Perioperative impact of liver venous deprivation compared with portal venous embolization in patients undergoing right hepatectomy: preliminary results from the pioneer center

Synchronous portal vein embolization of terminal branches with transcatheter arterial chemoembolization before planned major hepatectomy for hepatitis B virus-related hepatocellular carcinoma: a single-center retrospective cohort study

BACKGROUND

Terminal branches portal vein embolization (TBPVE) is a novel technical modification. The clinical effect of synchronous TBPVE with transcatheter arterial chemoembolization (TACE) before planned major hepatectomy in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) remains unknown.

METHODS

From November 2016 to December 2021, the study enrolled 115 patients with HBV-related HCC who were scheduled for major hepatectomy but had insufficient future liver remnant (FLR). Patients were grouped according to whether they received TBPVE combined with TACE (the TBPVE group [n = 62]) or PVE combined with TACE (the PVE group [n = 53]). This study compared the outcomes of the procedures and the perioperative and long-term outcomes of patients who subsequently underwent major hepatectomy between the 2 groups.

RESULTS

FLR volume increment and degree of hypertrophy were significantly higher in the TBPVE group than in the PVE group (P ≤.003). FLR proliferation was pronounced remarkably within the first 2 weeks after TBPVE synchronous with TACE, and the kinetic growth rates were 17.4 mL/d (IQR, 12.7-21.9) in the first week and 6.9 mL/d (IQR, 4.1-11.1) in the second week. Of note, 54 patients in the TBPVE group and 41 patients in the PVE group finally underwent major hepatectomies. The Pringle maneuver time, intraoperative blood loss, transfusion, and postoperative hospital stays were lower in the TBPVE group than in the PVE group (P <.05). Disease-free survival (DFS) rates were better in the TBPVE group than in the PVE group (P =.042).

CONCLUSION

TBPVE synchronous with TACE induced safe and rapid FLR hypertrophy with satisfactory efficacy in patients with initially unresectable HBV-related HCC, improved the planned major hepatectomy resectability rate, and had better DFS.

Beta-catenin/sirtuin 1/farnesoid X receptor pathway promotion of portal vein ligation and parenchymal transection-induced rapid liver regeneration

BACKGROUND

By accelerating the regeneration of the future liver remnant, portal vein ligation and parenchymal transection allows for more extensive hepatectomy. Given that the mechanism remains poorly understood, the aim of this study was to investigate the mechanism of portal vein ligation and parenchymal transection-induced liver regeneration.

METHODS

A portal vein ligation and parenchymal transection-induced liver regeneration mouse model was established, followed by RNA microarray analysis to identify candidate molecules. Genomic deletion and chemical manipulation of target molecules were used to explore their functions in portal vein ligation and parenchymal transection-induced liver regeneration. Validation was conducted using a diseased liver model and human samples.

RESULTS

Portal vein ligation and parenchymal transection-induced liver regeneration was significantly accelerated compared with that in sham-operated mice (P < .05). An RNA microarray revealed that Sirtuin 1 is a crucial molecule in the proliferation of the future liver remnant. Regardless of whether Sirtuin 1 is inhibited chemically or through genetic deletion, portal vein ligation and parenchymal transection-induced liver regeneration is distinctly attenuated. Further investigation revealed that Sirtuin 1 promoted portal vein ligation and parenchymal transection-induced liver regeneration via the farnesoid X receptor. In addition, beta-catenin also was found to participate in the process of future liver remnant proliferation. Chemical inhibition of beta-catenin markedly impaired but activation of WNT/beta-catenin mildly enhanced portal vein ligation and parenchymal transection-induced liver regeneration (P < .05). Deletion of Sirtuin 1 blocked the facilitating effect of beta-catenin on portal vein ligation and parenchymal transection-induced liver regeneration. These findings were validated in diseased liver models and patient samples, confirming the correlation between the beta-catenin/Sirtuin 1/farnesoid X receptor pathway and portal vein ligation and parenchymal transection-induced liver regeneration.

CONCLUSION

Activation of the beta-catenin/Sirtuin 1/farnesoid X receptor pathway offers critical mechanistic insights into accelerating portal vein ligation and parenchymal transection-induced liver regeneration. Modulation of beta-catenin/Sirtuin 1/farnesoid X receptor may therefore improve clinical outcomes in patients receiving staged hepatectomy.

Propensity Score-Matched Analysis of Liver Venous Deprivation and Portal Vein Embolization Before Planned Hepatectomy in Patients with Extensive Colorectal Liver Metastases and High-Risk Factors for Inadequate Regeneration

BACKGROUND

Liver venous deprivation (LVD) is known to induce better future liver remnant (FLR) hypertrophy than portal vein embolization (PVE). The role of LVD, compared with PVE, in inducing FLR hypertrophy and allowing safe hepatectomy for patients with extensive colorectal liver metastases (CLM) and high-risk factors for inadequate hypertrophy remains unclear.

METHODS

Patients undergoing LVD (n = 22) were matched to patients undergoing PVE (n = 279) in a 1:3 ratio based on propensity scores, prior to planned hepatectomy for CLM at a single center (1998-2023). The propensity scores accounted for high-risk factors for inadequate hypertrophy, namely pre-procedure standardized FLR (sFLR), body mass index, number of systemic therapy cycles, an extension of PVE to segment IV portal vein branches, prior resection, and chemotherapy-associated liver injury.

RESULTS

The matched cohort included 78 patients (LVD, n = 22; PVE, n = 56). Baseline characteristics were comparable. The number of tumors in the whole liver was similar but more LVD patients had five or more tumors in the left liver (32% vs. 11%; p = 0.024). Post-procedure sFLR was similar but LVD patients had a significantly higher degree of hypertrophy (16% vs. 11%; p = 0.017) and kinetic growth rate (3.9 vs. 2.4% per week; p = 0.006). More LVD patients underwent extended right hepatectomy (93% vs. 55%; p = 0.008). Only one patient had postoperative hepatic insufficiency after PVE, and no patients died within 90 days of hepatectomy.

CONCLUSION

In patients with extensive CLM and high-risk factors, LVD is associated with better FLR hypertrophy compared with PVE and allows for safely performing curative-intent extended major hepatectomy.

Factors influencing failure of progression to completion hepatectomy following liver venous deprivation procedures (PVE or DVE): a longitudinal observational study

BACKGROUND

Two-staged hepatectomy (TSH) with portal (PVE) or dual vein embolization (DVE) gained acceptance in liver surgery. The current study assesses the incidence and causes of failure to progress to completion hepatectomy following PVE/DVE and its influence on overall survival (OS).

METHODS

This is a longitudinal observational study of patients who underwent PVE or DVE between April 2010-December 2023. Future liver remnant (FLR) volume was measured at least four weeks later. Restaging and resectability was assessed on imaging performed within 6-8 weeks of planned completion surgery.

RESULTS

130 patients underwent PVE (90) or DVE (40) during the study period. Of these, 73 (56 %) patients proceeded to definitive resection. Reasons for failure to progress to completion surgery were: disease progression (79 %), declined fitness for surgery (3.5 %) and inadequate FLR volume (14 %). Synchronous disease is a poor prognostic factor for achieving completion hepatectomy CRLM patients (p = 0.009). The median OS with and without completion hepatectomy was 38 months vs. 13 months in CRLM patients (p=<.001) and 31 months vs. 26 months in pCCA groups respectively (p = 0.471).

CONCLUSION

A significant percentage of patients did not progress to completion hepatectomy due to disease progression. Patient selection and efficient pathways are essential to improve resection rates following these resource-intensive procedures.

Liver Vein Deprivation versus Portal Vein Embolization: Retrospective Review of Safety and Effectiveness

PURPOSE

To compare the safety and effectiveness of liver vein deprivation (LVD) and portal vein embolization (PVE) in patients scheduled to undergo liver resection.

MATERIALS AND METHODS

This retrospective cohort study included 59 patients who underwent either PVE (n = 28) or LVD (n = 31) in preparation for liver resection. The primary outcome was percent change in future liver remnant volume (FLRV). The secondary endpoints were degree of hypertrophy (DH) and kinetic growth rate (KGR).

RESULTS

Low baseline FLRV and time interval in days between the procedure and follow-up imaging (Ti) positively impacted the primary and secondary endpoints in both groups. Percent change in FLRV was higher in the LVD group (52.8% ± 5.3) than in the PVE group (22.3% ± 3.0, P < .001). DH was also higher in the LVD group (15.4% ± 1.7) than in the PVE group (6.4% ± 0.9, P < .001). KGR did not differ significantly between groups (LVD, 0.54%/d ± 0.06; PVE, 0.35%/d ± 0.1; P = .239). When patients with a baseline standardized FLRV of >35% were excluded from the analysis, the LVD group demonstrated higher values than the PVE group in KGR (0.57%/d ± 0.06 vs 0.29%/d ± 0.05, P < .001), percent change in FLRV (64.2% ± 6.0 vs 25.9% ± 4.3, P < .001), and DH (15.4% ± 1.4 vs 6.6% ± 1.0, P < .001). No adverse events were noted in either group.

CONCLUSIONS

LVD appears to be safe and may be superior to PVE in inducing hypertrophy of future liver remnant in patients scheduled to undergo surgical resection.

The assessment of impaired liver function and prognosis in hepatocellular carcinoma

INTRODUCTION

The impairment of liver function strongly limits the therapeutic options for hepatocellular carcinoma (HCC), and the assessment of liver function is key to finding the appropriate therapy for patients suffering from this disease. Furthermore, preexisting liver dysfunction has a negative impact on the prognosis of patients in addition to the malignant potential of HCC. Hence, defining the optimal treatment of patients with HCC requires a comprehensive examination with liver function being a crucial part of it.

AREAS COVERED

This review will provide an overview of the currently existing methods for evaluating the liver function in patients with HCC. Assessment of liver function includes scoring systems but also functional and technical methods. In addition, the role of these tests in different treatment facilities such as liver resection, transplantation, interventional and systemic therapy is summarized.

EXPERT OPINION

A comprehensive pretherapeutic assessment of the liver function includes laboratory-based scoring systems, as well as imaging- and non-imaging-based functional tests. Combining diverse parameters can help to improve the safety and efficacy of HCC therapy particularly in patients with compromised liver function. Future research should focus on optimizing pretherapeutic assessment recommendations for each therapy.

Liver venous deprivation (LVD) before extended hepatectomy: a French multicentric retrospective cohort

Background

Post-hepatectomy liver failure (PHLF) is the first cause of death after major hepatectomy, and future liver remnant (FLR) volume is the main factor predicting PHLF. Liver venous deprivation (LVD) via portal and hepatic vein embolization has been suggested to induce a better hypertrophy of the FLR than portal vein embolization. The aim of this retrospective multicentric study was to assess safety, feasibility and efficacity of LVD in a French national multicentric register.

Methods

Between 2016 and 2023, LVD was performed in 7 expert centers, for patients with liver malignancies requiring major hepatectomy with an FLR percentage of total liver volume (FLR%) ≤25% for a healthy liver or <30% for a diseased liver. FLR volumetry was assessed before and 4 weeks after the procedure.

Results

One hundred and ninety-two patients were included in the study. The technical success rate was 100% and severe complication rate post-LVD was 2.6% (5/192). The FLR% increased by 61.7% over an average of 27±9.7 days. Major hepatectomy was performed 40 days after LVD on 161 (83.8%) patients. Hepatectomy was not performed on 31 (16.2%) patients, mostly because of oncological progression. Severe postoperative complications (Clavien-Dindo grade ≥ IIIA) occurred in 21.1% (34/161) of patients. Postoperative mortality rate was 4.3% (7/161).

Conclusions

This study is the largest to confirm that LVD is a safe, reproducible, efficient technique that induces rapid major FLR growth. However, this new technique needs to be standardized and harmonized between centers to ensure uniform results.

Comprehensive Review of Future Liver Remnant (FLR) Assessment and Hypertrophy Techniques Before Major Hepatectomy: How to Assess and Manage the FLR

BACKGROUND

The regenerative capacities of the liver and improvements in surgical techniques have expanded the possibilities of resectability. Liver resection is often the only curative treatment for primary and secondary malignancies, despite the risk of post-hepatectomy liver failure (PHLF). This serious complication (with a 50% mortality rate) can be avoided by better assessment of liver volume and function of the future liver remnant (FLR).

OBJECTIVE

The aim of this review was to understand and assess clinical, biological, and imaging predictors of PHLF risk, as well as the various hypertrophy techniques, to achieve an adequate FLR before hepatectomy.

METHOD

We reviewed the state of the art in liver regeneration and FLR hypertrophy techniques.

RESULTS

The use of new biological scores (such as the aspartate aminotransferase/platelet ratio index + albumin-bilirubin [APRI+ALBI] score), concurrent utilization of 99mTc-mebrofenin scintigraphy (HBS), or dynamic hepatocyte contrast-enhanced MRI (DHCE-MRI) for liver volumetry helps predict the risk of PHLF. Besides portal vein embolization, there are other FLR optimization techniques that have their indications in case of risk of failure (e.g., associating liver partition and portal vein ligation for staged hepatectomy, liver venous deprivation) or in specific situations (transarterial radioembolization).

CONCLUSION

There is a need to standardize volumetry and function measurement techniques, as well as FLR hypertrophy techniques, to limit the risk of PHLF.

Comparison of liver venous deprivation with portal vein embolization alone in patients undergoing major liver resection: a systematic review and meta-analysis

BACKGROUND

The clinical efficacy and safety between liver venous deprivation (LVD) and portal vein embolization (PVE) prior to major hepatectomy is still unclear.

METHODS

Studies comparing LVD and PVE were obtained by systemically searching PubMed, Embase, and Cochrane Library Central databases through 22 December 2023.

RESULTS

Ten studies including 588 patients were reviewed. Compared with PVE group, LVD group exhibited an increased liver resection rate (OR, 1.89; 95% CI, 1.13-3.15; P = 0.01), a faster KGR (MD, 1.37; 95% CI, 0.31-2.42; P = 0.01), and a shorter time to hepatectomy (MD, -6.66; 95% CI, -8.03 to -5.30; P < 0.0001). The pooled results showed that post-embolization complications (OR, 1.35; 95% CI, 0.66-2.74), overall postoperative complications (OR, 1.09; 95% CI, 0.68-1.75), severe complications (Clavien-Dindo ≥ III) (OR, 0.70; 95% CI, 0.43-1.14), and 90-day mortality (OR, 0.38; 95% CI, 0.13-1.09) were not significantly different in both groups. LVD group had significantly lower post-hepatectomy liver failure (PHLF) than PVE group (OR, 0.45; 95% CI, 0.22-0.91; P = 0.03).

CONCLUSION

LVD outperforms PVE regarding liver resection rate and future liver remnant (FLR) hypertrophy and shows comparable safety to PVE. In addition, LVD allowed for major hepatectomy with lower incidence of PHLF.

Image-guided percutaneous strategies to improve the resectability of HCC: Portal vein embolization, liver venous deprivation, or radiation lobectomy?

Despite considerable advances in surgical technique, many patients with hepatic malignancies are not operative candidates due to projected inadequate hepatic function following resection. Consequently, the size of the future liver remnant (FLR) is an essential consideration when predicting a patient's likelihood of liver insufficiency following hepatectomy. Since its initial description 30 years ago, portal vein embolization has become the standard of care for augmenting the size and function of the FLR preoperatively. However, new minimally invasive techniques have been developed to improve surgical candidacy, chief among them liver venous deprivation and radiation lobectomy. The purpose of this review is to discuss the status of preoperative liver augmentation prior to resection of hepatocellular carcinoma with a focus on these three techniques, highlighting the distinctions between them and suggesting directions for future investigation.

Liver volumetry and liver-regenerative interventions: history, rationale, and emerging tools

BACKGROUND

Postoperative hepatic insufficiency (PHI) is the most feared complication after hepatectomy. Volume of the future liver remnant (FLR) is one objectively measurable indicator to identify patients at risk of PHI. In this review, we summarized the development and rationale for the use of liver volumetry and liver-regenerative interventions and highlighted emerging tools that could yield new advancements in liver volumetry.

METHODS

A review of MEDLINE/PubMed, Embase, and Cochrane Library databases was conducted to identify literature related to liver volumetry. The references of relevant articles were reviewed to identify additional publications.

RESULTS

Liver volumetry based on radiologic imaging was developed in the 1980s to identify patients at risk of PHI and later used in the 1990s to evaluate grafts for living donor living transplantation. The field evolved in the 2000s by the introduction of standardized FLR based on the hepatic metabolic demands and in the 2010s by the introduction of the degree of hypertrophy and kinetic growth rate as measures of the FLR regenerative and functional capacity. Several liver-regenerative interventions, most notably portal vein embolization, are used to increase resectability and reduce the risk of PHI. In parallel with the increase in automation and machine assistance to physicians, many semi- and fully automated tools are being developed to facilitate liver volumetry.

CONCLUSION

Liver volumetry is the most reliable tool to detect patients at risk of PHI. Advances in imaging analysis technologies, newly developed functional measures, and liver-regenerative interventions have been improving our ability to perform safe hepatectomy.

Efficacy and perioperative safety of different future liver remnant modulation techniques: a systematic review and network meta-analysis

BACKGROUND

In daily clinical practice, different future liver remnant (FLR) modulation techniques are increasingly used to allow a liver resection in patients with insufficient FLR volume. This systematic review and network meta-analysis aims to compare the efficacy and perioperative safety of portal vein ligation (PVL), portal vein embolization (PVE), liver venous deprivation (LVD) and associating liver partition and portal vein ligation for staged hepatectomy (ALPPS).

METHODS

A literature search for studies comparing liver resections following different FLR modulation techniques was performed in MEDLINE, Embase and Cochrane Central, and pairwise and network meta-analyses were conducted.

RESULTS

Overall, 23 studies comprising 1557 patients were included. LVD achieved the greatest increase in FLR (17.32 %, 95% CI 2.49-32.15), while ALPPS was most effective in preventing dropout before the completion hepatectomy (OR 0.29, 95% CI 0.15-0.55). PVL tended to be associated with a longer time to completion hepatectomy (MD 5.78 days, 95% CI -0.67-12.23). Liver failure occurred less frequently after LVD, compared to PVE (OR 0.35, 95% CI 0.14-0.87) and ALPPS (OR 0.28, 95% CI 0.09-0.85).

DISCUSSION

ALPPS and LVD seem superior to PVE and PVL in terms of achieved FLR increase and subsequent treatment completion. LVD was associated with lower rates of post hepatectomy liver failure, compared to both PVE and ALPPS. A summary of the protocol has been prospectively registered in the PROSPERO database (CRD42022321474).

Role of the portal system in liver regeneration: From molecular mechanisms to clinical management

The liver has a strong regenerative capacity that ensures patient recovery after hepatectomy and liver transplantation. The portal system plays a crucial role in the dual blood supply to the liver, making it a significant factor in hepatic function. Several surgical strategies, such as portal vein ligation, associating liver partition and portal vein ligation for staged hepatectomy, and dual vein embolization, have highlighted the portal system's importance in liver regeneration. Following hepatectomy or liver transplantation, the hemodynamic properties of the portal system change dramatically, triggering regeneration via shear stress and the induction of hypoxia. However, excessive portal hyperperfusion can harm the liver and negatively affect patient outcomes. Furthermore, as the importance of the gut-liver axis has gradually been revealed, the effect of metabolites and cytokines from gut microbes carried by portal blood on liver regeneration has been acknowledged. From these perspectives, this review outlines the molecular mechanisms of the portal system's role in liver regeneration and summarizes therapeutic strategies based on the portal system intervention to promote liver regeneration.

A systematic review and meta-analysis of liver venous deprivation versus portal vein embolization before hepatectomy: future liver volume, postoperative outcomes, and oncological safety

Introduction

This systematic review aimed to compare liver venous deprivation (LVD) with portal vein embolization (PVE) in terms of future liver volume, postoperative outcomes, and oncological safety before major hepatectomy.

Methods

We conducted this systematic review and meta-analysis following the PRISMA guidelines 2020 and AMSTAR 2 guidelines. Comparative articles published before November 2022 were retained.

Results

The literature search identified nine eligible comparative studies. They included 557 patients, 207 in the LVD group and 350 in the PVE group. This systematic review and meta-analysis concluded that LVD was associated with higher future liver remnant (FLR) volume after embolization, percentage of FLR hypertrophy, lower failure of resection due to low FLR, faster kinetic growth, higher day 5 prothrombin time, and higher 3 years' disease-free survival. This study did not find any difference between the LVD and PVE groups in terms of complications related to embolization, FLR percentage of hypertrophy after embolization, failure of resection, 3-month mortality, overall morbidity, major complications, operative time, blood loss, bile leak, ascites, post hepatectomy liver failure, day 5 bilirubin level, hospital stay, and three years' overall survival.

Conclusion

LVD is as feasible and safe as PVE with encouraging results making some selected patients more suitable for surgery, even with a small FLR.

Systematic review registration

The review protocol was registered in PROSPERO before conducting the study (CRD42021287628).

Post-hepatectomy liver failure: A timeline centered review

BACKGROUND

Post-hepatectomy liver failure (PHLF) is a leading cause of postoperative mortality after liver surgery. Due to its significant impact, it is imperative to understand the risk stratification and preventative strategies for PHLF. The main objective of this review is to highlight the role of these strategies in a timeline centered way around curative resection.

DATA SOURCES

This review includes studies on both humans and animals, where they addressed PHLF. A literature search was conducted across the Cochrane Library, Embase, MEDLINE/PubMed, and Web of Knowledge electronic databases for English language studies published between July 1997 and June 2020. Studies presented in other languages were equally considered. The quality of included publications was assessed using Downs and Black's checklist. The results were presented in qualitative summaries owing to the lack of studies qualifying for quantitative analysis.

RESULTS

This systematic review with 245 studies, provides insight into the current prediction, prevention, diagnosis, and management options for PHLF. This review highlighted that liver volume manipulation is the most frequently studied preventive measure against PHLF in clinical practice, with modest improvement in the treatment strategies over the past decade.

CONCLUSIONS

Remnant liver volume manipulation is the most consistent preventive measure against PHLF.

Essential updates 2021/2022: Update in surgical strategy for perihilar cholangiocarcinoma

Resection is the only potential curative treatment for perihilar cholangiocarcinoma (PHC); however, complete resection is often technically challenging due to the anatomical location. Various innovative approaches and procedures were invented to circumvent this limitation but the rates of postoperative morbidity (20%-78%) and mortality (2%-15%) are still high. In patients diagnosed with resectable PHC, deliberate and coordinated preoperative workup and optimization of the patient and future liver remnant are crucial. Biliary drainage is recommended to relieve obstructive jaundice and optimize the clinical condition before liver resection. Biliary drainage for PHC can be performed either by endoscopic biliary drainage or percutaneous transhepatic biliary drainage. To date there is no consensus about which method is preferred. The volumetric assessment of the future remnant liver volume and optimization mainly using portal vein embolization is the gold standard in the management of the risk to develop post hepatectomy liver failure. The improvement of systemic chemotherapy has contributed to prolong the survival not only in patients with unresectable PHC but also in patients undergoing curative surgery. In this article, we review the literature and discuss the current surgical treatment of PHC.

A bibliometric and visualized analysis of preoperative future liver remnant augmentation techniques from 1997 to 2022

Background

The size and function of the future liver remnant (FLR) is an essential consideration for both eligibility for treatment and postoperative prognosis when planning surgical hepatectomy. Over time, a variety of preoperative FLR augmentation techniques have been investigated, from the earliest portal vein embolization (PVE) to the more recent Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) and liver venous deprivation (LVD) procedures. Despite numerous publications on this topic, no bibliometric analysis has yet been conducted.

Methods

Web of Science Core Collection (WoSCC) database was searched to identify studies related to preoperative FLR augmentation techniques published from 1997 to 2022. The analysis was performed using the CiteSpace [version 6.1.R6 (64-bit)] and VOSviewer [version 1.6.19].

Results

A total of 973 academic studies were published by 4431 authors from 920 institutions in 51 countries/regions. The University of Zurich was the most published institution while Japan was the most productive country. Eduardo de Santibanes had the most published articles, and Masato Nagino was the most frequently co-cited author. The most frequently published journal was HPB, and the most cited journal was Ann Surg, with 8088 citations. The main aspects of preoperative FLR augmentation technique is to enhance surgical technology, expand clinical indications, prevent and treat postoperative complications, ensure long-term survival, and evaluate the growth rate of FLR. Recently, hot keywords in this field include ALPPS, LVD, and Hepatobiliary Scintigraphy.

Conclusion

This bibliometric analysis provides a comprehensive overview of preoperative FLR augmentation techniques, offering valuable insights and ideas for scholars in this field.

A Sticky Situation: Glue Migration during Hepatic Vein Embolization

The addition of hepatic venous embolization to portal venous embolization to achieve ipsilateral liver venous deprivation before major hepatectomy has been suggested to increase the extent of hypertrophy of the future liver remnant. The presented case discusses a hepatic vein embolization procedure complicated by the unintended migration of a glue cast used to achieve hepatic venous occlusion and subsequent management with endovascular retrieval of the glue cast from the inferior vena cava. The emerging role of hepatic venous embolization and associated complications are also discussed.

Liver Venous Deprivation Versus Portal Vein Embolization Before Major Hepatectomy for Colorectal Liver Metastases: A Retrospective Comparison of Short- and Medium-Term Outcomes

BACKGROUND

Liver venous deprivation (LVD) is a recent radiological technique performed to induce hypertrophy of the future liver remnant. Medium-term results of major hepatectomy after LVD have never been compared with the actual standard of care, portal vein embolization (PVE).

METHODS

We retrospectively compared data from 33 consecutive patients who had undergone LVD (n = 17) or PVE (n = 16) prior to a right hemi-hepatectomy or right extended hepatectomy indicated for colorectal liver metastases (CRLM) between May 2015 and December 2019.

RESULTS

The 1-year and 3-year overall survival (OS) rates in the LVD group were 81.3% (95% confidence interval [CI]: 72-90) and 54.7% (95% CI: 46-63), respectively, against 85% (95% CI: 69-101) and 77.4% (95% CI: 54-100) in the PVE group; the differences were not statistically significant (p = 0.64). The median disease-free survival (DFS) rate was also comparable: 6 months (95% CI: 4-7) in the LVD group and 12 months (95% CI: 1.5-13) in the PVE group (p = 0.29). The overall intra-operative and post-operative complication rates were similar between the two groups. The mean daily kinetic growth rate (KGR) was found to be higher after LVD than after PVE (0.2% vs. 0.1%, p = 0.05; 10 cc/day vs. 4.8 cc/day, p = 0.03), as was the mean increase in future liver remnant volume (FLR-V) (49% vs. 27%, p = 0.01).

CONCLUSIONS

The LVD technique is well tolerated in patients undergoing right hemi-hepatectomy or right extended hepatectomy for CRLM. When compared with the PVE technique, the LVD technique has similar peri-operative and medium-term outcomes, but higher KGR and FLR-V increase.

Efficacy and safety of different options for liver regeneration of future liver remnant in patients with liver malignancies: a systematic review and network meta-analysis

BACKGROUND

Several treatments induce liver hypertrophy for patients with liver malignancies but insufficient future liver remnant (FLR). Herein, the aim of this study is to compare the efficacy and safety of existing surgical techniques using network meta-analysis (NMA).

METHODS

We searched PubMed, Web of Science, and Cochrane Library from databases for abstracts and full-text articles published from database inception through Feb 2022. The primary outcome was the efficacy of different procedures, including standardized FLR (sFLR) increase, time to hepatectomy, resection rate, and R0 resection margin. The secondary outcome was the safety of different treatments, including the rate of Clavien-Dindo≥3a and 90-day mortality.

RESULTS

Twenty-seven studies, including three randomized controlled trials (RCTs), three prospective trials (PTs), and twenty-one retrospective trials (RTs), and a total number of 2075 patients were recruited in this study. NMA demonstrated that the Associating Liver Partition and Portal vein ligation for Staged hepatectomy (ALPPS) had much higher sFLR increase when compared to portal vein embolization (PVE) (55.25%, 95% CI 45.27-65.24%), or liver venous deprivation(LVD) (43.26%, 95% CI 22.05-64.47%), or two-stage hepatectomy (TSH) (30.53%, 95% CI 16.84-44.21%), or portal vein ligation (PVL) (58.42%, 95% CI 37.62-79.23%). ALPPS showed significantly shorter time to hepatectomy when compared to PVE (-32.79d, 95% CI -42.92-22.66), or LVD (-34.02d, 95% CI -47.85-20.20), or TSH (-22.85d, 95% CI -30.97-14.72), or PVL (-43.37d, 95% CI -64.11-22.62); ALPPS was considered as the highest resection rate when compared to TSH (OR=6.09; 95% CI 2.76-13.41), or PVL (OR =3.52; 95% CI 1.16-10.72), or PVE (OR =4.12; 95% CI 2.19-7.77). ALPPS had comparable resection rate with LVD (OR =2.20; 95% CI 0.83-5.86). There was no significant difference between them when considering the R0 marge rate. ALPPS had a higher Clavien-Dindo≥3a complication rate and 90-day mortality compared to other treatments, although there were no significant differences between different procedures.

CONCLUSIONS

ALPPS demonstrated a higher regeneration rate, shorter time to hepatectomy, and higher resection rate than PVL, PVE, or TSH. There was no significant difference between them when considering the R0 marge rate. However, ALPPS developed the trend of higher Clavien-Dindo≥3a complication rate and 90-day mortality compared to other treatments.

Current evidence on posthepatectomy liver failure: comprehensive review

INTRODUCTION

Despite important advances in many areas of hepatobiliary surgical practice during the past decades, posthepatectomy liver failure (PHLF) still represents an important clinical challenge for the hepatobiliary surgeon. The aim of this review is to present the current body of evidence regarding different aspects of PHLF.

METHODS

A literature review was conducted to identify relevant articles for each topic of PHLF covered in this review. The literature search was performed using Medical Subject Heading terms on PubMed for articles on PHLF in English until May 2022.

RESULTS

Uniform reporting on PHLF is lacking due to the use of various definitions in the literature. There is no consensus on optimal preoperative assessment before major hepatectomy to avoid PHLF, although many try to estimate future liver remnant function. Once PHLF occurs, there is still no effective treatment, except liver transplantation, where the reported experience is limited.

DISCUSSION

Strict adherence to one definition is advised when reporting data on PHLF. The use of the International Study Group of Liver Surgery criteria of PHLF is recommended. There is still no widespread established method for future liver remnant function assessment. Liver transplantation is currently the only effective way to treat severe, intractable PHLF, but for many indications, this treatment is not available in most countries.

Portal vein embolization versus dual vein embolization for management of the future liver remnant in patients undergoing major hepatectomy: meta-analysis

BACKGROUND

This meta-analysis aimed to compare progression to surgery, extent of liver hypertrophy, and postoperative outcomes in patients planned for major hepatectomy following either portal vein embolization (PVE) or dual vein embolization (DVE) for management of an inadequate future liver remnant (FLR).

METHODS

An electronic search was performed of MEDLINE, Embase, and PubMed databases using both medical subject headings (MeSH) and truncated word searches. Articles comparing PVE with DVE up to January 2022 were included. Articles comparing sequential DVE were excluded. ORs, risk ratios, and mean difference (MD) were calculated using fixed and random-effects models for meta-analysis.

RESULTS

Eight retrospective studies including 523 patients were included in the study. Baseline characteristics between the groups, specifically, age, sex, BMI, indication for resection, and baseline FLR (ml and per cent) were comparable. The percentage increase in hypertrophy was larger in the DVE group, 66 per cent in the DVE group versus 27 per cent in the PVE group, MD 39.07 (9.09, 69.05) (P = 0.010). Significantly fewer patients failed to progress to surgery in the DVE group than the PVE group, 13 per cent versus 25 per cent respectively OR 0.53 (0.31, 0.90) (P = 0.020). Rates of post-hepatectomy liver failure 13 per cent versus 22 per cent (P = 0.130) and major complications 20 per cent versus 28 per cent (Clavien-Dindo more than IIIa) (P = 0.280) were lower. Perioperative mortality was lower with DVE, 1 per cent versus 10 per cent (P = 0.010).

CONCLUSION

DVE seems to produce a greater degree of hypertrophy of the FLR than PVE alone which translates into more patients progressing to surgery. Higher quality studies are needed to confirm these results.

Resectability of bilobar liver tumours after simultaneous portal and hepatic vein embolization versus portal vein embolization alone: meta-analysis

BACKGROUND

Many patients with bi-lobar liver tumours are not eligible for liver resection due to an insufficient future liver remnant (FLR). To reduce the risk of posthepatectomy liver failure and the primary cause of death, regenerative procedures intent to increase the FLR before surgery. The aim of this systematic review is to provide an overview of the available literature and outcomes on the effectiveness of simultaneous portal and hepatic vein embolization (PVE/HVE) versus portal vein embolization (PVE) alone.

METHODS

A systematic literature search was conducted in PubMed, Web of Science, and Embase up to September 2022. The primary outcome was resectability and the secondary outcome was the FLR volume increase.

RESULTS

Eight studies comparing PVE/HVE with PVE and six retrospective PVE/HVE case series were included. Pooled resectability within the comparative studies was 75 per cent in the PVE group (n = 252) versus 87 per cent in the PVE/HVE group (n = 166, OR 1.92 (95% c.i., 1.13-3.25)) favouring PVE/HVE (P = 0.015). After PVE, FLR hypertrophy between 12 per cent and 48 per cent (after a median of 21-30 days) was observed, whereas growth between 36 per cent and 67 per cent was reported after PVE/HVE (after a median of 17-31 days). In the comparative studies, 90-day primary cause of death was similar between groups (2.5 per cent after PVE versus 2.2 per cent after PVE/HVE), but a higher 90-day primary cause of death was reported in single-arm PVE/HVE cohort studies (6.9 per cent, 12 of 175 patients).

CONCLUSION

Based on moderate/weak evidence, PVE/HVE seems to increase resectability of bi-lobar liver tumours with a comparable safety profile. Additionally, PVE/HVE resulted in faster and more pronounced hypertrophy compared with PVE alone.

Parenchyma-Sparing Liver Resection or Regenerative Liver Surgery: Which Way to Go?

Liver resection for malignant tumors should respect oncological margins while ensuring safety and improving the quality of life, therefore tumor staging, underlying liver disease and performance status should all be attentively assessed in the decision process. The concept of parenchyma-sparing liver surgery is nowadays used as an alternative to major hepatectomies to address deeply located lesions with intricate topography by means of complex multiplanar parenchyma-sparing liver resections, preferably under the guidance of intraoperative ultrasound. Regenerative liver surgery evolved as a liver growth induction method to increase resectability by stimulating the hypertrophy of the parenchyma intended to remain after resection (referred to as future liver remnant), achievable by portal vein embolization and liver venous deprivation as interventional approaches, and portal vein ligation and associating liver partition and portal vein ligation for staged hepatectomy as surgical techniques. Interestingly, although both strategies have the same conceptual origin, they eventually became caught in the never-ending parenchyma-sparing liver surgery vs. regenerative liver surgery debate. However, these strategies are both valid and must both be mastered and used to increase resectability. In our opinion, we consider parenchyma-sparing liver surgery along with techniques of complex liver resection and intraoperative ultrasound guidance the preferred strategy to treat liver tumors. In addition, liver volume-manipulating regenerative surgery should be employed when resectability needs to be extended beyond the possibilities of parenchyma-sparing liver surgery.

Promoting Surgical Resection through Future Liver Remnant Hypertrophy

An inadequate future liver remnant (FLR) can preclude curative-intent surgical resection for patients with primary or secondary hepatic malignancies. For patients with normal baseline liver function and without risk factors, an FLR of 20% is needed to maintain postsurgical hepatic function. However, the FLR requirement is higher for patients who are exposed to systemic chemotherapy (FLR, >30%) or have cirrhosis (FLR, >40%). Interventional radiologic and surgical methods to achieve FLR hypertrophy are evolving, including portal vein ligation, portal vein embolization, radiation lobectomy, hepatic venous deprivation, and associating liver partition and portal vein ligation for staged hepatectomy. Each technique offers particular advantages and disadvantages. Knowledge of these procedures can help clinicians to choose the suitable technique for each patient. The authors review the techniques used to develop FLR hypertrophy, focusing on technical considerations, outcomes, and the advantages and disadvantages of each approach. Online supplemental material is available for this article. ^©RSNA, 2022.

Simultaneous portal and hepatic vein embolization is better than portal embolization or ALPPS for hypertrophy of future liver remnant before major hepatectomy: A systematic review and network meta-analysis

BACKGROUND

Post-hepatectomy liver failure (PHLF) is the Achilles' heel of hepatic resection for colorectal liver metastases. The most commonly used procedure to generate hypertrophy of the functional liver remnant (FLR) is portal vein embolization (PVE), which does not always lead to successful hypertrophy. Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) has been proposed to overcome the limitations of PVE. Liver venous deprivation (LVD), a technique that includes simultaneous portal and hepatic vein embolization, has also been proposed as an alternative to ALPPS. The present study aimed to conduct a systematic review as the first network meta-analysis to compare the efficacy, effectiveness, and safety of the three regenerative techniques.

DATA SOURCES

A systematic search for literature was conducted using the electronic databases Embase, PubMed (MEDLINE), Google Scholar and Cochrane.

RESULTS

The time to operation was significantly shorter in the ALPPS cohort than in the PVE and LVD cohorts by 27 and 22 days, respectively. Intraoperative parameters of blood loss and the Pringle maneuver demonstrated non-significant differences between the PVE and LVD cohorts. There was evidence of a significantly higher FLR hypertrophy rate in the ALPPS cohort when compared to the PVE cohort, but non-significant differences were observed when compared to the LVD cohort. Notably, the LVD cohort demonstrated a significantly better FLR/body weight (BW) ratio compared to both the ALPPS and PVE cohorts. Both the PVE and LVD cohorts demonstrated significantly lower major morbidity rates compared to the ALPPS cohort. The LVD cohort also demonstrated a significantly lower 90-day mortality rate compared to both the PVE and ALPPS cohorts.

CONCLUSIONS

LVD in adequately selected patients may induce adequate and profound FLR hypertrophy before major hepatectomy. Present evidence demonstrated significantly lower major morbidity and mortality rates in the LVD cohort than in the ALPPS and PVE cohorts.

Current trends in regenerative liver surgery: Novel clinical strategies and experimental approaches

Liver resections are performed to cure patients with hepatobiliary malignancies and metastases to the liver. However, only a small proportion of patients is resectable, largely because only up to 70% of liver tissue is expendable in a resection. If larger resections are performed, there is a risk of post-hepatectomy liver failure. Regenerative liver surgery addresses this limitation by increasing the future liver remnant to an appropriate size before resection. Since the 1980s, this surgery has evolved from portal vein embolization (PVE) to a multiplicity of methods. This review presents an overview of the available methods and their advantages and disadvantages. The first use of PVE was in patients with large hepatocellular carcinomas. The increase in liver volume induced by PVE equals that of portal vein ligation, but both result only in a moderate volume increase. While awaiting sufficient liver growth, 20%–40% of patients fail to achieve resection, mostly due to the progression of disease. The MD Anderson Cancer Centre group improved the PVE methodology by adding segment 4 embolization (“high-quality PVE”) and demonstrated that oncological results were better than non-surgical approaches in this previously unresectable patient population. In 2012, a novel method of liver regeneration was proposed and called Associating Liver Partition and Portal vein ligation for Staged hepatectomy (ALPPS). ALPPS accelerated liver regeneration by a factor of 2–3 and increased the resection rate to 95%–100%. However, ALPPS fell short of expectations due to a high mortality rate and a limited utility only in highly selected patients. Accelerated liver regeneration, however, was there to stay. This is evident in the multiplicity of ALPPS modifications like radiofrequency or partial ALPPS. Overall, rapid liver regeneration allowed an expansion of resectability with increased perioperative risk. But, a standardized low-risk approach to rapid hypertrophy has been missing and the techniques used and in use depend on local expertise and preference. Recently, however, simultaneous portal and hepatic vein embolization (PVE/HVE) appears to offer both rapid hypertrophy and no increased clinical risk. While prospective randomized comparisons are underway, PVE/HVE has the potential to become the future gold standard.

Future remnant liver optimization: preoperative assessment, volume augmentation procedures and management of PVE failure

Surgery is the cornerstone treatment for patients with primary or metastatic hepatic tumors. Thanks to surgical and anesthetic technological advances, current indications for liver resections have been significantly expanded to include any patient in whom all disease can be resected with a negative margin (R0) while preserving an adequate future residual liver (FRL). Posthepatectomy liver failure (PHLF) is still a feared complication following major liver surgery, associated with high morbidity, mortality and cost implications. PHLF is mainly linked to both the size and quality of the FRL. Significant advances have been made in detailed preoperative assessment to predict and mitigate this complication, even if an ideal methodology has yet to be defined. Several procedures have been described to induce hypertrophy of the FRL when needed. Each technique has its advantages and limitations, and among them portal vein embolization (PVE) is still considered the standard of care. About 20% of patients after PVE fail to undergo the scheduled hepatectomy, and newer secondary procedures, such as segment 4 embolization, ALPPS and HVE, have been proposed as salvage strategies. The aim of this review was to discuss the current modalities available and new perspectives in the optimization of FRL in patients undergoing major liver resection.

Liver venous deprivation versus associating liver partition and portal vein ligation for staged hepatectomy for colo-rectal liver metastases: a comparison of early and late kinetic growth rates, and perioperative and oncological outcomes

BACKGROUND

Different techniques have been developed to optimize the Future Liver Remnant (FLR). Associated liver partition and portal vein ligation for staged hepatectomy (ALPPS) and liver venous deprivation (LVD) have shown the higher hypertrophy rates, but their place in clinical practice is still debated.

METHODS

Thirty-two consecutive ALPPS and LVD procedures for CRLM performed between December 2015 and December 2019 were included. This retrospective study evaluated kinetic growth rates (KGR) as primary outcome, and perioperative and oncological outcomes as secondary endpoints.

RESULTS

A total of 17 patients underwent LVD before surgery, whereas 15 underwent ALPPS. On early evaluation (7 vs 9 days, respectively), KGR did not differ between ALPPS and LVD cohort (0.8% per day vs 0.3% per day, p = 0.70; 23 cc/day vs 26 cc/day, p = 0.31). Late evaluation (21 vs 9 days) showed a KGR significantly decreased in the LVD group (0.6% per day vs 0.2% per day, p = 0.21; 20 cc/day vs 10 cc/day p = 0.02). Mean FLR-V increase was comparable in the two groups (60% vs 49%, p 0.32). Successful resection rate was 100% and 94% in LVD and ALPPS group, respectively. The hospital stay (p < 0.0001) and severe complications rate (p = 0.05) were lower after LVD. One and 3-years overall survival (OS) were 72,7% and 27,4% in the ALPSS group, versus 81,3% and 54,7% in LVD group (p = 0.10). The Median DFS was comparable between both techniques (6.1 months and 5.9 respectively, p = 0.66).

CONCLUSIONS

LVD and ALPPS shows similar KGR during the early period following preparation as well as similar survival outcomes. Hospital stay and severe complications are lower after LVD.

Percutaneous liver venous deprivation: outcomes in heavily pretreated metastatic colorectal cancer patients

BACKGROUND

To evaluate liver venous deprivation (LVD) outcomes in patients with colorectal liver metastasis (CRLM) heavily pretreated with systemic and hepatic arterial infusion pump (HAIP) chemotherapies that had an anticipated insufficient future liver remnant (FLR) hypertrophy after portal vein embolization (PVE).

METHODS

PVE was performed with liquid embolics using a transsplenic or ipsilateral transhepatic approach. Simultaneously and via a trans-jugular approach, the right hepatic vein was embolized with vascular plugs. Liver volumetry was assessed on computed tomography before and 3-6 weeks after LVD.

RESULTS

Twelve consecutive CRLM patients that underwent LVD before right hepatectomy or trisectionectomy were included, all previously treated with systemic chemotherapy for a mean of 11.9 months. Six patients had additional HAIP. After embolization, FLR ratio increased from 28.7% ± 5.9 to 42.2% ± 9.0 (P < 0.01). Mean kinetic growth rate (KGR) was 3.56%/week ± 2.3, with a degree of hypertrophy (DH) of 13.8% ± 7.1. In the HAIP subgroup, mean KGR and DH were respectively 3.58%/week ± 2.8 and 14.3% ± 8.7. No severe complications occurred. Ten patients reached surgery after 39 days ± 7.5.

CONCLUSION

In heavily pretreated patients, LVD safely stimulated a rapid and effective FLR hypertrophy, with a resultant high rate of resection.

Shifting concepts in the management of colorectal liver metastases

Management of patients with colorectal liver metastases has evolved considerably due to a better understanding of the biology of the disease with concurrent improvements in surgical techniques, oncological strategies and radiological interventions. This review article examines the factors that have contributed to this radical change. Management will be discussed in relation to chemotherapy, surgery and interventional radiology. The addition of chemotherapy and biological agents has greatly extended the reach and scope of surgery. Parenchymal sparing resections, repeat resections, two stage hepatectomy and Associating Liver Partition and Portal Vein ligation are all available to the hepatobiliary surgeon who deals with colorectal liver metastases. Interventional radiology techniques like liver venous deprivation may also replace established surgical practice. Whilst traditionally it was thought that only a few liver metastases could be treated effectively, nowadays tumour number is no longer a limiting factor provided enough functioning liver can be spared and the patient can tolerate the operation.

Induction of Robust Future Liver Remnant Hypertrophy Before Hepatectomy With a Modified Liver Venous Deprivation Technique Using a Trans-venous Access for Hepatic Vein Embolization

Purpose: Hepatic and/or portal vein embolization are performed before hepatectomy for patients with insufficient future liver remnant and usually achieved with a trans-hepatic approach. The aim of the present study is to describe a modified trans-venous liver venous deprivation technique (mLVD), avoiding the potential risks and limitations of a percutaneous approach to hepatic vein embolization, and to assess the safety, efficacy, and surgical outcome after mLVD. Materials and Methods: Retrospective single-center institutional review board-approved study. From March 2016 to June 2019, consecutive oncologic patients with combined portal and hepatic vein embolization were included. CT volumetric analysis was performed before and after mLVD to assess liver hypertrophy. Complications related to mLVD and surgical outcome were obtained from medical records. Results: Thirty patients (62.7 ± 14.5 years old, 20 men) with liver metastasis (60%) or primary liver cancer (40%) underwent mLVD. Twenty-one patients (70%) had hepatic vein anatomic variants. Technical success of mLVD was 100%. Four patients had complications (three minor and one major). FLR hypertrophy was 64.2% ± 51.3% (mean ± SD). Twenty-four patients (80%) underwent the planned hepatectomy and no surgery was canceled as a consequence of mLVD complications or insufficient hypertrophy. Fifty percent of patients (12/24) had no or mild complications after surgery (Clavien-Dindo 0-II), and 45.8% (11/24) had more serious complications (Clavien-Dindo III-IV). Thirty-day mortality was 4.2% (1/24). Conclusion: mLVD is an effective method to induce FLR hypertrophy. This technique is applicable in a wide range of oncologic situations and in patients with complex right liver vein anatomy.

Portal vein embolization: rationale, techniques, outcomes and novel strategies

The incidence of liver cancer has grown in the past decade, with 905,677 new cases and 830,180 deaths in 2020. According to the highest annual fatality ratio, liver cancer is the third-leading cause of cancer-related deaths worldwide. Surgical resection is the mainstay treatment for long-term survival. However, only 25% of patients are surgical candidates. Recent surgical concepts, techniques and multidisciplinary management were developed, including interventional radiology procedures that improve the management algorithm, expand the indications and limit dropouts from curative treatment. This review summarizes up-to-date information on interventional radiology in the management of liver tumors.

State-of-the-art surgery for hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is the most commonly diagnosed primary liver tumor with an increasing incidence worldwide. Management of patients with HCC is largely dictated by the presence of cirrhosis, disease stage, underlying liver function, and patient performance status.

PURPOSE

We provide an update on key aspects of surgical treatment options for patients with HCC. RESULTS & CONCLUSIONS: Liver resection and transplantation remain cornerstone treatment options for patients with early-stage disease and constitute the only potentially curative options for HCC. Selection of patients for surgical treatment should include a thorough evaluation of tumor characteristics and biology, as well as evidence-based use of various available treatment options to achieve optimal long-term outcomes for patients with HCC.

Muscularity Defined by the Combination of Muscle Quantity and Quality is Closely Related to Both Liver Hypertrophy and Postoperative Outcomes Following Portal Vein Embolization in Cancer Patients

BACKGROUND

Portal vein embolization (PVE) is a common procedure for preventing hepatic insufficiency after major hepatectomy. While evaluating the body composition of surgical patients is common, the impact of muscularity defined by both muscle quantity and quality on liver hypertrophy after PVE and associated outcomes after major hepatectomy in patients with hepatobiliary cancer remain unclear.

METHODS

This retrospective review included 126 patients who had undergone hepatobiliary cancer resection after PVE. Muscularity was measured on preoperative computed tomography images by combining the skeletal mass index and intramuscular adipose content. Various factors including the degree of hypertrophy (DH) of the future liver remnant and post-hepatectomy outcomes were compared according to muscularity.

RESULTS

DH did not differ by malignancy type. Patients with high muscularity had better DH after PVE (P = 0.028), and low muscularity was an independent predictor for poor liver hypertrophy after PVE [odds ratio (OR), 3.418; 95% confidence interval (CI), 1.129-10.352; P = 0.030]. In subgroup analyses in which patients were stratified into groups based on primary hepatobiliary tumors and metastases, low muscularity was associated with higher incidence of post-hepatectomy liver failure (PHLF) ≥ grade B (P = 0.018) and was identified as an independent predictor for high-grade PHLF (OR 3.931; 95% CI 1.113-13.885; P = 0.034) among the primary tumor group. In contrast, muscularity did not affect surgical outcomes in patients with metastases.

CONCLUSIONS

Low muscularity leads to poor liver hypertrophy after PVE and is also a predictor of PHLF, particularly in primary hepatobiliary cancer.

The evolution of surgery for colorectal liver metastases: A persistent challenge to improve survival

Only a few decades ago, the opinion that colorectal liver metastases were a palliative diagnosis changed. In fact, previously, the prevailing view was strongly resistant against resecting colorectal liver metastases. Constant technical improvement of liver surgery and, much later, effective chemotherapy allowed for a successful wider application of surgery. The clinical use of portal vein embolization was the starting signal of regenerative liver surgery, where insufficient liver volume can be expanded to an extent where safe resection is possible. Today, a number of these techniques including portal vein ligation, associating liver partition and portal vein ligation for staged hepatectomy, and bi-embolization (portal and hepatic vein) can be successfully used to address an insufficient future liver remnant in staged resections. It turned out that the road to success is embedding surgery in a well-orchestrated oncological concept of controlling systemic disease. This concept was the prerequisite that meant liver transplantation could enter the treatment strategy for colorectal liver metastases, ending up with a 5-year overall survival of 80% in highly selected cases. In particular, techniques combining principles of 2-stage hepatectomy and liver transplantation, such as "resection and partial liver segment 2-3 transplantation with delayed total hepatectomy" (RAPID) are on the rise. These techniques enable the use of partial liver grafts with primarily insufficient liver volume. All this progress also prompted a number of innovative local therapies to address recurrences ultimately transferring colorectal liver metastases from instantly deadly into a chronic disease in some cases.

Optimization of the future remnant liver: review of the current strategies in Europe

Liver resection still represent the treatment of choice for liver malignancies, but in some cases inadequate future remnant liver (FRL) can lead to post hepatectomy liver failure (PHLF) that still represents the most common cause of death after hepatectomy. Several strategies in recent era have been developed in order to generate a compensatory hypertrophy of the FRL, reducing the risk of post hepatectomy liver failure. Portal vein embolization, portal vein ligation, and ALLPS are the most popular techniques historically adopted up to now. The liver venous deprivation and the radio-embolization are the most recent promising techniques. Despite even more precise tools to calculate the relationship among volume and function, such as scintigraphy with ^99mTc-mebrofenin (HBS), no consensus is still available to define which of the above mentioned augmentation strategy is more adequate in terms of kind of surgery, complexity of the pathology and quality of liver parenchyma. The aim of this article is to analyse these different strategies to achieve sufficient FRL.

Ligation of the middle hepatic vein to increase hypertrophy induction during the ALPPS procedure

PURPOSE

Here, we analyse the technical modification of the ALPPS procedure, ligating the middle hepatic vein during the first step of the operation to enhance remnant liver hypertrophy.

METHODS

In 20 of 37 ALPPS procedures, the middle hepatic vein was ligated during the first step. Hypertrophy of the functional remnant liver volume was assessed in addition to postoperative courses.

RESULTS

Volumetric analysis showed a significant volume increase, especially for patients with colorectal metastases. Pre-existing liver parenchyma damage (odds ratio = 0.717, p = 0.017) and preoperative chemotherapy were found to be significant predictors (odds ratio = 0.803, p = 0.045) of higher morbidity and mortality. In addition, a survival benefit for maintenance of middle hepatic vein was shown.

CONCLUSION

This technical modification of the ALPPS procedure can accentuate future liver remnant volume hypertrophy. The higher morbidity and mortality observed are most likely associated with pre-existing parenchymal damage within this group.

99mTc-mebrofenin hepatobiliary scintigraphy and volume metrics before liver preparation: correlations and discrepancies in non-cirrhotic patients

Background

Accurate identification of insufficient future liver remnant (FLR) is required to select patients for liver preparation and limit the risk of post-hepatectomy liver failure (PHLF). The objective of this study was to investigate the correlations and discrepancies between the most-commonly used FLR volume metrics and ^99mTc-mebrofenin hepatobiliary scintigraphy (HBS).

Methods

In 101 non-cirrhotic patients who underwent HBS before major hepatectomy, we retrospectively analyzed the correlations and discrepancies between FLR function and FLR volume metrics: actual percentage (FLRV%), standardized to body surface area (FLRV%^BSA) and weight (FLRV%^weight), and FLR to body weight ratio (FLRV-BWR).

Results

Among 67 patients with FLR function ≥2.69%/min/m², PHLF was observed in none and 13 patients according to respectively 50-50 and ISGLS criteria. FLRV%, FLRV%^BSA, FLRV%^weight and FLRV-BWR significantly correlated with FLR function (P<0.001), with Spearman's correlation coefficients of 0.680, 0.704, 0.698, and 0.711, respectively. No difference was observed between the areas under the curve of FLRV%, FLRV%^BSA, FLRV%^weight and FLR-BWR (all P=ns). Overall, the percentages of patients misclassified by FLRV%, FLRV%^BSA, FLRV%^weight (thresholds: 30%) and FLR-BWR (threshold: 0.5) versus FLR function (threshold: 2.69%/min/m²) were 23.8% (95% CI: 15.9-33.3%), 18.8% (95% CI: 11.7-27.8%), 17.8% (95% CI: 11-26.7%), and 31.7% (95% CI: 22.8-41.7%), respectively. FLR volume metrics wrongly classified 1-13.9% of patients with sufficient FLR function (i.e., ≥2.69%/min/m²), and 9.9-30.7% of patients with insufficient FLR function. FLRV-BWR was the most and the least reliable measure to identify patients with sufficient and insufficient FLR function, respectively.

Conclusions

Despite significant correlations, the discrepancy rates between FLR volume and function metrics speaks in favor of implementing ^99mTc-mebrofenin HBS in the work-up before liver preparation.

Complex Liver Resections for Intrahepatic Cholangiocarcinoma

The only curative treatment option for intrahepatic cholangiocarcinoma (iCCA) is liver resection. Due to central tumor localization and vascular invasion, complex liver resections play an important role in curative treatment. However, the long-term outcomes after complex liver resection are not known. Methods: A retrospective cohort study was conducted for all patients undergoing liver surgery for iCCA. Complex liver resections included ante situm resections, associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) and major liver resection with vascular reconstructions. Results: Forty-nine patients (34%) received complex liver resection, 66 patients (46%) received conventional liver resection and 28 patients (20%) were not resectable during exploration. Preoperative characteristics were not different between the groups, except for Union for International Cancer Control (UICC) stages. The postoperative course for complex liver resections was associated with more complications and perioperative mortality. However, long-term survival was not different between complex and conventional resections. Independent risk factors for survival were R0 resections and UICC stage. Four patients underwent ante situm resection without any mortality. Conclusions: Complex liver resections are justified in selected patients and survival is comparable with conventional liver resections. Survival in iCCA is affected by UICC stage or resections margins and not by the complexity of the case.