title: Stereotactic body radiation therapy for low and intermediate risk prostate cancer-Results from a multi-institutional clinical trial.
abstract: We report the outcome of a phase I/II clinical trial of stereotactic body radiation therapy (SBRT) for low (LR) and select intermediate risk (IR) prostate cancer (PCa) patients.
  
  
  
  Eligible patients included men with prostate adenocarcinoma with Gleason score 6 with PSA ≤ 20 or Gleason 7 with PSA ≤ 15 and clinical stage ≤ T2b. For the phase I portion of the study patients in cohorts of 15 received 45, 47.5, or 50 Gray (Gy) in five fractions. Since the maximally tolerated dose was not met in the phase I study, an additional 47 patients received 50 Gy in five fractions in the phase II study. Toxicity using Common Toxicity Criteria for Adverse Events v. 3.0, quality of life, and outcome data was collected.
  
  
  
  A total of 91 patients are included for analysis; 63.7% had NCCN IR and 36.3% had LR PCa. At a median follow up of 54 months the actuarial freedom from biochemical failure was 100% at 3 years and 98.6% at 5 years. Actuarial distant metastasis free survival was 100% at 3 and 5 years. Overall survival was 94% at 3 years and 89.7% at 5 years with no deaths attributed to PCa. Acute and late urinary grade ≥ III toxicity occurred in 0% and 5.5% of patients, respectively. Gastrointestinal (GI) acute and late toxicity of grade ≥ III occurred in 2% and 7% of patients, respectively. A total of four men experienced grade IV toxicity (three GI, one genitourinary).
  
  
  
  SBRT treatment results in excellent biochemical control rates at 5 years for LR and IR PCa patients although doses greater than 47.5 Gy in five fractions led to increased severe late toxicity.
authors.affiliation: Department of Radiation Oncology, University of Texas Southwestern Medical Center, USA.
authors.forename: Raquibul
authors.initials: R
authors.lastname: Hannan
authors.affiliation: Department of Radiation Oncology, University of Texas Southwestern Medical Center, USA.
authors.forename: Vasu
authors.initials: V
authors.lastname: Tumati
authors.affiliation: Department of Clinical Sciences, University of Texas Southwestern Medical Center, USA.
authors.forename: Xian-Jin
authors.initials: XJ
authors.lastname: Xie
authors.affiliation: Department of Radiation Oncology, University of Minnesota, USA.
authors.forename: L Chinsoo
authors.initials: LC
authors.lastname: Cho
authors.affiliation: Department of Radiation Oncology, University of Colorado, USA.
authors.forename: Brian D
authors.initials: BD
authors.lastname: Kavanagh
authors.affiliation: Department of Radiation Oncology, Prairie Lakes Hospital, USA.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Brindle
authors.affiliation: Department of Radiation Oncology, University of Colorado, USA.
authors.forename: David
authors.initials: D
authors.lastname: Raben
authors.affiliation: Department of Radiation Oncology, Orlando Health, USA.
authors.forename: Akash
authors.initials: A
authors.lastname: Nanda
authors.affiliation: Department of Radiation Oncology, University of Texas Southwestern Medical Center, USA.
authors.forename: Susan
authors.initials: S
authors.lastname: Cooley
authors.affiliation: Texas Oncology-Waco, USA.
authors.forename: D W Nathan
authors.initials: DWN
authors.lastname: Kim
authors.affiliation: Radiation Research Program, NCI, USA.
authors.forename: David
authors.initials: D
authors.lastname: Pistenmaa
authors.affiliation: Department of Urology, University of Texas Southwestern Medical Center, USA.
authors.forename: Yair
authors.initials: Y
authors.lastname: Lotan
authors.affiliation: Department of Radiation Oncology, University of Texas Southwestern Medical Center, USA. Electronic address: Robert.Timmerman@utsouthwestern.edu.
authors.forename: Robert
authors.initials: R
authors.lastname: Timmerman
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D060787:Neoplasm Grading; D017430:Prostate-Specific Antigen / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D011788:Quality of Life; D016634:Radiosurgery / Q000009:adverse effects / Q000379:methods* / Q000401:mortality; D011879:Radiotherapy Dosage; D016896:Treatment Outcome
chemical_list: D017430:Prostate-Specific Antigen
keywords: Dose constraints; Prostate cancer; SBRT; Stereotactic body radiation therapy