What is a fistula?
A fistula is an abnormal connection between two organ systems. A prostate-rectal fistula is an abnormal connection (hole) between the prostate and the rectum that allows urine to pass freely into the rectum and stool to pass freely into the prostate.
What are the common symptoms of a prostate-rectal fistula?
- Chronic urinary tract infections
- Air in the urine
- Particulate matter, namely food or stool in the urine
- Urine leaking out of the rectum or very watery stools
- Pelvic and rectal pain, often making it difficult to sit down
What causes a prostate-rectal fistula?
Prostate-rectal fistulas typically occur as side effects of prostate cancer therapy.
Prostate Surgery: After or during prostate cancer surgery (either open or by robotic assisted laparoscopy) a hole can accidently be created when the prostate is surgically dissected off the rectum. This is a surgical misadventure. If the rectal injury is recognized during surgery, it can often be fixed at the time. However, when the injury is not recognized initially and only recognized days to weeks later, then this requires a complex surgical repair.
Prostate Radiation: injuries to the rectum and the prostate typically occur after radio-active seed implants for prostate cancer. Proper placement of the seeds can be tricky. The seeds can be placed too close to the outer edge of the prostate and the rectum and thus the radiation “burns” the tissue, resulting in an ulcer in the prostate and rectum. Over time, the ulcer can punch a hole connecting the two organs. Radiation damage continues to worsen as time passes. An ulcer in the rectum can be very painful because of chronic infection, and can make sitting difficult.
How are fistulas that occur as a side effect of surgery repaired?
Small fistulas that are only the result of a surgical misadventure and no associated radiation therapy or cryotherapy can often be repaired by a York Mason repair – a rectal splitting repair of the fistula where a skin incision is made in the gluteal fold and deep into the rectal wall.
Another option is to dilate the anus, and through the anus surgically create a sliding flap of rectal wall to cover the hole (fistula).
If the fistula is large or there is associated radiation, then the fistula repair is very difficult and complicated. Here the repair usually requires a muscle flap from the leg, transferred to the prostate to act as a patch. If the hole is big, a patch of lining from the inner cheek is also harvested and sewn to the prostate.
How are radiation induced fistulas repaired?
Radiation fistulas are the most difficult to repair. The process from start to finish often requires more than one surgery and a period of at least 6 months.
Treatment usually requires both fecal and urine diversion - a colostomy or loop ileostomy to bring the stool to the skin. This requires wearing a stoma or ostomy bag (appliance) to collect the stool.
Repairing the fistula (hole) requires a muscle flap from the leg or buttock and often a graft from the mouth. After surgery, it takes a month or two before all the tubes are removed.
Once the fistula is healed, an interval of 3 months or more is allowed to pass before taking down the ostomy (stool bag).