Embolization of the Pancreas Using Microspheres: A Proof-of-Safety Study in a Porcine Model

Abstract

Particle embolization of the pancreas with the intent of producing tissue ischemia has not been evaluated, but could have valuable application in the oncologic realm. A pig model was used to evaluate safety and impact on pancreatic function. Embolization of the dorsal pancreatic artery using 100-300-micron particles was performed on fourteen Yorkshire pigs. Baseline and post-embolization glucose tolerance testing and serum amylase/lipase levels were obtained. Pigs were observed for two weeks to assess for behavioral signs of pain/distress, bowel changes, and changes to intake/output. After two weeks, euthanasia and necropsy with gross and histopathologic assessment of the pancreas was performed. Embolization was technically successful in all pigs. All animals survived the two-week follow up without evidence of pain/distress. There were significant increases in amylase and lipase at 24- and 48-hours (p < 0.001), which normalized by two weeks. There clinically significant change in glucose tolerance testing at 2 weeks. Bowel habits were unchanged without diarrhea. At necropsy, all examined pancreases had fibrosis in the distal body and tail, without gross evidence of ongoing inflammation. On histopathologic evaluation, all pancreases demonstrated fibrosis in the embolized portions without evidence of active inflammation in treated or adjacent pancreatic tissue. Particle embolization of the pancreas was feasible and tolerated by all tested pigs with transient amylasemia, lipasemia, and mildly impaired glucose tolerance, but without clinical or histopathologic evidence of acute pancreatitis and no evident impact on pancreatic endocrine or exocrine function.