What Are the Side Effects of Each Prostate Cancer Treatment?

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Medically Approved by Dr Aqua Asif (14/3/25) and Mr Marc Laniado Consultant Urologist GMC: 3343931. (20/3/2026)

At a Glance

Every prostate cancer treatment carries potential side effects — but the type and severity vary significantly depending on which treatment you choose. Radical prostatectomy and radiotherapy carry higher risks of erectile dysfunction and urinary incontinence, while focal therapies such as HIFU (NICE-approved, IPG424) preserve sexual function in over 90% of men and continence in 97% (FTC audit, n=265).

• Erectile dysfunction — the most common concern; affects 30–70% after surgery but over 90% preserve function after focal therapy
• Urinary continence — 97% of focal therapy patients maintain full bladder control (FTC audit, n=265), compared with 80–95% after surgery
• Recovery time — radical surgery requires 4–6 weeks; 85% of focal therapy patients return to work within two weeks
• Bowel and fatigue effects — primarily associated with radiotherapy and chemotherapy, not typically seen with focal therapy
• Your choice matters — side effects depend on the treatment chosen, and discussing all options with a specialist is essential

What Side Effects Can Prostate Cancer Treatment Cause?

Side effects from prostate cancer treatment vary significantly depending on the approach chosen — and understanding these differences can help you make a more informed decision. Radical prostatectomy and radiotherapy carry higher risks of erectile dysfunction and urinary incontinence, while focal therapies such as HIFU and NanoKnife target only the cancerous area, preserving surrounding healthy tissue.

In The Focal Therapy Clinic’s audit of 265 patients, 97% maintained urinary continence and over 90% preserved sexual function after focal therapy. Mr Marc Laniado, Consultant Urological Surgeon (FRCS(Urol), GMC: 3343931), notes: “Side effects depend heavily on the treatment chosen — focal therapy allows us to treat the cancer while protecting the structures that control erections and bladder function.”

Side effects can appear immediately, develop gradually over months, or persist after treatment has finished. Not everyone experiences all of these, and your specialist team will discuss what to expect before you decide on a treatment plan.

How Does Prostate Cancer Treatment Affect Erections?

Erectile dysfunction is the most common concern for men facing prostate cancer treatment, but the risk varies greatly depending on which treatment you choose. After radical prostatectomy, 30–70% of men experience lasting erectile problems. In The Focal Therapy Clinic’s audit of 265 patients, over 90% of men with normal pre-treatment erections preserved sexual function after focal therapy.

Mr Marc Laniado, Consultant Urological Surgeon (FRCS(Urol), GMC: 3343931), explains: “If you had completely normal erections before treatment, most men find that their erections return within a few months after focal therapy. By one year, most men find their erections are normal or close to normal.”

How each treatment affects erections:

• Radical prostatectomy — can directly damage the nerves controlling erections; 30–70% of men experience lasting erectile dysfunction
• Radiotherapy — may cause gradual changes in erectile function over months to years as blood vessels are affected
• Hormone therapy — lowers testosterone, reducing sex drive and affecting erections for the duration of treatment
• Focal therapy (HIFU/NanoKnife) — targets only the cancerous area, preserving the nerves; over 90% maintain sexual function (FTC audit, n=265)

Timeframe: Some men notice an immediate effect after surgery, while radiotherapy changes develop more gradually. After focal therapy, temporary changes typically resolve within 6–12 months.

Management: Medications such as sildenafil (Viagra) and tadalafil (Cialis), vacuum devices, penile injections, or implants can all help. Pelvic floor exercises and early rehabilitation programmes support recovery. Couples counselling may also help address the emotional and relationship impact.

Will I Have Bladder Control Problems After Prostate Cancer Treatment?

Urinary incontinence is a significant concern, but the risk depends heavily on your treatment. After radical prostatectomy, 5–20% of men experience ongoing leakage requiring pads at one year. In The Focal Therapy Clinic’s audit of 265 patients, less than 2% experienced urinary incontinence after focal therapy — meaning 97% maintained full bladder control without pads.

How each treatment affects bladder control:

• Radical prostatectomy — can weaken or damage the sphincter muscles controlling urine flow; 5–20% have significant ongoing leakage
• Radiotherapy — may irritate the bladder, causing urgency, frequency, and nighttime urination during and after treatment
• Focal therapy (HIFU/NanoKnife) — 97% maintain full continence (FTC audit, n=265); bladder control is rarely affected

Timeframe: After surgery, leakage is often immediate but can improve over months. Radiotherapy-related bladder irritation typically occurs during or shortly after treatment. After focal therapy, Mr Marc Laniado notes that “bladder control is rarely affected — most men do not experience leakage when coughing or straining.”

Management: Pelvic floor exercises (Kegel exercises), bladder training, and medication can help. Continence products provide reassurance until control improves. In persistent cases, an artificial urinary sphincter may be an option.

Does Prostate Cancer Treatment Cause Fatigue?

Fatigue is common during and after radiotherapy, chemotherapy, and hormone therapy for prostate cancer, and can persist for weeks to months. Focal therapy patients typically experience less prolonged fatigue — at The Focal Therapy Clinic, 85% of men return to work within two weeks of their procedure, as the outpatient treatment avoids the systemic effects of radiation or chemotherapy.

Timeframe: Radiotherapy and chemotherapy fatigue can start early and last for weeks or months. Hormone therapy fatigue may continue for the duration of treatment. After focal therapy, most men resume normal activities within one to two weeks.

Management: Gentle exercise (such as short walks), balanced meals, and regular rest breaks can help. Counselling or support groups may also be beneficial, as fatigue can affect both physical and emotional wellbeing.

Can Prostate Cancer Treatment Cause Nausea?

Nausea and vomiting primarily affect men receiving chemotherapy for prostate cancer, though some radiotherapy patients experience mild nausea. Focal therapy procedures such as HIFU (NICE-approved, IPG424) and NanoKnife IRE (IPG768) do not typically cause nausea, as they are localised, day-case treatments performed under general anaesthetic at The Focal Therapy Clinic.

Timeframe: Chemotherapy-related nausea often begins during or shortly after sessions and can last for a few days.

Management: Anti-sickness medications (antiemetics) are commonly prescribed and are very effective. Staying hydrated, eating small light meals, and using relaxation techniques may also help.

Can Prostate Cancer Treatment Cause Bowel Problems?

Bowel changes — including diarrhoea, urgency, and loose stools — are a recognised side effect of radiotherapy for prostate cancer. As Dr Christos Mikropoulos, Consultant Clinical Oncologist (FRCR, GMC: 4692210) at The Focal Therapy Clinic explains, these effects occur because the prostate sits close to the bladder and bowel, and radiation can cause inflammation in these neighbouring organs.

Focal therapy carries an extremely low risk of bowel complications. Because HIFU and NanoKnife target only the prostate tissue, the bowel is not exposed to treatment energy. The risk of rectal injury is negligible unless the patient has had prior radiotherapy.

Timeframe: Radiotherapy-related bowel changes may occur during treatment or shortly afterwards, and can sometimes become long-term if the bowel lining is affected.

Management: Adjusting your diet (changing fibre intake), anti-diarrhoeal or laxative medications (as advised by your doctor), and staying well-hydrated can help. If symptoms persist, inform your medical team — specialist dietary advice or further intervention may be needed.

How Does Treatment Affect Fertility and Ejaculation?

Changes to ejaculation and fertility are common after prostate cancer treatment, but the extent depends on the treatment chosen. After radical prostatectomy, natural conception is no longer possible. After focal therapy, ejaculation may be reduced or absent, but orgasmic sensation is preserved — and fertility impact is typically less severe than with surgery or radiotherapy.

Ejaculation

• Radical prostatectomy — the prostate and seminal vesicles are removed, resulting in “dry orgasm” (anejaculation). Orgasmic sensation remains, but no semen is released. Natural conception is no longer possible.
• Radiotherapy or hormone therapy — can reduce the volume of ejaculate and sperm count. Radiation may cause scarring that disrupts semen production over time.
• Focal therapy (HIFU/NanoKnife) — ejaculation may be reduced or absent, but orgasmic sensation is preserved. Mr Marc Laniado (FRCS(Urol), GMC: 3343931) notes that this is generally well-tolerated by patients.

Read more: Does Prostate Cancer Stop You from Ejaculating?

Fertility

• Short-term and long-term effects — fertility can be temporarily reduced or permanently affected, depending on the treatment type and dose.
• Sperm banking — if fathering children in the future is a concern, storing sperm before treatment is strongly recommended. This is discussed during pre-treatment counselling at The Focal Therapy Clinic.
• Assisted reproduction — techniques like IVF (in vitro fertilisation) may still be possible if sperm has been banked or some sperm remains in the ejaculate.

Can Prostate Cancer Treatment Affect Your Mental Health?

A prostate cancer diagnosis and its treatments can be emotionally challenging, leading to stress, anxiety, and sometimes depression. Hormone therapy in particular can cause mood swings and low mood due to testosterone reduction. At The Focal Therapy Clinic, your consultant team discusses the emotional aspects of treatment as part of your care — because mental wellbeing matters as much as physical outcomes.

Timeframe: Emotional changes can happen at any point — from initial diagnosis through treatment and into recovery. Men undergoing hormone therapy may experience mood changes for the duration of treatment.

Management: Talk openly with family, friends, or a counsellor about how you are feeling. Support groups help you connect with others who have been through similar experiences. If needed, your doctor may recommend medication for depression or anxiety. Choosing a treatment with fewer physical side effects — such as focal therapy, which preserves continence and sexual function — can also reduce the psychological burden of treatment.

What Other Side Effects Should You Know About?

Several additional side effects are associated primarily with hormone therapy (androgen deprivation therapy), which is used alongside some prostate cancer treatments. Focal therapy at The Focal Therapy Clinic does not typically require accompanying hormone therapy, so these effects are generally not a concern for focal therapy patients.

• Hot flushes — commonly associated with hormone therapy. Lifestyle adjustments such as dressing in layers and avoiding caffeine or spicy foods can help.
• Weight gain and muscle loss — hormone therapy lowers testosterone, altering body composition. Strength training and exercise programmes help maintain muscle mass and a healthy weight.
• Bone thinning (osteoporosis) — a potential effect of long-term hormone therapy. Weight-bearing exercise and certain medications can help maintain bone density.

Which Prostate Cancer Treatment Has the Least Side Effects?

Focal therapies — specifically HIFU (High-Intensity Focused Ultrasound), approved by NICE under IPG424, and NanoKnife IRE (Irreversible Electroporation), approved under IPG768 — have the lowest side-effect profile of any active prostate cancer treatment. By targeting only the cancerous area of the prostate, these treatments preserve surrounding healthy tissue, nerves, and blood supply.

In The Focal Therapy Clinic’s audit of 265 patients, focal therapy outcomes demonstrated significantly fewer side effects than traditional approaches:

Source: FTC one-year outcome audit (n=265) and published literature

“Not every patient is suitable for focal therapy, and we’re transparent about that. We assess every referral carefully with mpMRI and targeted biopsy before recommending treatment.”

The best treatment decision balances the stage and grade of your cancer, your overall health, and your personal priorities regarding quality of life. It is essential to discuss all options — including focal therapy — with a specialist team before deciding.

Frequently Asked Questions

Which prostate cancer treatment has the least side effects?
Focal therapies (like HIFU and NanoKnife) aim to minimise side effects by treating only the affected part of the prostate, but they’re not suitable for all men. All treatments have potential side effects. The best choice depends on your individual situation and should be discussed thoroughly with your doctor.

References

1. Cancer Research UK (n.d.). Treatment for prostate cancer. Retrieved from https://www.cancerresearchuk.org/about-cancer/prostate-cancer/treatment
2. Prostate Cancer UK (n.d.). Prostate cancer treatments. Retrived from https://prostatecanceruk.org/prostate-information-and-support/treatments?category=
3. Chen RC, Rumble RB, Loblaw DA, et al. Active Surveillance for the Management of Localized Prostate Cancer (Cancer Care Ontario Guideline): American Society of Clinical Oncology Clinical Practice Guideline Endorsement. J Clin Oncol. 2016;34(18):2182-2190. doi:10.1200/JCO.2015.65.7759

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