title: Clinical outcomes of whole pelvis radiotherapy and stereotactic body radiotherapy boost for intermediate- and high-risk prostate cancer.
abstract: OBJECTIVE
  We report our experience with Cyberknife to deliver hypofractionated stereotactic body radiotherapy (SBRT) boost combined with whole pelvis radiotherapy (WPRT) to patients with intermediate- to high-risk prostate cancer.
  
  
  METHODS
  From March 2008 to July 2014, 39 patients with newly diagnosed, intermediate- and high-risk (National Comprehensive Cancer Network definition) localized prostate cancer were treated with WPRT and SBRT boost. The whole pelvis dose was 45 Gy (25 fractions of 1.8 Gy) and the SBRT boost dose was 21 Gy (3 fractions of 7 Gy). No one received androgen deprivation therapy before biochemical relapse. The acute and late toxicities were recorded using the Radiation Therapy Oncology Group scale. Prostate-specific antigen (PSA) response was monitored.
  
  
  RESULTS
  Thirty-nine patients with a median 53.6 months (range 14-74 months) follow-up were analyzed. The median pretreatment PSA was 15.97 ng/mL. The estimated 5-year biochemical failure (BCF)-free survival was 94.7%. Two BCFs were observed in only high-risk group. The median PSA nadir was 0.30 ng/mL at median 36 months and PSA bounce occurred in 15.4% (n = 6) of patients at median 12 months. No grade 3 acute toxicity was noted. A total of 23% of the patients had grade 2 acute genitourinary (GU) toxicities and 21% had grade 2 acute gastrointestinal (GI) toxicities. At 2 months, most complications had returned to baseline. GU and GI toxicities were observed.
  
  
  CONCLUSIONS
  WPRT followed by SBRT boost using Cyberknife in intermediate- and high-risk prostate cancer is feasible with minimal toxicity and encouraging BCF-free survival.
authors: Department of Radiation Oncology, Inha University Hospital, Inha University of Medicine, Inchon, Korea.
authors: Hun Jung
authors: HJ
authors: Kim
authors: Department of Radiation Oncology, Inha University Hospital, Inha University of Medicine, Inchon, Korea.
authors: Jeong Hoon
authors: JH
authors: Phak
authors: Department of Radiation Oncology, Inha University Hospital, Inha University of Medicine, Inchon, Korea.
authors: Woo Chul
authors: WC
authors: Kim
mesh_terms: D000368:Aged; D006801:Humans; D008297:Male; D008875:Middle Aged; D010388:Pelvis / Q000473:pathology / Q000601:surgery*; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D016634:Radiosurgery / Q000379:methods*; D016896:Treatment Outcome
keywords: Cyberknife; PSA; prostate cancer; radiotherapy; stereotactic body radiotherapy