**6. Venous resections**

The tumor invasion in the porto‐mesenteric system depends on the tumor localization and has no relation to the long‐term survival and recurrence. This is not a prognostic factor, but it is an indicator of the biological aggressiveness of the tumor [9]. Invasion of the tumor pro‐ cess in the mesenteric portal blood vessels was considered as a contraindication for radi‐ cal surgery until recently. Nowadays, this opinion has changed and vascular resections are considered justified if achievement of clear resection margins is possible. Radical resection may be performed in approximately 25—30% of the patients with preoperative diagnostic imaging data for invasion in the porto‐mesenteric system [1]. Superior mesenteric/portal vein resections are quite well studied in clinical trials and large series demonstrate equivalence in short‐term outcome and long‐term survival of the pancreatoduodenectomies combined with venous resections.

Absence of dissemination of the process toward superior mesenteric artery and celiac trunk, which is the prerequisite for achieving of clear resection lines, is the main principle in resec‐ tions of portal vein in the course of one duodenopancreatic resection [21]. The Japanese, as well as European and American experience, clearly demonstrate that positive resection lines are a prerequisite for recurrent lesions, as well as for lower survival. The level of infiltration of the tumor toward the porto‐mesenteric vein is finally determined along the course of surgical operation by mobilization of the specimen from the surrounding tissues and its left reposi‐ tioning to hang only from the growth. Resection of the vein and recovery of its integrity is the next step. It could be partial or segmental (**Figure 5**). Vein integrity is recovered by one of the following four methods:

**Figure 5.** Partial tangential resection of the portal vein sutured longitudinally.

because the proximal hepatic duct receives almost all of its arterial blood flow from the right hepatic artery after interruption of the blood flow from the right gastric artery. The aber‐ rant right hepatic artery may be infiltrated by the tumor, when the latter reaches the celiac trunk (upon early bifurcation and low position of the left hepatic artery) or when the artery branches from the superior mesenteric artery. Replaced right hepatic artery, branching from the superior mesenteric artery, in contrast to the accessory hepatic arteries, represents the only direct arterial branch toward the right lobe of the liver. When the right hepatic artery, branching from the superior mesenteric artery is infiltrated along the postero‐lateral bor‐ der of the head of pancreas, the pancreatoduodenal resection does not frequently require removal of these blood vessels, because the larger part of these tumors are localized more in front of the head of pancreas and uncinate process of pancreas. The whole common hepatic artery may rarely branch from the superior mesenteric artery (type IX), no identification of that anatomical variant and inattentive ligation of the hepatic artery requires performing of

A high rate of complete resection and favorable prognosis (estimated overall 5‐year survival rate of 42%) could be observed in selected patients with distal pancreatectomy with en bloc

The tumor invasion in the porto‐mesenteric system depends on the tumor localization and has no relation to the long‐term survival and recurrence. This is not a prognostic factor, but it is an indicator of the biological aggressiveness of the tumor [9]. Invasion of the tumor pro‐ cess in the mesenteric portal blood vessels was considered as a contraindication for radi‐ cal surgery until recently. Nowadays, this opinion has changed and vascular resections are considered justified if achievement of clear resection margins is possible. Radical resection may be performed in approximately 25—30% of the patients with preoperative diagnostic imaging data for invasion in the porto‐mesenteric system [1]. Superior mesenteric/portal vein resections are quite well studied in clinical trials and large series demonstrate equivalence in short‐term outcome and long‐term survival of the pancreatoduodenectomies combined with

Absence of dissemination of the process toward superior mesenteric artery and celiac trunk, which is the prerequisite for achieving of clear resection lines, is the main principle in resec‐ tions of portal vein in the course of one duodenopancreatic resection [21]. The Japanese, as well as European and American experience, clearly demonstrate that positive resection lines are a prerequisite for recurrent lesions, as well as for lower survival. The level of infiltration of the tumor toward the porto‐mesenteric vein is finally determined along the course of surgical operation by mobilization of the specimen from the surrounding tissues and its left reposi‐ tioning to hang only from the growth. Resection of the vein and recovery of its integrity is the next step. It could be partial or segmental (**Figure 5**). Vein integrity is recovered by one of the

coeliac axis resection for locally advanced pancreatic body cancer (**Figure 4**) [27, 28].

reconstruction.

202 Challenges in Pancreatic Pathology

**6. Venous resections**

venous resections.

following four methods:


The ISGPS proposes a classification of porto‐mesenteric resections according to the type of venous reconstruction [21]:

Type 1: Partial excision of venous wall with a suture closure.

Type 2: Partial excision of venous wall with a patch closure.

Type 3: Segmental venous resection with termino‐terminal anastomosis.

Type 4: Segmental venous resection with a conduit and at least two anastomoses.

More recent classification by Tseng et al. takes in general consideration the management of splenic vein along with the type of reconstruction [29]:

V1—Tangential resection with saphenous vein patch.


Shibata et al. divided SMV/PV resections into another four types being guided mainly from the localization of the resection line [30]:


It seems that the management of the splenic vein plays a crucial role during the reconstruc‐ tion of the SMV/PV confluence [31]. The classical technique of segmental venous resection includes transsection and ligation of the splenic vein. In technical aspect, this maneuver allows complete presentation of the superior mesenteric artery medially to the superior mes‐ enteric vein, and elongation of the superior mesenteric vein and portal vein (because the latter blood vessels are not adducted by the splenic vein) for performing of primary venous anasto‐ mosis after segmental venous resection. The retroperitoneal dissection ends with cutting by sharp manner of soft tissues anteriorly to the aorta and on the right side of the so presented superior mesenteric artery. As a result of that the specimen remains fixed only to the superior mesenteric‐portal vein confluence.

Extensive 2–3 cm segment of the superior mesenteric‐portal vein confluence may be resected without any need for interposition of a venous graft, if the splenic vein is cut. The venous resection is always performed with occlusion of the incoming through superior mesenteric vein blood flow and heparinization before its interruption. Upper gastrointestinal tract bleeding could be observed due to the left‐side portal hypertension after ligation of the splenic vein, inferior mesenteric vein, and left gastric veins. The mobilization of the neck of the pancreas frequently leads to ligation of the left gastric veins. If the blood flow of

**Figure 6.** Segmental resection of portal vein with T‐T venous anastomosis.

Shibata et al. divided SMV/PV resections into another four types being guided mainly from

It seems that the management of the splenic vein plays a crucial role during the reconstruc‐ tion of the SMV/PV confluence [31]. The classical technique of segmental venous resection includes transsection and ligation of the splenic vein. In technical aspect, this maneuver allows complete presentation of the superior mesenteric artery medially to the superior mes‐ enteric vein, and elongation of the superior mesenteric vein and portal vein (because the latter blood vessels are not adducted by the splenic vein) for performing of primary venous anasto‐ mosis after segmental venous resection. The retroperitoneal dissection ends with cutting by sharp manner of soft tissues anteriorly to the aorta and on the right side of the so presented superior mesenteric artery. As a result of that the specimen remains fixed only to the superior

Extensive 2–3 cm segment of the superior mesenteric‐portal vein confluence may be resected without any need for interposition of a venous graft, if the splenic vein is cut. The venous resection is always performed with occlusion of the incoming through superior mesenteric vein blood flow and heparinization before its interruption. Upper gastrointestinal tract bleeding could be observed due to the left‐side portal hypertension after ligation of the splenic vein, inferior mesenteric vein, and left gastric veins. The mobilization of the neck of the pancreas frequently leads to ligation of the left gastric veins. If the blood flow of

the localization of the resection line [30]:

**2.** Above the level of the splenic vein. **3.** Below the level of the splenic vein.

mesenteric‐portal vein confluence.

**Figure 6.** Segmental resection of portal vein with T‐T venous anastomosis.

**4.** Tangential resection.

204 Challenges in Pancreatic Pathology

**1.** Above and below the level of the splenic vein.

**Figure 7.** Segmental resection of SMV with T‐T reconstruction. Replaced right hepatic artery is pointed by the forceps.

the inferior mesenteric vein runs into the segment of the superior mesenteric vein, which is to be resected, the former vein must also be cut. Upon running of superior mesenteric vein into the splenic vein a way of collateral venous flow is ensured (after interruption of the splenic vein) in retrograde direction and the cutting of splenic vein in this situation is usually well tolerated. Of course, it is recommendable the splenic‐portal vein confluence to be preserved if possible, especially when ligation and cutting of inferior mesenteric vein is required. Preservation of the splenic vein is possible, only when the tumor invasion of the superior mesenteric vein or portal vein does not include the confluence with the splenic vein. Preservation of the splenic‐superior mesenteric‐portal vein confluence significantly limits the mobilization of the portal vein and preserves the primary anastomosis of supe‐ rior mesenteric vein (following segmental resection of superior mesenteric vein), except in cases when the segmental resection is limited up to 2 cm or less. On account of the latter an interpositional graft should be placed after resection of the superior mesenteric vein with preservation of splenic vein in most of the patients.

Reconstruction of portal vein and superior mesenteric vein after Cattel‐Braasch maneuver is usually possible without creating of considerable pressure on the venous anastomosis (**Figures 6** and **7**), at the same time the latter event could be avoided by implanting of a venous graft.

Segmental resection along a great extent of the porto‐mesenteric vein makes impossible the reconstruction with termino‐terminal anastomosis. In these cases a prosthesis (graft) is used, which may be an autologous one (most frequently internal jugular vein) or an artificial venous prosthesis.

Various types of autogenous veins have been used. Jugular, external iliac vein, great saphenous vein, left renal, and umbilical veins, as well as synthetic grafts could be used as substitutes for portal vein reconstruction. Fleming et al. reported that the superficial

**Figure 8.** Large resection of the portal vein with PTFE prosthesis replacement.

femoral vein is an excellent size‐matched conduit for reconstruction of the SMV or PV without serious complications associated with venous insufficiency in the leg [32]. The patency of reconstruction of the PV or SMV using superficial femoral vein (GSV) reported by Lee et al. was 88% at mean follow‐up of 5 months with only a few patients developing mild lower leg edema. Chiba University's team [33] first reported the use of a left renal vein graft for reconstruction of the portal vein. No obvious left kidney dysfunction has been diagnosed after the removal of left renal vein graft [34]. This technique has the fol‐ lowing advantages compared with other substitutes:


Chiba et al. reported a 100% patency rate in a cohort of 35 patients using a left renal vein graft for portal vein reconstruction, even at long‐term follow‐up. Suzuki et al. [34] also dem‐ onstrated that reconstruction of the inferior vena cava (IVC) or PV with the left renal vein is a durable and safe method without adverse effects on early and long‐term renal function. Other veins with smaller diameters like external jugular vein also could be used. The vein is customized by cutting longitudinally and suturing it into a sheet or tube‐like graft in order to overcome size discrepancy.

Its recommended synthetic grafts need to be avoided because many resections may involve contaminated bile and postoperative infectious complications could occur. On the other hand, the placement of autologous graft prolongs operative time, which is a prerequisite for postoperative complications. Use of artificial vascular prosthesis also bear risks from throm‐ bosis, as well as infectious complications, which is the main reason for it not to be preferred by most of the medical specialists, although it decreases up to the minimum by the time of clamping of the portal blood flow and is completely justified in critical situation, accord‐ ing to us (**Figure 8**). No difference is observed regarding the hepatic function and hemo‐ dynamics of the portal blood flow in the postoperative period, compared to other patients. Subacute or chronical thrombosis of the graft with the formation of collaterals are observed in long‐term follow‐up of patients with prosthesis of the porto‐mesenteric vein. This process, however, is of minor clinical significance, because it does not influence the liver function or the pressure on the system of portal vein. Recently, a multicenter analysis reported of synthetic graft reconstruction after portal vein resection in pancreaticoduodenectomy. The overall graft patency rate after 36 procedures was 76%. Portal vein thrombosis within 30 days after surgery occurred in 9.1%. Based on the data obtained from this study, it may be recommended that synthetic graft should not to be selected as a portal vein substitute if an autogenous vein graft is available. Synthetic graft could be used as an intraoperative tempo‐ rary portal vein shunt, followed by its removal after tumor excision combined with portal vein resection [35].
