Proton therapy is undergoing a transformative shift with the introduction of upright patient positioning—an innovation that promises improved precision, enhanced patient comfort, and broader accessibility in cancer treatment.
Proton therapy has long been recognized for its ability to deliver highly targeted radiation while sparing healthy tissue. Historically, treatment has been performed with patients lying horizontally in the supine position, necessitating the use of large, expensive rotating gantries to direct the beam.
The move toward upright proton therapy represents a major advancement in cancer care. By positioning patients in a seated or perched posture, this approach simplifies treatment delivery and allows for more compact system configurations, addressing long-standing limitations in cost and footprint.
Upright positioning offers clinical advantages that extend beyond patient comfort. Research indicates that when patients are upright, their internal organs are more naturally aligned, which can reduce organ motion and improve targeting accuracy for proton beams.
For instance, Yang et al. demonstrated that upright positioning increases lung inflation and promotes more stable breathing patterns—particularly beneficial for thoracic and abdominal tumors, where motion management is critical [1].
Leo Cancer Care and Mevion are leading the charge in bringing upright proton therapy to the forefront.
Leo Cancer Care has introduced a patient-centric system featuring upright positioning and a diagnostic-quality CT scanner, compatible with fixed-beam systems. This allows imaging and treatment in the same orientation, enhancing planning accuracy.
Mevion is integrating Leo Cancer Care’s upright technology with its MEVION S250-FIT* Proton Therapy System. By placing the world’s smallest proton accelerator in a fixed position on the floor, Mevion eliminates the need for a gantry, enabling a more compact and efficient design. This configuration also facilitates future integration of advanced imaging modalities, such as MRI, into the treatment workflow.
Fixed-beam proton therapy has a long history, dating back over 30 years to pioneering work at Massachusetts General Hospital. Early applications were limited by insufficient positioning accuracy. However, today’s robotic positioning systems, such as those developed by Leo Cancer Care, offer millimeter-level precision, meeting the rigorous standards required for proton therapy.
Research by Susu Yan, Ph. D and Thomas Bortfeld Ph. D at Massachusetts General Hospital showed that over 80% of proton treatments do not require gantry angles beyond ±10°—a finding that reinforces the clinical viability of fixed-beam systems [2]. When combined with modern GPU-powered treatment planning and imaging, these systems can now match or even exceed the quality of gantry-based plans.
These innovations unlock new possibilities for expanding proton therapy access. By removing the need for large rotating gantries and integrating compact, upright solutions, hospitals and cancer centers can now consider installing systems within existing infrastructure.
What was once a niche, high-cost treatment modality is now becoming scalable and economically viable for a wider range of healthcare providers.
Beyond clinical and economic advantages, upright positioning enhances the treatment experience. Patients often report greater comfort and reduced anxiety in the seated posture. Being able to maintain eye contact with clinicians fosters a more collaborative treatment environment, helping patients feel more in control of their care.
A study from Centre Léon Bérard in France evaluated the Leo Cancer Care upright system and found that pelvic treatment reproducibility in upright positioning matched that of supine setups. Additionally, patient-reported comfort levels were significantly higher in the upright posture [3].
As research and clinical evidence continue to accumulate, upright proton therapy is poised to become a mainstream option. With companies like Leo Cancer Care and Mevion driving innovation, the future of proton therapy is more accessible, efficient, and patient-friendly than ever before.
REFERENCES
*The MEVION S250-FIT Proton Therapy System is not yet available for clinical use.