Particle therapy is currently an effective tool in the fight against many cancers, and may have the potential to treat many more. The Cancer Particle Therapy Research Program seeks to improve and expand the treatment capabilities of particle therapy for cancer patients everywhere.

In pursuit of its goals, the program performs research into:

  • Refining existing treatment methods, like proton therapy
  • Developing new treatment methods, like heavy ion therapy and neutron capture therapy

Proton Therapy

Proton therapy is a modern and effective radiation treatment for cancer. As the first hospital-based proton treatment center in the world, we pioneered making this treatment widely available to cancer patients. The James M. Slater, MD Proton Treatment and Research Center has treated cancer and conducted research with protons for nearly 30 years. 

The Cancer Particle Therapy Research Program works to refine proton therapy. Our research, including a steady stream of clinical trials and data collection from patients treated with proton therapy, aims to continually improve proton therapy’s efficacy and precision. These improvements are particularly important to pediatric patients, as reducing radiation exposure can help avoid lifelong damage to developing bodies.

We believe there’s still much more this technology can offer and we intend to push past its current boundaries. With patient outcomes in mind, further research has the potential to both improve existing treatments and develop new treatment methods involving protons. Recently, clinical trials led to the use of proton therapy for early-stage breast cancer. Our program continuously designs and participates in clinical trials like this, targeting various cancers and other conditions.

Precision Proton Beam Targeting

Loma Linda University Cancer Center became home to a robotically controlled precision patient alignment system in 2010. This system is just one example of our staff pushing the limits in proton therapy. Robotic positioning of both the patient and the proton beam allows for precise targeting of tumors — down to a single millimeter. Because of the system’s efficacy and efficiency, proton therapy can be done with fewer treatments and has thus become available to more patients. 

The program aims to make proton therapy available to even more patients through the implementation of a scanning proton beam. This technology will allow for even more precision in proton beam placement. In turn, large and irregular-shaped tumors and tumors in sensitive areas will become much easier to treat in a shorter period of time.

Collaboration through Basic Science

Research investigators from many fields contribute to the advancement of proton therapy. Basic science informs a great deal of applied proton therapy and ultimately affects patient care. Some of the disciplines that shape proton therapy include:

  • Physics
  • Microbiology
  • Radiobiology
  • Genetics
  • Neurology
  • Chemistry

Basic science and physics / engineering research informs the application of proton therapy through several ongoing efforts. One of these is investigation into proton delivery optimization. For example, a team of physicists and engineers conducts research into modifying control systems and changing equipment configurations to improve precision and efficacy. 

Radiation Research Partnership with NASA

Another area of study focuses on the effects of proton beams, and specifically the effect radiation has on tissues, cells and cell components. Our research efforts even include partnering with NASA to study the effects of radiation exposure on astronauts. Experiments  from our researchers were included on five spaceflights and were able to better define risks associated with radiation. 

The research included studying the effects of spaceflight radiation exposure on cell cultures, animals and astronauts. Loma Linda University Cancer Center scientists used the findings in translational research, recommending adjustments to radiation dosing and refinements to proton therapy delivery. The end result was improved quality of care for our cancer patients.

Heavy Ion Therapy

Heavy ion therapy represents a potential leap forward in particle therapy for cancer. While heavy ion therapy delivers radiation treatment in much the same way as proton therapy, it’s both more precise and more effective. Treating tumors with carbon ions, for example, is two to three times more biologically effective than proton treatment. One immediate benefit is the ability to treat radioresistant tumors that proton or X-ray therapies cannot cure.

More basic and clinic research as well as technological innovation is required to fully understand and utilize the potential of heavy ion therapy. While about a dozen heavy ion treatment centers have been built around the world, none currently exist in the U.S. Further, most medical centers don’t have the research focus and science integration needed to secure crucial funding from the National Cancer Institute.

As an academic medical center, Loma Linda University Health is uniquely positioned to conduct heavy ion therapy research. In 1990, Dr. James M. Slater paved the way in particle therapy by opening the first hospital-based proton treatment center. Today, our researchers are currently investigating the feasibility of building a next-generation heavy ion treatment center in a hospital environment.

In 2015, Dr. Reinhard Schulte became a principal investigator on an NCI planning grant to reestablish ion therapy research in the U.S. Dr. Schulte worked alongside Dr. Slater and has more than 25 years of clinical and research experience in proton therapy. Dr. Schulte believes that Loma Linda University Health has the capability to continue its legacy of improving cancer patient outcomes through proton and heavy ion therapy.

“When we first started looking into heavy ion therapy, Dr. James M. Slater told me we should pursue it. He told me that we have been pioneers before — and that we can be pioneers again.”

Neutron Capture Therapy

Proton and heavy ion therapies can be extremely effective tools in treating visible tumors. However, they lack the ability to target isolated cancer cells that have spread to nearby tissues. Neutron capture therapy, while still under development, has shown the potential to precisely target and eliminate cancer cells that have infiltrated healthy tissues.

In neutron capture therapy, the patient is first injected with a drug designed to molecularly target specific cancer cells. This drug delivers, for example, harmless, non-radioactive boron-10 atoms to these cancer cells but not to normal cells. Next, the patient is exposed to an intense field of low-energy (slow) neutrons (known as epithermal neutrons). The neutrons set off a nuclear reaction in the boron atoms, emitting helium and lithium ions of a very limited range (less than a cell diameter). The ions kill cancer cells without damaging nearby normal cells.

Neutron capture therapy requires the use of both a specialized particle accelerator and molecularly targeted boron compounds. Because Loma Linda University Cancer Center has experience with both, we’re uniquely positioned to advance research into neutron capture therapy. Collaboration with our Molecular Imaging & Therapeutics Research Program (which is already equipped to support boron delivery drugs) would catalyze such research.

Program Members