Penile Rehabilitation After Prostate Treatment: What the Evidence Supports

Penile rehabilitation is the practice of treating the penis after prostate cancer treatment in order to preserve the tissue, rather than waiting to treat erectile dysfunction once it has settled in. Most commonly it means taking a PDE5 inhibitor daily for months after surgery, sometimes combined with a vacuum device or injections.

The concept is sound. The evidence behind it is weaker than the confidence with which it is often prescribed.

The reasoning behind it

Erectile tissue depends on regular oxygenation. Erections, including the ones that occur during sleep, bring oxygenated blood into the corpora cavernosa. When the cavernous nerves are injured during prostatectomy, those erections stop, and the tissue spends months in a low-oxygen state.

Smooth muscle is lost and collagen accumulates. Tissue that has undergone this change cannot expand fully, and cannot compress the subtunical veins hard enough to trap blood. The result is veno-occlusive dysfunction, which is venous leak arising as a consequence of the surgery rather than as an independent condition.

Tal and colleagues tracked when this appears after radical prostatectomy and found venous leak in 8% of men within four months of surgery, 22% between four and eight months, and 50% between eight and twelve months. Prevalence correlated strongly with nerve-sparing status. The window in which the tissue changes is roughly the first year, which is why rehabilitation protocols concentrate there.

If the tissue can be kept oxygenated through that window, the reasoning goes, the fibrosis may be limited and more function preserved. Animal studies support this. Human trials are where it becomes complicated.

What the trials found

REINVENT randomized 628 men after bilateral nerve-sparing prostatectomy to nightly vardenafil, on-demand vardenafil, or placebo for nine months. On-demand dosing outperformed placebo. Nightly dosing, the actual rehabilitation hypothesis, did not.

Pavlovich and colleagues compared nightly against on-demand sildenafil in previously potent men after minimally invasive nerve-sparing surgery, in a randomized double-blind trial with placebo, and found no advantage for the nightly schedule.

REACTT randomized 422 men to daily tadalafil, on-demand tadalafil, or placebo for nine months, followed by a six-week drug-free washout. Daily tadalafil improved erectile function while men were taking it. After the washout, unassisted function was not improved by either dosing schedule. Daily tadalafil did significantly reduce penile length loss compared with placebo.

The distinction running through all of these is between drug-assisted and unassisted function. PDE5 inhibitors clearly help men have erections while they are taking them. Whether taking them on a schedule changes the underlying tissue, so that function is better once the drug stops, is not established. A Cochrane review of penile rehabilitation after prostatectomy reached the same broad conclusion.

After radiation, the picture is similar

The most rigorous preventive trial in radiation was RTOG 0831, which gave 5 mg of daily tadalafil or placebo to men undergoing radiotherapy for 24 weeks. Among 221 evaluable men, 79% on tadalafil retained erectile function at 28 to 30 weeks against 74% on placebo, which was not a statistically significant difference. At one year the figures were 72% and 71%. This is covered in more detail in our article on radiation and erectile function.

What this means in practice

None of this means rehabilitation is pointless, and it is not a reason to decline a protocol your urologist recommends. It means the expectation attached to it should be modest and accurate.

Taking a PDE5 inhibitor after prostate treatment is reasonable. It is well tolerated, it produces usable erections for many men, those erections oxygenate the tissue, and there is trial evidence that daily dosing limits penile length loss. Sexual activity during the recovery period has its own value.

What the evidence does not support is the stronger claim that a rehabilitation schedule will restore spontaneous, unassisted erections that would otherwise have been lost. Men who are told that, and who then find themselves dependent on medication at eighteen months, often conclude they did something wrong. They did not.

A practical position: take what is prescribed, use it, and judge it on whether it produces erections you can use rather than on whether it is repairing anything. If a protocol is producing nothing after several months, that is information to act on rather than persist through.

When retention is the remaining problem

Where the tissue change described above has already occurred, the limiting step is retention rather than inflow. Erections build and then fade, and increasing inflow with medication improves the start without improving the outcome. This is the pattern that a constriction device addresses.

Xialla slows venous outflow and is anchored so that it holds position during intercourse. It compensates for a retention problem mechanically. It is not a rehabilitation treatment: Xialla does not preserve tissue, prevent fibrosis, or improve unassisted function, and it works only when some degree of erection can be achieved to begin with, alone or with another treatment. The mechanism is set out in how Xialla reduces venous outflow.

Questions to ask

• What is the specific goal of the protocol you are recommending, and how will we know whether it is working?
• Is this aimed at helping me have erections now, or at long-term recovery?
• At what point would we change approach?
• If erections start but do not hold, what does that indicate about the tissue?
• Is a referral to a sexual medicine specialist appropriate, and when?

Related reading

• Supporting Sexual Function After Prostate Surgery
• Radiation Therapy and Erectile Function
• Venous Leak and Erectile Dysfunction Explained
• Blood Retention: How Xialla Reduces Venous Outflow

References

• Montorsi F, Brock G, Lee J, et al. Effect of nightly versus on-demand vardenafil on recovery of erectile function in men following bilateral nerve-sparing radical prostatectomy. European Urology. 2008;54(4):924–931. https://pubmed.ncbi.nlm.nih.gov/18640769/
• Pavlovich CP, Levinson AW, Su LM, et al. Nightly vs on-demand sildenafil for penile rehabilitation after minimally invasive nerve-sparing radical prostatectomy: results of a randomized double-blind trial with placebo. BJU International. 2013;112(6):844–851. https://pubmed.ncbi.nlm.nih.gov/23937708/
• Montorsi F, Brock G, Stolzenburg JU, et al. Effects of tadalafil treatment on erectile function recovery following bilateral nerve-sparing radical prostatectomy: a randomised placebo-controlled study (REACTT). European Urology. 2014;65(3):587–596. https://pubmed.ncbi.nlm.nih.gov/24169081/
• Pisansky TM, Pugh SL, Greenberg RE, et al. Tadalafil for prevention of erectile dysfunction after radiotherapy for prostate cancer: the Radiation Therapy Oncology Group [0831] randomized clinical trial. JAMA. 2014;311(13):1300–1307. https://jamanetwork.com/journals/jama/fullarticle/1853160
• Tal R, Valenzuela R, Aviv N, et al. Persistent erectile dysfunction following radical prostatectomy: the association between nerve-sparing status and the prevalence and chronology of venous leak. Journal of Sexual Medicine. 2009;6(10):2813–2819. https://pubmed.ncbi.nlm.nih.gov/19686421/
• Philippou YA, Jung JH, Steggall MJ, et al. Penile rehabilitation for postprostatectomy erectile dysfunction. Cochrane Database of Systematic Reviews. 2018;10:CD012414. https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD012414.pub2/full

If you have questions about anything in this article, write to us at hello@xialla.com. We read and answer every message.