Evaluation of endoscopic-ultrasound-guided celiac ganglion irradiation with iodine-125 seeds: a pilot study in a porcine model

Background and study aims: Implantation of iodine-125 (I-125) seeds under the guidance of endoscopic ultrasonography (EUS) has been proved to be a safe alternative treatment option for advanced pancreatic cancer. The main purpose of this study was to evaluate the feasibility and safety of EUS-guided radiation of the celiac ganglia with I-125 seeds in a porcine model. Methods: Twelve domestic pigs were randomly divided into three groups. The pigs in group A had blank seeds implanted, and groups B and C had 0.4 mCi and 0.8 mCi I-125 seeds implanted, respectively. Enhanced CT scan and 3-D vascular remodeling were used to check the location of the seeds. All animals were killed and celiac ganglia were checked at 14 and at 60 days after procedure. Necrosis and apoptosis in celiac ganglia and adjacent vessels and organs were also observed. Results: EUS-guided implantations of I-125 seeds in celiac plexus were successful at first procedure in 10 animals. The remaining two animals were implanted successfully the next day. No severe complications occurred in any animal and no damage was found in the surrounding organs. At day 60 after operation, the apoptotic index in the ganglia was 0.53 in the 0.4 mCi group and 0.94 in the 0.8 mCi group. No apoptotic cells were found in the control group implanted with blank seeds. Damage to vessels and surrounding organs by radioactive seeds was observed in only one pig at each time point. Conclusion: EUS-guided implantation of I-125 seeds beside the celiac ganglia is a safe procedure and can induce apoptosis of local neurons. This new method may lead to an alternative treatment for pain accompanying pancreatic diseases in human.