title: Predictors of Positive Bone Metastasis in Newly Diagnosed Prostate Cancer Patients.
abstract: BACKGROUND
  The prevalence of prostate cancer (PCa) has been increasing in recent years. Treatment strategies are largely based on the results of bone scan screening. Therefore, our aim was to investigate predictors of positive bone metastasis in newly diagnosed PCa patients.
  
  
  METHODS
  After extensive review, 336 consecutive patients newly diagnosed with PCa between April 2010 and November 2013 at our institution were enlisted in the study. Patients were divided into two groups according to bone scan results. Univariate analyses (Chi-square test for discrete variables and independent t-test for continuous variables) were applied to determine the potentially significant risk factors associated with distant bone metastasis. Binary logistic regression analyses were used to further investigate the influence of these factors on bone metastasis.
  
  
  RESULTS
  The patient mean age was 71.9 ± 8.6 years (range: 48 to 94 years). The mean prostate specific antigen (PSA) level and biopsy Gleason score were 260.2 ± 1107.8 ng/mL and 7.4 ± 1.5, respectively. The body mass index (BMI) for the series was 24.5 ± 3.4 kg/m2. Sixty-four patients (19.0%) had a positive bone scan result. Patients with positive bone scan results had a significantly lower BMI (23.3 ± 3.5 vs. 24.8 ± 3.3; p=0.003), a higher Gleason score (8.5 ± 1.1 vs. 7.1 ± 1.5; p < 0.001), and a higher PSA level (1071.3 ± 2337.1 vs. 69.4 ± 235.5; p < 0.001) than those without bone metastasis. Multivariate logistic regression analysis employing the above independent predictors demonstrated that a Gleason score of ≥7, clinical stage ≥T3, BMI ≤22 kg/m2, and an initial PSA level of ≥20 ng/mL were all independent predictors of bone metastasis.
  
  
  CONCLUSIONS
  A bone scan might be necessary in newly diagnosed PCa patients with any of the following criteria: clinical stage T3 or higher, a Gleason score of 7 or higher, BMI equal to or less than 22, and a PSA level of 20 or higher.
authors.affiliation: Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan E-mail : shpihu@yahoo.com.tw.
authors.forename: Tsu-Ming
authors.initials: TM
authors.lastname: Chien
authors.forename: Yen-Man
authors.initials: YM
authors.lastname: Lu
authors.forename: Jiun-Hung
authors.initials: JH
authors.lastname: Geng
authors.forename: Tsung-Yi
authors.initials: TY
authors.lastname: Huang
authors.forename: Hung-Lung
authors.initials: HL
authors.lastname: Ke
authors.forename: Chun-Nung
authors.initials: CN
authors.lastname: Huang
authors.forename: Ching-Chia
authors.initials: CC
authors.lastname: Li
authors.forename: Yii-Her
authors.initials: YH
authors.lastname: Chou
authors.forename: Wen-Jeng
authors.initials: WJ
authors.lastname: Wu
authors.forename: Shu-Pin
authors.initials: SP
authors.lastname: Huang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary* / Q000601:surgery; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D011237:Predictive Value of Tests; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics*; D012307:Risk Factors; D015996:Survival Rate; D013669:Technetium Tc 99m Medronate / Q000493:pharmacokinetics*; D014018:Tissue Distribution
chemical_list: D019275:Radiopharmaceuticals; D013669:Technetium Tc 99m Medronate