What is Patient Positioning in Radiotherapy?

Radiotherapy is all about precision. It involves meticulously outlining the 3D shape of a tumor, accurately targeting it with radiation beams, and—especially with proton or particle therapy—calculating the exact "length" of those beams. The goal is simple: deliver a radiation dose powerful enough to destroy all tumor cells while minimizing damage to surrounding healthy tissue.

But achieving that balance is anything but simple.

Clinicians must avoid critical anatomy in the patient’s body, ensuring that healthy cells receive as little radiation as possible. To do this, treatment is spread across multiple sessions (fractions), requiring patients to be positioned in exactly the same way each time. Even the slightest variation could impact the effectiveness of the treatment or increase unintended radiation exposure.

This is where patient positioning devices play a crucial role. These medical devices help ensure patients remain in the correct position during treatment. But positioning a patient isn’t just a technical challenge—it’s also a human one. Imagine an elderly woman who has recently undergone neck surgery, is in the middle of her third cycle of chemotherapy, and now has to lie completely still for extended periods. For her, comfort and ease of setup are just as critical as precision.

Adding another layer of complexity, radiation can be blocked or distorted by dense materials. Ideally, nothing should be between the beam and the patient. Patient positioning devices must be structurally strong enough to accommodate patients of all sizes, including those with limited mobility or higher body weights, ensuring stability and precision without compromising comfort or accessibility—yet they cannot contain metals that would interfere with radiation beams or medical imaging. This means these devices must be:

• Low density

• Structurally strong

• Comfortable

• Adaptable to different body types and cancer locations

• Quick and easy to set up

This is why only a handful of manufacturers worldwide specialize in developing these devices. We've evolved significantly from the early days of literally bolting patients to the treatment table. Back then, crude and rigid restraints were used to keep patients still, often causing discomfort and stress. The introduction of thermoplastic masks was a major step forward, allowing for safer and more adaptable immobilization. However, despite nearly 40 years of advancements in radiotherapy, patient positioning devices like these have remained largely unchanged—raising the question of why innovation in this area has stalled.

This isn’t just an open question—it’s a real concern. While treatment technologies like IGRT, AI-driven planning, proton therapy, and robotic positioning continue to push boundaries, patient positioning remains the foundational element that all of these technologies depend on. Given how fundamental positioning is to every single radiotherapy treatment, shouldn’t innovation in this space keep pace?

This leads us to a bigger discussion:

Is Patient Positioning Falling Behind in Radiotherapy Innovation?

—Bas