Reassessment of the Necessity of the Proton Gantry: Analysis of Beam Orientations From 4332 Treatments at the Massachusetts General Hospital Proton Center Over the Past 10Â Years

The majority of practical beam approaches can be realized with gantry-less delivery, aided by limited beam bending and patient movements. Practical limitations of the MOVE geometry, and treatments requiring a combination of lying and sitting positions, may lower the percentage of head and neck patients who could be treated without a gantry. Further investigation into planning, immobilization, and imaging is needed to remove the practical limitations and to facilitate proton treatment without a gantry.