Nanoknife™ for prostate cancer

Nanoknife™ uses electrical pulses to create tiny holes in the prostate cancer cells, causing them to die. Nanoknife™ is a brand name. It is also called Irreversible Electroporation or IRE.

Nanoknife™ is a type of focal therapy. In focal treatment, we only treat the area of your prostate affected by cancer. If some areas of your prostate have very slow-growing cancer, we may not treat them right away. Instead, we watch these areas closely and treat them if the cancer grows or changes.

The benefits of Nanoknife™ include: 

• The aim is to cure the prostate cancer.
• Your recovery will be quicker than if you have an operation. This is partly because the procedure is delivered by needles, which is less invasive than surgery, where you’ll have a wound.
• You are likely to have fewer side effects compared to treatments that target the whole prostate, such as surgery and radiotherapy.
• You will normally go home the same day, a few hours after the procedure.
• Your recovery will be short so that you can soon return to normal daily living.
• You can have Nanoknife™ again or a different prostate cancer treatment, if needed.

Below are the side effects and risks of prostate Nanoknife™. Side effects are common, but often minor. Risks are less likely but can be more serious. Speak to your urology doctor or CNS if you have any concerns about the side effects and risks. 

• Peeing more often or more urgently. Most men experience these symptoms for a few days or weeks. This generally settles without the need for treatment.
• Blood in your urine. Most men will see a little blood in their urine after the procedure, in much the same way as with their prostate biopsy. This isn’t dangerous and will settle within a few days or sometime a few weeks. Occasionally blood clots in the urine may make it difficult to pee and a catheter may be needed again. Please contact your CNS if you’re worried about this. Serious or harmful bleeding is very rare after Nanoknife™ treatment.
• Debris or tissue in your urine. As the treated part of the prostate dies, small pieces are sometimes passed into the toilet with the urine. This isn’t dangerous unless it blocks your urine flow. This happens rarely. If you have a blockage or pain when you pee, please contact your CNS.
• Urine infection: About 10 in 100 men will get a urine infection after Nanoknife™. If this happens, we can usually treat it with antibiotic tablets. You will be given some antibiotics during and after Nanoknife™ to keep the risk as low as possible.
• Urine leaks. This is also called urinary incontinence. This happens to 1 in 100 men. It is very rarely permanent. If the urine leaks continue for a while, we can teach you pelvic floor exercises.
• Erection problems. Nanoknife™ can sometimes affect the nerves that help with erections. Research shows that 90 out of 100 men who had good erections before the procedure will continue to have good erections afterward. Around 30 out of 100 men may need medicines like Viagra, which they didn't need before.
• Dry orgasm. This is also called retrograde ejaculation. It is common to see a smaller amount of semen after prostate cancer treatments such as Nanoknife™. The prostate makes most of the fluid that mixes with sperm to form semen. Nanoknife™ can affect how much fluid your prostate produces. After the procedure, you may notice that you produce less or no semen during orgasm. How much semen you produce afterwards depends on which part of your prostate we treat.
• Fistula. This is a hole between your rectum and urethra. Your urethra is the tube that carries urine from your bladder to the tip of your penis. Very rarely during the procedure your rectum may get damaged. When this happens, urine can pass into it. This happens to less than 1 in 700 men. Although very rare, it is serious. For most men, the hole will heal if they wear a catheter for several months. Some men may need an operation to repair the hole and create a stoma. A stoma is an opening made on the surface of your tummy. Part of your bowel is brought to the surface and your poo collects in a bag.
• Need for further treatment. After five years, about 10 in 100 men may need another Nanoknife™ procedure. About 10 in 100 men may need surgery or radiotherapy.
• There are also some risks linked to having general anaesthetic. You can visit the Royal College of Anaesthetists website for more information.

This depends on the type of prostate cancer you have. Your urology doctor will explain which risk group you are in. If you’re not sure, you can ask your doctor or CNS to explain it to you.

If you have low or medium-risk prostate cancer

You may not need treatment right away. Instead, we can monitor it with active surveillance for five to ten years or sometimes longer. This means you will have regular tests to check the cancer. If there are signs that your cancer is progressing, we will offer you treatment.

At UCLH, 1 in 3 men with low to medium-risk cancer needed treatment after five years. Some men choose treatment right away because they feel uneasy waiting. However, studies show that survival rates are very similar whether you have treatment now or later.

Note: If your cancer is very low-risk and doesn’t show on an MRI scan, treatment is very unlikely to help. This is because very low-risk cancers are unlikely to cause you any problems in the future.

If you have a higher-risk prostate cancer

If you choose not to have Nanoknife™ or another treatment, there is a risk that the cancer could grow or spread. Delaying treatment might mean it is no longer an option later. And going without treatment could pose a serious risk to your life.

Nanoknife™ is usually just one of the options to treat your prostate cancer. Your urology doctor or CNS will tell you about all the options for you. We have more information about them on our treating prostate cancer web page.  

There isn't a "best" treatment for localised prostate cancer. That’s because each treatment has advantages, disadvantages and side effects, and affects men differently. You may not experience all the possible side effects. Consider how the side effects may impact your daily life before choosing a treatment. Your healthcare team is here to support you to make the best choice for your needs and lifestyle.

Pre-assessment appointment

We will give you a pre-assessment clinic appointment several weeks before your Nanoknife™. At the appointment, the nurse will check if you are well enough for the procedure and will:

• Explain the anaesthetic you will have.
• Ask about your medical history. This is to help the anaesthetist prepare for your procedure.
• Tell you if you should continue taking your medicines.
• Let you know when to stop eating and drinking before Nanoknife™.
• Advise what to bring on the day.

Plan your travel home

Please arrange for someone to take you home after your Nanoknife™ and stay with you overnight. If you don’t have someone to take you home, we will ask you to stay in the hospital overnight. It’s ok to use public transport if you need to.

Arrange to have your catheter removed

You will have a urinary catheter placed in your bladder during Nanoknife™ to drain urine. This will stay in place for three to seven days.

We prefer you to have your catheter removed at UCLH. But if you’d like it done closer to where you live, contact your GP surgery to arrange this before your Nanoknife™. You should arrange this before as some local services may not offer catheter removal. If you haven’t arranged it before your procedure, you will have your catheter removed at UCLH.

It’s important you’re involved in all the decisions about your care and treatment. If you choose to have Nanoknife™, by law we must ask you to sign a consent form before you have it. This confirms that you agree to have Nanoknife™ and understand what it involves. Your surgeon will explain all the risks, benefits and alternatives again before you sign the consent form. If you are unsure about any aspect of Nanoknife™, please tell your urology doctor or CNS.

Before Nanoknife™

• Empty your bowels an hour or two before you are due to have the procedure. This helps the ultrasound probe get a good view of your prostate. 
• The anaesthetist gives you a general anaesthetic which means you will be asleep during the procedure.
• The surgeon inserts a catheter through your penis into your bladder. This is to help your urine drain whilst the prostate is swollen after treatment. It stays in place for three to seven days. Very rarely we need to insert a catheter through your tummy into your bladder instead.

During Nanoknife™

• The surgeon puts an ultrasound probe into your rectum. This lets us see the prostate just as we did during your prostate biopsy.
• The surgeon inserts special needles through your perineum. Your perineum is the skin between your legs, behind your scrotum. These needles are guided into your prostate using ultrasound images. Three to five needles are usually inserted.
• Electricity flows between pairs of needles in sequence. The system uses high-power short pulse of up to 3000 volts, each lasting 90 microseconds. These pulses create small holes in the targeted area, causing the cells to die. Your body’s immune system removes the dead cells over the next few weeks.
• When the procedure is complete, the surgeon removes the needles and you’re taken to the recovery unit.

• You will stay in the day surgery unit until you are awake and have eaten and drunk something.
• You may feel some discomfort in your rectum and penis. Mild painkillers like paracetamol or ibuprofen usually help. Tell your nurse if you are still in pain and they can give you stronger painkillers.
• We may also prescribe you tablets to relax your prostate. These are called alpha-blockers, such as tamsulosin or alfuzosin.
• Before you go home:

1. We will show you how to empty and care for your catheter.
2. We will give you antibiotics to take for three to five days to prevent infection.
3. We will give you a contact number in case you have any problems at home.
4. Make sure you have your appointment for your catheter removal.

You can usually go home the same day as the procedure if you have someone to go with you. If you don’t have someone to take you home or if you have a certain medical condition, you may need to stay in the hospital overnight.

Most people recover from Nanoknife™ within one to two weeks. Most people return to work once their catheter is removed. Some people have longer off work, depending on their job. In the UK, you can sign yourself off work for a week. If you feel you need longer than this to recover, ask your doctor or nurse for a fit note (sick note).

• Drink 1.5 to 2 litres of fluid each day. This will stop you from becoming dehydrated, constipated or getting a urine infection. You may need more than this in hot weather. Drink lots of fluids for six to eight weeks after Nanoknife™. 
• Avoid constipation. Constipation might cause you to strain when you poo and could lead to blood loss. It can also make it harder to pass urine. We will give you a gentle laxative syrup when you leave the hospital to ease constipation. We will give you instructions on how much and how often you should take this. The laxative softens your poo making it easier to pass. Avoid constipation for six to eight weeks after Nanoknife™. 
• Keep the skin between your rectum and scrotum clean and dry. You should not need a dressing in this area once you leave the hospital. 
• Avoid activities which use a saddle for a few weeks – such as cycling, horse riding, or using an exercise bike or rowing machine.  
• Restart other exercises when you feel able to.

First 24 hours

Let your urine drain freely into the catheter bag (leg bag). At night, you can attach a larger night bag. 

After 24 to 48 hours

You no longer need to let your urine drain freely into the bag. Instead, you can let it collect in your bladder. To do this: 

• Detach the leg bag from the catheter and attach a catheter valve.  
• If the valve is already fitted, remove the leg bag from the valve.  
• When the valve is off (up position), your bladder will fill with urine.  
• When you feel the need to pee, open the valve to empty the urine into the toilet. 
• Close the valve again once you have emptied your bladder.

You might find it more comfortable to use the bag at night. The catheter can sometimes irritate your bladder and make you wake up needing to pee.

Caring for your catheter

You can find detailed instructions on our Caring for your urinary catheter web page. Ask your CNS or ward nurse if you’d like a paper copy of the information. 

Tips for draining urine

Emptying your bladder through the catheter valve can cause your bladder to collapse onto the catheter, which can be painful. To avoid this:  

• Open the valve slowly and let the urine drain gently.
• Stop draining when you feel your bladder is empty.
• Close the valve before it becomes uncomfortable.

Having your catheter removed

We will check how well your bladder empties once we remove the catheter in the clinic. We call this the ‘Trial WithOut Catheter’ or ‘TWOC’ clinic. This appointment is usually arranged for five to seven days after your procedure. You will normally be in the department for three to four hours for this appointment.

If you prefer to have the catheter removed nearer to where you live, contact your GP surgery to arrange this. You must arrange this before you have Nanoknife™ as it may not be available at all local hospitals and GP surgeries. You will get a UCLH TWOC clinic appointment if you have not arranged to have the catheter removed elsewhere.

After Nanoknife™, your GP and hospital must monitor you. Although many men are cured after having Nanoknife™, some may need further treatments. 

Follow-up appointment

After you have Nanoknife™, we’ll give you an appointment to see the surgical team. The appointment will be three months after Nanoknife™. The surgeon will ask if you have any problems peeing or getting erections. Please tell them if you notice any issues. You can also contact your CNS at any time to discuss these problems. We will offer you support or treatment if you need it. 

PSA tests

You will need regular PSA (prostate-specific antigen) blood tests after Nanoknife™. 

Your PSA levels will be checked regularly to monitor your recovery. We expect your PSA levels to go down after Nanoknife™. The amount of reduction can vary for each person. We don’t expect the PSA to drop to zero as some of your prostate has been left in place. 

• First PSA test: 3 months after Nanoknife™
• First year: Every 3 months
• After 1 year: If stable, every 6 months.

After one year, we will give you a PSA level to watch for. If your PSA goes above this level, contact us so we can review your care. We will ask you to provide a urine sample through your GP to check for infection. We’ll then ask you to repeat the PSA test six weeks later. We will not make a decision on your care based on a single result.

You will have yearly telephone appointments with your urology doctor or CNS to discuss your PSA results.

MRI scans

You will have an MRI scan 7 to 14 days after Nanoknife™ to check for any issues.

Please note: There is no routine appointment to discuss the results. Your doctor will go over them with you at your follow-up appointment three months after Nanoknife™. 

All patients have MRI scans at: 

• 1 year after treatment 
• 3 years after treatment 
• 5 years after treatment. 

You will have an appointment to discuss the results of these scans.

Other monitoring

We will monitor you for any urine or erection problems, and offer you support or treatment as needed. If you have trouble with your erections or urine symptoms, contact your urology doctor or CNS for help. We collect information about any urine and erection problems people have after the procedure. Sometimes we will send you an email asking about these side effects. It’s helpful if you can let us know how you’re doing when we get in touch.

We hope this information is helpful. If you have any questions, please ask your urology doctor or CNS.

• Prostate cancer treatments choices
  A video developed by North Central and East London Cancer Alliance to help you learn about prostate cancer treatments. 
• UCLH Macmillan Support and Information Service 
  020 3447 8663 (general enquiries) 
  020 3447 3816 (support and information helpline) 
  They provide: 
  • Emotional support, advice and information 
  • Welfare and benefits advice 
  • Complementary therapies 
  • Diet and nutritional advice 
  • UCLH Prostate Cancer Support Group is held on the 2nd Thursday of each month, from 12.30pm to 2.30pm. You can attend either online or in person. Email uclh.supportandinformation@nhs.net for more information. 
• Prostate Cancer UK 
  0800 074 8383 
  Provides support and information for patients and their families.
• Tackle 
  Provides information, support and access to a network of support groups.
• LGBT Walnut 
  07947 826 853
  A London-based support group for LGBT people affected by prostate cancer.
• Macmillan Cancer Support 
  0808 808 00 00 
  Provides information and support to anyone affected by cancer.
• Cancer Research UK 
  Provides information about prostate cancer and treatments. 
• Infopool. Prostate Cancer Research 
  The infopool has been co-designed with healthcare professionals and patients. Supporting patients and healthcare professionals with a new educational website.
• Squeezy app 
  Support with pelvic floor muscles. Includes exercise videos.
• Your Pelvic Floor 
  Information on pelvic floor exercises.
• 5K Your Way – Move Against Cancer 
  This program invites anyone affected by cancer – patients, loved ones, and cancer care workers—to take part in a 5K Your Way parkrun. Whether you want to walk, jog, run, cheer, or volunteer, you’re welcome to join on the last Saturday of each month.

UCLH cannot accept responsibility for information provided by other organisations.

Prostate Clinical Nurse Specialists (Mon – Fri, 9am to 5pm) 
Contact through their support worker: 
Tel: 07984 391126 
Email: Uclh.prostatecancercns@nhs.net 

Pathway Coordinator for admin queries (for example changing your appointment) (Mon – Fri, 9am to 5pm) 
Tel: 020 3447 9194 
Email: Uclh.prostate.focal@nhs.net

Out of hours, please contact your GP or go to your nearest Emergency Department (A&E).