Ureterosigmoidostomy is a method for total diversion of the urinary stream into the sigmoid colon, away from the urinary bladder and lower urinary tract, and the anus providing the continence mechanism for urine as well as for feces. However, this type of urinary diversion has multiple serious mid-and long-term complications, including cancer at the anastomotic site, ascending urinary infection, hyperchloremic metabolic acidosis, electrolyte imbalance, incontinence, and urinary stone. We present here a case of adenocarcinoma at the ureterosigmoidostomy site, performed for ectopia vesicae, 47 years ago.