title: Whole Pelvis Versus Prostate-Only Radiotherapy With or Without Short-Course Androgen Deprivation Therapy and Mortality Risk.
abstract: BACKGROUND
  The purpose of the study was to determine whether the extent of prostate radiotherapy (ie, whole-pelvic radiotherapy [WPRT] vs. prostate and seminal vesicle radiotherapy [PSVRT]) is associated with all-cause mortality (ACM) in men treated with or without androgen deprivation therapy (ADT).
  
  
  METHODS
  A multiple-institution cohort of 3709 prostate cancer patients was prospectively assembled from 1991 to 2006. The median age was 72 years and all patients had T1c-T3N0M0 adenocarcinoma of the prostate. Patients were treated with WPRT or PSVRT followed by a brachytherapy boost, with or without neoadjuvant ADT (median duration, 4.2 months). Seventy percent of patients had unfavorable-risk disease (Gleason score ≥ 7; prostate-specific antigen ≥ 10 ng/mL; or stage ≥ T2b). Cox regression was applied to determine whether the radiation treatment volume affected the risk of ACM. The interaction between radiation volume and ADT use was assessed.
  
  
  RESULTS
  After a median follow-up of 3.3 years, 561 deaths were observed. A decreased risk of ACM was noted with the use of WPRT versus PSVRT (adjusted hazard ratio [AHR], 0.58; 95% confidence interval [CI], 0.38-0.89; P = .01), or with ADT use (AHR, 0.71; 95% CI, 0.58-0.90; P = .004). However, a combination of WPRT and ADT did not further improve ACM compared with either WPRT alone or PSVRT with ADT. Moreover, there was a significant interaction between the radiotherapeutic treatment volume and ADT (AHR, 1.61; 95% CI, 1.004-2.58; P = .048).
  
  
  CONCLUSIONS
  Treatment with WPRT or short-course ADT is associated with a decreased risk of ACM, although a combination of the two does not yield greater benefit. This observation suggests a shared mechanism for this risk reduction, which we hypothesize to be via the treatment of micrometastatic disease within the pelvic lymph nodes.
authors.affiliation: Harvard Radiation Oncology Program, Boston, MA. Electronic address: LBRAUNSTEIN@partners.org.
authors.forename: Lior Z
authors.initials: LZ
authors.lastname: Braunstein
authors.affiliation: Department of Statistics, University of Connecticut, Storrs, CT.
authors.forename: Ming-Hui
authors.initials: MH
authors.lastname: Chen
authors.affiliation: 21st Century Oncology, Fort Myers, FL.
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Dosoretz
authors.affiliation: 21st Century Oncology, Fort Myers, FL.
authors.forename: Sharon A
authors.initials: SA
authors.lastname: Salenius
authors.affiliation: 21st Century Oncology, Fort Myers, FL.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Katin
authors.affiliation: UF Health Cancer Center, Orlando, FL.
authors.forename: Akash
authors.initials: A
authors.lastname: Nanda
authors.affiliation: Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Boston, MA.
authors.forename: Anthony V
authors.initials: AV
authors.lastname: D'Amico
mesh_terms: D000368:Aged; D000726:Androgen Antagonists / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D060787:Neoplasm Grading; D010388:Pelvis / Q000528:radiation effects; D011446:Prospective Studies; D011467:Prostate / Q000528:radiation effects; D011471:Prostatic Neoplasms / Q000401:mortality* / Q000473:pathology / Q000628:therapy*; D011878:Radiotherapy / Q000379:methods*; D012044:Regression Analysis; D016896:Treatment Outcome
chemical_list: D000726:Androgen Antagonists
keywords: Hormonal therapy; Lymph nodes; Nodal irradiation; Pelvic radiation; Prostate cancer; Radiation therapy