Radiation Therapy Vs Proton Therapy: Everything You Need To Know

What Is Radiation Therapy?

Radiation therapy, also known as radiotherapy, is a medical treatment that uses high doses of radiation to kill cancer cells and shrink tumours. This treatment works by damaging the DNA within cancer cells, which inhibits their ability to replicate and grow. 

Over time, the damaged cancer cells die off, and the body naturally eliminates them. Radiation therapy can be administered externally, using machines like linear accelerators to direct radiation beams at the tumour, or internally, through a process known as brachytherapy, where radioactive materials are placed inside or near the tumour.

Differences between radiation therapy vs proton therapy

What Is Proton Therapy?

Proton therapy is an advanced form of radiation therapy that uses protons rather than traditional X-rays (photons) to treat cancer. The primary advantage of proton therapy lies in its precision; protons can be controlled to release their maximum energy directly at the tumour site, thereby minimising damage to surrounding healthy tissues. 

This precision allows for higher doses of radiation to be safely delivered to the tumour, potentially improving treatment outcomes and reducing side effects. Studies have demonstrated the effectiveness and safety of proton therapy. 

For example, research has shown that proton therapy can significantly reduce radiation doses to normal tissues, which is particularly beneficial for patients with lung cancer and those undergoing treatment for breast cancer to reduce cardiac risks. Furthermore, proton therapy has been associated with lower rates of severe toxicities compared to traditional radiation therapy, as observed in a study involving head and neck cancer patients.

What Are The Success Rate And Efficacy Of Both Therapies?

Radiation therapy is a widely used and an effective treatment for various cancers, often used alone or in combination with surgery and chemotherapy. Studies have shown that radiation therapy is effective in local tumour control and overall survival across many cancer types. 

For example, in a study on non-small-cell lung cancer, intensity-modulated radiation therapy (IMRT) demonstrated a 5-year survival rate of around 26%, with significant tumour control rates.

Conventional radiation therapy, while effective, often results in higher doses of radiation to surrounding healthy tissues, leading to side effects such as skin irritation, fatigue, and damage to nearby organs. However, the overall success in tumour reduction and management makes it a cornerstone in cancer therapy.

But what about proton therapy? 

Proton therapy is known for its precision in targeting tumours, reducing damage to surrounding healthy tissues. This precision translates into lower rates of acute and long-term side effects. 

For instance, proton therapy has shown high efficacy in treating paediatric brain tumours and certain types of head and neck cancers, achieving excellent tumour control and survival rates. In paediatric intracranial ependymoma, proton therapy provided a 3-year local control rate of 85% and overall survival rate of 90%.

Proton therapy is associated with fewer side effects compared to traditional radiation therapy due to its ability to spare normal tissues from high doses of radiation. For example, in treating breast cancer, proton therapy has demonstrated significantly lower cardiac toxicity compared to photon therapy, while maintaining similar levels of cancer control.

Key Difference Between Radiation Therapy & Proton Therapy

The key differences between radiation therapy and proton therapy revolve around the type of radiation used, precision of targeting, and the associated side effects.

Precision and Side Effects

Radiation Therapy
While it may be effective, the nature of photon beams means they can impact surrounding healthy tissues, leading to higher rates of side effects such as skin irritation, fatigue, and damage to nearby organs.

Proton Therapy
Offers enhanced precision, significantly reducing radiation doses to normal tissues. This precision leads to fewer side effects and lower risks of long-term complications. Studies have shown that proton therapy reduces radiation exposure to critical organs like the heart in breast cancer treatments, thus lowering the risk of cardiac issues. 

Cost and Accessibility

Radiation Therapy
Generally more accessible and less expensive due to the lower cost of equipment and infrastructure. It is available in many hospitals and cancer treatment centres worldwide.

Proton Therapy
Requires significant investment in specialised facilities, making it more expensive and less accessible. However, for certain cancers, the cost-effectiveness can be justified by the reduced side effects and improved quality of life. For instance, proton therapy can be cost-effective for treating specific cancers like paediatric brain tumours and certain types of breast cancer if appropriate risk groups are chosen.

Clinical Outcomes

Radiation Therapy
Effective for a wide range of cancers, but the higher dose to surrounding tissues can lead to increased acute and long-term side effects. Despite this, it remains a cornerstone of cancer treatment.

Proton Therapy
Particularly beneficial for paediatric cancers and tumours located near critical structures such as the brain, spine, and heart. It has been associated with improved survival rates and reduced treatment-related toxicity. For example, in treating head and neck cancers, proton therapy has shown to significantly reduce toxicity compared to intensity-modulated radiation therapy (IMRT).

What Are The Conditions That Require Proton Therapy & Radiation Therapy?

Radiation Therapy

Radiation therapy is commonly used for a wide variety of cancers. Its application depends on the cancer type, stage, and location. Here are some specific conditions where radiation therapy is typically utilised:

Breast Cancer
Radiation therapy is a standard treatment for breast cancer, often used after surgery to eliminate any remaining cancer cells. Studies have shown it reduces the risk of recurrence and improves overall survival rates.

Non-Small Cell Lung Cancer (NSCLC)
Radiation therapy is often used either as a primary treatment for inoperable tumours or as an adjunct to surgery and chemotherapy. A study indicated significant improvements in overall survival when proton therapy was used compared to traditional photon therapy for NSCLC.

Prostate Cancer
Radiation therapy is a common treatment for prostate cancer, particularly for patients who are not candidates for surgery. Proton therapy has been shown to be effective, with high disease-free survival rates and minimal morbidity.

Head and Neck Cancers
Radiation therapy is crucial for treating head and neck cancers, either alone or in combination with surgery and chemotherapy. The precision of proton therapy helps in sparing critical structures and reducing side effects.

Proton Therapy

Proton therapy is especially beneficial for tumours located near critical structures and in paediatric patients where minimising long-term side effects is crucial. Here are some conditions where proton therapy is particularly advantageous:

Paediatric Brain Tumours
Proton therapy is preferred for treating paediatric brain tumours due to its precision in targeting the tumour while sparing healthy brain tissue. This reduces the risk of long-term cognitive and developmental issues.

Spinal and Base of Skull Tumours
Tumours in the spine or at the base of the skull are challenging to treat due to their proximity to critical nerves and brain structures. Proton therapy’s precision makes it an ideal choice for these locations.

Liver Cancer
Proton therapy can be particularly effective for hepatocellular carcinoma, where it can target the tumour precisely while sparing healthy liver tissue, reducing the risk of complications and improving overall survival rates.

Prostate Cancer

Proton therapy in alternate to radiation therapy, is also used for prostate cancer, particularly in patients who need to minimise radiation exposure to surrounding organs like the bladder and rectum. It has been shown to offer excellent disease control with reduced side effects.

Weighing The Pros And Cons Of Choosing One Form Of Therapy

In conclusion, both radiation therapy and proton therapy play critical roles in the treatment of various cancers, each offering unique benefits and drawbacks. Radiation therapy, with its broad accessibility and effectiveness, remains a cornerstone in cancer treatment. 

However, its higher impact on surrounding healthy tissues can lead to increased side effects. On the other hand, proton therapy’s precision significantly reduces radiation exposure to normal tissues, resulting in fewer side effects and potentially better outcomes for certain cancers, particularly those in paediatric patients and tumours near critical structures. 

While the cost and accessibility of proton therapy remain challenges, its advantages in specific clinical scenarios justify its use. The choice between these therapies should be guided by the individual patient’s needs, tumour characteristics, and the potential benefits of each treatment modality. 

By understanding the distinctions and applications of these therapies, patients and healthcare providers can make more informed decisions to achieve the best possible outcomes in cancer treatment.

Written by

Priyom holds a Ph.D. in Plant Biology and Biotechnology from the University of Madras, India. She is an active researcher and an experienced science writer. Priyom has also co-authored several original research articles that have been published in reputed peer-reviewed journals. She is also an avid reader and an amateur photographer.

Written by

Priyom holds a Ph.D. in Plant Biology and Biotechnology from the University of Madras, India. She is an active researcher and an experienced science writer. Priyom has also co-authored several original research articles that have been published in reputed peer-reviewed journals. She is also an avid reader and an amateur photographer.

Latest News

Suggested Reading