Canine Exocrine Pancreatic Tumor Study Guide

Overview and Clinical Importance

Exocrine pancreatic tumors represent a rare but highly aggressive group of neoplasms arising from the exocrine (acinar or ductal) cells of the pancreas. Unlike the more commonly discussed insulinomas, which originate from the endocrine pancreas, exocrine pancreatic adenocarcinomas account for the majority of malignant exocrine pancreatic neoplasms in dogs. These tumors are characterized by their late clinical presentation, high metastatic rate (approximately 78% at diagnosis), and grave prognosis. Understanding the pathophysiology, diagnosis, and limited treatment options is essential for NAVLE success and clinical practice.

The canine pancreas is a V-shaped gland located in the cranial abdomen with both exocrine and endocrine functions. The exocrine portion comprises approximately 95% of the pancreatic parenchyma and is responsible for producing digestive enzymes, while the endocrine portion (Islets of Langerhans) produces insulin and glucagon. Exocrine pancreatic tumors arise from either the acinar cells (which produce digestive enzymes) or the ductal epithelium.

Anatomy and Pathophysiology

Normal Pancreatic Anatomy

The canine pancreas is a compound tubuloalveolar gland consisting of a right lobe (following the descending duodenum), left lobe (embedded in the deep leaf of the greater omentum near the stomach), and a body that connects the two lobes near the pylorus. The right lobe is larger and extends from the ninth intercostal space to approximately the fourth lumbar vertebra.