> ## Content Index > Fetch the complete content index at: https://www.theamericanquorum.com/llms.txt > Use this file to discover other available public pages before exploring further. # Upright Proton Radiotherapy Enters Clinical Use - URL: https://www.theamericanquorum.com/upright-proton-radiotherapy-enters-clinical-use/ - Published: 2026-09-28T09:53:17.000Z - Updated: 2026-09-28T09:53:17.000Z - Description: An upright proton-radiotherapy system has entered clinical use after FDA clearance and technical commissioning, potentially reducing facility complexity while patient-outcome advantages remain unproven. - Author: Kenneth R. Deans Jr. - Tags: Healthcare An upright proton-radiotherapy system has moved from engineering validation into patient treatment, a milestone that could reduce the space and mechanical complexity required for some advanced cancer centers. The achievement is clinically meaningful, but it is not yet evidence that upright treatment improves survival or tumor control. ## First patients treated in an upright position Leo Cancer Care said Sunday that its Marie patient-positioning and imaging platform was used for a first clinical treatment in June and is now operating with a compact, fixed-beam proton accelerator. In the [company’s September 27 announcement](https://leocancercare.com/news-and-events/press-release/leo-cancer-care-brings-into-clinical-use-an-upright-radiotherapy-platform-cleared-for-use-with-any-radiation-beam/?ref=theamericanquorum.com), the manufacturer described a workflow in which the radiation beam stays fixed while the seated or standing patient is slowly rotated into planned beam angles. That reverses the usual geometry of proton therapy. Conventional systems commonly position a patient horizontally while a massive gantry rotates the beam around the treatment table. A fixed beam and rotating patient platform can shrink the installation’s footprint and avoid the engineering demands of a multi-story rotating structure. The potential gain is primarily operational: a smaller facility may cost less to build and may make proton therapy feasible for health systems that cannot accommodate a conventional gantry. The platform integrates an upright CT scanner, treatment planning, positioning and image guidance so clinicians can scan and treat a patient in the same posture. That consistency is important because organs can shift or change shape when a person moves from lying down to sitting or standing. ## Commissioning data cleared the technical threshold A 31-author engineering team reported the system’s clinical commissioning in a [preprint released September 21](https://arxiv.org/abs/2609.25141?ref=theamericanquorum.com). The researchers evaluated beam output, imaging, patient-positioning accuracy and treatment plans before clinical use. Their report describes the installation as the first ultra-compact, gantry-free upright proton system to complete comprehensive commissioning. Commissioning is the formal process through which medical physicists test whether a treatment machine performs within defined tolerances before it is used on patients. It does not establish comparative patient benefit. Instead, it demonstrates that dose delivery, imaging and mechanical positioning are sufficiently controlled for clinical operation. Earlier technical work on the vertical CT component found submillimeter spatial integrity and strong dose-calculation agreement for test plans. The [independent technical assessment](https://arxiv.org/abs/2510.21990?ref=theamericanquorum.com) reported 99.8% gamma agreement for photon plans and 90.6% for proton plans under a stringent 1%/1-millimeter test, with all plans exceeding 98% under the more typical 3%/2-millimeter criterion. The authors also identified weaker low-contrast performance and nonuniformity in larger test objects, showing that the new geometry carries tradeoffs as well as advantages. ## What the FDA clearance covers The Food and Drug Administration cleared the Marie system in July 2025\. The agency’s [510(k) summary](https://www.accessdata.fda.gov/cdrh%5Fdocs/pdf25/K250970.pdf?ref=theamericanquorum.com) says it is intended for health professionals to image and position patients upright rather than in the conventional supine position and to work with compatible fixed-beam radiation systems. A separate [FDA clearance for the Mevion S250-FIT accelerator](https://www.accessdata.fda.gov/cdrh%5Fdocs/pdf25/K253406.pdf?ref=theamericanquorum.com) describes integration with the Marie device for accurate patient positioning. A 510(k) clearance means the agency found the device substantially equivalent to a legally marketed predicate for its intended use. It is not a finding that upright proton therapy produces better cancer outcomes than conventional treatment. That distinction matters because the manufacturer’s announcement emphasizes comfort, access and infrastructure savings, while the supporting clinical literature is still developing. ## Possible benefits and unanswered questions Some patients may find an upright posture more tolerable than lying flat, particularly people with breathing limitations, pain, mobility problems or anxiety. Imaging and treatment in the same position may also reduce the risk that anatomy shifts between planning and delivery. For certain tumors, gravity and posture could change organ motion or separate healthy tissue from the treatment target in useful ways. Those possibilities need disease-specific trials. Researchers must determine whether patients can remain reproducibly positioned across many sessions, whether posture improves dose distribution for particular cancers and whether any gains translate into fewer side effects or better tumor control. Safety procedures also have to account for fainting, fatigue and involuntary movement in patients receiving difficult treatment. The economic case likewise requires independent measurement. Eliminating a rotating gantry may reduce construction and maintenance costs, but total cost depends on the accelerator, shielding, imaging, staffing, throughput and reimbursement. A smaller room does not by itself guarantee that treatment will become affordable or geographically accessible. ## A platform milestone, not a clinical verdict The move into clinical use is a genuine milestone because it places a novel geometry into a regulated, commissioned treatment workflow. It also gives researchers access to real-world operational and patient data that laboratory studies cannot provide. The evidence supports a restrained conclusion: upright proton therapy can now be delivered with a cleared system that has passed technical commissioning. Whether it is more comfortable, less expensive or clinically superior will depend on comparative studies across tumor sites and patient groups. The next phase is therefore less about proving that the machine works and more about establishing where its different geometry meaningfully improves care.