Although DP-CAR includes en bloc resection of the CA, CHA, and plexus of the SMA, reconstruction of the arterial system is not required because of early development of a collateral arterial circulation via the pancreatoduodenal arcades from the superior mesenteric artery. After division of the CA with the CHA and splenic artery (SA), the hepatic and gastric arterial flow depends on the flow from the gastroduodenal artery (GDA), which should, therefore, definitely be preserved with the pancreatic head during DP-CAR. The collateral pathways via the SMA, pancreatoduodenal arcades, and GDA maintain the arterial blood supply to the hepatobiliary system. Since the collateral pathways also ensure arterial flow to the right gastroepiploic artery, the entire stomach can be preserved (Fig. 13.2).

Preoperative coil embolization of the CHA is routinely used to enlarge the collateral arterial pathway in some institutes, so as to reduce ischemia-related complications such as ischemic gastropathy, liver abscess, and perforation of the biliary system [7].

Tumor progression is cautiously evaluated mainly with preoperative multi-detector row computed tomography (MD-CT), with supplemental use of magnetic resonance imaging (MRI) and endoscopic ultrasonography (EUS). The indication for DP-CAR is locally advanced ductal adenocarcinoma of the body of the pancreas, such as that involving or abutting the CHA, the root of the SA, and/or the CA, without involvement of the GDA, SMA, and inferior pancreatoduodenal artery. Patients with involvement of less than approximately half the circumference of the SMA plexus should be considered candidates for DP-CAR because complete dissection of the SMA plexus without exposing the cancer can be achieved by dividing the plexus on the side opposite to that of the tumor. For oncologically safe ligation and division of the root of the CA in front of the aorta, a 5–7 mm noncancerous length of the CA from the adventitia of the aorta is required (Fig. 13.3).

Even if the tumor of the pancreatic body invades other organs directly, DP-CAR could be completed with concomitant resection of the organs, including the alimentary tract, the left adrenal gland, and/or the left kidney. However, in the case that a tumor has invaded the stomach to a depth that necessitates full-thickness resection, total gastrectomy should be considered because healing of the anastomosis might be disturbed by an insufficient collateral arterial flow.

DP-CAR usually includes resection of the distal pancreas and the spleen, together with en bloc resection of the celiac, common hepatic and left gastric arteries, the celiac plexus and bilateral ganglions, and the circumferential nerve plexus around the SMA. Left perirenal fat tissue, the left adrenal gland, the entire retroperitoneal fat tissue containing lymph nodes cranial to the left renal vein, and the inferior mesenteric vein are also resected. The entire alimentary tract should be preserved; however, cholecystectomy is performed for preventing postoperative ischemic rupture of the gall bladder (Fig. 13.4).

To achieve pathological margin-free (R0) resection, a systematic procedure, which consisted of right and left dorsal approaches to provide sufficient cancer-free margin from the tumor is rather important. In the right dorsal approach, the lower parts of the SMA are exposed following Kocher’s maneuver, with complete eradication of the right celiac ganglion and the right para-aortic nodes by exposing the right crus of the diaphragm. The plexus of the SMA is first divided at the dorsal end (opposite to the side of the tumor), and the excision is extended by 4–5 cm in the longitudinal direction. The median arcuate ligament has to be divided to expose just the root of the CA where it should be divided (Fig. 13.5). In the left dorsal approach, en bloc resection of the retroperitoneal fat, together with the upper part of the perirenal fat, including the left adrenal gland cranial to the left renal vessels are performed in exposing the left crus. The left adrenal artery and vein were divided during the procedure. In this approach, the left para-aortic nodes and ganglions are completely dissected. The partial mesocolon covering the tumor was cautiously dissected with the pancreatic parenchyma (Fig. 13.6).