Impotence. It is, perhaps, one of the most disturbing words a man can hear. And for men battling prostate cancer, it is a very real possibility. However, a nerve grafting surgical procedure may prevent impotence that often occurs after surgery to remove the prostate gland.
Cut to Cure
Surgical removal of the prostate gland, called a radical
, is often done when cancer is contained within the prostate gland (T1 or T2 cancers). This surgery can be very effective at curing
. However, it also carries a high risk of causing long-term
, or impotence. This risk is especially high when one or both of the cavernous nerves are cut.
The cavernous nerves are two tiny nerves situated alongside the prostate gland that carry signals to the penis to fill with blood and become erect. In some cases, the surgeon is able to leave these nerves intact and possibly preserve erectile function.
But for technical reasons, a portion of one or both may need to be removed. The two nerves run along the sides of the prostate, and this is where the majority of the glandular prostate is located. Because it is the glandular or lateral prostate where cancer most often develops, often times the nerves are too close to the cancer itself to be spared. Some men—about one-third of those with just one nerve left intact—are able to have an erection; this depends on factors such as age and sexual function before surgery. When both nerves are severed, impotence is virtually certain.
Not all cases of impotence after prostatectomy result from trauma to the cavernous nerves. However, since this is a relatively common cause, doctors theorized that patching up these nerves could restore erectile function in many patients.
In 1997, Peter Scardino, MD, a urologist, and Rahul Nath, MD, a plastic surgeon, performed the first nerve grafting during a radical prostatectomy. They removed a tiny portion (a graft) of the sural nerve, which is located in the ankle, and used it to reconnect the severed cavernous nerve. Since then, more and more health centers have begun offering this procedure, though it is still considered experimental.
The cavernous nerves are only about 3-4 millimeters in diameter. Therefore, grafting must be done during the prostatectomy, when the nerves are first cut; otherwise, the cut nerves would be virtually impossible for a surgeon to find and repair. Each graft takes about 30 minutes.
The portion of nerve removed from the ankle is only about 5 millimeters long. The main risk involved is a rare and treatable one—the formation of a painful growth at the end of the sural nerve where it has been cut.
The grafted nerves do not function as well as the original intact nerves, but can restore erectile function to about 1/3 of men who have had both cavernous nerves cut and grafted during surgery. Another 1/3 of men receiving two grafts are able to achieve an erection with the help of the drug
. Among men who have one intact nerve and one grafted, about 70% regain sexual functioning. Alternative procedures using other grafted nerves have been developed and have been reported to result in similar or better preservation of erectile functioning.
Erectile ability is not restored immediately after the grafting procedure. During the first six months, there is typically no function, but erections gradually return in time. It can take up to two years to know for certain if the grafting will work. Typically, younger patients are more likely to regain sexual function.
Grafting is not appropriate for all men with prostate cancer. But this does not mean that impotence is inevitable. Other options to help restore erectile function—which can also be used by men who have received a graft, but need additional aid—include:
—a device surgically placed in the penis to help a man achieve erection. There are three main types: rods, simple inflatable devices, and complex inflatable devices.
Prostaglandin E1—a substance naturally produced in the body that can produce erections. As a medication, it can be injected with minimal pain into the base of the penis 5-10 minutes before intercourse, or introduced into the urethra as a suppository. The dosage can be increased to prolong erection. Side effects include pain, dizziness, and prolonged erection.
Vacuum devices—mechanical pumps placed around the entire penis before intercourse to produce an erection. The mechanics of these devices may not allow for ejaculation.
Sildenafil citrate (Viagra)—a drug used to treat male impotence. Viagra will not work if both nerves have been damaged or removed. The most common side effects of Viagra are headache, flushing (skin becomes red and feels warm), indigestion, light sensitivity, and other visual problems. People who take nitrate medications to manage
and other heart problems should never use Viagra. These medications can interact to cause very low blood pressure, a complication that can be fatal.
Please be aware that this information is provided to supplement the care
provided by your physician. It is neither intended nor implied to be a
substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER
IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the
advice of your physician or other qualified health provider prior to
starting any new treatment or with any questions you may have regarding a