title: Prognostic impact of definitive local therapy of the primary tumor in men with metastatic prostate cancer at diagnosis: A population-based, propensity score analysis.
abstract: BACKGROUND
  This study investigated whether definitive local therapy [radical prostatectomy (RP) or brachytherapy (BT)] of the primary tumor improves survival in men with metastatic prostate cancer (PrCA) at diagnosis.
  
  
  METHODS
  Data on newly diagnosed metastatic PrCA cases (stage IV, N=7858) were obtained from the Surveillance Epidemiology and End Results (SEER) program. Conventional multivariable survival analysis and propensity score analysis were used to estimate hazard ratios (HRs) and corresponding 95% confidence intervals (95% CI) comparing men who underwent definitive local therapy of the primary tumor to those who did not.
  
  
  RESULTS
  After adjusting for sociodemographic and tumor attributes, having RP after diagnosis with metastatic PrCA was associated with 73% (HR=0.27, 95% CI: 0.20-0.38) lower risk of all-cause mortality and 72% (HR=0.28, 95% CI: 0.20-0.39) reduced risk of death from PrCA. Having BT also was associated with 57% (HR=0.43, 95% CI: 0.31-0.59) and 54% (HR=0.46, 95% CI: 0.33-0.64) lower risk of all-cause and PrCA-specific mortality. Similar results were observed in propensity score-adjusted analysis as well as when stratified by age and extent of tumor metastasis.
  
  
  CONCLUSIONS
  These findings suggest that definitive local therapy improves survival in men with metastatic PrCA at diagnosis. Future work should consider comorbidities, diet, physical activity and smoking status.
authors.affiliation: Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, Discovery I, 915 Greene Street, Suite 200, Columbia, SC 29208, United States. Electronic address: ANTWI@sc.edu.
authors.forename: Samuel
authors.initials: S
authors.lastname: Antwi
authors.affiliation: Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, Discovery I, 915 Greene Street, Suite 400, Columbia, SC 29208, United States. Electronic address: Everson@sc.edu.
authors.forename: Todd M
authors.initials: TM
authors.lastname: Everson
mesh_terms: D000230:Adenocarcinoma / Q000401:mortality / Q000556:secondary / Q000628:therapy*; D000328:Adult; D000368:Aged; D001918:Brachytherapy; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D057216:Propensity Score; D016016:Proportional Hazards Models; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000401:mortality / Q000473:pathology* / Q000628:therapy*; D012189:Retrospective Studies; D018426:SEER Program
keywords: Definitive therapy; Metastasis; Prostate cancer; SEER data; Stage IV prostate cancer; Survival