Robot‐Assisted Radical Prostatectomy in a Patient With a Rectal Fistula Following Hydrogel Spacer Placement

Introduction The polyethylene glycol‐based hydrogel spacer (SpaceOAR; Boston Scientific, Marlborough, MA, USA) reduces the rectal dose during prostate radiotherapy and rarely leads to rectal ulceration or fistula formation. We report a case in which robot‐assisted radical prostatectomy (RARP) was successfully performed following this rare complication. Case Presentation A 62‐year‐old man developed hematochezia after SpaceOAR placement. Magnetic resonance imaging (MRI) and colonoscopy revealed a rectal ulcer with a fistula. The patient initially received bowel rest and antibiotics, followed by an ileostomy. After endoscopic confirmation of reepithelialization and MRI evidence of hydrogel resorption, the stoma was closed. At his request, the patient subsequently underwent RARP, which was safely performed with transrectal ultrasound guidance. Conclusion RARP after a hydrogel‐related rectal fistula is technically feasible; however, it should ideally be performed at an experienced center.