title: A population-based study of progression to metastatic prostate cancer in Australia.
abstract: BACKGROUND
  We used population-based data from the New South Wales Central Cancer Registry (CCR) to describe the patterns of progression to metastatic disease in Australian men diagnosed with non-metastatic prostate cancer.
  
  
  METHODS
  Data for all non-metastatic prostate cancer cases diagnosed 1993-2002 and followed to the end of 2007 were analysed. The outcome was progression to metastatic disease, identified by metastatic episode notifications in the CCR or by prostate cancer death. Factors associated with metastatic disease progression were identified using Cox regression models.
  
  
  RESULTS
  Of the 32,643 men with non-metastatic prostate cancer at diagnosis 43.1% had localised disease, 5.1% had regional spread and 51.9% had unknown stage. After a median of 6.8 years of follow-up 6708 cases (20.6%) had developed distant metastases. The risk of developing metastatic disease was significantly higher for those with regional (adjusted HR=2.65, 95% CI: 2.40-2.93) or unknown initial stage (adjusted HR=1.70, 95% CI: 1.61-1.80), for older men (65-74 years: HR=1.43, 95% CI: 1.33-1.53; >74 years: HR=2.73, 95% CI: 2.55-2.93), and those living in inner regional (HR=1.11, 95% CI: 1.04-1.18) or rural areas (HR=1.24, 95% CI: 1.14-1.36) or more disadvantaged areas (middle tertile: HR=1.09, 95% CI: 1.02-1.16; most disadvantaged: HR=1.12, 95% CI: 1.04-1.19). The risk of developing metastatic disease decreased over calendar time (adjusted HR=0.98, 95% CI: 0.97-0.99 per year).
  
  
  CONCLUSIONS
  After a median follow-up of 6.8 years more than 1 in 5 men diagnosed with non-metastatic prostate cancer developed distant metastases. This estimate of the overall risk of developing metastatic disease in the population, and the geographical disparities identified, can inform the planning of required cancer services.
authors.affiliation: Cancer Research Division, Cancer Council New South Wales, Sydney, Australia; Sydney School of Public Health, University of Sydney, Sydney, Australia. Electronic address: qingweil@nswcc.org.au.
authors.forename: Qingwei
authors.initials: Q
authors.lastname: Luo
authors.affiliation: Cancer Research Division, Cancer Council New South Wales, Sydney, Australia; Sydney School of Public Health, University of Sydney, Sydney, Australia.
authors.forename: Xue Qin
authors.initials: XQ
authors.lastname: Yu
authors.affiliation: Cancer Research Division, Cancer Council New South Wales, Sydney, Australia; Griffith Health Institute, Griffith University, Gold Coast, Queensland, Australia.
authors.forename: David Paul
authors.initials: DP
authors.lastname: Smith
authors.affiliation: Cancer Research Division, Cancer Council New South Wales, Sydney, Australia; Sydney School of Public Health, University of Sydney, Sydney, Australia; School of Medicine and Public Health, University of Newcastle, Newcastle, Australia; School of Public Health and Community Medicine, University of New South Wales, Sydney, Australia.
authors.forename: Dianne Lesley
authors.initials: DL
authors.lastname: O'Connell
mesh_terms: D000368:Aged; D001315:Australia; D018450:Disease Progression; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D016016:Proportional Hazards Models; D011471:Prostatic Neoplasms / Q000473:pathology*
keywords: Cancer registry; Disease progression; Distant metastases; Geographical disparity; Geographical location; Population-based study; Prostate cancer; Socio-economic status; Stage at diagnosis