Venous reconstruction based on virtual liver resection to avoid congestion in the liver remnant

Real-Time Blood Flow Assessment Using ICG Fluorescence Imaging During Hepatobiliary and Pancreatic Surgery with Consideration of Vascular Reconstruction

BACKGROUND/OBJECTIVES

Indocyanine green (ICG) fluorescence imaging is widely utilized for visualizing hepatic tumors, hepatic segmentation, and biliary anatomy, improving the safety and curability of cancer surgery. However, its application for perfusion assessment in hepatobiliary and pancreatic (HBP) surgery has been less explored.

METHODS

This study evaluated outcomes of patients undergoing HBP surgery with vascular reconstruction from April 2022 to August 2024. During surgery, ICG (1.25-5 mg/body) was administered intravenously to assess the need and quality of vascular reconstruction via fluorescence imaging.

RESULTS

Among 30 patients undergoing hepatectomies and/or pancreatectomies, ICG fluorescence imaging was used in 16 cases (53%) to evaluate organ and vascular perfusion. In two hepatectomy cases with consideration of reconstruction of the middle hepatic veins, sufficient fluorescence intensities in drainage areas led to the avoidance of middle hepatic vein reconstruction. In 14 cases requiring vascular reconstruction, fluorescence imaging visualized smooth blood flow through anastomotic sites in 11 cases, while insufficient signals were observed in 3 cases. Despite this, re-do anastomoses were not indicated because the fluorescence signals in the targeted organs were adequate. Postoperative contrast-enhanced computed tomography confirmed satisfactory blood perfusion in all cases.

CONCLUSIONS

Real-time blood flow assessment using ICG fluorescence imaging provides valuable information for intraoperative decision-making in HBP surgeries that require vascular reconstruction of major vessels, such as hepatic arteries, veins, and the portal system.

Prognostic Impact of Diabetes Mellitus and Extended Hepatectomy on Perihilar Cholangiocarcinoma

Objective

To evaluate the prognostic impact of diabetes mellitus (DM) in patients who underwent resection for perihilar cholangiocarcinoma (PHCC) and the influence of remnant liver volumes on postoperative glycemic profiles and survival outcomes.

Background

The impact of DM and extended hepatectomy on survival outcomes of patients with PHCC remains unclear.

Methods

A total of 184 patients who underwent hepatectomy with extrahepatic bile duct resection for PHCC between 2002 and 2020 were retrospectively analyzed and divided into groups based on DM and future liver remnant (FLR) ≥40% or <40%. Survival outcomes and glycemic profiles were analyzed.

Results

Patients with DM (n = 34) had significantly worse overall survival compared with those without DM (n = 150; median survival time: 23.3 vs 46.7 months; P = 0.003) although cancer-specific survival was comparable (P = 0.894). Patients with DM had a higher incidence of death from infections (P < 0.001). Multivariate analysis identified DM as an independent prognostic factor (hazard ratio, 1.742; P = 0.021). DM with FLR <40% (n = 11) exhibited worse survival (median survival time: 13.7 vs 35.0 months; P = 0.026) and a higher incidence of death from infections (P = 0.016) compared with those with FLR ≥40% (n = 23). The median glucose fluctuation was larger in patients with DM and FLR <40% (80 vs 39 mg/dL; P = 0.023).

Conclusions

DM was an independent prognostic factor in patients with PHCC undergoing hepatectomy. DM and FLR <40% were associated with worse survival and larger glucose fluctuation postoperatively.

Initial experience of parenchyma-sparing liver resection with systematic selective hepatic vein reconstruction for colorectal metastases

Objectives

This study aims to assess the feasibility and short-term and intermediate-term technical success rate of the concept of systematic selective hepatic vein (HV) reconstruction for parenchyma-sparing hepatectomies (PSHs) in patients with colorectal liver metastases (CRLM) in accordance with stage 2a of the IDEAL framework.

Design

The prospective case series of patients deemed eligible and operated on according to the concept.

Setting

All patients were treated by a single surgical team in three hospitals in Ukraine from June 2022 to November 2023.

Participants

The study included nine cases of resectable CRLM with at least one lesion located in the hepatocaval confluence with HV(s) invasion, for whom reconstruction of the HV(s) allowed for additional parenchyma preservation, being an alternative to major or extended hepatectomy.

Interventions

Liver resections with different types of HVs reconstruction (primary closure, patching, end-to-end anastomosis with or without grafting) were performed after a thorough evaluation of the future liver remnant volume, volume of potentially additionally preserved parenchyma and possibility of future repeat hepatectomies.

Main outcome measures

Postoperative morbidity, short-term and long-term patency of the reconstructed vessels, and the volume of additionally preserved parenchyma were the focus.

Results

Segmental resection was performed in four cases, two with graft interposition. Patch reconstruction was performed for three HVs and two inferior vena cava resections. Two cases required primary closure. No mortality was observed, while the major morbidity rate was 33%. The short-term and long-term patency of the reconstructed HVs was 88.9% and 66.7%, respectively. HV reconstructions allowed the preservation of additional parenchyma (mean 495.4 mL, 95% CI 350.2 to 640.7). A decision-making algorithm to be used within the described approach is proposed.

Conclusions

Selective HV reconstruction is a feasible approach for PSH for CRLM. Further studies are needed to compare this approach to convenient major hepatectomies.

Short- and long-term outcomes of liver resection with hepatic vein reconstruction for liver tumors: A nationwide multicenter survey

BACKGROUND/PURPOSE

This study clarifies the short- and long-term outcomes of liver resection with hepatic vein (HV) reconstruction for liver tumors and identifies the risk factors for poor outcome.

METHODS

We contacted 263 specialized centers in Japan and collected data on this surgical procedure. Patient characteristics, surgical procedures, and outcomes were then analyzed.

RESULTS

A total of 187 patients were enrolled from 36 institutions. Grade C post-hepatectomy liver failure (PHLF) and in-hospital mortality were 3.2% and 1.6%, respectively. The median overall survival (OS) and recurrence-free survival (RFS) were 49.9 and 9.8 months, respectively. Surgical outcomes, OS and RFS did not differ among three types of liver tumors, colorectal liver metastasis (CRLM) (n = 127), hepatocellular carcinoma (n = 27), and intrahepatic cholangiocarcinoma (n = 27). Patients with CRLM and seven or more courses of preoperative chemotherapy had significantly worse OS. Compared with HV reconstruction for securing liver remnant (LR) function (n = 148), reconstruction of the only main HV remaining in the LR (n = 39) had significantly worse short-term outcomes, but did not result in increased mortality, and showed equivalent OS and RFS.

CONCLUSIONS

Liver resection with HV reconstruction can be achieved safely and contributes to a relatively good long-term outcome for patients with advanced liver malignancies.

A Survey of Medical Visualization Through the Lens of Metaphors

We provide an overview of metaphors that were used in medical visualization and related user interfaces. Metaphors are employed to translate concepts from a source domain to a target domain. The survey is grounded in a discussion of metaphor-based design involving the identification and reflection of candidate metaphors. We consider metaphors that have a source domain in one branch of medicine, e.g., the virtual mirror that solves problems in orthopedics and laparoscopy with a mirror that resembles the dentist's mirror. Other metaphors employ the physical world as the source domain, such as crepuscular rays that inspire a solution for access planning in tumor therapy. Aviation is another source of inspiration, leading to metaphors, such as surgical cockpits, surgical control towers, and surgery navigation according to an instrument flight. This paper should raise awareness for metaphors and their potential to focus the design of computer-assisted systems on useful features and a positive user experience. Limitations and potential drawbacks of a metaphor-based user interface design for medical applications are also considered.

A Green Lantern for the Surgeon: A Review on the Use of Indocyanine Green (ICG) in Minimally Invasive Surgery

Indocyanine green (ICG) fluorescence imaging has revolutionized surgical practice across various medical and surgical specialties. This article reviews the clinical applications of ICG in abdominal, urological, thoracic, and gynecological surgery. ICG fluorescence imaging has been widely adopted in general surgery for various applications, including perfusion assessment, intraoperative visualization of the ureter, and tumor localization. It is particularly valuable in evaluating anastomotic leaks and aiding in precise tumor resection during minimally invasive surgeries. Studies have shown mixed results on its effectiveness in reducing anastomotic leak rates, highlighting the need for further research. In thoracic surgery, ICG facilitates the identification and resection of pulmonary bullae, as well as the precise localization of pulmonary nodules during video-assisted surgery. In urology, ICG aids in localizing renal tumors and guiding selective arterial occlusion during partial nephrectomy. Its role in identifying the lymphatic pathway in prostate cancer and sentinel lymph node biopsy in gynecological cancer is also discussed. Despite its benefits, the use of ICG fluorescence faces challenges such as limited tissue penetration, the potential for false results, a lack of standardized protocols, and high equipment costs. Nonetheless, it remains a powerful tool that could improve surgical outcomes.

Reproducibility and efficiency of liver volumetry using manual method and liver analysis software

BACKGROUND

For liver volumetry, manual tracing on computed tomography (CT) images is time-consuming and operator dependent. To overcome these disadvantages, several three-dimensional simulation software programs have been developed; however, their efficacy has not fully been evaluated.

METHODS

Three physicians performed liver volumetry on preoperative CT images on 30 patients who underwent formal right hepatectomy, using manual tracing volumetry and two simulation software programs, SYNAPSE and syngo.via. The future liver remnant (FLR) was calculated using each method of volumetry. The primary endpoint was reproducibility and secondary outcomes were calculation time and learning curve.

RESULTS

The mean FLR was significantly lower for manual volumetry than for SYNAPSE or syngo.via; there was no significant difference in mean FLR between the two software-based methods. Reproducibility was lower for the manual method than for the software-based methods. Mean calculation time was shortest for SYNAPSE. For the two physicians unfamiliar with the software, no obvious learning curve was observed for using SYNAPSE, whereas learning curves were observed for using syngo.via.

CONCLUSIONS

Liver volumetry was more reproducible and faster with three-dimensional simulation software, especially SYNAPSE software, than with the conventional manual tracing method. Software can help even inexperienced physicians learn quickly how to perform liver volumetry.

Novel Use of the Falciform Ligament for MHV Reconstruction During Laparoscopic Hepatectomy of Colorectal Liver Metastasis

BACKGROUND

Laparoscopic hepatectomy (LH) with oncological R0 resection combined with systemic therapy offers the best chance of cure for colorectal liver metastasis. However, tumors in vicinity of major hepatic veins require complex technique. Parenchyma-sparing resection with involved vein resection and peritoneal patch reconstruction could be an efficacious alternative to preserve liver volume for adjuvant chemotherapy and avoid venous congestion of the remnant liver.1,2 METHODS: A 64-year-old female, with history of colon cancer, had new diagnosis of liver metastatic tumor of S8 (2.8 cm), which was considering encroached on middle hepatic vein (MHV) with distal part patent. Thus margin-negative, parenchyma-sparing liver resection with involved vein resection and proximal MHV reconstruction was indicated for oncological radicality.

RESULTS

With the patient in modified French position, we dissected falciform ligament and right coronary ligament to expose the crypt between right hepatic vein (RHV) and MHV. Intraoperative ultrasound localized the tumor and resection margin. Parenchymal dissection was performed caudally to cranially, left to right, to ligate dorsal branch of G8 (G8d) and V8 and expose main trunk of MHV. The involved side-wall of MHV was incised after the proximal and distal parts clamped. Peritoneal patch was harvested from falciform ligament to repair MHV side-wall before clamps released. The patient had an uneventful recovery and remained disease-free at 1 year postoperatively with patency of distal MHV by image.

CONCLUSIONS

LH with MHV reconstruction by falciform ligament for metastatic lesion is technically demanding but feasible with oncological radicality and volume preservation for adjuvant chemotherapy.

Conditional recurrence analysis of intrahepatic cholangiocarcinoma: Changes in recurrence rate and survival after recurrence resection by disease-free interval

AIM

The prognosis of patients with resected intrahepatic cholangiocarcinoma (ICC) is still unsatisfactory, with a high recurrence rate. We aimed to evaluate risks of recurrence changing over time and the survival benefit of resection for recurrent ICC.

METHODS

This study included patients who underwent hepatectomy for ICC during 1995-2020. Risk factors for recurrence-free survival (RFS) in patients undergoing initial resection and overall survival (OS) in patients who developed recurrence after initial resection were analyzed. Conditional cumulative incidence of recurrence was assessed.

RESULTS

A total of 169 patients were included in the study and 114 patients (67.5%) developed recurrence. Cumulative analyses showed that the 5-year recurrence rate was 69.3% at the time of initial resection but decreased to 24.8% in patients free from recurrence at 2 years after initial resection and 2.6% in patients free from recurrence at 4 years. Re-resection was carried out in 26 (22.8%) of 114 patients who developed recurrence. Multivariable Cox proportional hazards model analysis indicated re-resection (hazard ratio [HR] 0.19; 95% confidence interval [CI] 0.11-0.40, p < 0.001), microvascular invasion (MVI) (HR 2.39; 95% CI 1.05-5.40, p = 0.037), and disease-free interval (months) (HR 0.97; 95% CI 0.95-1.00, p = 0.067) were significantly associated with longer OS after recurrence.

CONCLUSIONS

Although the rate of recurrence remains high, conditional cumulative recurrence rate analysis showed that the rate of recurrence decreased by disease-free interval. Resection of recurrent ICC was associated with improved OS, particularly among patients with longer disease-free interval and absence of MVI after initial hepatectomy.

Objective Definition and Optimized Strategy for "Biologically Borderline Resectable" Colorectal Liver Metastases

BACKGROUND

The prognostic benefit of preoperative chemotherapy leading to conversion surgery for unresectable colorectal liver metastases (CRLM) is well recognized, while that of neoadjuvant chemotherapy (NAC) compared with upfront surgery (UFS) for resectable CRLM is negligible. This study aims to assess the prognostic benefit and search for optimal indication of NAC for resectable advanced CRLM by establishing an objective definition of biologically borderline resectable (bBR) CRLM.

METHODS

A bicentric retrospective analysis of patients with CRLM undergoing curative-intent initial liver resection between 2007 and 2021 was performed. An original classification matrix was established, which reassessed technical resectability using virtual hepatectomy and oncological favorability using Beppu's nomogram. Patients with technically resectable but biologically unfavorable CRLM were classified into the bBR group. The propensity score matching analysis using preoperatively available factors was performed to assess long-term outcomes of the bBR-UFS and bBR-NAC groups.

RESULTS

Of 831 patients reviewed, 240 were categorized into the bBR group: bBR -UFS (n = 139) and bBR-NAC (n = 101). Ten (10%) in the bBR-NAC group (n = 101) experienced biological status change from unfavorable to favorable after NAC (Biological Conversion) and showed significantly longer overall survival (hazard ratio 5.63, 95% confidence interval 1.37-23.1; P = 0.016) than the bBR-UFS group. However, after propensity score matching, no significant difference between the UFS and NAC groups (n = 67 for each) was found in long-term outcomes.

CONCLUSIONS

NAC for bBR-CRLM did not enhance the prognostic impact of the following liver resection, except for a limited number of optimal candidates experiencing the Biological Conversion.

[Transplantation technologies in pediatric liver resections]

Liver resections with transplantation technologies have been recognized as safe procedures for the last decades. These procedures may be the only curative option or alternative to liver transplantation in some cases. Moreover, these surgeries can also provide parenchyma-sparing liver resection. Nevertheless, higher postoperative morbidity and mortality compared to traditional hepatectomy require careful research of indications for liver resections with transplantation technologies, the role of vascular liver exclusion, methods of vascular reconstructions with or without anticoagulation. These challenges are more important for pediatric surgery due to few literature data on this issue. This review is devoted to liver resections with transplantation technologies.

Automated Three-Dimensional Liver Reconstruction with Artificial Intelligence for Virtual Hepatectomy

OBJECTIVE

To validate the newly developed artificial intelligence (AI)-assisted simulation by evaluating the speed of three-dimensional (3D) reconstruction and accuracy of segmental volumetry among patients with liver tumors.

BACKGROUND

AI with a deep learning algorithm based on healthy liver computer tomography images has been developed to assist three-dimensional liver reconstruction in virtual hepatectomy.

METHODS

3D reconstruction using hepatic computed tomography scans of 144 patients with liver tumors was performed using two different versions of Synapse 3D (Fujifilm, Tokyo, Japan): the manual method based on the tracking algorithm and the AI-assisted method. Processing time to 3D reconstruction and volumetry of whole liver, tumor-containing and tumor-free segments were compared.

RESULTS

The median total liver volume and the volume ratio of a tumor-containing and a tumor-free segment were calculated as 1035 mL, 9.4%, and 9.8% by the AI-assisted reconstruction, whereas 1120 mL, 9.9%, and 9.3% by the manual reconstruction method. The mean absolute deviations were 16.7 mL and 1.0% in the tumor-containing segment and 15.5 mL and 1.0% in the tumor-free segment. The processing time was shorter in the AI-assisted (2.1 vs. 35.0 min; p < 0.001).

CONCLUSIONS

The virtual hepatectomy, including functional liver volumetric analysis, using the 3D liver models reconstructed by the AI-assisted methods, was reliable for the practical planning of liver tumor resections.

Uses of a dedicated 3D reconstruction software with augmented and mixed reality in planning and performing advanced liver surgery and living donor liver transplantation (with videos)

The development of digital intelligent diagnostic and treatment technology has opened countless new opportunities for liver surgery from the era of digital anatomy to a new era of digital diagnostics, virtual surgery simulation and using the created scenarios in real-time surgery using mixed reality. In this article, we described our experience on developing a dedicated 3 dimensional visualization and reconstruction software for surgeons to be used in advanced liver surgery and living donor liver transplantation. Furthermore, we shared the recent developments in the field by explaining the outreach of the software from virtual reality to augmented reality and mixed reality.

Influence of middle hepatic vein resection during right or left hepatectomy on post hepatectomy outcomes

BACKGROUNDS/AIMS

Middle hepatic vein (MHV) is usually preserved as a part of the right or left hepatectomy in order preserve the venous outflow of remnant liver. The aim of this study was to evaluate if resection of MHV could influence post-resection outcomes of standard right or left hepatectomy.

METHODS

Patients who underwent standard right or left hepatectomy between January 2015 and December 2019 were included. Anatomical remnant liver volumes were measured retrospectively using the Hermes workstation (Hermes Medical Solutions AB, Stockholm, Sweden). Uni- and multi-variate analyses were performed to assess the difference in outcomes of those with preservation of MHV and those without preservation.

RESULTS

A total of 144 patients were included. Right hepatectomy was performed for 114 (79.2%) and left hepatectomy was performed for 30 (20.8%) patients. MHV was resected for 13 (9.0%) in addition to the standard right or left hepatectomy. Median remnant liver volume was significantly higher in the MHV resected group (p < 0.01). There was no significant difference in serum level of bilirubin, international normalized ratio, alanine aminotransferase, creatinine on postoperative day 1, 3, 5, or 10, ≥ grade IIIa complications (p = 0.44), or 90-day mortality (p = 0.41). On multivariable analysis, resection of the MHV did not influence the incidence of post hepatectomy liver failure (p = 0.52).

CONCLUSIONS

Resection of the MHV at standard right or left hepatectomy did not have a negative impact on postoperative outcomes of patients with adequate remnant liver volume.

Added value of indocyanine green fluorescence imaging in liver surgery

Recently, indocyanine green (ICG) fluorescence imaging has been widely used as a substitute for cholangiography in hepatobiliary surgery, to detect hepatic tumors, for accurate anatomical hepatectomy, and to increase the safety and accuracy of minimally invasive (laparoscopic and robotic) hepatectomy. The clinical relevance of this method has been increasing gradually, as new procedures develop in this field. Various important roles and the latest added value of ICG fluorescence imaging in liver surgery are discussed in this report.

First Robotic Hepatectomy With Middle Hepatic Vein Reconstruction Using ePTFE Graft for Hepatic Adenoma: A Case Report

Surgical resection remains the best choice for the treatment of liver tumors. Hepatectomy combined with artificial vascular reconstruction has been proven as an alternative to treating tumors involving the main hepatic veins. As the cutting-edge surgical technique, robotic liver surgery is a novel procedure expanding the field of minimally invasive approaches, especially in complex reconstruction. This study reports, for the first time, on a robotic hepatectomy with middle hepatic vein (MHV) reconstruction using an expanded polytetrafluoroethylene (ePTFE) graft for a patient with hepatic adenoma. The tumor, which was located in segment 8, was adjacent to the MHV. Robot-assisted resection of segment 4 and partial segment 8, and MHV reconstruction using a ePTFE graft were performed. During the post-operative examination and follow-up, the blood flow of the ePTFE graft was patent, and liver function recovered well. Thus, robotic hepatectomy with MHV reconstruction is a safe, minimally invasive, and precise surgery that may provide a novel approach for patients with liver tumors that are invading or adjacent to the main hepatic veins.

Surgical relevance of anatomic variations of the right hepatic vein

BACKGROUND

Variations in the anatomy of hepatic veins are of interest to transplant surgeons, interventional radiologists, and other medical practitioners who treat liver diseases. The drainage patterns of the right hepatic veins (RHVs) are particularly relevant to transplantation services.

AIM

The aim was to identify variations of the patterns of venous drainage from the right side of the liver. To the best of our knowledge, there have been no reports on RHV variations in in a Caribbean population.

METHODS

Two radiologists independently reviewed 230 contrast-enhanced computed tomography scans performed in 1 year at a hepatobiliary referral center. Venous outflow patterns were observed and RHV variants were described as: (1) Tributaries of the RHV; (2) Variations at the hepatocaval junction (HCJ); and (3) Accessory RHVs.

RESULTS

A total of 118 scans met the inclusion criteria. Only 39% of the scans found conventional anatomy of the main hepatic veins. Accessory RHVs were present 49.2% and included a well-defined inferior RHV draining segment VI (45%) and a middle RHV (4%). At the HCJ, 83 of the 118 (70.3%) had a superior RHV that received no tributaries within 1 cm of the junction (Nakamura and Tsuzuki type I). In 35 individuals (29.7%) there was a short superior RHV with at least one variant tributary. According to the Nakamura and Tsuzuki classification, there were 24 type II variants (20.3%), six type III variants (5.1%) and, five type IV variants (4.2%).

CONCLUSION

There was significant variation in RHV patterns in this population, each with important relevance to liver surgery. Interventional radiologists and hepatobiliary surgeons practicing in the Caribbean must be cognizant of these differences in order to minimize morbidity during invasive procedures.

Simulation of portal/hepatic vein associated remnant liver ischemia/congestion by three-dimensional visualization technology based on preoperative CT scan

Background

Remnant liver hypoperfusion is frequently observed after hepatectomy, and associated with a higher risk of postoperative complications and poorer survival. However, the development of remnant liver hypoperfusion was not fully understood.

Methods

We retrospectively analyzed patients who received hepatectomy and took contrast-enhanced computed tomography (CT) scans before, 1-week (POW1) and 4-week (POW4) after resection in our department from June 2017 to July 2019. We simulated and estimated the occurrence of portal-vein-related remnant liver ischemia (RLI) and hepatic-vein-related remnant liver congestion (RLC) after hepatectomy via three-dimensional visualization technology (3DVT) according to blood vessels ligated in the resection; then we analyzed association between the estimated RLI, RLC, and postoperative clinical outcomes.

Results

A total of 102 eligible patients were analyzed. Remnant liver hypoperfusion was observed in 47 (46%) patients in the POW1 CT scans and shrunk in the POW4 CT scans. RLC had better diagnostic significance than RLI in predicting remnant liver hypoperfusion [area under receiver operating characteristic (ROC) curve: 0.745 vs. 0.569, P=0.026]. Multivariate analysis showed that larger RLI [odds ratio (OR), 1.154; 95% confidence interval (CI), 1.075-1.240; P<0.001] was independent risk factor for post-hepatectomy liver failure (PHLF). Besides, larger RLC (OR, 1.114; 95% CI, 1.032-1.204; P=0.006) was independent risk factor for major postoperative complications.

Conclusions

Remnant liver hypoperfusion can be predicted during the preoperative surgical plan by 3DVT. Portal vein related RLI was associated with PHLF, and hepatic vein related RLC was associated with major postoperative complications. Preservation of the hepatic vein and complete removal of the perfusion territory of ligated vessels are essential procedures to reduce RLI/RLC and the risk of PHLF or other surgical complications.

Preserving inferior right hepatic vein enabled bisegmentectomy 7 and 8 without venous congestion: a case report

BACKGROUND

In hepatectomy, the preservation of portal perfusion and venous drainage in the remnant liver is important for securing postoperative hepatic function. Right hepatectomy is generally indicated when a hepatic tumor involves the right hepatic vein (RHV). However, if a sizable inferior RHV (IRHV) exists, hepatectomy with preservation of the IRHV territory may be another option. In this case, we verified the clinical feasibility of anatomical bisegmentectomy 7 and 8 with RHV ligation, averting the right hepatic parenchyma from venous congestion, utilizing the presence of the IRHV.

CASE PRESENTATION

A 70-year-old man was presented with a large hepatic tumor infiltrating the RHV on computed tomography during a medical checkup. The patient was diagnosed with hepatocellular carcinoma (HCC), T2N0M0, stage III. Right hepatectomy was first considered, but multi-detector computed tomography (MDCT) also revealed a large IRHV draining almost all of segments 5 and 6, suggesting that IRHV-preserving liver resection may be another option. The calculated future remnant liver volumes were 382 mL (26.1% of the total volume) after right hepatectomy and 755 mL (51.7% of the total volume) after anatomical bisegmentectomy 7 and 8; therefore, we scheduled IRHV-preserving anatomical bisegmentectomy 7 and 8 considering the prevention of postoperative liver failure and increased chance of performing repeat resections in cases of recurrence. Preoperative three-dimensional simulation using MDCT clearly revealed the portal perfusion area and venous drainage territories by the RHV and IRHV. There was an issue with invisibility of the anatomical resection line of segments 7 and 8, which was completely dissolved by intraoperative ultrasonography using Sonazoid and the portal dye injection technique with counter staining. The postoperative course in the patient was uneventful, without recurrence of HCC, for 30 months after hepatectomy.

CONCLUSIONS

IRHV-preserving anatomical bisegmentectomy 7 and 8 is a safe and feasible procedure utilizing the three-dimensional simulation of the portal perfusion area and venous drainage territories and the portal dye injection technique.

Bisegmentectomy and venous reconstruction after portal vein embolization for the remnant hemiliver in a patient with recurrent colorectal liver metastases

Repeat hepatectomy for recurrent colorectal liver metastases (CRLM) for the remnant hemiliver is sometimes challenging due to the insufficient future liver remnant (FLR) volume. We present an aggressive strategy for resection of the recurrent CRLM involving bisegmentectomy of the remnant right hemiliver with the aid of portal vein embolization (PVE) and venous reconstruction. The patient was a 50-year-old woman who had undergone left hemihepatectomy for a CRLM 10 months ago. Three metastatic tumors were found in the remnant segments 7 and 8 (S7&8) of the liver, and one of them involved the right hepatic vein (RHV). Conducting bisegmentectomy of S7&8 with resection of the RHV, the non-congestive FLR volume was calculated as 34.9% of the remnant total liver volume, which was deemed insufficient considering the mild liver damage after repeated chemotherapy. After trans-ileocecal PVE of the portal branches in S7&8 in a hybrid angio room, the non-congestive FLR volume increased to 42.3%, which could be further advanced to 58.0% if the RHV was reconstructed. Segmentectomies of S7&8 with resection and reconstruction of the RHV using the right superficial femoral vein graft was performed. The patient was discharged without any complications, and the postoperative computed tomography (CT) scan showed the good patency of the reconstructed venous graft. Aggressive segmentectomies and venous reconstruction of the remnant hemiliver after PVE might be a new strategy to overcome the insufficient FLR volume.

Reconstruction of the middle hepatic vein using a vein graft from the resected portion of the liver

Background

The middle hepatic veins are often infiltrated by intrahepatic cholangiocarcinoma. Reconstruction of the hepatic vein plays a critical role in preserving more of the residual liver volume and reducing the risk of postoperative liver failure in extreme hepatectomy. We here report a novel way to reconstruct middle hepatic vein by using vessel grafts from wasted liver.

Case presentation

Case 1: A 64-year-old man was diagnosed with intrahepatic cholangiocarcinoma. The bifurcation and left branch of the portal vein were stenosed, and the root of the middle hepatic vein was infiltrated by the tumor. An extended left hepatectomy was performed, the portal vein was resected and reconstructed, and the middle hepatic vein was reconstructed by anastomosing the proximal left hepatic vein to the distal middle hepatic vein. Case 2: A 69-year-old woman was diagnosed with intrahepatic cholangiocarcinoma. The tumor was located in the left lobe of the liver and the left and middle hepatic veins were infiltrated by the tumor. An extended left hepatectomy was performed, and the left portal vein was used as a vein graft to reconstruct the middle hepatic vein. Both of the two patients’ postoperative ultrasound showed vessel graft patency.

Conclusion

Using a vein graft from the resected portion of the liver to reconstruct the middle hepatic vein was a useful technique and showed good result.

Simulation and navigation liver surgery: an update after 2,000 virtual hepatectomies

The advent of preoperative 3-dimensional (3D) simulation software has made a variety of unprecedented surgical simulations possible. Since 2004, we have performed more than 2,000 preoperative simulations in the University of Tokyo Hospital, and they have enabled us to obtain a great deal of information, such as the detailed shape of liver segments, the precise volume of each segment, and the volume of hepatic venous drainage areas. As a result, we have been able to perform more aggressive and complicated surgery safely. The next step is to create a navigation system that will accurately reproduce the preoperative plan. Real-time virtual sonography (RVS) is a navigation system that provides fusion images of ultrasonography and reconstructed computed tomography images or magnetic resonance images. The RVS system facilitates the surgeon's understanding of interpretation of ultrasound images and the detection of tumors that are difficult to find by ultrasound alone. In the near future, surgical navigation systems may evolve to the point where they will be able to inform surgeons intraoperatively in real time about not only intrahepatic structures, such as vessels and tumors, but also the portal territory, hepatic vein drainage areas, and resection lines that have been planned preoperatively.

Validation of Functional Assessment for Liver Resection Considering Venous Occlusive Area after Extended Hepatectomy

BACKGROUND

Previous studies demonstrated that liver function in a veno-occlusive region is approximately 40% of that in a non-veno-occlusive region after hepatectomy with excision of major hepatic vein. We validated the preoperative assessment of future remnant liver (FRL) function based on 40% decreased function of the veno-occlusive region.

METHODS

Sixty patients who underwent hepatectomy with excision of major hepatic vein were analyzed. The FRL functions of the veno-occlusive and non-veno-occlusive regions were calculated with 99mTc-galactosyl human serum albumin scintigraphy single-proton emission computed tomography fusion system and SYNAPSE VINCENT® preoperatively. Risk assessment for hepatectomy was evaluated based on indocyanine green retention at 15 min, and patients with insufficient FRL function were described as marginal.

RESULTS

The median volume and function of the veno-occlusive region per whole liver were 111 ml and 11.0%, respectively. When the function of the veno-occlusive region was presumed as 0%, 40%, and 100%, the FRL function was 62.5%, 68.4%, and 75.0% and 21, 15, and 7 patients were classified as marginal, respectively. When the function of the veno-occlusive region was presumed as 40%, the posthepatectomy liver failure (PHLF) rate of marginal patients was significantly higher than that of safe patients (46.7% vs 8.9%, P = 0.002). Multivariable analysis indicated that marginal FRL function based on 40% decreased function of the veno-occlusive region was the only independent risk factor for PHLF (odds ratio 8.97, P = 0.002) after extended hepatectomy.

CONCLUSION

Assessment of preoperative FRL function based on 40% decreased function of the veno-occlusive region may have high validity.

Successful use of the left portal vein as graft for middle hepatic vein reconstruction in left hemihepatectomy: preliminary experience on six cases

BACKGROUND

The purpose of this research was to assess the feasibility of reconstructing the middle hepatic vein (MHV) with resected left portal vein during left hemihepatectomy.

METHODS

From January 2014 to January 2018, six patients received left hemihepatectomy combined with MHV reconstruction using the resected left portal vein in West China Hospital. We reviewed the clinical data including patient details, surgical technique, graft patency, and operative results.

RESULTS

All six patients underwent left hemihepatectomy for liver tumors located at left hepatocaval confluence. In these patients, MHV was resected due to tumor invading and reconstructed using the resected left portal vein as graft. The mean operating time was 316 min. Two patients developed complications: one experienced bile leakage and one experienced pleural effusion. No patient developed vascular graft complications. All the grafts remained unobstructed, and no local tumor recurrence occurred during the observation period of 13-41 months.

CONCLUSIONS

Our results indicated that the left portal vein was a safe graft for hepatic vein reconstruction. In addition, left hemihepatectomy combined with middle hepatic vein resection and reconstruction using the left portal vein can be performed safely to treat liver tumors located at hepatocaval confluence.

Practical Contribution of Virtual Hepatectomy for Colorectal Liver Metastases: a Propensity-Matched Analysis of Clinical Outcome

BACKGROUND

Recent improvements in imaging technologies have enabled surgeons to perform precise planning using virtual hepatectomy (VH). However, the practical and clinical benefits of VH remain unclear. This study sought to assess how three-dimensional analysis using a VH contributed to preoperative planning and postoperative outcome in patients undergoing liver surgery for the treatment of colorectal liver metastases (CRLM).

METHODS

From 2007 to 2017, a total of 473 CRLM patients who received curative hepatectomy were retrospectively assessed. A 1:1 matched propensity analysis was performed between patients who did not receive a VH (without 3D group: n = 188) and received a VH (3D(+) group: n = 285).

RESULT

The rate of VH increased over the study period (P < 0.001). After propensity score matching (n = 150 for each group), no significant differences were observed in the intraoperative and postoperative outcome, including liver transection time, blood loss, or morbidity between the groups. More patients received a small anatomical resection (plus limited resections) in the 3D(+) group (25 vs 11%, [P = 0.03]). A submillimeter margin was less frequent in the 3D(+) group. No significant differences in the 5-year overall survival and disease-free survival rates were seen between the without 3D group and the 3D(+) group (38.0 vs. 45.9% [P = 0.99], 11.1 vs. 21.7%, respectively [P = 0.109]).

CONCLUSION

Although VH did not significantly influenced on the long-term outcome after hepatectomy, a more parenchymal-sparing operative procedure (anatomical resections, plus limited resections) was selected and the risk of a submillimeter surgical margin was reduced after introduction of VH.

Post hepatectomy liver failure - A comprehensive review of current concepts and controversies

Post hepatectomy liver failure (PHLF) comprises of a conundrum of symptoms and signs following major hepatic resections. The pathophysiology essentially revolves around disruption of the normal hepatocyte regeneration and disturbed liver homeostasis. Prompt identification of the pre-operative predictors of PHLF in the form of biochemical parameters and imaging features are of paramount importance for any hepatic surgeon and forms the cornerstone of its management. Treatment revolves around a goal-directed resuscitation of the systemic organ failure. Auxiliary support systems such as liver dialysis devices and stem cell therapy are still under investigational trials for treatment of the same. Orthotopic liver transplantation (OLT) is the last resort in most cases not responding to other measures.

Feasibility of Intraoperative Navigation for Liver Resection Using Real-time Virtual Sonography With Novel Automatic Registration System

BACKGROUND

The clinical feasibility and usability of intraoperative ultrasonography (IOUS) tracked by computed tomography (CT) images have been proposed; however, it requires technically demanding manual registration procedure.

STUDY DESIGN

A prospective study using real-time virtual sonography (RVS) with novel automatic registration system was conducted in four high-volume centers of liver resection from 2015 to 2016. The requiring time for registration of IOUS and CT images and positional error of confluence of middle hepatic venous tributaries (V8-MHV, V5-MHV) were measured in patients undergoing laparotomy.

RESULTS

Automatic registration was successful in 43 of 52 enrolled patients (83%), with error ranges of 11.4 (3.1-69.4) mm for V8-MHV and 16.2 (4.3-66.8) mm for V5-MHV. Time required for total registration process was 36 (27-74) s.

CONCLUSIONS

The RVS with novel automatic registration system can provide quick and easy registration and acceptable accuracy, which can promote the usage of IOUS.

How Has Virtual Hepatectomy Changed the Practice of Liver Surgery?: Experience of 1194 Virtual Hepatectomy Before Liver Resection and Living Donor Liver Transplantation

OBJECTIVE

To assess how virtual hepatectomy (VH), conducted using surgical planning software, influences the outcomes of liver surgery.

BACKGROUND

Imaging technology visualizes the territories of the liver vessels, which were previously impossible. However, the clinical impact of VH has not been evaluated.

METHODS

From 2004 to 2013, we performed 1194 VHs preoperatively. Outcomes of living donor liver transplantation (LDLT) and hepatectomy for hepatocellular carcinoma (HCC)/colorectal liver metastases (CRLM) were compared between patients in whom VH was performed (VH) and those without VH evaluation (non-VH).

RESULTS

In LDLT, the rate of right liver graft use was higher in the VH (62.1%) than in the non-VH (46.5%) (P < 0.01), which did not increase morbidity of donor surgery. Duration of recipient surgery in the VH in which middle hepatic vein branch reconstruction was skipped was shorter than that in the VH with venous reconstruction. Among HCC patients with impaired liver function, portal territory-oriented resection was conducted more often in the VH than in the non-VH. The 5-year disease-free survival rate for localized HCC was higher in the VH than in the non-VH (37.2% vs 23.9%; P = 0.04). In CRLM, long-term outcomes were similar in the VH and non-VH despite the larger tumor load in the VH.

CONCLUSIONS

VH in LDLT allows double equipoise for the recipient and donor by optimizing decision-making on graft selection and venous reconstruction. VH offers a chance for radical hepatectomy even in HCC patients with impaired liver function and CRLM patients with advanced tumors, without compromising survival.

Two-stage hepatectomy aiming for the development of intrahepatic venous collaterals for multiple colorectal liver metastases

Background

Aggressive hepatectomy with venous resection has a higher risk of postoperative liver failure (POLF) than hepatectomy without venous reconstruction; however, venous reconstruction is technically demanding. We performed a novel two-stage hepatectomy (TSH) without venous reconstruction in a patient with bilobar multiple colorectal liver metastases located near the caval confluence, waiting for the development of intrahepatic venous collaterals between procedures.

Case presentation

A 60-year-old man was referred to our hospital with sigmoid colon cancer accompanied by intraabdominal abscess and two synchronous liver metastases. One of the liver tumors (tumor 1) was located in segment 8 near the caval confluence and was attached to both the right hepatic vein (RHV) and middle hepatic vein (MHV). The other tumor (tumor 2) in the left lobe invaded the umbilical portion of the portal vein. Both liver metastases decreased in size after four cycles of panitumumab/5-fluorouracil, leucovorin, and oxaliplatin (FOLFOX) therapy. Radical liver resection was planned because tumor 1 had not invaded the MHV. However, three-dimensional volumetric software showed that the non-congested volume of the future liver remnant was estimated at 354 ml, which corresponded to 26.3% of the total liver volume. TSH was scheduled to avoid POLF. We first performed limited resection of segment 8 with resection of the RHV root. After the first hepatectomy, the development of intrahepatic venous collaterals between the RHV and MHV was seen on computed tomography and magnetic resonance imaging. The estimated non-congested future liver remnant was 1242 ml, 78.5% of the total liver volume. Therefore, the patient underwent left hemihepatectomy 58 days after the first hepatectomy. We saw no adhesions around the porta hepatis, and the left hepatic artery and left branch of the portal vein were safely exposed and divided. Intraoperative Doppler ultrasonography revealed intrahepatic venous collaterals arising from RHV to MHV. The patient’s postoperative course was uneventful, and he underwent eight cycles of panitumumab/FOLFOX therapy for 5 months after the second hepatectomy.

Conclusions

Our TSH strategy helped avoid POLF by waiting for the development of intrahepatic venous collaterals.

Safety and efficacy of venous reconstruction in liver resection using cryopreserved homologous veins

BACKGROUND

Only a few studies have reported the resection and reconstruction of major hepatic veins during hepatectomy. Here, we present our strategy and techniques for venous reconstruction with cryopreserved homologous veins, and describe the surgical outcome.

METHODS

Among 2,387 hepatectomy patients, 39 patients who required hepatic venous reconstruction were reviewed retrospectively. Venous reconstruction was performed to secure a non-congested liver remnant volume of at least 40% of the total liver volume.

RESULTS

There was no operative mortality, and the severe morbidity rate was 5% in this series. A total of 41 veins were reconstructed; 30 with homologous veins (73.2%) and 11 with autologous veins (26.8%), with the middle hepatic vein being the most frequent (n = 23, 56%). Interposition grafting was performed more often (P = 0.003), the length of the venous resection was longer (P = 0.007), and pathologic wall infiltration of the vein was revealed more often (P = 0.002) in the homologous graft group than in the autologous graft group. The 1-, 2-, and 3-year overall patency of the reconstructed veins was 55.4%, 46.3%, and 46.3%, respectively.

CONCLUSIONS

Aggressive venous reconstruction during hepatectomy using cryopreserved homologous veins is a feasible option with satisfactory short-term outcomes, and may be warranted to improve operative safety.

Liver transection using indocyanine green fluorescence imaging and hepatic vein clamping

BACKGROUND

Three-dimensional (3D) imaging has facilitated liver resection with excision of hepatic veins by estimating the liver volume of portal and hepatic venous territories. However, 3D imaging cannot be used for real-time navigation to determine the liver transection line. This study assessed the value of indocyanine green (ICG) fluorescence imaging with hepatic vein clamping for navigation during liver transection.

METHODS

Consecutive patients who underwent liver resection with excision of major hepatic veins between 2012 and 2013 were evaluated using ICG fluorescence imaging after clamping veins and injecting ICG. Regional fluorescence intensity (FI) values of non-veno-occlusive regions (FI_Non ), veno-occlusive regions (FI_VO ) and ischaemic regions (FI_IS ) were calculated using luminance analysing software.

RESULTS

Of the 21 patients, ten, four and seven underwent limited resection, monosegmentectomy/sectionectomy and hemihepatectomy respectively, with excision of major hepatic veins. Median veno-occlusive liver volume was 80 (range 30-458) ml. Fluorescence imaging visualized veno-occlusive regions as territories with lower FI compared with non-veno-occlusive regions, and ischaemic regions as territories with no fluorescence after intravenous ICG injection. Median FI_IS /FI_Non was lower than median FI_VO /FI_Non (0·22 versus 0·59; P = 0·002). There were no deaths in hospital or within 30 days, and only one major complication.

CONCLUSION

ICG fluorescence imaging with hepatic vein clamping visualized non-veno-occlusive, veno-occlusive and ischaemic regions. This technique may guide liver transection by intraoperative navigation, enhancing the safety and accuracy of liver resection.

Safety and efficacy of cryopreserved homologous veins for venous reconstruction in pancreatoduodenectomy

BACKGROUND

There are several techniques for reconstructing the portal vein-superior mesenteric vein during pancreatoduodenectomy. The aim of the present study was to present our results with portal vein-superior mesenteric vein reconstruction using cryopreserved homologous veins during pancreatoduodenectomy for patients with pancreatic head cancer.

METHODS

Patients who underwent pancreatoduodenectomy for pancreatic head cancer were reviewed retrospectively. In patients with portal vein-superior mesenteric vein resection, the detailed method of reconstruction and clinical outcomes were reviewed. Clinical characteristics, patient survival, and portal vein-superior mesenteric vein patency were compared between those with and without homologous vein grafts. Factors affecting the patency of reconstructed veins were assessed by univariate analysis.

RESULTS

Among 144 patients undergoing pancreatoduodenectomy, portal vein-superior mesenteric vein resection was performed in 36 patients (25%); 18 (50%) underwent reconstruction with homologous veins, and the other 18 (50%) underwent reconstruction without homologous veins. The extent of portal vein-superior mesenteric vein involvement, operative time, duration of clamping of portal vein-superior mesenteric vein, intraoperative blood loss, and length of the venous resection were greater (P ≤ .013 each) in those with homologous vein grafts. There was no significant difference in postoperative morbidity/mortality, patient survival, or portal vein-superior mesenteric vein patency. The 1- and 2-year overall patency of portal vein-superior mesenteric vein was 76% and 71%, respectively, while the 2-year patencies were 67% and 67% in those with homologous veins and 87% and 73% in those without homologous veins without difference between the groups. Circumferential resection and pathologic portal vein-superior mesenteric vein involvement were associated with the patency of the reconstructed vein (P = .002 and P = .028, resp).

CONCLUSION

Use of homologous venous grafts for portal vein-superior mesenteric vein reconstruction are feasible alternatives during pancreatoduodenectomy for advanced pancreatic head cancer.

A 15-year experience of two hundred and twenty five consecutive right hepatectomies

BACKGROUND

In case of liver tumor, surgical resection is the therapeutic gold standard to increase patient survival. Among liver resections, right hepatectomy (RH) is defined as a major hepatectomy. The first aim of this study was to analyze the overall morbidity and mortality of patients undergoing RH, the second aim was to assess changes in both patients characteristic and surgical parameters and mortality rates in a single center institution.

MATERIALS

From 2001 to December 2015, 225 RH were performed in our center. We analyzed two time period: 2001-2007 and 2008-2015.

RESULTS

Ninety days post operative mortality was observed in 9 cases (4%) for the overall cohort. We observed a difference between the two groups in the use of Pringle Maneuver (p<0,001). This result is consistent in each major surgical indication: HCC (p=0,001), CLM (p=0,015) and BT (p=0,015). The estimated blood losses improved (p=0,028), particularly for the HCC cases (p=0,024). No difference was observed in terms of number of transfusions received between the two groups. Reduced length of stay was observed in the second group (p<0,001), more markedly for CLM cases (p=0,001).

CONCLUSION

To further improve the outcomes of RH, it is important to performed this major hepatectomy in hepatobiliary centers with an overall liver resection experience of at least few hundred cases.

Venous drainage map of the liver for complex hepatobiliary surgery and liver transplantation

BACKGROUND

Inflow and outflow patency of the liver parenchyma is required to maximize the metabolic function of the liver. However, the definition and distribution of hepatic venous drainage regions has yet to be reported. The aim of this study was to define major hepatic venous tributaries and investigate the mean drainage volume of each territory.

METHODS

Three-dimensional (3D) simulations from the livers of 100 healthy donors were reviewed for living donor liver transplantation to determine the distribution of the significant hepatic venous tributaries and the drainage patterns of each segment.

RESULTS

The left hepatic vein (LHV), middle hepatic vein (MHV), and right hepatic vein (RHV) contributed a mean drainage of 20.7%, 32.7%, and 39.6% of the entire liver, respectively. Accessory hepatic veins accounted for remaining 7.0%. The middle right hepatic vein (MRHV) and inferior right hepatic vein (IRHV) accounted for a mean total drainage of 8.0% and 10.6%, respectively, when they present. In addition, major tributaries of hepatic veins were clearly detected, and their typical distributions were described.

CONCLUSIONS

Knowledge of hepatic venous territories is necessary for complex hepatobiliary surgery. This "venous drainage map" may provide useful information for complex liver surgery and transplantation.

Surgical Indications and Procedures for Resection of Hepatic Malignancies Confined to Segment VII

OBJECTIVE

To establish a strategy for surgical resection of hepatic malignancies confined to segment VII.

BACKGROUND

Various surgical procedures can be used to resect hepatic malignancies in segment VII, the deepest region of the liver, by open and/or laparoscopic approaches: nonanatomic wedge resection (WR), segmentectomy VII, right lateral sectionectomy (RLS), and right hepatectomy.

METHODS

WR and segmentectomy VII were applied as first-line surgical procedures for colorectal liver metastasis (CRLM) and hepatocellular carcinoma (HCC), respectively. RLS and right hepatectomy were indicated only when tumor infiltration to the proximal Glissonian sheath was suspected. Operative outcomes were evaluated in 200 consecutive patients who underwent hepatic resection for HCC (n = 120) or CRLM (n = 80).

RESULTS

WR, segmentectomy VII, RLS, and right hepatectomy were performed in 104 (52.0%), 57 (28.5%), 22 (11.0%), and 17 (8.5%) patients, respectively. Local hepatectomy (WR and segmentectomy VII) led to shorter operation times and lower blood loss volumes than did extensive hepatectomy (RLS and right hepatectomy). Thoracotomy was performed in half of the WR and two-thirds of the segmentectomy VII procedures. The availability of a laparoscopic approach was 40% (8 patients) after its application in October 2012.

CONCLUSIONS

Even for hepatic malignancies located in segment VII, WR and segmentectomy should be prioritized over extensive hepatectomy to preserve the postoperative functional hepatic volume. Full mobilization of the right liver and a good surgical field provided by a large thoracoabdominal or abdominal incision or a laparoscopic approach are key factors for safe performance of deep hepatic transection.

Complete removal of the tumor-bearing portal territory decreases local tumor recurrence and improves disease-specific survival of patients with hepatocellular carcinoma

BACKGROUND & AIMS

Anatomic resection (AR) of the tumor-bearing portal territory has been reported to be associated with a decreased recurrence of hepatocellular carcinoma (HCC). However, because of the heterogeneity of the study populations, its oncologic advantage remains controversial. The objective of the present study was to determine the clinical advantage of AR for primary HCC, based on the data from a large prospective cohort treated under a constant surgical policy.

METHODS

In 209 Child-Pugh class A patients with primary, solitary HCC measuring ⩽5.0cm in diameter, which was resectable either by AR or limited resection (non-AR), the overall survival (OS) and disease-free survival (DFS) were compared with patients in whom complete AR was achieved and those who eventually ended up with non-AR after adjustment for the propensity scores to select AR. Advantages of AR in disease-specific survival and local recurrence were also evaluated by competing-risks regression to clarify the true oncologic impact of AR.

RESULTS

The AR group showed better DFS than the non-AR group (HR, 0.67; 95% CI, 0.45-0.99; p=0.046), while no significant difference was observed in OS (hazard ratio [HR], 0.82; 95% CI, 0.46-1.48; p=0.511). Competing-risks regression revealed that AR significantly decreases local recurrence (HR, 0.12; 95% CI, 0.05-0.30; p<0.001) and improves disease-specific survival (HR, 0.50; 95% CI, 0.28-0.90; p=0.020), while the other cause of death was highly influenced by patient age (>65years) (HR, 7.51; 95% CI, 2.16-26.04; p=0.002) and not associated with AR.

CONCLUSION

Complete removal of tumor-bearing portal territory decreases the risk of local recurrence and death from HCC.

Evaluating the current surgical strategies for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death worldwide. Despite careful surveillance programs and the development of antiviral therapy for hepatitis virus infection, the occurrence rate of HCC remains high. Liver resection and liver transplantation are mainstay curative treatments. Most patients with HCC have impaired liver function, and surgical treatment is always accompanied by the risk of decompensation of the remnant liver, especially when the volume of the remnant liver is too small and the liver function too low to meet metabolic demands. The mortality of liver resection has dramatically decreased over the last three decades from 20% to less than 5% due to the accumulation of knowledge of liver anatomy, perioperative management and preoperative assessment of liver function. Here we provide an overview of the multidisciplinary treatments and current standard treatment strategies for HCC, to explore the possibility of expanding surgical treatments beyond the current standards.

Advances in Assessment and Planning for Surgical Treatment of Hepatocellular Carcinoma

This chapter covers recent important topics relevant to ensuring safe liver resection. In particular, preoperative and intraoperative techniques, such as 3-dimensional CT, intraoperative ultrasonography with contrast agent and fluorescence imaging using indocyanine green are reportedly useful and have been applied to liver resection and liver transplantation. We, herein, describe the performance of liver resection under the guidance of these techniques and present tips for more accurate intraoperative tumor detection and safer surgical procedures.

Reappraisal of the inferior right hepatic vein preserving liver resection

BACKGROUND

To resect tumors infiltrating to the right hepatic vein at its root, right hemihepatectomy or that following portal vein embolization (PVE) is applied. If the IRHV is sizable, the IRHV preserving liver resection can be another option.

METHODS

Between 1994 and 2007, the IRHV preserving liver resection was performed in 21 patients (IRHV group). The short-term outcomes after surgery of them p.

RESULTS

There were no mortality and no significant difference between the IRHV and RH groups concerning the blood loss, the morbidity rates and the duration of hospital stay. The median operation time was shorter in the IRHV group than in the RH group (393 vs. 480 min, p = 0.0409). The median weight of resected specimen of the IRHV group was 293 g (range: 20-982), which was significantly lighter than that of the RH group (median: 680 g [250-4,300], p < 0.001). The median percentage of resected volume to standard liver volume was significantly smaller in the IRHV group than in the RH group (25.8 vs. 52.2%, p < 0.001).

CONCLUSION

The IRHV preserving liver resection remains a safe and useful procedure.

Role of surgery in colorectal cancer liver metastases

Colorectal carcinoma (CRC) is the third most common cancer, and approximately 35%-55% of patients with CRC will develop hepatic metastases during the course of their disease. Surgical resection represents the only chance of long-term survival. The goal of surgery should be to resect all metastases with negative histological margins while preserving sufficient functional hepatic parenchyma. Although resection remains the only chance of long-term survival, management strategies should be tailored for each case. For patients with extensive metastatic disease who would otherwise be unresectable, the combination of advances in medical therapy, such as systemic chemotherapy (CTX), and the improvement in surgical techniques for metastatic disease, have enhanced prognosis with prolongation of the median survival rate and cure. The use of portal vein embolization and preoperative CTX may also increase the number of patients suitable for surgical treatment. Despite current treatment options, many patients still experience a recurrence after hepatic resection. More active systemic CTX agents are being used increasingly as adjuvant therapy either before or after surgery. Local tumor ablative therapies, such as microwave coagulation therapy and radiofrequency ablation therapy, should be considered as an adjunct to hepatic resection, in which resection cannot deal with all of the tumor lesions. Formulation of an individualized plan, which combines surgery with systemic CTX, is a necessary task of the multidisciplinary team. The aim of this paper is to discuss different approaches for patients that are treated due to CRC liver metastasis.

Three-dimensional volumetry in 107 normal livers reveals clinically relevant inter-segment variation in size

BACKGROUND

The anatomic resection of Couinaud's segments is one of the key techniques in liver surgery. However, the territories and volumes of the eight segments are not adequately assessed based on portal branching.

METHODS

Three-dimensional (3D) perfusion-based volumetry was performed in 107 normal livers. Based on Couinaud classification, the portal branches were identified and the volumes of each segment were calculated. The relationships between branching patterns of the portal veins and segmental volumes were assessed.

RESULTS

In descending order of volume, median volumes of segments VIII, VII, IV, V, III, VI, II and I were recorded. Segment VIII was the largest, accounting for a median of 26.1% (range: 11.1-38.0%) of total liver volume (TLV), whereas segments II and III each represented <10% of TLV. In 69.2% of subjects, the portal branches of segment V diverged from the trunk of the branches of segment VIII. No relationship was found between branching type and segment volume.

CONCLUSIONS

The territories and volumes of Couinaud's segments vary among segments, as well as among individuals. Detailed 3D volumetry is useful for preoperative evaluations of the dissection line and of future liver remnant volume in anatomic segmentectomy.