Nerve-Sparing Prostatectomy: When It's Safe, When It Isn't, and How the Decision Is Made
The questions most people bring into a prostate cancer surgery consultation aren't always the ones they say out loud. Will I be incontinent? Will I be able to have erections? If you try to spare the nerves, are you going to leave cancer behind?
These are the right questions. They sit at the heart of one of the most consequential decisions in prostate cancer surgery — whether to attempt nerve-sparing, to what extent, and on which side.
This article explains what nerve-sparing involves, what it can and cannot achieve, and how I approach the decision with patients when the answer isn't straightforward. Because often, it isn't.
What are the nerves being spared?
The neurovascular bundles are two collections of nerves and blood vessels that run along either side of the prostate, very close to the tissue that needs to be removed. These nerves are responsible for the signalling that triggers erections.
Because they sit immediately adjacent to the prostate, removing the prostate always puts them at risk. Nerve-sparing is the attempt to preserve them — on one or both sides, and to varying degrees — during the operation.
It is not a technical add-on. It is a selective decision made within a cancer operation.
What nerve-sparing can achieve
In the right patient, with the right cancer, nerve-sparing can meaningfully support recovery of erectile function after surgery.
But three things need to be true for that to be realistic:
The cancer has to permit it. If the tumour is close to or involving the nerve bundle, attempting to spare it risks leaving cancer behind. That is the wrong trade-off.
Baseline function matters. People who have good erectile function before surgery, and who are younger, non-smokers, and without significant vascular disease or diabetes, tend to have the best recovery. Nerve-sparing in someone with significant baseline dysfunction before surgery is unlikely to produce dramatically different results.
Recovery takes time — more than most people expect. Even with successful nerve-sparing, erections don't return immediately. The nerves undergo a period of trauma from being handled and exposed during surgery, even if they aren't cut. Recovery is measured in months. For some people it can be longer than a year. Understanding this before surgery matters, because the early post-operative period — when function hasn't returned — can be distressing if the expectation wasn't set realistically.
What nerve-sparing cannot guarantee
Nerve-sparing creates the conditions in which recovery is more likely. It does not guarantee it.
It cannot overcome pre-existing vascular or neurological factors, age-related changes, or the cumulative impact of other treatments if radiation or hormone therapy is part of the pathway.
More importantly: nerve-sparing that compromises cancer removal is not a good outcome. A positive surgical margin — where cancer cells are present at the edge of the removed tissue — means residual disease, and may mean further treatment. The goal of surgery is cancer control. Nerve-sparing is pursued within that goal, not instead of it.
Cancer control comes first. Always.
Bilateral versus unilateral: not always both sides
One thing that often surprises patients is that nerve-sparing is not automatically bilateral — meaning both sides.
Sometimes one nerve bundle can be preserved and the other cannot, because the tumour is located on one side. Unilateral nerve-sparing can still be meaningful functionally — one intact bundle may still contribute to recovery. But it is different from bilateral sparing, and the outcomes are different too.
This is why the pre-operative MRI is so important. It helps map where the tumour is within the prostate and how close it sits to each bundle. If imaging shows a suspicious lesion abutting one side, that changes what is safe on that side — regardless of what a patient hopes for.
The conversation about nerve-sparing is therefore rarely "yes or no." It is more often: on which side, and to what degree, is it safe to attempt?
How the decision is made
Nerve-sparing decisions sit in a genuinely uncertain space, and patients are better served by honesty about that uncertainty than by reassurance that isn't warranted.
What I try to do in consultation is be specific rather than general. Not "nerve-sparing is usually possible" — but: here is your MRI, here is where your tumour is, here is what I can and can't preserve safely, and here is what a realistic recovery might look like for you — not for the average patient in a study.
The key clinical factors are:
Cancer location and extent. Where the tumour sits within the prostate, and whether it appears to extend toward or beyond the capsule, is the most important determinant. A high-quality MRI is central to this assessment.
Grade and risk category. Higher-grade cancers warrant more caution. The closer the cancer is to the bundle, the less margin there is for preservation.
Biopsy pattern and PSA in context. The distribution of positive cores and PSA level help build a picture of disease extent within the gland.
Baseline sexual function. A frank pre-operative conversation about current function sets realistic expectations and shapes what a meaningful recovery would actually look like.
Patient priorities. Some people prioritise certainty of cancer clearance above everything. Others place great importance on preserving sexual function. Both are valid, and the plan should reflect the individual — not what the surgeon thinks should matter.
Where the answer is genuinely unclear — where the MRI shows a lesion close to a bundle but not definitively involving it — the final decision may not be made until surgery, when the tissue can be seen directly. If the dissection plane looks concerning, I will extend the resection. That is not a failure of planning. It is intraoperative judgement, and it is the right thing to do.
Does robotic surgery help?
It can — in the right hands and the right setting.
The robotic platform provides magnified, high-definition 3D visualisation. The neurovascular bundles are small, delicate structures, and seeing them clearly matters. Robotic instruments may facilitate more controlled dissection along the tissue planes adjacent to the bundles — particularly where magnification and fine instrument movement matter most.
What this means in practice is that a surgeon experienced in nerve-sparing technique may be able to execute it more carefully and consistently with robotic assistance — particularly for the most delicate steps.
But to be direct: robotic surgery does not make someone a candidate for nerve-sparing who isn't one. It does not override tumour biology. The decision to attempt sparing — and the judgement to abandon it intraoperatively if needed — belongs to the surgeon, not the platform.
Questions worth asking before surgery
Based on my MRI and biopsy, am I a candidate for nerve-sparing on one or both sides?
What specifically makes you cautious on one side?
If you find something unexpected during surgery, what would change your approach and how would you decide?
What is a realistic recovery timeline for erectile function in my situation — not the average, but mine?
What rehabilitation support is available, and when does it usually start?
A surgeon who gives specific, individualised answers to these questions — rather than general reassurances — is telling you something important about how they approach the decision.
After surgery: the role of rehabilitation
Recovery doesn't end when surgery does. How the post-operative period is managed can affect functional outcomes.
Penile rehabilitation — the use of erectile aids such as PDE5 inhibitors or vacuum devices in the months after surgery — is commonly recommended by many surgeons, often before erections return spontaneously. The principle is that maintaining blood flow and oxygenation to penile tissue during the recovery period may support nerve regeneration over time. Protocols vary between surgeons and patients, and the evidence, while supportive, continues to evolve.
What tends to hold true is that engaging with this process early, with realistic expectations, is better than waiting. For patients who want to pursue active rehabilitation, support from the surgical team — and where appropriate, sexual health services — makes a meaningful difference.
A final note
Nerve-sparing prostatectomy, done appropriately in the right patient, is a meaningful and achievable part of prostate cancer surgery. It reflects both surgical precision and careful patient selection.
But the most important conversation isn't really about technique. It's about what you are trying to preserve, what the cancer allows, and what a realistic outcome looks like for you — not in general, but specifically. If you are weighing surgery for prostate cancer, the key question is not whether nerve-sparing sounds appealing in theory, but whether it is safe and appropriate in your case.
If you have been diagnosed with prostate cancer and are considering surgery, the nerve-sparing conversation is worth having in detail. Contact the rooms to discuss whether it is appropriate in your situation.
For more on the robotic prostatectomy procedure, see Robotic Radical Prostatectomy. For the broader prostate cancer treatment pathway, including active surveillance and radiation options, see Prostate Cancer.
Clinical note: This article provides general information and is not a substitute for individual medical advice. Management should be based on personalised assessment, staging and discussion of options.
Last reviewed: April 2026
About the author: Dr Deanne Soares is a Melbourne-based urologist with a subspecialist focus in robotic prostate, kidney and bladder cancer surgery.
