Proton Therapy For Spinal Tumours

When it comes to treating spinal tumours, precision is paramount. The delicate nature of the spine and its surrounding structures demands a treatment approach that can target cancer cells while minimising damage to healthy tissue. Enter proton therapy, a cutting-edge radiation treatment that's changing the game for patients with spinal tumours. In this comprehensive guide, we'll explore how proton therapy works, its benefits for spinal tumour treatment, and what patients can expect from this innovative approach.1

What is proton therapy?

Proton therapy represents a significant advancement in the field of radiation oncology. Unlike traditional radiation therapy that uses X-rays, proton therapy harnesses the power of positively charged particles called protons to deliver radiation treatment. But what makes protons so special?

The key lies in their physical properties. When accelerated to high speeds, protons can penetrate tissue to a specific depth, depositing most of their energy at a precise point called the Bragg peak. This unique characteristic allows oncologists to target tumours with remarkable accuracy, delivering a high dose of radiation to the cancer cells while significantly reducing exposure to surrounding healthy tissues.2

For patients with spinal tumours, this precision is crucial. The spine houses the spinal cord, a bundle of nerves that's essential for movement and sensation throughout the body. Traditional radiation therapy poses risks of damaging these vital structures, potentially leading to serious side effects. Proton therapy, with its ability to stop at a precise depth, offers a safer alternative, making it an ideal treatment option for sensitive areas like the spine.1

Why choose proton therapy for spinal tumours?

The spine is not just a structural support for our bodies; it's a complex system that plays a critical role in our overall function. When tumours develop in or near the spine, treatment becomes a delicate balancing act between eliminating cancer cells and preserving neurological function. Here's why proton therapy stands out as a treatment option for spinal tumours:

Targeted approach

The hallmark of proton therapy is its ability to deliver a focused beam of radiation. This precision is especially valuable when treating spinal tumours, where vital nerves and structures are nearby. By concentrating the radiation dose on the tumour itself, proton therapy can effectively treat cancer while minimising the risk to surrounding healthy tissue.3

Reduced side effects

One of the most significant advantages of proton therapy is the potential for fewer side effects compared to traditional radiation therapy. Because proton beams can be controlled to stop at the tumour site, there's less radiation exposure to healthy tissues beyond the target area. This can translate to a reduced risk of complications and a better quality of life for patients during and after treatment.2

Effective for complex tumour locations

Spinal tumours often present unique challenges due to their location. They may be situated near critical areas like the spinal cord or other sensitive structures that could be damaged by conventional radiation. Proton therapy's precision allows for the treatment of these complex cases, offering hope to patients who might have limited options with traditional approaches.4

Potential for higher doses

In some cases, the precision of proton therapy allows oncologists to deliver higher doses of radiation to the tumour. This can be particularly beneficial for aggressive or resistant tumours that require more intensive treatment. The ability to escalate the dose without increasing the risk to surrounding tissues can improve the chances of tumour control.1

Types of spinal tumours treated with proton therapy

Proton therapy can be used to treat a variety of spinal tumours, including:

Primary spinal tumours

These are tumours that originate in the spine itself. Examples include:

Chordomas: Rare, slow-growing tumours that develop from remnants of embryonic tissue.

Chondrosarcomas: Cancers that arise from cartilage cells in the spine

Ependymomas: Tumours that form from ependymal cells in the spinal cord

Metastatic spinal tumours

These are cancers that have spread to the spine from other parts of the body. Common primary cancers that can metastasise to the spine include:

Breast cancer

Lung cancer

Prostate cancer

Kidney cancer

The choice to use proton therapy depends on various factors, including the type, size, and location of the tumour, as well as the patient's overall health and treatment history. Your oncologist will work with you to determine if proton therapy is the best option for your specific case.3

Proton therapy process

What to expect

Understanding the treatment process can help alleviate anxiety and prepare patients for what lies ahead. Here's a step-by-step look at what you can expect if you're recommended for proton therapy:

Consultation and imaging

The journey begins with a detailed consultation with a radiation oncologist specialising in proton therapy. They'll review your medical history, perform a physical examination, and discuss your treatment options. If proton therapy is recommended, you'll undergo high-resolution imaging studies such as CT scans, MRIs, or PET scans. These images are crucial for creating a precise treatment plan tailored to your specific tumour.4

Treatment planning

Once the imaging is complete, a team of experts including oncologists, medical physicists, and dosimetrists, work together to develop your treatment plan. Using sophisticated software, they map out the exact dose and direction of the proton beams. This planning phase is meticulous and may take several days to ensure the highest level of precision.2

Simulation and positioning

Before treatment begins, you'll have a simulation session. This involves lying on the treatment table in the exact position you'll be in during therapy. Custom immobilisation devices may be created to ensure you remain perfectly still during treatment. The team may place small marks on your skin to guide positioning for each session.1

Delivery of treatment

When it's time for your actual treatment, you'll lie on the treatment table, and the team will position you using the marks and immobilisation devices from your simulation. The proton therapy machine, called a cyclotron or synchrotron, accelerates protons to high speeds and precisely directs them into your tumour. The treatment itself is painless and typically takes only a few minutes, though positioning may take longer.3

Multiple Sessions

Proton therapy is usually delivered in multiple sessions, known as fractions. The number of sessions can vary depending on your specific treatment plan, but it's common to have treatments five days a week for several weeks. Each session is similar to the first, with careful positioning and a brief treatment time.2

Ongoing care and monitoring

Throughout your treatment course, you'll have regular check-ups with your radiation oncologist to monitor your progress and manage any side effects. These appointments are an excellent opportunity to ask questions and discuss any concerns you may have.4

Benefits of proton therapy for spinal tumours

The advantages of proton therapy for spinal tumour treatment are significant:

Unparalleled precision

The ability to control the depth of the proton beam allows for incredibly precise tumour targeting. This is especially crucial when dealing with spinal tumours, where even small deviations could affect critical structures.1

Sparing healthy tissue

By reducing radiation exposure to healthy tissues surrounding the tumour, proton therapy can help preserve spinal cord function and reduce the risk of long-term complications.2

Fewer side effects

Patients often experience fewer side effects compared to traditional radiation therapy. This can lead to a better quality of life during treatment and faster recovery times.3

Potential for dose escalation

In some cases, the precision of proton therapy allows for higher radiation doses to be delivered to the tumour without increasing risks to nearby healthy tissues. This can be particularly beneficial for stubborn or recurring tumours.4

Option for re-treatment

For patients who have previously undergone radiation therapy, proton therapy may offer a safer option for re-treatment if needed, as it can limit cumulative radiation exposure to healthy tissues.1

Risks and side effects: What patients should know

While proton therapy offers many benefits, patients need to be aware of potential risks and side effects. Although generally considered safer than traditional radiation therapy, proton therapy is still a form of radiation treatment and can cause some side effects:

Fatigue

Many patients experience tiredness during the course of treatment. This is a common side effect of radiation therapy and usually subsides after treatment ends.2

Skin changes

The skin in the treatment area may become red, dry, or irritated. These changes are typically mild and resolve on their own after treatment.3

Temporary hair loss

If the treatment area includes a part of the body with hair, temporary hair loss in that specific area may occur.4

Nerve effects

In rare cases, proton therapy may affect nearby nerves, potentially causing numbness, tingling, or weakness in certain areas. Your medical team will carefully plan your treatment to minimise this risk.1

It's crucial to discuss potential side effects with your healthcare team before starting treatment. They can provide guidance on managing side effects and what to expect during your treatment course.

Who is a candidate for proton therapy?

Proton therapy can be an excellent option for many patients with spinal tumours, but it's not the right choice for everyone. Factors that may make you a good candidate for proton therapy include:

Having a spinal tumour located near sensitive areas, such as the spinal cord or other critical structures

Needing radiation therapy, but having already received the maximum safe dose of traditional radiation to the area

Having a recurrent tumour that requires additional radiation treatment

Being a child or young adult with a spinal tumour, proton therapy can reduce the long-term risks associated with radiation exposure2

The decision to use proton therapy is made on a case-by-case basis. Your oncologist will consider factors such as your overall health, the type and stage of your cancer, and your treatment history to determine if proton therapy is the best option for you.3

Prognosis and follow-up care

The outlook for patients with spinal tumours treated with proton therapy can vary widely depending on factors such as the type of tumour, its size and location, and the patient's overall health. However, many patients experience positive outcomes, with effective tumour control and preservation of neurological function.4

After completing proton therapy, ongoing follow-up care is crucial. This typically involves:

Regular imaging scans to monitor the tumour’s response to treatment and check for any signs of recurrence

Physical examinations to assess neurological function and overall health

Management of any lingering side effects from treatment

Your healthcare team will develop a personalised follow-up plan based on your specific case. It's important to attend all scheduled appointments and report any new symptoms or concerns promptly.1

The future of proton therapy

As technology continues to advance, proton therapy is becoming more widely available and even more precise. Ongoing research is exploring ways to further enhance the effectiveness of proton therapy and expand its applications.

Some areas of development include:

Combining proton therapy with immunotherapy to potentially enhance the body's natural cancer-fighting abilities

Developing more compact proton therapy systems to make the treatment more accessible to a wider range of patients

Refining techniques to account for tumour movement during treatment, allowing for even greater precision2

These advancements hold promise for improving outcomes and quality of life for patients with spinal tumours and other complex cancers.

Summary

Proton therapy represents a significant leap forward in the treatment of spinal tumours. By offering a way to target tumours with unprecedented precision while sparing surrounding healthy tissue, it provides hope for patients facing challenging diagnoses. The potential for reduced side effects and improved quality of life during and after treatment makes proton therapy an attractive option for many.3

However, it's important to remember that every patient's situation is unique. If you or a loved one has been diagnosed with a spinal tumour, the best course of action is to consult with a multidisciplinary team of specialists. They can provide a comprehensive evaluation of your case and help you understand if proton therapy might be right for you.4

As research continues and technology advances, proton therapy is likely to play an increasingly important role in cancer treatment. For patients with spinal tumours, it offers not just a treatment, but a chance at preserving function, reducing side effects, and maintaining quality of life. In the complex world of cancer care, proton therapy shines as a beacon of hope and innovation.1

References

1. Arpit, Chhabra., J.W., Snider., Adam, J., Kole., Lorenzo, Placidi., Adam, L., Holtzman., Robert, H., Press., Chongjin, Wang., Heng, Li., Lin, Haribo., Chengyu, Shi., M, McDonald., Michael, H., Soike., Jun, Zhou., Pouya, Sabouri., Sina, Musashi., Ravel, Colaco., Francesca, Albertini., Charles, B., Simone. 1. Proton Therapy for Spinal Tumours: A Consensus Statement from the Particle Therapy Cooperative Group. International Journal of Radiation Oncology Biology Physics, (2024). Doi: 10.1016/j.ijrobp.2024.04.007
2. Sana, S., Datshi., Alexandra, D., Dreyfuss., Michael, J., Lariviere., Jahan, J., Mohiuddin., Brian, C., Baumann., Jacob, Shaba son., Robert, H., Lustig., Jay, F., Dorsey., Alexander, Lin., Sean, M., Grady., Bert, W., O'Malley., John, Y.K., Lee., Jason, G., Newman., James, M., Schuster., Michelle, Alonso-Basanta. 2. A Prospective Phase I/II Clinical Trial of High-Dose Proton Therapy for Chordomas and Chondrosarcomas. Advances in radiation oncology, (2024). Doi: 10.1016/j.adro.2024.101456
3. Victor, Gabriel, El-Hajj., Abdul, Karim, Ghaith., Harry, Hoang., Ryan, H., Nguyen., N., Saïdi., Stephen, Graepel., Elias, Atallah., Adrian, Elmi‐Treader., Eric, J., Lehrer., Paul, D., Brown., Mohamad, Bidon. 3. Impact of proton versus photon adjuvant radiotherapy on overall survival in the management of skull base and spinal chordomas: a National Cancer Database analysis. Journal of Neurosurgery, (2024). Doi: 10.3171/2024.5. Jns24511
4. Bicentric Treatment Outcomes After Proton Therapy for No myxopapillary High-Grade Spinal Cord Ependymoma in Children. International Journal of Radiation Oncology Biology Physics, (2022). Doi: 10.1016/j.ijrobp.2021.09.030