Nerve grafts may restore sexual function after prostate surgery
[A first-person story of the procedure is at Phoenix5.]
DANA POINT, Calif. (AP 8/13/01) — Salvaging a nerve from the ankle, surgeons have found they can rewire the penis so men achieve erections and have sex after operations to remove their cancerous prostate glands.
Doctors say the nerve grafts are not as good as the original nerves, but they do allow some men to regain sexual function when they otherwise would be undoubtedly left impotent.
"It seems to have promise, certainly over doing nothing," said Dr. Joseph J. Disa, a plastic surgeon who performs the surgery at Memorial Sloan-Kettering Cancer Center in New York City. He outlined the new approach Wednesday at an American Cancer Society meeting at Dana Point.
Usually, doctors can preserve male sexual function after prostate surgery by saving the two nerves that carry signals to the penis to fill with blood, allowing erections. But if the cancer is too close to the nerves, one or both of them must be cut, often leaving patients impotent.
The new approach uses a stretch of nerve removed from the ankle to fill in the gap left between the two severed ends of these nerves, which run next to the prostate gland.
Dr. Peter Scardino, a pioneer of the procedure, estimates that perhaps one-third of men who have prostate cancer surgery might benefit from the nerve grafts if the technique proves out in further testing.
Prostate cancer is the most common cancer among U.S. men and the second leading cancer killer after lung cancer. This year, 185,000 new cases are expected, and 32,000 men will die from it.
The nerve graft approach was first done in 1997 at Baylor College of Medicine in Houston by Scardino, a urologist, and Dr. Rahul Nath, a plastic surgeon. It has now been done on more than 300 men at several U.S. hospitals but is still considered experimental.
"It's early data, but the concept is a great one," said Dr. Mark Litwin of the University of California, Los Angeles. "It makes complete sense to do this."
The most impressive results so far are among men in whom both of the so-called cavernous nerves have been cut during prostate removal. Such men virtually never regain the ability to have intercourse spontaneously.
Though numbers are small, the data so far suggest that after nerve grafts, about one-third are able to have sex without the need for injections or drugs such as Viagra.
"The important part of this is that anybody recovered," said Scardino.
The cavernous nerves are 3 to 4 millimeters in diameter and difficult to find. Because of this and other problems, Disa said the grafts must be done during the original prostate operation and cannot be put in later.
In early stage prostate cancer, doctors can usually take out the tumor without cutting the nerves. However, if the cancer appears to abut the nerves, one or more must be cut to minimize the chance of leaving behind microscopic bits of cancer.
Usually, about a 5-millimeter stretch of the nerve is removed. To repair the damage, doctors adept at reconstructive microsurgery take out a piece of the sural nerve, which runs along the ankle, and fill in the gap.
Disa said it takes two years to know for sure whether the graft will work. During the first six months nothing happens, but erections gradually return.
When doctors can save both of the original nerves, about three-quarters of patients recover their sexual function. When one nerve is cut, this falls to about one-third.
Disa said the results so far suggest that if both nerves are cut, the grafts can restore erections to about one-third, while perhaps another third can get erections with the help of Viagra.
When patients have one original nerve and one graft replacement, about 70% appear to have normal sexual function.
"We are at a point where weve been able to show this works," said Disa. "Now we need a randomized controlled study where an objective measurement of erectile function is done before and after surgery. One problem is trying to get men to go into the control group. They're not too interested in that."
Among other places experimenting with the surgery are Columbia University, Cornell University, the University of Washington and the University of Michigan.