ED Causes - Prostate Disease and Surgery
What is the prostate?
The prostate is a donut shaped gland found only in men. It is roughly the size of a walnut. It is located just below the bladder. The prostate surrounds the urethra, which is the tube that carries urine from the bladder to the outside during urination or semen during ejaculation. The prostate produces about a quarter of the semen, the milky substance that comes out during ejaculation.
What is prostate disease?
The three most common problems that can develop in the prostate gland are:
- Inflammation, also known as prostatitis - this can be due to infectious or non-infectious causes. Infections can be treated with with antibiotics. Non-infectious inflammation is more difficult to treat.
- Prostate enlargement or benign prostatic hyperplasia (BPH) - BPH frequently occurs in men over the age of 50. It is a natural part of the aging process. BPH can result in a gradual squeezing of the urethra, sometimes making it hard to urinate. The symptoms associated with BPH are called lower urinary tract symptoms (LUTS).
- Prostate cancer -This is the most common cancer in older men and the second leading cause of cancer deaths in the US. Researchers estimate that about 225,000 men are diagnosed with prostate cancer and about 30,000 die of prostate cancer in the United States each year.
How does prostate disease cause ED?
Men with lower urinary tract symptoms (LUTS) are more likely to have ED. The more severe the LUTS, the more severe the ED. These difficulties may include getting up to urinate at night, having to urinate often and urgently and trouble urinating. Such symptoms can be due to BPH, studies have shown a strong and consistent link between LUTS, BPH and ED.
Surgical removal of the entire prostate gland for the treatment of benign prostate enlargement or prostate cancer, or surgical removal of the bladder and prostate for the treatment of bladder cancer often injure the nerves and arteries leading to the penis. This usually causes at least temporary ED. ED can also result from the various forms of radiation therapy that are used to treat prostate cancer. Also, hormone treatment for advanced prostate cancer, which occurs when prostate cancer has spread outside of the prostate to other organs, reduces a man's sexual desire and erection function.
Why is prostate surgery (radical prostatectomy) associated with ED?
In 2003, about 225,000 men were diagnosed with prostate cancer in the United States. Of these men, 45% received treatment by surgical removal of the prostate gland (radical prostatectomy.) The majority of those men who have had this surgery will experience temporary or permanent ED.
Radical prostatectomy is an operation that completely removes the prostate and the surrounding tissue. Prostate surgery can be:
- Nerve-sparing (keeping intact the nerves which lead to the erection chambers and provide the stimulation for erection)
- Non nerve-sparing (not preserving these nerves)
Even if the majority of the nerves are preserved in the surgery, temporary ED is common.
When the nerve-sparing technique is used, particularly bilateral nerve-sparing, permanent ED is less common than with non-nerve sparing surgery and recovery often occurs within the first year or two following the procedure.
ED from a non-nerve-sparing procedure is common and recovery of erectile function after a non-nerve-sparing technique is unlikely though not impossible.
Erectile function following surgery depends on an individual patient's age, anatomy, extent of cancer and preoperative sexual function.5 Most studies report that 50-80% of men who have a radical prostatectomy have some degree of ED for the first year after surgery even if the surgeon is able to spare all or part of the nerves.6 Even in bilateral nerve-sparing surgery, return of erectile function may take up to 12-24 months. Eventually though, erections adequate for vaginal penetration return in 40-80% of men. Unilateral nerve sparing technique produces results that are intermediate between bilateral and non-nerve sparing surgery. Also, duration of time from the surgery to treatment for ED can play a role in the effectiveness of different therapeutic options.
Other sexual complications following radical prostatectomy include the absence of ejaculation or dry orgasm (orgasm without discharge of semen) in all cases, and loss of penile length in some men.
Do men respond to PDE5 inhibitors after having prostate surgery?
The first line of treatment for ED following prostate surgery is oral medications, such as phosphodiesterase-5 inhibitors (PDE5i) - sildenafil (Viagra®), vardenafil (Levitra®) and tadalafil (Cialis®). About 70% of men respond in some fashion to oral drug therapy in the post-operative setting.
Since these drugs are designed to increase blood flow to the penis upon sexual stimulation, they require intact nerves and arteries. Men receiving the nerve-sparing prostatectomy generally have a better response.
Does self-injection therapy used after prostate surgery help erectile function?
Penile self-injections provide very effective treatment of ED after prostate cancer surgery. Some studies report that penile self-injections can achieve a 95% success rate. Self-injection therapy is usually used after trying oral medications because of the convenience of oral therapy.
The role of oral, self-injection, intraurethral and vacuum therapies after treatment for prostate cancer:
For men who have had surgical or radiation treatment for prostate cancer, evidence suggests that oral, self-injection treatments started soon after treatment may improve the chances for later recovery of natural spontaneous erections. Oral therapy can be used with any of the three PDE5 inhibitor drugs. There are three vasodilator drugs used for self-injection therapy:
- Alprostadil, a type of prostaglandin E1
Injection of Alprostadil may cause penile pain. If this occurs, lowering the dose of Alprostadil and/or mixing Alprostadil with papaverine and phentolamine may reduce or eliminate the pain. The prescription drug called MUSE is used in intraurethral therapy.
Penile implants are a third line therapy, with a success rate of about 80-90%. They are the single most reliable form of treatment for erectile dysfunction, and they provide an excellent solution to the problem of erectile dysfunction.
Is prostate surgery associated with penile shortening?
Decreased penile length is commonly experienced following radical prostatectomy. In one study, loss of penile length ranging from 0.5 to 4 cm (about 1/4 to 1½ inches) was experienced in 71% of men, although only 48% of men reported a loss over 1cm (about ½ inch). Some experts believe that penile shortening can be reduced by starting oral, self-injection, intraurethral and/or vacuum therapy a few weeks after surgery.
Is it normal for men to leak urine during an orgasm?
Some men may leak urine during sexual activity and/or orgasm following prostate surgery, but the amount and frequency of leakage usually decrease over time. One way to help avoid leaking is to empty the bladder completely before sexual intimacy. Strategies used to minimize this problem have included wearing condoms, certain medications (the antidepressant imipramine, for example) and the use of a constriction band after the achievement of an erection (like the ACTIS tension band).