PRESTO: A Phase III Randomised Controlled Trial of Dose-escalated Proton Beam Therapy Versus Standard of Care Radiotherapy for Functioning Pituitary Tumours

The goal of this clinical trial is to evaluate whether a higher dose of radiotherapy can lead to better outcomes for participants with functioning pituitary tumours. The main question it aims to answer is whether a greater proportion of participants will achieve normal hormone levels with the higher dose of proton beam radiotherapy than with standard radiotherapy treatment doses. Following randomisation, participants will receive approximately 6 weeks of either standard dose radiotherapy (intensity-modulated radiation therapy or proton beam therapy, depending on age) OR escalated dose proton beam therapy. Following this, participants will be followed up for at least 2 years to monitor their condition. This includes pituitary, hormone level, tumour, neurocognitive, and ophthalmology assessments, as well as patient-reported quality of life outcomes and health economic measures.