The characteristics of lymph node metastasis in pancreatic head cancer

Objective:To explore the characteristic of lymph nodes metastasis in order to define the lymph node dissection in radical resection of pancreatic head carcinoma.Methods:Operative microscope method was applied in 46 specimens after radical resection of the pancreatic head cancer to search lymph nodes.The lymph nodes were grouped in detail and the metastatic frequency of each group was compared.Results:The mean number of harvested lymph nodes per patient was 41.8.There were 32 specimens with positive lymph nodes,the most common involved sites were No.13.14.12.8and 16 lymph nodes.Six pancreatic cancer derived from the uncinate process had superior mesenteric vessel lymph nodes metastasis without involvement of post-pancreatoduodenal lymph nodes.The involved lymph nodes in paraaortic region almost located in the triangular region surrounded by the abdominal aorta,inferior vena cava and left renal vein.Conclusion:In case of radical cancer resection,extensive lymph nodes dissection is necessary even though a small tumor mass localizes in the pancreas.More attention should be paid to the lymph nodes around the superior mesenteric vessel,especially when those tumors derived from the pancreatic uncinate process.It is important to clear the lymph nodes in the triangular region surrounded by the abdominal aorta,inferior vena cava and left renal vein.