title: Predictors of bone metastasis in pre-treatment staging of asymptomatic treatment-naïve patients with prostate cancer.
abstract: BACKGROUND
  There is no general consensus on the optimal criteria for the application of bone scintigraphy in screening of bone metastasis in patients with prostate cancer. Our study was conducted to assess the value of bone scan for pre-treatment staging of asymptomatic treatment-naïve patients with prostate cancer.
  
  
  METHODS
  A total of 203 consecutive asymptomatic and treatment-naïve patients with prostate cancer (age: 67.6±6.4 years) who were referred to our department for whole body bone scintigraphy were enrolled in the study. Three hours after intravenous injection of 20mCi (99m)Tc-MDP, all patients underwent whole body bone scanning using a single head gamma camera. The planar images were supplemented with SPECT as needed for questionable abnormalities or those having uncertain location on planar images.
  
  
  RESULTS
  The mean serum PSA levels, serum alkaline phosphatase (ALP) and Gleason score (GS) were 42.41±37.1ng/ml, 223.9±129.9IU/L and 6.7±1.1, respectively. A total of 55 cases (27.1%) out of 203 patients had bone metastases. The univariate analysis showed that serum PSA levels, GS and ALP were all significant predictors of bone metastases. However, only serum PSA and ALP levels were found to be independent predictors of bone metastasis in the multivariate logistic regression analysis. The combination of PSA and ALP (in which patients with either elevated PSA [>20ng/ml] or elevated ALP were considered as positive) had the best screening value, with 98.2% sensitivity and 48.6% specificity.
  
  
  CONCLUSIONS
  Serum ALP screening can be employed as a tool to detect the subgroup of patients who are at high risk of bone metastases, while having a PSA of <20ng/ml. The combination of PSA and ALP can be used to improve predictability of bone metastasis in newly diagnosed patients with prostate cancer, without affecting staging accuracy.
authors.affiliation: Department of Medical Physics and Biomedical Engineering, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: M
authors.initials: M
authors.lastname: Moslehi
authors.forename: M
authors.initials: M
authors.lastname: Cheki
authors.forename: M
authors.initials: M
authors.lastname: Salehi-Marzijarani
authors.forename: T
authors.initials: T
authors.lastname: Amuchastegui
authors.forename: A
authors.initials: A
authors.lastname: Gholamrezanezhad
mesh_terms: D000230:Adenocarcinoma / Q000097:blood / Q000000981:diagnostic imaging / Q000556:secondary*; D000368:Aged; D000469:Alkaline Phosphatase / Q000097:blood; D058070:Asymptomatic Diseases; D014408:Biomarkers, Tumor / Q000097:blood; D001859:Bone Neoplasms / Q000097:blood / Q000000981:diagnostic imaging / Q000556:secondary*; D055088:Early Detection of Cancer; D006801:Humans; D016015:Logistic Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D060787:Neoplasm Grading; D009363:Neoplasm Proteins / Q000097:blood; D009367:Neoplasm Staging / Q000379:methods*; D011237:Predictive Value of Tests; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000000981:diagnostic imaging / Q000473:pathology*; D019275:Radiopharmaceuticals; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013669:Technetium Tc 99m Medronate; D015899:Tomography, Emission-Computed, Single-Photon; D051598:Whole Body Imaging
chemical_list: D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; D019275:Radiopharmaceuticals; D000469:Alkaline Phosphatase; D017430:Prostate-Specific Antigen; D013669:Technetium Tc 99m Medronate
keywords: Asintomático; Asymptomatic; Bone scintigraphy; Cáncer de próstata; Diagnostic value; Gammagrafía ósea; Prostate cancer; Valor diagnóstico