Abstract
An ectopic ureter is a rare male anomaly. We report a case of robot-assisted radical prostatectomy for prostate cancer in a patient with an ectopic ureter and a duplicated collecting system. A 71-year-old man was diagnosed with prostate cancer. Preoperative evaluation identified a left ectopic ureter opening into the bladder neck. During robot-assisted radical prostatectomy, an attempt to preserve the ectopic orifice resulted in an extensive positive surgical margin. The patient subsequently developed biochemical recurrence and was treated with androgen deprivation therapy and salvage radiotherapy. His prostate-specific antigen level is now undetectable. Preoperative diagnosis of an ectopic ureter is crucial for surgical planning to avoid positive margins and complications. This anomaly should be considered if an unexpected tubular structure is encountered intraoperatively or if unexpected urinary leakage occurs postoperatively.