Pancreatoduodenectomy: Perspectives on a Standardized Grossing Protocol for the Practicing Pathologist

Abstract

The pancreatoduodenectomy or Whipple procedure is a complex oncologic surgical specimen with 2 dominant yet opposing standardized grossing protocols reported in the literature, the Leeds Pathology Protocol (LP) and the bivalving technique. The LP recommends the axial slicing of the pancreatic head perpendicular to the longitudinal axis of the duodenum, whereas the bivalving technique suggests sampling margins separately followed by bisecting the pancreas along the pancreatic and biliary ductal systems. An assessment can then be performed to determine which plane best serves to examine a particular tumor. This review provides a standardized grossing procedure in sufficient stepwise detail to be replicated by the practicing pathologist and is accompanied by an overview of the literature assessing strengths and limitations of both the LP and the bivalving technique. Factors that influence grossing method are discussed with diagnosis, stage, and margin status evaluated in additional detail, given their significant impact on treatment and prognosis. Consideration is given to adenocarcinoma diagnoses being dictated by the often difficult-to-determine tumor epicenter, the American Joint Commission on Cancer having recently changed their staging criteria in the eighth edition to be far more reliant on size and require enumerating lymph nodes, and the definition of a positive margin remaining controversial. An appreciation for the evidence or lack thereof allows an informed prosector to select a particular standardized method as determined by the unique characteristics of each individual tumor, which can best serve the clinician and patient.