Comparison of Standard Distal Pancreatectomy and Splenectomy with Radical Antegrade Modular Pancreatosplenectomy

For over 100 years distal pancreatectomy has been the standard procedure for tumors in the body of the pancreas. The two goals of pancreatic resection include complete tumor resection with a margin of normal tissue and removal of regional lymph nodes. Tumors of the pancreatic head have been the focus of much innovation in achieving these two goals. Much effort has gone into developing surgical techniques that help eliminate positive margins at the uncinate or posterior border in pancreatic head resections. Extensive lymph node mapping has afforded surgeons more opportunity to resect regional nodes as well. Pancreatic body and tail tumors are reported to be just as aggressive invading locally and metastasizing through lymph nodes, but very little had been done to address improving these two markers of operative success.1 Radical antegrade modular pancreatosplenectomy (RAMPS) addresses the apparent disparity between pancreaticoduodenectomy and standard distal pancreatectomy. Strasberg et al.1 describes an operative technique that allows for a more complete dissection posteriorly and incorporates lymph node mapping for resection of all regional nodes. RAMPS differs from a standard approach in that the initial dissection begins medially and the neck of the pancreas is transected early as well as the splenic vessels. The dissection continues posteriorly to the aorta at the celiac and superior mesenteric trunks. If the tumor does not break the posterior plane of the pancreatic body, the left adrenal gland is retained and the posterior plane of dissection continues left from medial exposing the left renal vein and clearing Gerota’s fascia off the left kidney. When the tumor breaks the posterior plane of the pancreas, the left adrenal is resected en bloc and the dissection continues posteriorly to the diaphragm using the retroperitoneal muscles as the posterior border, diaphragm as the superior border, and renal vein as the inferior border of the dissection plane. The rationale for this approach is to ensure a negative deep margin with complete regional lymph node dissection. Using lymphatic mapping by O’Morchoe,2 it is shown that there are two primary groups of nodes that should be considered N1 or regional (Fig. 1). The first is a ring of lymphatics fed directly by lymphatic drainage from the body and tail of the pancreas. The ring is comprised of gastrosplenic nodes incorporated in the gastrosplenic omentum, splenic nodes in the hilum of the spleen, infrapancreatic nodes deep to the pancreatic body, and gastroduodenal nodes. The second primary group lies along the aorta, in relation to the celiac and superior mesenteric arteries, and may receive direct lymph drainage from the pancreas and thus must be considered N1. Therefore, to achieve full resection of all potentially N1 nodes, a complete resection should include all the nodes of the ring described as well as the celiac lymph nodes and those anterior to and to the left of the superior mesenteric artery. Given the early ligation of the splenic vessels in the medial approach and necessity of removing the nodes in the splenic hilum, all patients undergoing RAMPS also undergo splenectomy. Fig. 1 Lymph node mapping of the pancreas. In summation, RAMPS offers improved visualization of the posterior dissection plane, offers early control of the major blood vessels encountered, early division of the neck of the pancreas, better control of the splenic vessels,3 and the lymph retrieval allows for a more complete regional nodal dissection. Using this technique, improved margin resection and lymph node retrieval for tumors of the body and tail of the pancreas have been reported compared with standard resection. We examined our experience with RAMPS compared with standard resection to determine differences in clinicopathologic outcomes.