title: A dosimetric study of polyethylene glycol hydrogel in 200 prostate cancer patients treated with high-dose rate brachytherapy±intensity modulated radiation therapy.
abstract: OBJECTIVE
  We sought to analyze the effect of polyethylene glycol (PEG) hydrogel on rectal doses in prostate cancer patients undergoing radiotherapy.
  
  
  METHODS
  Between July 2009 and April 2013, we treated 200 clinically localized prostate cancer patients with high-dose rate (HDR) brachytherapy±intensity modulated radiation therapy. Half of the patients received a transrectal ultrasound (TRUS)-guided transperineal injection of 10mL PEG hydrogel (DuraSeal™ Spinal Sealant System; Covidien, Mansfield, MA) in their anterior perirectal fat immediately prior to the first HDR brachytherapy treatment and 5mL PEG hydrogel prior to the second HDR brachytherapy treatment. Prostate, rectal, and bladder doses and prostate-rectal distances were calculated based upon treatment planning CT scans.
  
  
  RESULTS
  There was a success rate of 100% (100/100) with PEG hydrogel implantation. PEG hydrogel significantly increased the prostate-rectal separation (mean±SD, 12±4mm with gel vs. 4±2mm without gel, p<0.001) and significantly decreased the mean rectal D2 mL (47±9% with gel vs. 60±8% without gel, p<0.001). Gel decreased rectal doses regardless of body mass index (BMI).
  
  
  CONCLUSIONS
  PEG hydrogel temporarily displaced the rectum away from the prostate by an average of 12mm and led to a significant reduction in rectal radiation doses, regardless of BMI.
authors.affiliation: Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, USA.
authors.forename: Tobin J
authors.initials: TJ
authors.lastname: Strom
authors.affiliation: Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, USA.
authors.forename: Richard B
authors.initials: RB
authors.lastname: Wilder
authors.affiliation: Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, USA.
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Fernandez
authors.affiliation: Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, USA.
authors.forename: Eric A
authors.initials: EA
authors.lastname: Mellon
authors.affiliation: Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, USA.
authors.forename: Amarjit S
authors.initials: AS
authors.lastname: Saini
authors.affiliation: Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, USA.
authors.forename: Dylan C
authors.initials: DC
authors.lastname: Hunt
authors.affiliation: Department of Urology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, USA.
authors.forename: Julio M
authors.initials: JM
authors.lastname: Pow-Sang
authors.affiliation: Department of Urology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, USA.
authors.forename: Phillipe E
authors.initials: PE
authors.lastname: Spiess
authors.affiliation: Department of Urology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, USA.
authors.forename: Wade J
authors.initials: WJ
authors.lastname: Sexton
authors.affiliation: Department of Urology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, USA.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Poch
authors.affiliation: Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, USA. Electronic address: Matthew.Biagioli@moffitt.org.
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Biagioli
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000009:adverse effects / Q000379:methods*; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000008:administration & dosage*; D007267:Injections; D008297:Male; D008875:Middle Aged; D011092:Polyethylene Glycols / Q000008:administration & dosage*; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D011829:Radiation Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods; D012007:Rectum / Q000000981:diagnostic imaging / Q000187:drug effects / Q000528:radiation effects; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography; D001743:Urinary Bladder / Q000000981:diagnostic imaging / Q000187:drug effects / Q000528:radiation effects
chemical_list: D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D011092:Polyethylene Glycols
keywords: Gel; HDR; High-dose-rate; Prostate; Radiotherapy