An audit of pathology lymph node dissection techniques in pylorus preserving Kausch-Whipple pancreatoduodenectomy specimens

Aims-To determine whether or not identifying recognised anatomical groupings of lymph nodes (LNs) improves LN yield in pancreatoduodenectomy resection specimens. Methods-All the pathology reports from pancreatoduodenectomy resection specimens between January 1997 and September 1999, for one specialist pathologist at the Royal Liverpool University Hospital, were examined retrospectively. The total number of LNs found in each specimen was determined and the method of identifying LNs established for each case. LNs were found using either (1) the UICC TNM anatomical groupings, termed grouped; (2) the Japanese Pancreatic Society classification, termed numbered; or (3) neither the grouped nor numbered classification, termed non-grouped. Results-A total of 50 reports (45 neoplastic, five chronic pancreatitis) were studied, 11 with non-grouped LNs, 14 with grouped LNs, and 25 with numbered LNs, including the five inflammatory cases. A median of 7.0 LNs was found in non-grouped cases, a significantly lower number than in the grouped cases (median, 12.0; Mann-Whitney U, p < 0.039) and numbered cases (median, 17.0; p < 0.0001). There was no significant difference in the LN yield between grouped and numbered cases (p = 0.1066). LNs were found most frequently in the inferior, posterior pancreaticoduodenal, and infrapyloric regions. Conclusions-A detailed knowledge of the anatomical distribution of LNs in pancreatoduodenectomy resection specimens significantly improves LN yield. It is suggested that illustrations of LN sites in resection specimens should be included in pathology guidelines/proformas to improve LN detection and, therefore, pathological prognostic data.