Stereotactic-body-radiation-therapy as a radical treatment for pancreatic-neuroendocrine-tumors. A preliminary experience

Introduction: Surgery is standard treatment for pancreatic-neuroendocrine-tumors (TNP) although it occasionally associated with high-rates of morbid-mortality. Radiotherapy can be an effective alternative in selected patients. Our objective to evaluate the efficacy SBRT (Stereotactic-body-radiation-therapy) as a radical TNP. Materials and methods: Between December 2017 November 2020, we prospectively analyzed 13 patients pathological diagnosis TNP <2cm treated part IRB-approved study. The endpoints study are local-control, tolerance, progression-free-survival overall-survival. Patients’ characteristics: 6 female (46%) 7 males (54%) mean age 55.6 years-old. Tumor location: head 3p (23%), neck body 6p tail pancreas 1p (8%). Octreoscan prior radiotherapy was positive 8p (61.5%). FDG-PET negative all but one patient (SUV <4). Before SBRT, two internal fiducial markers were placed into tumor by endoscopic ultrasound puncture simulation-CT obtained. Clinical-target-volume (CTV) included pancreatic tumor. Planning-target-volume (PTV) CTV 5mm expansion. Patients received 40Gy 5 fractions on every other day. IMRT IGRT intrafraction control motion Gating performed. Results: With median follow-up 13.6 months (range 1.8- 34.4), without evidence relapse. Acute tolerance excellent. Only (23%) showed asthenia. One p developed peptic ulcer follow-up. Conclusions: feasible well tolerated could diagnoses TNP, further studies necessary.