Dr. Mohit Khera, a urologist specializing in male infertility, male and female sexual dysfunction, and declining testosterone levels in aging men, is the Director of the Laboratory for Andrology Research and the Medical Director of the Executive Health Program at Baylor College of Medicine in Houston, Texas.
Prostatepedia spoke with him recently about erectile dysfunction after prostate cancer.
How common is erectile dysfunction after prostate cancer?
If you look at the literature, the data can vary significantly: anywhere from 10% to as high as 90%. You see such a wide fluctuation, because there are so many variables. A critical factor is surgeon skill.
Surgeons who have more skill in preserving the cavernosal nerves have better outcomes.
But there are other factors, such as patient comorbidities; some people believe the testosterone levels matter or whether the man has a willing partner. Our research was one of the first to show that patients with a partner who wants to engage in sexual activity tend to recover their erectile function faster. That makes sense: they have someone to have sex with. Men without a willing partner may not recover as quickly because there is less motivation to recover.
Think of the penis as a muscle, like your biceps muscle muscle in your arm. If I put your arm in a cast today and then took the cast off after six months, there would be significant atrophy of that muscle. It would be withered. The penis is the same. If you don’t use the penis, it will atrophy.
Erectile dysfunction rates start to increase significantly in men in their 50s. What else happens in the lives of men in their 50s? Their partners usually go through menopause. These men are not having sex; that’s when you start seeing a significant amount of erectile dysfunction.
Men who have a willing partner are more motivated to use the medications to engage in sexual activity and to exercise those muscles. That tends to result in better erectile function down the road.
Are some prostate cancer treatments associated with a higher rate of erectile dysfunction than others?
Cryotherapy tends to have the highest rate of erectile dysfunction. Cryotherapy basically means freezing the prostate. When you freeze the prostate, you also generally freeze the nerves and if you freeze the nerves, you get erectile dysfunction. The rate for erectile dysfunction following cryotherapy is quite high, but then most patients don’t do cryotherapy.
The majority of men in this country choose either surgery or radiation.
Surgery has a higher rate of erectile dysfunction in the immediate postoperation period. Over the course of 12 months, men tend to regain their erectile function. Radiation tends to affect the patient later, say five to 10 years down the road, and can increase the erectile dysfunction rates in this population.
What about hormonal therapy?
Hormonal therapy is not considered a primary therapy; it is an adjuvant or neoadjuvant therapy. Hormonal therapy can have a devastating impact on erectile function. It significantly reduces testosterone levels. That is how it works. When you reduce testosterone levels, you reduce a man’s ability to get an erection. We use hormonal therapy in men with high-grade disease when we give them radiation.
We also use hormonal therapy in men with metastatic prostate cancer.
Sometimes we use hormonal therapy in men with highgrade cancer with a rising PSA after radical prostatectomy. Again, hormonal therapy is not considered primary therapy. These are adjuvant therapies.
Is erectile dysfunction after prostate cancer a result of the treatments a man gets, or is there something about the cancer itself that causes erectile dysfunction?
The diagnosis itself can cause psychogenic erectile dysfunction. In other words, many men can have an increase in erectile dysfunction rates after they receive a diagnosis, but before surgery. Many women are also concerned. (I had the wife of a prostate cancer patient call me to ask if she could get cancer if she had sex with her husband.)
The fact that you have a cancer in the genital region has a psychological impact and can affect sexual function. You’re worried about what is going to happen. However, more severe erectile dysfunction usually happens after surgery.
Today, most patients have nerve-sparing prostatectomies, which means that we spare the nerves during surgery. After surgery, many patients experience a process called neuropraxia, which means temporary paralysis of the nerves because they’ve been manipulated. It can take some time for those nerves to recover. We know that full recovery of erectile function typically occurs