Prostate cancer is the most common cancer among men. Radiotherapy is a key treatment option for it, and for many years, radiotherapy has relied on CT scans to guide treatment. While effective, this method has limits when it comes to clearly seeing the prostate and protecting nearby organs.
A new approach called MRI-guided radiotherapy is changing that. Doctors can use MRI scans during treatment to deliver radiation more accurately. This helps reduce side effects and improves patients’ quality of life.
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What is MRI-Guided Radiotherapy?
MRI-guided radiotherapy is one of the most advanced approaches in modern cancer care. It brings together two technologies that work best in combination:
- Magnetic resonance imaging (MRI) provides high-resolution images of soft tissues such as the prostate, bladder, and rectum. Unlike CT scans, MRI shows these organs with much more detail, making it easier to identify and monitor the tumour.
- Radiotherapy – delivers beams of radiation that destroy cancer cells by damaging their DNA, one of the main treatments for prostate cancer and radiotherapy care.
When used together, the result is known as MRI-linac radiotherapy. This system combines an MRI scanner with a linear accelerator (the radiotherapy machine).
The advantage is that treatment is no longer based only on scans taken during the initial planning stage. Instead, MRI radiotherapy treatment planning happens in real time, allowing doctors to:
- See the prostate and nearby tissues clearly during each session.
- Adapt treatment instantly if the prostate shifts because of bladder filling or bowel movement.
- Reduce the size of safety margins that were previously needed in standard radiotherapy for prostate cancer. These margins often exposed healthy organs to radiation, which increased side effects.
- Deliver radiation with greater accuracy, improving tumour control and patient outcomes.
This method is particularly valuable in radiotherapy for prostate cancer, where precision is critical. The prostate gland is located next to the bladder, rectum, and important nerves, so even small inaccuracies can affect urinary function, bowel health, or sexual wellbeing.
By using MRI in radiotherapy planning, doctors can protect these sensitive structures while still targeting the tumour effectively. This makes MRI-guided radiotherapy one of the safest and most promising ways to treat prostate cancer today.
MRI in Radiotherapy Planning
Planning is one of the most important steps in cancer care, especially for men receiving radiotherapy for prostate cancer. The accuracy of the plan determines how well the tumour is controlled and how well healthy organs are protected.
MRI in radiotherapy planning has transformed this process. In the past, treatment was designed mainly with CT scans. While CT is useful, it does not show soft tissues as clearly as MRI. As a result, doctors often had to make educated guesses about the exact position of the prostate and its relationship to nearby organs.
Why prostate motion matters
The prostate does not stay fixed in place. It can move naturally due to:
- Bladder filling – as urine builds up, the bladder pushes against the prostate.
- Bowel movements or gas – which can shift the prostate in different directions.
- Normal body changes – even subtle movements or breathing can make a difference.
With CT-based planning, doctors had to create wide “safety margins” around the prostate to make sure the tumour was always covered. Unfortunately, these margins often expose parts of the bladder, rectum, and surrounding tissue to radiation, increasing the risk of urinary, bowel, or sexual side effects.
How MRI radiotherapy treatment planning changes things
With MRI-guided radiotherapy treatment planning, this problem is solved:
- Each treatment session begins with a new MRI scan, providing a fresh and accurate picture of the prostate.
- If the prostate has shifted, the plan is updated immediately while the patient is still on the table.
- Radiation is delivered only where it is needed, without unnecessarily affecting nearby healthy tissue.
This adaptive approach means that:
- The tumour is consistently targeted with high precision.
- Healthy organs such as the bladder and rectum are protected session after session.
- Patients experience fewer long-term side effects and a better quality of life after treatment.
A new standard of care
Dr Carla Perna explains to her patients that this adaptive planning is one of the biggest advantages of MRI radiotherapy. Instead of working with a “one-size-fits-all” plan designed weeks earlier, every treatment is personalised in real time. This ability to adapt daily is why MRI guidance is increasingly considered the future standard in prostate cancer radiotherapy.
If you’re noticing early prostate cancer symptoms, speaking with a specialist can help you understand whether MRI-guided radiotherapy may be right for you.
Benefits of MRI-Guided Radiotherapy for Prostate Cancer
The advantages of MRI-guided radiotherapy for prostate cancer are clear. Patients and doctors highlight four main benefits:
1. Greater Precision
- MRI scans provide much sharper images than CT scans.
- Doctors can see the prostate, lymph nodes, and nearby organs in detail.
- This improves tumour control while avoiding unnecessary radiation to healthy structures.
2. Fewer Side Effects
Because of its precision, MRI radiotherapy lowers the risk of:
- Urinary problems (frequency, urgency, discomfort).
- Bowel issues (diarrhoea, bleeding, rectal irritation).
- Sexual side effects (erectile dysfunction due to nerve damage).
This directly improves the quality of life for men undergoing treatment.
3. Adaptive Treatment
- MRI allows treatment to be adjusted daily based on the patient’s anatomy.
- If the prostate shifts, the treatment adapts instantly.
- This is known as adaptive MRI radiotherapy, and it personalises care for every session.
4. Backed by Clinical Evidence
The MIRAGE trial – a major study comparing MRI-guided with CT-guided radiotherapy found:
- Lower urinary side effects (24% with MRI vs 43% with CT).
- Fewer bowel complications (0% with MRI vs 10% with CT).
- Reduced long-term toxicity (urinary: 27% vs 51%; bowel: 1.4% vs 9.5%).
MRI-guided radiotherapy for prostate cancer is more than just an idea. It’s a confirmed step forward in cancer treatment.
Does Radiotherapy Cure Prostate Cancer?
A common question men ask is, “Does radiotherapy cure prostate cancer?”
For men whose cancer is found while it is still localised (confined to the prostate), radiotherapy is often a curative option. Large studies show that the long-term success of prostate cancer and radiotherapy is very similar to that of surgery. In fact, in many cases, radiotherapy is preferred because:
- It is non-invasive, meaning there is no surgery or hospital recovery.
- The treatment is usually done on an outpatient basis, so men can continue with their normal routines.
- It can be combined with hormone therapy if needed, making it very flexible.
Thanks to new advances in MRI radiotherapy treatment planning, cure rates are higher than ever, while side effects are fewer. The MRI scans allow doctors to see the prostate clearly, adapt the plan daily, and ensure that radiation is always directed at the tumour and not healthy tissues. It’s important to understand that while no cancer treatment can guarantee success in 100% of cases, for many men with early-stage disease, radiotherapy can cure prostate cancer. MRI guidance makes this approach not only effective but also safer, reducing risks to the bladder, rectum, and nerves that control sexual function.
Better Precision, Better Outcomes
MRI-guided radiotherapy for prostate cancer is one of the most exciting advances in modern cancer care. By combining the clarity of MRI with the precision of radiotherapy, doctors can target tumours more accurately, adapt treatment in real time, and better protect healthy tissue.
For men asking, “Can radiotherapy cure prostate cancer?”, the answer is increasingly positive. With MRI in radiotherapy planning, the treatment is not only effective but also safer, more comfortable, and easier to tolerate than older methods.
As more centres adopt this technology, patients have access to treatment that offers better cancer control, fewer side effects, and improved quality of life after therapy.
If you or a loved one has been diagnosed with prostate cancer, now is the time to discuss whether MRI-guided radiotherapy is the right choice for you. Speaking with specialists like Dr Carla Perna can help you understand your options – you can contact us today to arrange a consultation.
FAQs
What is MRI-guided radiotherapy?
MRI-guided radiotherapy is a modern form of cancer treatment where magnetic resonance imaging (MRI) is used during every radiotherapy session. Unlike standard imaging, MRI provides clear pictures of the prostate and surrounding soft tissue, which allows doctors to see exactly where the tumour is at each moment. This means radiation can be delivered with much higher precision and accuracy. At Dr Carla Perna’s clinic, this advanced technology is offered to men with prostate cancer who want treatment that is both effective and designed to reduce unnecessary side effects.
How is MRI radiotherapy different from standard prostate cancer radiotherapy?
Standard prostate cancer radiotherapy usually relies on CT scans, which are good at showing bones but not soft tissues. The prostate can move slightly from day to day, depending on bladder filling or bowel changes, and CT scans cannot always account for this. MRI radiotherapy, on the other hand, shows the prostate and nearby organs in much sharper detail, making it possible to adapt treatment in real time if the prostate has shifted. Dr Carla Perna explains to her patients that this is one of the biggest differences — MRI guidance allows her team to adjust on the spot, which greatly reduces the chance of healthy organs like the bladder and rectum receiving unnecessary radiation.
Can radiotherapy cure prostate cancer?
For many men with localised disease, radiotherapy can be curative. Large clinical trials have shown that outcomes with radiotherapy are often comparable to surgery. With MRI radiotherapy treatment planning, the chances of a cure are even stronger because the treatment is delivered more accurately and consistently. Dr Perna advises her patients that while no treatment is guaranteed for everyone, MRI-guided radiotherapy significantly increases the likelihood of long-term control and, in many cases, cure.
What are the side effects of prostate cancer and radiotherapy?
All types of radiotherapy may cause some side effects, but MRI guidance helps reduce their severity. Common side effects include changes in urinary habits (such as frequency or urgency), mild bowel irritation, erectile dysfunction, and in some cases hot flashes, especially if hormone therapy is also part of the treatment plan. Dr Perna emphasises that because MRI allows her team to avoid healthy tissues, these side effects are often milder and less disruptive to daily life compared with traditional radiotherapy.
Is MRI-guided radiotherapy widely available?
MRI-guided radiotherapy is a relatively new technology, so it is not yet available in every hospital. However, it is offered at advanced cancer centres across the UK and Europe, including through Dr Carla Perna’s practice. She is one of the specialists bringing this innovative treatment to patients, making it possible for more men to access the benefits of MRI-guided care.
Which cancers can be treated with MRI-guided radiotherapy?
While prostate cancer is currently one of the main conditions treated with MRI guidance, this technology is also being studied and used for other cancers, such as pancreatic, liver, cervical, and lung cancers. Dr Perna notes that MRI-guided radiotherapy is especially valuable in cancers where tumours are close to delicate organs and accuracy is essential.
What are the main advantages of MRI-guided treatment?
The main advantages are precision, safety, and adaptability. MRI-guided treatment means radiation beams can be targeted directly at the tumour while avoiding healthy tissue, side effects are significantly reduced, and the treatment can adapt each day based on changes in the body. According to Dr Perna, this combination makes MRI-guided radiotherapy one of the safest and most advanced treatment options currently available.
Are there any risks or side effects with MRI-guided radiotherapy?
As with all cancer treatments, there are still some risks and side effects, but MRI guidance minimises them. Patients may still experience fatigue, minor urinary changes, or temporary bowel discomfort, but these are generally less severe than with CT-guided treatment. Dr Perna explains that because her team can see the prostate in real time, they can stop or adjust treatment if the organ moves, further lowering the chance of complications.
How many sessions are needed for MRI-guided radiotherapy?
The number of sessions depends on the treatment plan. Traditional radiotherapy can require 20-45 daily sessions, but with advanced techniques like MRI-guided stereotactic body radiotherapy (SBRT), treatment may be completed in as few as five sessions. Dr Perna works closely with each patient to decide which approach is most suitable, based on their cancer stage and overall health.
Can MRI-guided radiotherapy be used for re-irradiation?
Yes. In some cases, patients who have already received radiotherapy may require treatment again if their cancer returns. Because MRI guidance is so precise, it can allow doctors like Dr Perna to retreat an area while keeping surrounding organs safe. This offers new hope for patients who might not have been eligible for additional radiation with older methods.
References:
Kishan, A. U., Ma, T. M., Lamb, J., Casado, M., Wang, X., Sun, Y., … Steinberg, M. L. (2023). Magnetic resonance imaging-guided vs computed tomography-guided stereotactic body radiotherapy for prostate cancer: The MIRAGE randomized clinical trial. JAMA Oncology, 9(3), 365-373. https://doi.org/10.1001/jamaoncol.2022.6558
Kishan, A. U., Ma, T. M., Lamb, J. M., Casado, M., Wang, X., Sun, Y., … Steinberg, M. L. (2025). Magnetic resonance imaging versus computed tomography guidance for stereotactic body radiotherapy in prostate cancer: 2-year outcomes from the MIRAGE randomized clinical trial. European Urology, 87(6), 622-625. https://doi.org/10.1016/j.eururo.2025.02.012
UCLA Health. (2025, March 28). MRI-guided radiation therapy reduces long-term side effects in prostate cancer treatment. UCLA Health News Releases. https://www.uclahealth.org/news/release/mri-guided-radiation-therapy-reduces-long-term-side-effects
Nair, R., Kishan, A. U., Ma, T. M., Lamb, J., & Steinberg, M. L. (2024). Patient-reported outcomes following magnetic resonance-guided stereotactic body radiotherapy for prostate cancer. International Journal of Radiation Oncology • Biology • Physics, 110(5), 1409-1418. https://doi.org/10.1016/j.ijrobp.2024.02.018
Michalski, J. M., Xu, Y., Wang, X., … Kishan, A. U. (2022). Reduced long-term toxicity with MRI-guided radiotherapy for prostate cancer: Results from the MIRAGE trial. Cancer, 128(21), 3813-3821. https://doi.org/10.1002/cncr.35762
