Technical limitations of lymph node mapping in pancreatic cancer

Identification of the Lymphatic Drainage Pathways from the Pancreatic Head Guided by Indocyanine Green Fluorescence Imaging during Pancreaticoduodenectomy

“…Several studies have tried to identify the lymphatic pathways in pancreatic cancer patients to determine the optimal lymphadectomy procedure, however the pattern of lymphatic drainage and draining areas remained poorly defined [22,23,24,25,26,27,28,29,30,31,32,33,34,35]. Deki and Sato [22] reported the lymphatic pathways of the pancreas by dissecting the lymphatic vessels using a cadaver.…”

“…Although these studies did provide useful information, as they used only autopsy specimens, they could not identify the physiological lymphatic flow from the pancreas in a real-time fashion. In another study, sentinel lymph node mapping of pancreatic head cancer was studied by methylene blue dye injection, however the study failed and concluded that it was not possible to identify lymphatic drainage from the pancreatic head using their technology [34]. …”

The lymphatic system and pancreatic cancer

“…Today, a broad range of similar pancreatic resection procedures are in use in modern surgical practices around the world. Differences in primary tumor placement within the pancreas—head/neck vs. body/tail—and tumor invasion into surrounding tissues and organs often necessitate customization of resection [44–55] beyond the traditional PD to such procedures as distal pancreatectomy with or without splenectomy [41,56], pancreaticogastrostomy [35], pylorus-preserving PD [37,38,40], pylorus-resecting PD [40], subtotal stomach-preserving PD, pancreatojejunostomy, duodenum-preserving head resection, wedge resection of inferior vena cava, and total [39] or regional [57] pancreatectomy [58,59]. …”

“…Evidence suggests that metastasis to lymph nodes is an early event in pancreatic cancer progression, and presence of tumor cells in lymph nodes represents one of the most negative prognostic factors with respect to patient outcomes [8,27,29,37,60–63]. Conservative surgical views support the standard PD with loco-regional lymphadenectomy [27,31,34,36,38,42,56,59,64–74], while others, most notably numerous Japanese groups, advocate that a more radical PD with extensive removal of retroperitoneal soft tissue and extended lymphadenectomy [27,34,39,42,75–84] results in better patient outcomes. Collected studies in Table 1 [8,27,31,34,36,37,39,40,42,59,64–75,77–99] demonstrate the broad range of study designs and conclusions that have fueled this debate.…”

“…Conservative surgical views support the standard PD with loco-regional lymphadenectomy [27,31,34,36,38,42,56,59,64–74], while others, most notably numerous Japanese groups, advocate that a more radical PD with extensive removal of retroperitoneal soft tissue and extended lymphadenectomy [27,34,39,42,75–84] results in better patient outcomes. Collected studies in Table 1 [8,27,31,34,36,37,39,40,42,59,64–75,77–99] demonstrate the broad range of study designs and conclusions that have fueled this debate. A recent set of randomized, controlled clinical trials from several centers around the world and a mathematical model of outcomes prediction have concluded that extended lymphadenectomy does not improve survival over traditional, more conservative resection and that quality-of-life may be decreased with more radical surgery [67–70,72,74,81,83,87,88,95].…”