Mesopancreas: A boundless structure, namely R1 risk in pancreaticoduodenectomy for pancreatic head carcinoma.

BACKGROUND: The mesopancreatic resection margin after pancreaticoduodenectomy for carcinoma of the head of the pancreas is of great interest with respect to curative resection, since the neoplastic involvement of this margin was shown to be the primary site for R1 resection. In this review the current knowledges of the surgical anatomy of the so-called mesopancreas and the mesopancreas excision techniques are summarized.

METHODS: References were identified by searching Pubmed database using the search terms "mesopancreas" and "meso-pancreatoduodenum" until June 2013 and through searches of the authors' own files. Five studies were included in this review.

RESULTS: Original contributions with regard to the anatomy of the retropancreatic area and specific technical descriptions of so-called "total mesopancreas excision" provided by published studies are pointed out.

CONCLUSIONS: Because there is no "meso" of the pancreas, and due to the continuity of the mesopancreatic and para-aortic areas, surgical dissection should be extended to the left of the superior mesenteric artery and include the para-aortic area to achieve the most complete possible resection of the so-called mesopancreas and minimize the rate of R1 resections due to mesopancreatic margin involvement. This extended mesopancreatic resection cannot be accomplished en bloc even if the removal of the dissected mesopancreatic tissues is performed en bloc with the head, uncus, and neck of the pancreas, i.e., with the pancreaticoduodenectomy specimen.