Improved lymph node retrieval in Whipple specimens as a result of implementation of a new uncinate margin protocol

Abstract

Background. Lymph node status is an important prognostic factor in pancreatic and peri-ampullary adenocarcinoma. We recently changed our protocol for assessment of the uncinate margin of Whipple specimens and noted that lymph nodes were often present in uncinate margin sections. Materials and methods. Whipple specimens from 2004 to 2006 were divided into two groups, those that were handled according to the en face protocol, and those handled according to the radial protocol. The numbers of lymph nodes found in uncinate margin sections were assessed, as well as the total number of nodes found in the specimen. Results. Sixteen cases were handled according to the en face protocol, and 20 according to the radial protocol. In the en face group, 2 benign nodes were found in the uncinate margin (0.1 nodes per case), while in the radial group, 36 nodes (1.8 nodes per case) were identified (p=0.0005). Eight cases in the latter group had positive nodes in the uncinate margin sections. In two of these cases the positive lymph node was the only lymph node with metastasis, and in an additional case the involved node was one of two positive lymph nodes. Total lymph node retrieval was 15.5 lymph nodes per case in the en face group, and 20 nodes per case in the radial group (p=0.02). Discussion. The improved lymph node retrieval may be due to additional nodes found in radial sections of the uncinate margin, or alternatively, due to increased vigilance in specimen handling. In 3 of 20 cases, nodes found in the radial sections influenced staging.