Feasibility of EUS-guided injection of irinotecan-loaded microspheres into the swine pancreas

BackgroundLC beads (Biocompatibles International plc) are designed for the time-released delivery of the chemotherapeutic agent irinotecan into focal, hypervascularized, hepatic tumors.ObjectiveTo determine the feasibility of EUS-guided injection of LC beads (with/without irinotecan) into the swine pancreas.DesignSurvival animal study.SettingAcademic center.SubjectsThis study involved 12 Yorkshire swine.InterventionLC beads without irinotecan and loaded with up to 300 mg of irinotecan were injected under EUS guidance with a 19-gauge needle into the tail of the pancreas. CT scanning and necropsy with histology were performed at day 7.Main Outcome MeasurementsFeasibility of the injections, gross and microscopic evidence of pancreatic inflammation, and clinical tolerance by the animals.ResultsAfter injection of LC beads with/without irinotecan, in 10 of 12 animals an intrapancreatic, hyperechoic focus with an average diameter of 2.2 cm was visible by EUS, and a hypodense area in the tail of the pancreas was visible by contrast CT. In 2 animals (1 with irinotecan and 1 without) no beads were seen on CT. In 10 of 12 animals, a depot of beads was located in the tail of the pancreas on gross inspection and histology. Drug depot with only localized pancreatic tissue reactions was seen on histopathologic review.LimitationsAnimal study.ConclusionThe EUS-guided injection of LC beads (with/without irinotecan) into the pancreas of the pig is feasible and safe. This technique is a potential minimally invasive local treatment option for locally advanced pancreatic cancer.