Prognostic importance of margin clearance in ampullary adenocarcinoma following pancreaticoduodenectomy in a Danish population-based nationwide study

Background: In this Danish nationwide population-based study, we evaluated the prognostically relevant minimum tumour-free margin width following pancreaticoduodenectomy (PD) for ampullary adenocarcinoma (AAC) and evaluated whether certain margins hold independent prognostic information. Methods: We included 128 patients who underwent PD for AAC from 2015 to 2019. Clinical and pathological data including well-known prognostic factors were retrieved from the Danish Pancreatic Cancer Database. Missing data were obtained by review of pathology reports and re-microscopy of resection specimens. All PD specimens were examined using a standardised pathological protocol including multicolour inking, axial slicing and exact reporting of margin widths. The cohort was dichotomised into involved and uninvolved groups, using different margin clearance definitions (0.5->= 3.0 mm). Results: Following PD for AAC, margin clearance of >= 1 mm was independently associated with improved chance of survival compared with <1 mm (HR: 0.30, 95 % CI: 0.14-0.64 (p = 0.002)). Posterior and anterior margin widths were narrower compared with superior mesenteric artery and vein margins. Posterior margin and anterior surface had isolated prognostic significance in multivariable analysis. Conclusion: Following PD for AAC, margin clearance of at least 1 mm is independently associated with improved survival. Our data further indicate that anterior surface and posterior margin hold particular prognostic value.