Surgical excision of mesopancreas in pancreatic cancer – is it necessary

The presentation "Surgical Excision of the Mesopancreas in Pancreatic Cancer – Is It Necessary?" explores the oncological significance of mesopancreas excision in pancreatic head cancer. It reviews the anatomical definitions, surgical techniques, and histopathological considerations of the mesopancreas as a retroportal structure, emphasizing its impact on resection margin status (R0 vs. R1), local recurrence, and survival rates. The study highlights the importance of high-quality surgery with extended lymphadenectomy, vascular resection, and a "no-touch isolation" technique to optimize long-term oncological outcomes.

1. Surgical excision of mesopancreas in pancreatic cancer – is it necessary? Spitalul Clinic Județean de Urgență – Tg.Mureș -Clinica Chirurgie I Universitatea de Medicină, Stiințe si Tehnologie ,,George Emil Palade “ Targu Mures Dr.C osma Catalin-Dumitru (1,2) Dr.Co jocaru Iulia Ioana (1) Dr.Cosmin Nicolescu (1,2) Prof.Dr.Calin Molnar (1,2)

2. Pancreatic- Digestive Anastomosis: Achille’s heel

3. MESOPANCREAS - DEFINITION Göckel (in analogy with mesorectum) - ferm and well vascularised peripancreatic structure which contains fat tissue, nerve fibers, lymph nodes located behind the head of the pancreas between the uncinate process , SMA and SMV JPS (Japanese Pancreas Society) - PL ph I si PL ph II Kawabata - mesopancreasduodenum Bouassida - “ retroportal lamina” Muro - P-A ligament Xu - entitatea anatomical entity bounded on the left by the Celiac Trunk and SMA, on the right by DII, superior HA, inferior DIII and anterior by the pancreas Singhirunnusorn and Adham - a triangle bounded by the Celiac Trunk , SMA and HA - Although easy to identify in normal conditions , no surgeon is 100% sure of macroscopic R0 resection in pathological conditions

4. Topographic ratios of the pancreas Head PV and its origin Right Renal Vein, End part of Left Renal Vein The Right Diaphragmatic pillar Neck Superior- Common Hepatic Artery Inferior –origin of the Mesenteric Vessels Anterior -Pylorus Posterior PV consisting from SMV and the Splenomezaraic trunk Body Anterior- the posterior part of the stomach Inferior – the duodenum-jejunal flexure and the jejunum Posterior - Aorta, and the Celiac Artery ,the celiac plexus, the Left Diaphragmatic Pillar, inferior part of the left adrenal gland, anterior part of the left kidney , left renal vessels , lineal vessels , lymph nodes Tail The pancreaticolienal to lienalrenal ligament Inferior part of the spleen Anterior – lienal vessels

5. REDEFINING THE NEGATIVE RESECTION MARGIN Histopathological status of the resection margin -prognostic factor influencing local tumor recurrence and distance survival Objective of every surgeon: - negative resection margin R0 -“high quality surgery”- low rate of R1 Vascular resection/sutures/reimplantation have shown that don’t influence survival rate

6. Circumferential resection edge Circumferential resection edge Anterior edge = anatomical edge Posterior edge - retroportal lamina(R1)= risk of incomplete resection Inferior edge– uncinate proces (R1)= risk of incomplete resection

7. MESOPANCREAES (POSTERIOR EDGE OF RESECTION) (unclear) n eclara –EMBRIOLOGICAL (undefined) n edefinita -ANATOMICAL (unsure) n esigura - INTRAOPERATIVE (unfriendly) n eprietenoasa - ANATOMOPATHOLOGICAL (necessary) n ecesar - PROGNOSTIC 5N

8. POSTERIOR EDGE Unclear –EMBRIOLOGICAL The pancreas comes from the Endoderm Week.5 Fusion with the pancreas Week.6 After Week.6 contact with the Duodenum. Celiac Artery and Superior Mesenteric Artery are considered structures of the mesopancreas. Fusion with the peritoneum makes the pancreas an extraperitoneal organ

9. POSTERIOR EDGE Undefined -ANATOMICAL Lymphatic perineural layer localised posterior of the pancreas, which extends from the posterior part of the head of the pancreas to the posterior part of the mesenteric vesseles (SMA and SMV). Posterior surface of the SMV and PV; Anterior surface of the Aorta and the Celiac Trunk, origin of the SMA Lateral- the semicircles of the Celiac Trunk Kawabata, 2012 - Conjunctive tissue along the IPDA and the First jejunal artery, including the tissue surrounding the SMA

10. POSTERIOR EDGE Unsure- INTRAOPERATIVE macroscopic This technique highlights tumor invasion after transsection of the neck of the pancreas and the bile duct, and the tissue is taken from the SMA or from the resection edge of the uncinate process Frozen Section R0 = R1 > 50% Axial Slicing Surface of section <1 mm rule (R >1mm , R 0-1mm, R0 mm)

11. POSTERIOR EDGE Unfriendly- ANATOMOPATHOLOGICAL

12. POSTERIOR EDGE Necessary- PROGNOSTIC •R0 vs. R1: 26.5 – 37 months vs. 11 – 15.4 months R0 - edge: 2 years survival - 40% R1 - edge: 2 years survival - 20% Survival

13. POSTERIOR EDGE Necessary - PROGNOSTIC Type to enter a caption.

14. Resection edge - R0 (72,4%) - R1 - 27,6% Vascular resections/sutures/reimplantation - 8 ,06% Extensive lymphadenectomy ( between the Aorta and the ICV - 66 % ) R0 (72,4%) R1 (27,6%) 42,1% in 2014 2 ,46% in 202 3 R1 Surgery Clinic 1- Tg.Mures Emergency Clinical Hospital 68 cases

15. Surgical Approach Posterior approach Artery first Approach between the Gerota fascia and peritoneum (“hanging manoeuvre”) 4. Vascular intrathecal approach 5. “no touch isolation” technique TME - Concept

16. Conclusion The excision of the meso-pancreas in the oncological surgery of the pancreatic neoplasm represents a challenge for experienced surgical teams and a hope of life for patients.

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