Lymphadenectomy for Pancreatic Head Cancer: Standard or Extended?

Pancreaticoduodenectomy for Pancreatic ductal adenocarcinoma with standard or extended lymphadenectomy undergoing by the surgeons from Ruijin Hospital standard lymphadenectomy includes standard lymphadenectomy and No 5 6 8a 12b1 12b2 12c 13a 13b 14a 14b 17a 17b lymph nodes stations extended lymphadenectomy includes No8p 12a 12p 14c 14d 16 lymph nodes stations and those in standard lymphadenectomy( No 5 6 8a 12b1 12b2 12c 13a 13b 14a 14b 17a 17b) The details of all lymph nodes stations are described as below: No. 5, Suprapyloric lymph nodes; No. 6, infrapyloric lymph nodes; No. 8a, lymph nodes in the anterosuperior group along the common hepatic artery; No. 8p, lymph nodes in the posterior group along the common hepatic artery; No. 12a, lymph nodes along the hepatic artery; No. 12p, lymph nodes along the portal vein; No. 12b, lymph nodes along the bile duct; No. 12c (located next to 12b), lymph nodes around the cystic duct; No. 13a, lymph nodes on the posterior aspect of the superior portion of the head of the pancreas; No. 13b, lymph nodes on the posterior aspect of the inferior portion of the head of the pancreas; No. 14, lymph nodes along the superior mesenteric artery (a & b. right lateral side, c & d. left lateral side ); No. 16, lymph nodes around the abdominal aorta;.No. 17a, lymph nodes on the anterior surface of the superior portion of the head of the pancreas; No. 17b, lymph nodes on the anterior surface of the inferior portion of the head of the pancreas