A 65-year-old man presented with a change in bowel habits 28 months after colonic resection for carcinoma. FDG PET/CT imaging was performed to assess for recurrent disease. This showed a 3-cm presacral soft tissue mass within which there was avid FDG uptake consistent with local recurrence. This mass had resulted in obstruction of the left distal ureter with resultant hydronephroureter; in addition, there was evidence of calyceal rupture with extravasation of FDG-containing urine into the perirenal space. The patient had no symptoms related to this renal abnormality and the calyceal rupture was therefore managed conservatively.