title: Does Radiotherapy for the Primary Tumor Benefit Prostate Cancer Patients with Distant Metastasis at Initial Diagnosis?
abstract: OBJECTIVE
  Treatment of the primary tumor reportedly improves survival in several types of metastatic cancer. We herein evaluated the efficacy and toxicity of radiotherapy for the primary tumor in prostate cancer with metastasis.
  
  
  METHODS
  The study cohort included 140 men with metastatic prostate cancer at initial diagnosis. Metastatic sites were divided into 4 groups as follows: solitary bone, 2-4 bones, ≥5 bones, and visceral organs. Patient, tumor, and treatment characteristics, and clinical outcomes were compared between patients treated with (prostate radiotherapy [PRT] group) or without radiotherapy to the primary tumor.
  
  
  RESULTS
  Patients in PRT group presented with a statistically significantly younger age (p = .02), whereas other characteristics showed no significant difference. Overall survival (OS) and biochemical failure-free survival (BCFFS) were improved in PRT patients (3-year OS: 69% vs. 43%, p = 0.004; 3-year BCFFS: 52% vs. 16%, p = 0.002). Multivariate analysis identified PRT as a significant predictor of both OS (hazard ratio [HR] = 0.43, p = 0.015). None of the 38 PRT patients experienced severe (grade ≥3) genitourinary or gastrointestinal toxicity.
  
  
  CONCLUSIONS
  Our data suggest that radiotherapy to the primary tumor was associated with improved OS and BCFFS in metastatic prostate cancer. The results of this study warrant prospective controlled clinical trials of this approach in stage IV prostate cancer patients with limited extent of bone metastasis and good performance status.
authors.affiliation: Departments of Radiation Oncology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Yeona
authors.initials: Y
authors.lastname: Cho
authors.affiliation: Departments of Radiation Oncology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jee Suk
authors.initials: JS
authors.lastname: Chang
authors.affiliation: Department of Urology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Koon Ho
authors.initials: KH
authors.lastname: Rha
authors.affiliation: Department of Urology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Sung Joon
authors.initials: SJ
authors.lastname: Hong
authors.affiliation: Department of Urology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Young Deuk
authors.initials: YD
authors.lastname: Choi
authors.affiliation: Department of Urology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Won Sik
authors.initials: WS
authors.lastname: Ham
authors.affiliation: Departments of Radiation Oncology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jun Won
authors.initials: JW
authors.lastname: Kim
authors.affiliation: Departments of Radiation Oncology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jaeho
authors.initials: J
authors.lastname: Cho
mesh_terms: D000230:Adenocarcinoma / Q000532:radiotherapy / Q000556:secondary*; D000368:Aged; D000728:Androgens; D018931:Antineoplastic Agents, Hormonal / Q000009:adverse effects; D001859:Bone Neoplasms / Q000473:pathology / Q000556:secondary; D018572:Disease-Free Survival; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009376:Neoplasms, Hormone-Dependent / Q000473:pathology / Q000532:radiotherapy*; D058958:Organs at Risk; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D011878:Radiotherapy / Q000009:adverse effects; D012983:Soft Tissue Neoplasms / Q000473:pathology / Q000556:secondary; D016896:Treatment Outcome
chemical_list: D000728:Androgens; D018931:Antineoplastic Agents, Hormonal