9 (293.9) ng/mL, respectively, were not statistically different (P=0.8, Mann-Whitney U-test). For 30 patients, blood samples were drawn and markers measured before and after systemic radionuclide therapy. There was a significant increase in the CgA and tPSA concentrations after treatment (P=0.0146 and 0.0025, respectively).
  
  
  CONCLUSIONS
  In association with tPSA, serum CgA appears to be a promising marker for monitoring patients with prostate cancer.
authors.affiliation: Service de Médecine Nucléaire, Centre René Huguenin, Saint-Cloud, France. m.ferrero-pous@stcloud-huguenin.org
authors.forename: M
authors.initials: M
authors.lastname: Ferrero-Poüs
authors.forename: A M
authors.initials: AM
authors.lastname: Hersant
authors.forename: A
authors.initials: A
authors.lastname: Pecking
authors.forename: M
authors.initials: M
authors.lastname: Brésard-Leroy
authors.forename: M F
authors.initials: MF
authors.lastname: Pichon
mesh_terms: D000135:Acid Phosphatase; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use; D053379:Chromogranin A; D002864:Chromogranins / Q000097:blood*; D019008:Drug Resistance, Neoplasm; D006801:Humans; D008297:Male; D010751:Phosphopyruvate Hydratase / Q000097:blood; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000175:diagnosis*; D017027:Protein Tyrosine Phosphatases / Q000097:blood; D012372:ROC Curve; D012680:Sensitivity and Specificity; D013739:Testosterone / Q000097:blood
chemical_list: D018931:Antineoplastic Agents, Hormonal; C506150:CHGA protein, human; D053379:Chromogranin A; D002864:Chromogranins; D013739:Testosterone; D000135:Acid Phosphatase; C428439:prostatic acid phosphatase; D017027:Protein Tyrosine Phosphatases; D017430:Prostate-Specific Antigen; D010751:Phosphopyruvate Hydratase