Patient information

Proton therapy is the most precise form of external radiotherapy.

More specifically, proton therapy is the most accurate and precise form of external radiotherapy. Unlike conventional radiotherapy, its lower toxicity means increased doses can be applied to the tumor when necessary, and therefore greater local control of the cancer can be achieved with minimal unnecessary exposure of normal tissues to scatter radiation.

The greater precision and reduced toxicity achieved through treatment with this technology makes proton therapy particularly suitable for the oncological treatment of children and elderly adults with cancer affecting areas that are especially sensitive to irradiation, such as the brain, spinal cord or eyes, mucous membranes and germ cells, among others.

Proton therapy is based on a different type of radiation to conventional radiation therapy.

Whereas conventional radiotherapy is based on a high-energy beam of X-rays (photons) or electrons, proton therapy uses a beam of accelerated high-energy particles (protons), which enable the radiation deposit and its antitumor effect on the cancer to be directed more precisely.

This is due to the physical characteristics of the accelerated protons because, due to their mass, their trajectory is not affected when they penetrate the patient, which means that most of their energy will be deposited upon final impact, which is set up to occur inside the tumor, in a personalized fashion.

When protons reach cancer cells, they transfer energy to electrons in the intracellular molecules, causing a series of interactions, or ionizing events, that damage all the ionized molecules, especially the DNA, which governs cell life and reproduction. Cancer cells with intensely ionized molecules are rendered nonviable and die because they can no longer divide (reproductive damage) or recover, and the residual tissue is replaced by normal cells with reparative properties.

Proton therapy is based on a different type of radiation from conventional radiation therapy.

Whereas conventional therapy is based on beams of photons and electrons, proton therapy uses a high-energy, multi-energy-level beam of heavy accelerated particles (protons), enabling radiation to be deposited in the tumor and directed more precisely, therefore significantly reducing damage to nearby healthy tissues.

This is due to the protons’ physical characteristics, as, given their mass, their trajectory is not altered when they penetrate the patient in the direction of the area affected by cancer, with a narrow braking gradient: this means they can release most of their energy inside the tumor.

Therefore, there are two major differences: the biological antitumor effect is greater due to the intensity of ionization produced, and the unnecessary irradiation of normal tissues is avoided due to the absence of scatter irradiation and the high precision and narrow braking gradient of the therapy.

In many cases, yes. Proton therapy can be used in combination with chemotherapy, as a complementary treatment to surgery and in combination with standard radiation treatment (to intensify radiation-resistant areas).

It may also be a treatment option in cases where a tumor has recurred after previous treatment with traditional radiotherapy and cannot be treated again with conventional radiation due to the limited tolerance of normal tissue critical to maintaining the patient’s quality of life.

Yes. No oncological treatment—neither radiation nor pharmacological—is harmless. The side effects associated with proton therapy are multifactorial and depend on the interaction between the irradiation itself on tissues and the patient’s general condition, as well as the tissues exposed to radiation.

Proton therapy is less toxic than other external radiotherapy alternatives. The expected toxicity of each radiotherapy treatment is individualized and highly predictable. Each patient is given detailed information in advance before informed consent is sought from the patient.

Proton therapy minimizes the toxicity patients suffer and is one of its key established advantages.

Hair loss occurs only when the cranial area is treated. Radiation-induced nausea and vomiting occur on an exceptional basis in extreme cases involving proton therapy in the abdomen or pelvis, and in cases involving extremely large volumes.

Some patients treated with proton therapy also receive chemotherapy and may suffer from hair loss or nausea for this reason.

Proton therapy is generally the treatment of choice for tumors treatable with external radiation therapy, because it is the form of treatment that best preserves healthy tissue and reduces adverse effects on growing structures.

Pediatric cancer patients usually survive their disease. Adverse secondary effects must be prevented, and any resultant disability as adults must be minimized. The dosimetric benefit makes proton therapy the technique of choice in pediatric radiotherapy.

Yes, although proton therapy is more effective in treating localized cancer, particularly tumors that have not spread to other parts of the body.

If the tumor has spread (metastasized), proton therapy may be an option, depending on the number of metastases and other factors (oligometastatic or oligo-recurrent disease).

Hence, it is important to have a multi-professional and interdisciplinary team integrating specialized medical knowledge and able to determine the best-possible therapy for each case on a personalized basis.

Proton therapy is considered the therapy of choice for tumors near critically sensitive organs such as the heart, lungs, gastrointestinal mucosa and genitourinary system, or structures such as the brain and spinal cord. However, the current evidence is constantly changing.

The application of proton therapy for other tumors and clinical indications is being studied. It is estimated that 15% of patients undergoing radiotherapy treatment could be treated with proton therapy, i.e. around 700 people in Spain every year.

At the Clínica Universidad de Navarra, we have a multidisciplinary team composed of professionals from a range of different fields who lead the Proton Therapy Unit.

This team is made up of experts, notably including specialists responsible for patient care, radiotherapy oncologists, radio-physicists, biomedical engineers, nurses, technicians, dosimetrists and all the medical and surgical specialties involved in the oncology areas of the Navarre University Cancer Center.

There is extremely close collaboration with Pediatric Oncology, Medical Oncology, Hematology, Anesthesia, Diagnostic Imaging and Pathological Anatomy.

The inpatient location ensures advancement and innovation in proton therapy, synchronized with highly specialized medical progress.

No. The first case of a patient receiving proton therapy was recorded over 50 years ago and, to date, more than 100,000 people worldwide have received proton therapy at centers in Europe, the United States and Asia.

Yes. The medical community continues to conduct research studies on proton therapy.

Leading cancer treatment institutions such as the Mayo Clinic, St. Jude Children’s Research Hospital, the MD Anderson Cancer Center and John Hopkins are part of a research association that our Proton Therapy Unit also belongs to, with multiple prospective clinical trials underway to help find improvements in cancer treatment using this therapy.

Given the academic nature of the Navarre University Hospital, research is one of our strategic pillars. We take part in clinical trials and generate clinical and translational research projects in conjunction with the Center for Applied Medical Research (CIMA).

In the field of proton therapy, the most advanced technology relates to the synchrotron, an advanced particle accelerator that generates a “cleaner” beam.

The synchrotron enables the release of a proton beam with the specific energy level needed for each patient’s tumor in a personalized fashion, without requiring a beam degradation process via artificial filters interposed between the beam and patient, which would produce the sort of contaminating and unnecessary neutrons that are common in other technologies.

These are the most advanced instruments currently available, which are far more energy-efficient than other alternatives, as they create much less unwanted radiation.

• A nozzle: Protons are extracted from hydrogen molecules and introduced into a linear accelerator that injects them at low speeds.
• An accelerator with four magnets, which keep the protons on circular paths. An electric field gradually increases their speed.
• A beamline. When a speed close to the speed of light has been reached, the protons leave the synchrotron and are guided towards the patient.
• A gantry, the area where patients are positioned, and where the protons are directed. The gantry rotates 360° so the most suitable treatment angle can be selected. It also has a 6D articulated robotic arm that operates on the table, facilitating optimal patient positioning during treatment. The gantry has a built-in cone-beam computed tomography to view the internal anatomy in real time prior to irradiation. This can be checked for each radiation session.

• It is the only facility in an inpatient cancer center, with all the patient-care, academic and research support this entails. The Navarre University Hospital makes available a reference center with 3,600 square meters dedicated to the Proton Therapy Unit that features advanced technology not previously available in Europe and the guarantees provided by a hospital environment. This facilitates access to any area of medical specialization in a single facility, key for patients with complex diseases, and offers comprehensive treatment.
• It is integrated as part of the Navarre University Cancer Center, an international reference in cancer diagnosis and treatment, as well as in the development of the most advanced, personalized precision cancer therapies, with interdisciplinary oncological areas, and access to clinical trials and international research projects.
• We have the leading technology on the market. The Hitachi synchrotron, found in international benchmark hospitals for cancer diagnosis and treatment in the United States and Japan, is an advanced particle accelerator that enables the release of a proton beam with the specific energy level for each patient’s tumor in a personalized fashion, without requiring a beam degradation process through artificial filters placed between the beam and the patient, which would result in the production of contaminating and unnecessary neutrons common to other technologies. These are the most advanced instruments currently available, with far greater energy efficiency, and much less unwanted radiation is created.
• Due to our professional experts: specialists who make up an international reference center in cancer treatment, with extensive training in proton therapy and boasting vast scientific output in clinical and translational radiotherapy innovation.