Comprehensive review of the use of hydrogel spacers prior to radiation therapy for prostate cancer

Abstract

To provide a comprehensive narrative review of the published data on the impact of hydrogel spacers on rectal dosimetry and toxicity and to outline the practicalities of inserting hydrogel spacers. ResultsA growing body of evidence suggests that the administration of hydrogel spacers is safe and is associated with limited perioperative morbidity. The impact on rectal dosimetry has been clearly established and use of hydrogel spacers is associated with reduced rectal morbidity. These results have been corroborated by several Phase II and III clinical trials and subsequent meta-analysis. There are several areas for future research, including the role of hydrogel spacers in prostate stereotactic beam radiotherapy and post-radiotherapy local recurrence. ConclusionsHydrogel spacers provide a low-morbidity method to potential reduce rectal toxicity after radiation therapy in men with prostate cancer. Data outlining sexual function and oncological outcomes are limited to date. Future studies, currently being conducted, may provide further clarification of the role of hydrogel spacers in prostate cancer management.

Patient-Reported Outcomes 12 Years after Localized Prostate Cancer Treatment

“…[6][7][8] The increased fecal leakage found in ProtecT was beyond the shorter follow-up in the cohort studies, and there is further need to investigate this and whether imageguidance and hydrogel-spacers reduce bowel toxicity in the longer-term. 20 The observational cohort studies concluded that little change was seen in PROMs after two years 8 and that treatment effects had attenuated by five years. 6 However, this ProtecT analysis at 7-12 years shows that harms did continue and change in the longer-term.…”

Population‐based patient‐reported quality of life outcomes following low‐dose‐rate versus high‐dose‐rate brachytherapy monotherapy for low‐intermediate risk prostate cancer

“…Another aspect of evolving practice that may impact on the QoL outcomes is the use of rectal spacer, which has been shown to reduce rectal dosimetry and toxicities. 13 An earlier study from Victoria has reported the use of rectal spacer with LDR-BT over our current study period 14 ; however, data on the use of rectal spacer were not collected in PCOR-Vic. Another variation in practice is the use of focal BT in Victoria 15 over the study period.…”

“…In Victoria, HDR‐BT was largely offered in two public institutions while LDR‐BT was offered by several radiation oncologists across both public and private institutions. Another aspect of evolving practice that may impact on the QoL outcomes is the use of rectal spacer, which has been shown to reduce rectal dosimetry and toxicities 13 . An earlier study from Victoria has reported the use of rectal spacer with LDR‐BT over our current study period 14 ; however, data on the use of rectal spacer were not collected in PCOR‐Vic.…”

The Use of Hydrogel-Based Materials for Radioprotection

“…Prior to undergoing radiotherapy, clinicians can place hydrogel spacers in between the target organ and surrounding healthy tissues, thereby providing patients with clinical benefits [ 45 ]. These hydrogel spacers are primarily applied in prostate cancer patients, but they have also been deployed in cervical, breast, and other cancers when radiotherapy is being performed [ 88 , 89 , 90 ]. A range of injectable hydrogels have been designed using polyethene glycol (PEG), HA, and collagen.…”