Isolated caudate lobectomy with pancreatoduodenectomy for a bile duct cancer
In patients with distal bile duct cancer involving the hepatic hilus, a major hepatectomy concomitant with pancreatoduodenectomy (HPD) is sometimes ideal to obtain a cancer-free resection margin. However, the surgical invasiveness of HPD is considerable.
Patients and methods
We present our treatment option for patients with distal bile duct cancer showing mucosal spreading to the hepatic hilum associated with impaired liver function. To minimize resection volume of the liver, an isolated caudate lobectomy (CL) with pancreatoduodenectomy (PD) using an anterior liver splitting approach is presented. Liver transection lines and bile duct resection points correspond complete with our standard right and left hemihepatectomies with CL for perihilar cholangiocarcinoma.
Total operation time was 765 min, and pedicle occlusion time was 124 min, respectively. Although the proximal mucosal cancer extension was identified at both the right and the left hepatic ducts, all resection margins were negative for cancer.
Isolated CL with PD is an alternative radical treatment option for bile duct cancer patients with impaired liver function.
KeywordsCaudate lobectomyPancreatoduodenectomyBile duct cancerPerihilar cholangiocarcinoma
With recent advances in perioperative managements for perihilar cholangiocarcinoma (PCCa) including preoperative portal vein embolization and biliary drainage, major hepatobiliary resections become technically feasible and have been safer [1–5]. The clinical and oncological importance of caudate lobectomy (CL) in the surgical treatment for PCCa has been appreciable and established [6, 7]. In the majority of cases, CL is concomitantly performed during hemihepatectomy or trisectionectomy in a recent surgical series [8–16]. Liver parenchyma-preserving hepatectomy such as left medial sectionectomy or right anterior sectionectomy with CL for PCCa are technically complex and time-consuming surgical procedures; they are therefore considered only for limited or exceptional use in recent clinical settings [6, 17]. An isolated CL has been described as a surgical procedure for patients with bile duct cancer and hepatocellular carcinoma originated in the cirrhotic liver [18–20], and a technical description of isolated CL for bile duct cancer is rare .
On the other hand, major hepatectomy concomitant with pancreatoduodenectomy (HPD), indicated in patients with diffuse or longitudinally extended bile duct cancer, still remains critical and often jeopardizes patients with poor functional reserve of the liver [22–24]. It is a prime concern for a hepatobiliary surgeon to achieve a balance between the surgical stress and the oncological curability. We herein describe a technical report on an isolated CL with pancreatoduodenectomy (PD)  as a potential therapeutic option for a distal bile duct cancer extending up to the right and the left hepatic ducts in a patient with impaired functional reserve of the liver.
First of all, routine pancreatic head resection with a distal partial gastrectomy was performed. Next, skeletonization of the hepatoduodenal ligament was advanced up to the hepatic hilum, and all hepatic arteries should be deliberately skeletonized with autonomic nerve dissection. The cystic artery and the caudate lobe branch of the hepatic artery were ligated and divided. The left, middle, right anterior, and right posterior hepatic arteries were isolated. Caudate lobe branches of the portal vein were carefully ligated and divided, the umbilical portion of the left portal vein was exposed then mobilized, and the proximal end of the Arantius canal was ligated and divided. The right liver was mobilized and the caudate lobe was completely detached from the IVC; short hepatic veins were meticulously divided. The distal end of the Arantius canal was ligated and divided prior to liver parenchymal transection. The right and the common trunk of left (LHV) and middle (MHV) hepatic veins were encircled with tape.
Fundamentally, the liver parenchymal transection plane should trace along the course of the left side (medial section side) of the MHV. Liver parenchymal transection was performed using the Kelly clamp crushing method under intermittent inflow occlusion for 20 min at 5-min intervals. After division of a branch of V5 and a thick branch of V4, the left side aspect of MHV was clearly exposed to the confluence of the LHV. Liver transection was conducted to the most cranial part of the caudate lobe exposing the common trunk of the MHV and LHV. During this process, the liver transection approached the left side bile duct resecting point. After clamping the bile duct to prevent bile spillage as a potential cause of dissemination of cancer cells implicit in the bile, the right side intrahepatic bile duct was transected. We could identify the bile duct orifices, left medial sectional duct (B4), left lateral anterior segmental duct (B3), and left lateral posterior segmental duct (B2) from ventral to the dorsal direction in order.
After completing hemostasis, hepaticoplasty prior to bilio-enterostomy was performed to make a single orifice for the respective sides. At first, the left side hepaticoplasty for B2, 3, and 4 to make a single orifice for hepaticojejunostomy, similarly the right side hepaticoplasty for B5, 8a, 8c, and Bpost was performed. The proximal jejunal limb was pulled up to the hepatic hilum through the retrocolic route. And the left side bilio-enterostomy proceeded to the right side using interrupted sutures of 5–0 monofilament absorbable thread, and all four external biliary stents were placed across the bilio-enteric anastomosis for the respective sides (B2, B4, B5, and Bpost). At the proximal side of the hepaticojejunostomies, pancreatojejunostomy was made, then antecolic gastrojejunostomy was followed at approximately 40 cm anal side of the right side hepaticojejunostomies. Total operation time was 765 min, and pedicle occlusion time was 124 min, respectively. Intraoperative blood loss was 2,850 g.
Histologically, the tumor, moderately differentiated adenocarcinoma, extended to the pancreatic parenchyma, duodenal wall, and retropancreatic lymph node. Although the proximal mucosal cancer extension was documented at both the right anterior and left hepatic ducts, all surgical margins were negative for cancer. Pathological staging was T3N1M0, stage IIB in terms of AJCC 7th classification .
The postoperative clinical course was unremarkable, and the patient was discharged on the 26th postoperative day and is alive 13 months after the operation without any sign of tumor recurrence. The elevated CA19-9 level remains within the normal limit.
The performance of isolated CL is extremely restricted, and the actual number of PCCa treated by isolated CL is reported to be 10 or less , only a few cases in the recent surgical series [6, 8, 12, 13]. Thus, the technical issues and clinical role of isolated CL for bile duct cancer have not been thoroughly discussed. The caudate lobe is a difficult-to-approach anatomical location; the vascular structures including portal bifurcation, all hepatic arteries, all hepatic veins, and IVC should be preserved during the isolated CL. Despite recent advances in surgical techniques, an isolated CL still remains a complex and difficult procedure. On the other hand, while many patients with PCCa present with obstructive jaundice, their liver functional reserve can usually be restored sufficiently to allow major hepatectomy with CL in terms of preoperative biliary drainage. Moreover, CL is usually concomitantly performed as a part of hemi or more extended hepatectomy in the surgical treatment for PCCa due to the technical simplicity.
There are two different approaches to an isolated CL: one is high dorsal resection  and the other is the ALSA [18, 20, 21]. The purpose of CL for bile duct cancer is not removal of the liver parenchymal tissue, but en bloc resection of the biliary tree adjacent or belonging to the caudate lobe. From the oncological point of view, Shimada et al.  reported that liver parenchyma-preserving hepatectomy tended to result in higher frequencies of positive transmural margins. Miyazaki et al.  reported a beneficial role of parenchymal-preserving hepatectomy in patients with hilar cholangiocarcinoma that is localized at the hepatic duct confluence who do not require vascular resection, and high-risk patients with liver dysfunction. We modified the ALSA to cut the intrahepatic segmental bile ducts at the same point during our standard hemihepatectomies with CL. The two liver transection lines completely correspond to the right and left hemihepatectomies with CL for PCCa.
We usually do not touch the gallbladder during hemihepatectomy for PCCa to keep away from the hepatic hilum at the gallbladder neck for en bloc resection of the gallbladder and hilar plates. We consider traction of the gallbladder including the liver bed to facilitate counter traction of the transecting plane of the liver parenchyma. Even though the ALSA may take much more time, it can provide better operative views and larger working space for hepaticojejunostomy than a high dorsal resection. The piecemeal liver resection including liver bed aimed at an easier approach to transection of the border of liver parenchyma of the caudate lobe and resecting points of intrahepatic segmental bile ducts.
The ALSA in CL has also two ways in terms of the liver transecting plane, namely which side of the MHV is transecting? The right anterior section usually possesses larger liver volume and a larger number of thick hepatic venous tributaries than the left medial section. Thus, splitting the right side of MHV potentially causes a much more congested liver area than the left-side splitting. This liver congestion is noteworthy in the field of living donor-related liver transplantation , so we selected a left-side splitting approach to minimize liver congestion, which may potentially deteriorate remnant liver function.
Several predictive factors such as lymph node metastasis and perineural invasion affecting postoperative survival after surgery for bile duct cancer are reported [32–34]. Although in situ cancer invasion at the proximal bile duct margin does not have a strong impact on survival compared with a positive bile duct margin with invasive cancer [35, 36], needless to say, the resection with clear surgical margins is the ideal option for cure. Major HPD is one of the most delicate operations in terms of the degree of invasiveness, and often carries high morbidity and mortality rates. With improved perioperative management and surgical techniques, the short-term outcome for patients undergoing HPD has improved, but the current results are still unsatisfactory [22, 23]. Resected cases of biliary malignancies by HPD still remain few, so the future accumulation and analyses of HPD cases will delineate the patient profile with large benefit from this invasive operation [24, 37]. Selection of major HPD for patients with bile duct cancer must be decided with caution.
In our surgical managements for perihilar cholangiocarcinoma, we can calculate ICG-K of the future remnant liver (ICG-Krem) according to CT-volumetric analysis by multiplying the ICG-K value by the ratio of future remnant liver volume. The guiding value of ICG-Krem for a safe operation is 0.06, and a 0.05 is considered as the minimal requirement to tolerate major hepatobiliary resection in our current treatment strategy. Also, we take into consideration the hepatic functional reserve or invasiveness of the additional procedure with concomitant vascular resection and/or pancreatic head resection. In this case, ICG-K after the remission of jaundice ranged from 0.061 to 0.089 (median 0.078) during 5 weeks, thereby permissive liver resection volume was calculated from 1.6 to 32.5 % (median 23.0 %) to keep 0.06 of ICG-Krem. We finally judged an isolated CL was suitable and applicable procedure considering a concomitant pancreatic head resection for this particular patient.
In conclusion, our isolated CL, modified ALSA can provide similar proximal resection margins of intrahepatic segmental ducts to the hemihepatectomies. Although time-consuming and complex, this procedure can be applied in selected patients with impaired liver functional reserve. A good knowledge of the surgical anatomy and proficiency in hepatobiliary surgery are indispensable to perform an isolated CL.