A massive pelvic mucocele presenting as a cystic sacral mass

We present a man, with a complex medical and surgical history, who had a large pelvic non-appendiceal cystadenoma, presenting as a cystic sacral mass causing obstructive urinary symptoms and renal failure. Mucocele should be included in the differential diagnosis of patients who present with large sacral masses, and who have a significant history of pelvic and abdominal surgery and inflammatory bowel disease.