Clinical decision during surgery for periampullary cancer should be made for the extent of resection, dissection plane, mode of reconstruction and etc. It should be based on the principle of oncologic surgery, evidence based surgery and sometimes theory and experience. Pancreatoduodenectomy (PD) can be customized according to host factors and tumor factors such as origin, location, nature and extent of tumor. Tumor spread pattern and site of recurrence are the important considering factors because they are different according to the tumor origin and location.
CBD cancer: Local spread patterns of CBD cancer include longitudinal invasion (both sides and each layer), transmural direct invasion (to pancreas, hepatoduodenal ligament including major vessels), lymphatic and peri-neural invasion, etc. Lymph node (LN) metastasis are frequently detected at station 12, 13, and 8. The most frequent patterns of loco-regional recurrence after PD for CBD cancer are around hepatoduodenal (HD) ligament including hepatico-jejunostomy site. So, PD for CBD cancer should include whole length of common duct and skeletonization of HD ligament vessels. Removal of nerve plexus of HD ligament and hepatic arteries is advised.
Ampulla of Vater (AoV) cancer: Loco-regional spread of AoV cancer include regional LN metastasis and direct invasion to duodenum and pancreatic head. It shows relatively high LN positivity even in T1 and mostly retro-pancreatic and peri-SMA nodes. Recurrence of advanced T stage AoV cancer is developed both systemic and regional area, whereas recurrence of T1, although it is not often, is mainly regional LNs, especially peri-SMA nodes. So, for more complete local control by surgery, peri-SMA node dissection is very important.
Pancreatic head cancer: Although standard PD and extended PD did not show any difference in recurrence pattern and survival outcome, PD for pancreatic head cancer can be tailored according to the tumor location. Pancreatic head cancer loco-regionally spreads along the lymphatic and nerve plexus that often end up with arterial invasion and directly invades portal vein/ superior mesenteric vein. Pancreatic cancer of superior anterior part of the pancreatic head can be closely located and easily invade to the duodenal bulb and common hepatic artery LN (#8) and hepatic artery nerve plexus. Uncinate process or ventral pancreas cancers are easily infiltrate to mesenteric vessels, peri-SMA nerve plexus and SMA LNs. Locoregional recurrence sites tend to be consistent with this spread pattern. So, while pylorus preserving PD (PPPD) is the procedure of choice for most CBD and AoV cancer, PD is indicated for the pancreatic head cancer located at the superior anterior (dorsal) part of the pancreatic head. Dissection of nerve plexus and LNs around hepatic artery may be beneficial for tumor located here. For ventral pancreas cancer, PPPD can be safely done and dissection of soft tissues around SMA including nerve plexus and LN is recommended. SMA approach such as mesenteric approach or mesopancreas excision is recommended for ventral pancreas cancer and cancer with suspicious mesenteric vessel invasion.