A systematic review of the role of periadventitial dissection of the superior mesenteric artery in affecting margin status after pancreatoduodenectomy for pancreatic adenocarcinoma

Background: Resectable pancreatic ductal adenocarcinoma continues to carry a poor prognosis. Of the controllable clinical variables known to affect outcome, margin status is paramount. Though the importance of a R0 resection is generally accepted, not all margins are easily managed. The superior mesenteric artery [SMA] in particular is the most challenging to clear. The aim of this study was to systematically review the literature with specific focus on the role of a SMA periadventitial dissection during PD and it's effect on margin status in pancreatic adenocarcinoma. Study design: The MEDLINE, EMBASE and Cochrane databases were searched for abstracts that addressed the effect of margin status on survival and recurrence following pancreaticoduodenectomy [PD]. Quantitative analysis was performed. Results: The overall incidence of a R1 resection ranged from 16% to 79%. The margin that was most often positive following PD was the SMA margin, which was positive in 15-45% of resected specimens. Most studies suggested that a positive margin was associated with decreased survival. No consistent definition of R0 resection was observed. Conclusions: Margin positivity in resectable pancreatic adenocarcinoma is associated with poor survival. Inability to clear the SMA margin is the most common cause of incomplete resection. More complete and consistently reported data are needed to evaluate the potential effect of periadventitial SMA dissection on margin status, local recurrence, or survival.