The Pancreas: Anatomy, Dual Functions, Major Diseases, and Cutting-Edge Therapies

The pancreas is a retroperitoneal gland (~6–10 inches) with both exocrine (digestive) and endocrine (hormonal) roles—making it unique and clinically complex.

Anatomy & Physiology

• Exocrine (95%): Acinar cells secrete lipase, amylase, proteases into ducts → duodenum for fat, carb, protein digestion.
• Endocrine (1–2%): Islets of Langerhans: β-cells (insulin ↓glucose), α-cells (glucagon ↑glucose), δ-cells (somatostatin), PP cells (pancreatic polypeptide).

Major Diseases

• Acute Pancreatitis: Gallstones (40%), alcohol (30%), hypertriglyceridemia, ERCP, medications. Ranson/APACHE scores predict severity.
• Chronic Pancreatitis: Recurrent inflammation → fibrosis, calcification, exocrine/endocrine insufficiency. Alcohol leading cause.
• Diabetes Mellitus: Type 1: autoimmune β-cell destruction. Type 2: insulin resistance + relative deficiency.
• Pancreatic Cancer (PDAC): 90% ductal adenocarcinoma. Risk: smoking, obesity, diabetes, chronic pancreatitis, genetics (BRCA, Lynch, PALB2). 5-year OS ~12%.
• Pancreatic Exocrine Insufficiency (PEI): Inadequate enzymes → malabsorption. Treated with PERT (pancreatic enzyme replacement therapy).

Surgical & Emerging Therapies

• Pancreatectomy (Whipple, distal, total) → lifelong PERT + insulin
• Islet autotransplantation (post-total pancreatectomy for chronic pancreatitis)
• Islet allotransplantation (type 1 diabetes; Edmonton protocol)
• Stem cell-derived β-cells (Vertex VX-880 in trials)
• Genetic screening, liquid biopsy, AI-enhanced imaging for early PDAC detection