Prospective analysis of hydrogel spacer for prostate cancer patients undergoing radiotherapy

The purpose of this study was to report on the dosimetric benefits and late toxicity outcomes following injection of a hydrogel spacer (HS) between the prostate and rectum for patients treated with prostate radiotherapy.

A total of 76 patients with a clinical stage of T1-T3a prostate cancer underwent general anaesthesia for fiducial marker insertion plus injection of the HS into the peri-rectal space prior to intensity modulated radiation therapy (IMRT) or volumetric modulated radiation therapy (VMAT). Spacer safety, dosimetric benefits and the immediate to long-term effects of gastrointestinal toxicity (GI) were assessed.

There were no postoperative complications reported. Mean prostate size were 66.0cc (25.0cc - 187.0cc). Rectal dose volume parameters were observed with volume of rectum receiving 70Gy (rV70), 75Gy (rV75) and 78Gy (rV78) were 7.8%, 3.6% and 0.4%. 21% (16/76) developed acute grade 1 GI toxicities but all were resolved completely by 3 months post-treatment. 3% (2/76) developed late grade 1 GI toxicities. No patients experienced acute or late grade 2+ GI toxicities.

Injection of HS resulted in a reduction of irradiated rectal dose volumes along with minimal GI toxicities; irrespective of prostate size This article is protected by copyright. All rights reserved.

BJU international. 2018 Mar 09 [Epub ahead of print]

Michael Chao, Huong Ho, Yee Chan, Alwin Tan, Trung Pham, Damien Bolton, Andrew Troy, Catherine Temelcos, Shomik Sengupta, Kevin McMillan, Chee Wee Cham, Madalena Liu, Wei Ding, Brindha Subramanian, Jason Wasiak, Daryl Lim Joon, Sandra Spencer, Nathan Lawrenstchuk

Genesis Cancer Care Victoria, Ringwood, Australia., The Austin Hospital, Heidelberg, Australia., The Bays Hospital, Mornington, Australia., The Valley Private Hospital, Mulgrave, Australia., St Vincent's Hospital, Fitzroy, Australia., Ringwood Private Hospital, Ringwood East, Australia.