Precision Radiotherapy Using MR-linac for Pancreatic Neuroendocrine Tumours in MEN1 Patients

This trial is testing whether precision radiation therapy using an MR-linac machine — which combines MRI imaging with radiation delivery — can safely treat small tumors in the pancreas caused by a hereditary condition called MEN1 (Multiple Endocrine Neoplasia type 1), potentially avoiding the need for surgery. **You may be eligible if...** - You have MEN1 and have a pancreatic neuroendocrine tumor (pNET) between 1 cm and 3 cm - Your tumor is growing (1–4 mm/year) or was left behind after prior surgery - Your tumor board has determined surgery is an option for you but you choose to explore alternatives **You may NOT be eligible if...** - Your tumor is larger than 3 cm or is growing rapidly (more than 4 mm/year) - Your tumor is causing hormone-related symptoms (except for gastrinomas in the small intestine) - You are currently on somatostatin analog or chemotherapy - You have received radiation in the upper abdomen before - You have MRI contraindications (claustrophobia, metal implants) - You are pregnant or have other sites of cancer spread - You have very poor health status (WHO performance score 3–4) Talk to your doctor to see if this trial is right for you.