Duodenal enteroglucagonoma revealed by differential comparison of serum and tissue glucagon reactivity with Siemens' Double Glucagon Antibody and DakoCytomation's Polyclonal Rabbit Anti-Human Glucagon: a case report

INTRODUCTION: This case report demonstrates that the differential immunohistochemical reactivities of Siemens' Double Antibody Glucagon compared to DakoCytomation's Polyclonal Rabbit Anti-Human Glucagon allow for pathologic distinction of enteral versus pancreatic glucagonoma. CASE PRESENTATION: A 64-year-old Caucasian man was diagnosed with a duodenal enteroglucagonoma following presentation with obstructive jaundice. He had a low serum glucagon level using Siemens' Double Antibody Glucagon, a clinical syndrome consistent with glucagon hypersecretion. A periampullary mass biopsy proved to be a neuroendocrine tumor, with positive immunohistochemical reactivity to DakoCytomation's Polyclonal Rabbit Anti-Human Glucagon. CONCLUSIONS: Differential comparison of the immunohistochemical reactivities of Siemens' Double Antibody Glucagon and DakoCytomation's Polyclonal Rabbit Anti-Human Glucagon discerns enteroglucagon from pancreatic glucagon.