Pancreaticoduodenectomy is the only potentially curative intervention for malignant tumors of the pancreas. Other indications for pancreaticoduodenectomy include chronic pancreatitis, benign tumors of the pancreas, cancer metastatic to the pancreas, multiple endocrine neoplasia type 1 and gastrointestinal stromal tumors. The shared blood supply of the pancreas, duodenum and common bile duct, necessitates en bloc resection of these multiple structures. Pancreaticoduodenectomy is most often performed as curative treatment for periampullary cancer, which include cancer of the bile duct, duodenum, ampulla or head of the pancreas. In this setting vascular surgeons resect the involved portion of the vessel, and the vessel is repaired either via end-to-end anastomosis, repair of the side wall of the vein, or a vein graft. Occasionally a portion of the superior mesenteric vein or portal vein is attached or inseparable from the tumor. If the tumor encases (wraps around 50% or more of the vessel) the celiac artery, superior mesenteric artery, or inferior vena cava it is considered unresectable due to the lack of patient benefit from the operation while having very high risk. These structures are important to consider in this operation especially if done for resection of a tumor located in the head of the pancreas. Relevant nearby anatomy not removed during the procedure include the major vascular structures in the area: the portal vein, the superior mesenteric vein, and the superior mesenteric artery, the inferior vena cava. This portion is not done en bloc, as the gallbladder is removed separately. During the surgery a cholecystectomy is performed to remove the gallbladder. The surgeon will make a new attachment between the pancreatic duct and the jejunum or stomach. This means that while the liver remains with a good blood supply the surgeon must make a new connection to drain bile produced in the liver. While blood supply to the liver is left intact, the common bile duct is removed. If only the head of the pancreas were removed it would compromise blood flow to the duodenum, resulting in tissue necrosis. These arteries run through the head of the pancreas, so that both organs must be removed if the single blood supply is severed. The reason for the removal of the duodenum along with the head of the pancreas is that they share the same arterial blood supply (the superior pancreaticoduodenal artery and inferior pancreaticoduodenal artery). There are additional smaller branches given off by the right gastric artery which is also derived from the celiac artery. The vascular supply of the pancreas is from the celiac artery via the superior pancreaticoduodenal artery and the superior mesenteric artery from the inferior pancreaticoduodenal artery. This is an important first step as the presence of active metastatic disease is a contraindication to performing the operation.
Īt the very beginning of the procedure, after the surgeons have gained access to the abdomen, the surfaces of the peritoneum and the liver are inspected for disease that has metastasized. However, not all lymph nodes are removed in the most common type of pancreaticoduodenectomy because studies showed that patients did not benefit from the more extensive surgery.
Lymph nodes in the area are often removed during the operation as well (lymphadenectomy). The most common technique of a pancreaticoduodenectomy consists of the en bloc removal of the distal segment (antrum) of the stomach, the first and second portions of the duodenum, the head of the pancreas, the common bile duct, and the gallbladder.
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