Different approaches to assessment of lymph nodes and surgical margin status in patients with ductal adenocarcinoma of the pancreas treated with pancreaticoduodenectomy

Aim: To develop a method of gross examination of pancreaticoduodenectomy specimens with pancreatic ductal adenocarcinoma, allowing adequate assessment of the entire pancreatic surface as a surgical margin, which would not affect the lymph node yield. Methods: We retrospectively compared the R1 rates (i.e., proportions of patients with microscopic residual tumour at surgical margins) and lymph node yield in a series of 67 consecutive cases of pT3 ductal adenocarcinomas diagnosed in pancreaticoduodenectomy specimens during three different periods of time and sampled using three different approaches: (1) period 2006-2007, when the pancreatic surface (except for the transection margin and superior mesenteric artery margin) was not examined; (2) period January-September 2008, when the posterior pancreatic surface (posterior circumferential radial margin) was examined using an improved method based on sampling of 2.0-2.5 mm thick consecutive slices perpendicular to the duodenal axis; and (3) period October 2008 - June 2009, when the whole surface of the pancreatic head was sampled using the approach mentioned above. Results: The R1 rates in three consecutive time periods were 23.5%, 40% and 53.8%, respectively. Median numbers of retrieved peripancreatic lymph nodes were 11.0, 12.0 and 14.0, respectively. Conclusions: The newly proposed approach allowed adequate assessment of the entire pancreatic head surface as a surgical margin and reduced the risk of under-detection of R1 status. Moreover, this approach did not affect the number of peripancreatic lymph nodes examined.