Body of the Pancreas - Structure, Function, Location

The body of the pancreas is the elongated, central portion of the gland situated between the neck and the tail. It forms the largest segment of the pancreas and lies transversely across the posterior abdominal wall. The body serves critical roles in both the exocrine and endocrine functions of the pancreas, containing a high concentration of acinar cells and endocrine islets. It is surrounded by vital vascular structures and is a key reference zone in both imaging and surgery.

Structure

The pancreatic body is prism-shaped in cross-section and lies retroperitoneally. It tapers gradually toward the tail and is traversed by the main pancreatic duct (duct of Wirsung), which collects secretions from surrounding acini and carries them toward the ampulla of Vater.

Histologically, the body contains:

Exocrine acinar cells: Clusters of cells producing digestive enzymes (amylase, lipase, proteases).
Islets of Langerhans: Endocrine cells scattered throughout the parenchyma, secreting insulin, glucagon, somatostatin, and pancreatic polypeptide.
Ductal system: Intercalated ducts join intralobular ducts that drain into the main pancreatic duct.

Location

The body of the pancreas lies horizontally in the upper abdomen, extending across the midline. It lies anterior to the abdominal aorta and L2 vertebral body and is located posterior to the stomach, separated by the lesser sac.

Structure	Relation to Pancreatic Body
Stomach	Anterior, separated by the lesser sac and peritoneum
Abdominal aorta	Posterior to the body
Splenic vein	Runs posteriorly along the superior border
Superior mesenteric artery	Courses inferior and posterior to the body
Left kidney and adrenal gland	Posterior and lateral to the left side of the body

Function

The body of the pancreas contributes significantly to the organ’s overall function:

Exocrine secretion: Acinar cells in the body produce and release digestive enzymes that help break down carbohydrates, fats, and proteins in the small intestine.
Endocrine regulation: The islets of Langerhans regulate glucose metabolism by secreting hormones like insulin (β-cells), glucagon (α-cells), somatostatin (δ-cells), and pancreatic polypeptide (PP cells).
Ductal transport: The main pancreatic duct collects secretions from this region and channels them to the duodenum via the ampulla of Vater.

Clinical Significance

The body of the pancreas is frequently involved in pathological and surgical conditions due to its central position and vascular proximity:

Chronic pancreatitis: Fibrosis and calcifications often localize in the body; can result in ductal strictures and exocrine insufficiency.
Pancreatic cancer: Tumors in the body often remain asymptomatic until advanced stages. They may invade nearby structures like the aorta, SMA, or splenic vessels.
Pseudocysts: Inflammation or trauma can lead to pancreatic fluid collections in the body, potentially compressing adjacent organs.
Distal pancreatectomy: The body and tail are commonly resected together in cases of benign tumors or low-grade malignancies.
Diabetes mellitus: Loss or dysfunction of β-cells in the body (and tail) can contribute to insulin deficiency.

The body of the pancreas is also a crucial structure in cross-sectional imaging (CT, MRI) for diagnosing retroperitoneal pathologies and in intraoperative navigation. Its deep, midline position makes it prone to delayed symptom onset in disease, necessitating a high index of suspicion during evaluation.