title: Correlation between low Gleason score and prostate specific antigen levels with incidence of bone metastases in prostate cancer patients: when to omit bone scans?
abstract: BACKGROUND
  To identify correlation and incidence of bone metastases in prostate cancer patient with low Gleason scores (GS) and prostate specific antigen (PSA) levels.
  
  
  METHODS
  This descriptive restrospective study covered patients with prostate cancer in Cipto Mangunkusumo Hospital in 2006-2011. Of a total of 478, those who had PSA values, histological examination, and bone scan were included, resulting in 358 eligible cases. PSA values were measured using the sandwich electrochemiluminescent immunoassay. Histological examination was graded according to Gleason's grading system and divided into 3 categories: well differentiated (GS ≤ 6), moderately differentiated (GS 7) and poorly differentiated (GS 8-10). Bone scans were performed using a radiopharmaceutical agent (Tc 99m methylenen diphosphonate) with images captured by gamma camera.
  
  
  RESULTS
  The mean age was 67.5 ± 7.8, mean GS was 7.7 ± 1.3 and median PSA was 56.9 (range: 0.48-17000 ng/ mL). There were 11 patients (3.0%) with positive bone scan with PSA<20 ng/mL and GS<8. Furthermore, there were 2 patients (0.6%) with GS ≤ 6 and PSA<10 ng/mL showing bone metastasis.
  
  
  CONCLUSIONS
  In our study, there were still small percentage of patients with bone metastasis even when low values of PSA (PSA<10 ng/mL) and GS (GS ≤ 6) were applied.
authors.affiliation: Department of Urology, Cipto Mangunkusumo Hospital, University of Indonesia, Jakarta, Indonesia E-mail : rainy.umbas@gmail.com.
authors.forename: I Putu Gde
authors.initials: IP
authors.lastname: Sanjaya
authors.forename: Chaidir Arief
authors.initials: CA
authors.lastname: Mochtar
authors.forename: Rainy
authors.initials: R
authors.lastname: Umbas
mesh_terms: D000368:Aged; D001859:Bone Neoplasms / Q000097:blood / Q000000981:diagnostic imaging / Q000556:secondary*; D001842:Bone and Bones / Q000000981:diagnostic imaging*; D015331:Cohort Studies; D004164:Diphosphonates; D006801:Humans; D007214:Indonesia; D007610:Kallikreins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D018579:Patient Selection; D011467:Prostate / Q000473:pathology*; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood / Q000473:pathology*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D017556:Technetium Compounds
chemical_list: D004164:Diphosphonates; D019275:Radiopharmaceuticals; D017556:Technetium Compounds; C029045:technetium Tc 99m diphosphonate; C549870:KLK3 protein, human; D007610:Kallikreins; D017430:Prostate-Specific Antigen