Dissecting the Pattern of Nodal Spread in Post-neoadjuvant Pancreatoduodenectomy

There has been long-standing debate about nodal dissection in pancreatoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC), with most studies examining the value of nodal yields, number of metastatic nodes and spatial location of metastases being conducted in the upfront surgery setting. With increasing use of a chemotherapy-first approach even in early stage PDAC, the validity of nodal parameters in post-treatment PD has been brought into question due to therapy-induced lymph node (LN) shrinkage. However, the available information is based on retrospective data or administrative registries, which only considered the number of examined and metastatic nodes, without detailed information regarding the dissection protocol and the influence of nodal metastases location. Back in 2013, corresponding to the standard lymphadenectomy definition release by the International Study Group of Pancreatic Surgery (ISGPS) and the diffusion of multi-agent chemotherapy regimens, an institutional, station-based nodal dissection protocol was established for post-neoadjuvant PD. The aim was to investigate whether the pattern of metastatic spread within the nodal basin is a superior quality metric for prognosis relative to the count-based classification system.