Hydrogel spacers in prostate radiotherapy: a promising approach to decrease rectal toxicity

Future Oncol. 2017 Dec;13(29):2697-2708. doi: 10.2217/fon-2017-0073. Epub 2017 Nov 23.


High-dose radiation is a well-established method of treatment for prostate cancer. The main limiting structure for dose escalation is the rectum. The risk of rectal toxicity is related to dose received by the rectum. Several strategies for reducing dose to rectum have been explored; these include endorectal balloons as well as injection of rectal spacers like hydrogels. They create greater distance between rectal wall and prostate to confer a dosimetric advantage to the rectum. Early clinical studies with hydrogels have shown favorable outcomes. A low incidence of major procedural adverse effects with hydrogel use has been reported and it is well tolerated by patients. Hydrogel holds promise in establishing itself as an adjunct to standard of care in prostate radiation.

Keywords: IMRT; dosimetry; hydrogel; proctitis; prostate; radiation; radiotherapy; rectum; spacer; toxicity.

MeSH terms

  • Biocompatible Materials* / chemistry
  • Cost-Benefit Analysis
  • Humans
  • Hydrogel, Polyethylene Glycol Dimethacrylate* / chemistry
  • Male
  • Polyethylene Glycols
  • Prostatic Neoplasms / diagnosis
  • Prostatic Neoplasms / radiotherapy*
  • Quality of Life
  • Radiation Dosage
  • Radiation Injuries / diagnosis
  • Radiation Injuries / prevention & control
  • Radiometry
  • Radiosurgery / adverse effects
  • Radiosurgery / methods
  • Radiotherapy Planning, Computer-Assisted
  • Radiotherapy, Intensity-Modulated* / adverse effects
  • Radiotherapy, Intensity-Modulated* / methods
  • Rectum / radiation effects*
  • Treatment Outcome


  • Biocompatible Materials
  • Hydrogel, Polyethylene Glycol Dimethacrylate
  • Polyethylene Glycols