title: Use of a rectal spacer with low-dose-rate brachytherapy for treatment of prostate cancer in previously irradiated patients: Initial experience and short-term results.
abstract: BACKGROUND
  Salvage brachytherapy in patients with prior pelvic radiation carries a risk of rectal injury. Herein, we report our initial experience using a hydrogel spacer between the prostate and the rectum during salvage brachytherapy.
  
  
  METHODS
  A total of 11 patients with prostate cancer and prior radiotherapy (5 prostate brachytherapy, 2 prostate external beam radiation therapy [EBRT], and 4 rectal cancer EBRT) received (125)I brachytherapy after attempted placement of 10cc of a diluted hydrogel spacer between the prostate and rectum.
  
  
  RESULTS
  Spacing was achieved in 8 of the 11 (73%) patients but was not possible in 3 (1 prior brachytherapy and 2 prior EBRT) owing to fibrosis and adhesions. For the 8 patients in whom spacing was accomplished, the median space between the prostate and rectum was 10.9mm (prior EBRT) vs. 7.7mm (prior brachytherapy), p=0.048. Median followup was 15.7 months. One patient developed a prostato-rectal fistula requiring a diverting colostomy. The 16-month estimate of late Grade 3 or 4 gastrointestinal or genitourinary toxicity was 26%. One patient developed lymph node-positive recurrence. The 16-month prostate-specific antigen failure-free survival rate was 89%. Compared with baseline, Expanded Prostate Cancer Index Composite for Clinical Practice urinary quality of life (QoL) was significantly worse at 3 and 6 months but not significantly worse by 1 year. There were no significant changes throughout the study period in bowel or sexual QoL.
  
  
  CONCLUSIONS
  Hydrogel spacer placements may be feasible in most patients with prior pelvic radiation. Further followup is needed to determine whether spacer placement will produce long-term improvements in toxicity or QoL.
authors.affiliation: Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Brandon A
authors.initials: BA
authors.lastname: Mahal
authors.affiliation: Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: David R
authors.initials: DR
authors.lastname: Ziehr
authors.affiliation: Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Hyatt
authors.affiliation: Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Emily H
authors.initials: EH
authors.lastname: Neubauer-Sugar
authors.affiliation: Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Desmond A
authors.initials: DA
authors.lastname: O'Farrell
authors.affiliation: Division of Urology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Michael P
authors.initials: MP
authors.lastname: O'Leary
authors.affiliation: Division of Urology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Graeme S
authors.initials: GS
authors.lastname: Steele
authors.affiliation: Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Niedermayr
authors.affiliation: Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Clair J
authors.initials: CJ
authors.lastname: Beard
authors.affiliation: Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Neil E
authors.initials: NE
authors.lastname: Martin
authors.affiliation: Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Peter F
authors.initials: PF
authors.lastname: Orio
authors.affiliation: Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Anthony V
authors.initials: AV
authors.lastname: D'Amico
authors.affiliation: Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Phillip M
authors.initials: PM
authors.lastname: Devlin
authors.affiliation: Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA. Electronic address: pnguyen@LROC.harvard.edu.
authors.forename: Paul L
authors.initials: PL
authors.lastname: Nguyen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000009:adverse effects / Q000379:methods*; D005240:Feasibility Studies; D005500:Follow-Up Studies; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000532:radiotherapy*; D058958:Organs at Risk / Q000528:radiation effects*; D011471:Prostatic Neoplasms / Q000401:mortality / Q000532:radiotherapy*; D011788:Quality of Life; D011879:Radiotherapy Dosage; D012007:Rectum / Q000528:radiation effects*; D016879:Salvage Therapy / Q000009:adverse effects / Q000379:methods*; D016019:Survival Analysis; D016896:Treatment Outcome
chemical_list: D020136:Hydrogel, Polyethylene Glycol Dimethacrylate
keywords: Brachytherapy; Hydrogel spacer; Prior pelvic irradiation; Prior pelvic radiation; Prostate cancer; Rectal spacer; Salvage