Routes of lymphatic drainage from the pancreas: a suggested segmentation.

The peripancreatic lymphatics were dissected after intrapancreatic injections of different colorants by territory. The aim of this study was partly to determine the lymphatic drainage routes specific to each pancreatic segment, and partly to define the nodal relay stations for each territory. Whatever the site of injection in the segment of the body and tail, the dye followed the splenic and inferior pancreatic pathways before reaching a left intercelio-mesenteric node (ICMN) and then the supra- and infrarenal nodal groups. However, three distinct drainage routes emerged for the head of the pancreas. The lymphatics of the uncus (anterior and posterior aspects) follow the superior mesenteric route to reach a right ICMN and then the supra- and infrarenal relays bilaterally. Rarely, the lymphatics of the posterior uncus may pass directly to the supra- and infrarenal relays. The anterosuperior segment of the head drains by the gastroduodenal route. This route crosses the superior border of the pancreas and joins the right ICMN. There is an inferior route for this segment which turns back along the inferior border of the isthmus. After injection into the posterosuperior segment of the head, the dye frequently refluxes along the common bile duct and hepatic artery and stains the pericholedochal and hepatic pedicular nodes. When the dye is not entirely collected by these large nodal stations, it goes to join the right ICMN. The right ICMN is the principle relay station for the head of the pancreas. The dye flows only from the pericholedochal relays towards the right ICMN, never in the opposite direction (right ICMN to pericholedochal relays).(ABSTRACT TRUNCATED AT 250 WORDS)