Assessment of future remnant liver function using hepatobiliary scintigraphy in patients undergoing major liver resection

Regional quantification of metabolic liver function using hyperpolarized [1-13C] pyruvate MRI

Assessment of liver function is essential before partial hepatectomy to predict the risk of post hepatectomy liver failure, a severe and life-threatening complication. Traditional methods have focused on expected future liver remnant (FLR) volume estimation. However, liver volume does not always correlate with function. We suggest that metabolism might be a better surrogate for function than volume. Therefore, we aimed to investigate the metabolic changes in a porcine model of partial portal vein ligation (PVL) using hyperpolarized magnetic resonance imaging (HP-MRI). Specifically, we sought to quantify and compare the pyruvate metabolism in the FLR and the deportalized liver (DL).Six pigs underwent PVL. HP-MRI with [1-13C] pyruvate was performed at baseline, post-surgery, and 1 week after surgery. Metabolic conversion was quantified with kinetic modelling of the rate constants of pyruvate to lactate (kPL) and pyruvate to alanine (kPA). Mean kPL was increased in FLR compared to DL at post-surgery and 1 week after surgery (P = 0.002), while kPA was unaltered (P = 0.761). These findings indicate a metabolic shift towards glycolysis in the FLR. This non-invasive metabolic imaging technique could serve as a powerful tool for evaluation of regional liver function prior to partial hepatectomy and consequently improve patient outcomes.

EASL Clinical Practice Guidelines on the management of hepatocellular carcinoma

Liver cancer is the third leading cause of cancer-related deaths worldwide, with hepatocellular carcinoma (HCC) accounting for approximately 90% of primary liver cancers. Advances in diagnostic and therapeutic tools, along with improved understanding of their application, are transforming patient treatment. Integrating these innovations into clinical practice presents challenges and necessitates guidance. These clinical practice guidelines offer updated advice for managing patients with HCC and provide a comprehensive review of pertinent data. Key updates from the 2018 EASL guidelines include personalised surveillance based on individual risk assessment and the use of new tools, standardisation of liver imaging procedures and diagnostic criteria, use of minimally invasive surgery in complex cases together with updates on the integrated role of liver transplantation, transitions between surgical, locoregional, and systemic therapies, the role of radiation therapies, and the use of combination immunotherapies at various stages of disease. Above all, there is an absolute need for a multiparametric assessment of individual risks and benefits, considering the patient's perspective, by a multidisciplinary team encompassing various specialties.

Hepatic Resection for Hepatocellular Carcinoma

Hepatic resection has long been considered the preferred treatment for hepatocellular carcinoma (HCC) when feasible, but its role, as well as the outcomes is evolving rapidly. This article explores the impact of the changing demographics of HCC, reviews current criteria for resection, considers the roles of liver transplantation and nonsurgical locoregional therapies vis-a-vis resection, highlights the potential of new systemic therapies (particularly immune checkpoint inhibitors) to improve outcomes, details the common complications associated with resection, and discusses recurrence of HCC after resection and its management.

Hepatobiliary scintigraphy and liver function changes in patients with hepatocellular carcinoma treated with 166Ho-radioembolization : HBS in HCC treated with holmium-166

BACKGROUND

To study the feasibility of hepatobiliary scintigraphy (HBS) to improve selection and planning of patients with hepatocellular carcinoma (HCC) treated with holmium-166 (166Ho)-microspheres radioembolization.

RESULTS

Thirty-one patients with HCC were included and treated with 166Ho- radioembolization as part of a prospective phase 2 study. Twenty-seven patients were eligible for analysis, 67% had a cirrhotic liver morphology on imaging, 70% had multifocal disease and 51% had bilobar disease. None of the patients had clinical signs of liver decompensation (Child Pugh ≤ B7, median MELD 9 or ALBI - 2.55). Global and regional hepatic function was based on manual delineation of HBS using 200 MBq 99mTc-mebrofenine, acquired during screening and approximately three months after 166Ho-radioembolization, referred to as liver clearance rate (LCR). In line with LCR at baseline, a significant correlation was found between LCR and lab results, including bilirubin, albumin, ALT, MELD-score, and ALBI-score (p < 0.05) during follow-up. HBS showed a significant decrease in median LCR (-16%; p = 0.0017) and volume (-17%; p = 0.0027) in the treated liver, without a significant increase in the non-treated liver. Median relative change in overall LCR in non-cirrhotics was 0% (range - 23-33%), in cirrhotics - 10% (range - 40 - 19%; p = 0.40).

CONCLUSION

HBS showed that hepatic function and volume significantly decreased in parts of the liver treated with 166Ho-microspheres radioembolization in patients with HCC. Cirrhotic patients do not seem to have the capacity to increase hepatic function in the treated part of the liver.

TRIAL REGISTRATION

Registry name: Clinicaltrials.gov.

TRIAL NUMBER

NCT03379844. Date of registration: 21 November 2017. Trial URL: https://clinicaltrials.gov/study/NCT03379844?cond=hcc&term=hepar primary&rank=1#study-overview .

Liver Resection for Hepatocellular Carcinoma: Recent Advances

Hepatocellular carcinoma (HCC) represents a significant global health burden. Surgery remains a cornerstone in the curative treatment of HCC, and recent years have witnessed notable advancements aimed at refining surgical techniques and improving patient outcomes. This review presents a detailed examination of the recent innovations in HCC surgery, highlighting key developments in both surgical approaches and adjunctive therapies. Advanced imaging technologies have revolutionized preoperative assessment, enabling precise tumour localization and delineation of vascular anatomy. The use of three-dimensional rendering has significantly augmented surgical planning, facilitating more accurate and margin-free resections. The advent of laparoscopic and robotic-assisted surgical techniques has ushered in an era of minimal access surgery, offering patients the benefits of shorter hospital stays and faster recovery times, while enabling equivalent oncological outcomes. Intraoperative innovations such as intraoperative ultrasound (IOUS) and fluorescence-guided surgery have emerged as valuable adjuncts, allowing real-time assessment of tumour extent and aiding in parenchyma preservation. The integration of multimodal therapies, including neoadjuvant and adjuvant strategies, has allowed for 'bio-selection' and shown the potential to optimize patient outcomes. With the advent of augmented reality and artificial intelligence (AI), the future holds immense potential and may represent significant strides towards optimizing patient outcomes and refining the standard of care.

Dynamic [99mTc]Tc-mebrofenin SPECT/CT in preoperative planning of liver resection: a prospective study

BACKGROUND

At least 20% of the future liver remnant must function properly after liver tumor resection to avoid post-hepatectomy liver failure (PHLF). [99mTc]Tc-mebrofenin scintigraphy and SPECT are unique noninvasive, quantitative methods for evaluating liver function via hepatocellular bilirubin clearance.

AIM

To evaluate the value of dynamic [99mTc]Tc-mebrofenin SPECT/CT parameters for predicting clinically relevant PHLF according to the ISGLS criteria.

METHODS

Thirty-five patients underwent dynamic [99mTc]Tc-mebrofenin SPECT/CT imaging to determine the FLR volumetric rate, functional volume rate, total liver filtration and FLR filtration. On the same day, two-dimensional ultrasound shear wave elastography (2D-SWE) was used to assess parenchymal fibrosis in the FLR. The quantitative dynamic SPECT parameters were compared with the relevant clinical scores and ICG.

RESULTS

The total liver filtration was inversely correlated with the ICG-R15 and MELD-Na score. Twenty-four patients underwent major liver resection due to an adequate FLR rate and did not die within 90 days after the procedure. ROC analysis revealed that the FLR filtration was a significant predictor of PHLF. The best cutoff value for FLR filtration was 2.72%/min/m2.

CONCLUSION

Dynamic [99mTc]Tc-mebrofenin SPECT/CT is an essential tool for selecting patients at risk of clinically relevant PHLF after liver 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.

Initial experience with Double-vein Embolization in Hungary

Introduction

In recent years several new techniques have emerged to induce hypertrophy of the future liver remnant prior to major hepatectomies. We aimed to summarize our initial experience with Double-vein Embolization as the first center in Hungary.

Methods

Between March 2023 and August 2024 a total of 16 Double-vein Embolization procedures were performed in Semmelweis University. Future liver remnant volume was calculated based on computed tomography scans obtained within 4 weeks prior and 2-3 weeks after the procedure. Tc-99m mebrofenin hepatobiliary scintigraphy results were available for 12/16 patients.

Results

Technical success rate was 100 %. No major complication was observed. Successful resection rate was 93.8 %. One patient died due to post-hepatectomy liver failure. Future liver remnant volume and ratio increased significantly after the procedure compared to baseline (433.1 ± 163.8 cm3 vs. 603.5 ± 201.8 cm3, p < 0.0001 and 27.2 ± 6.5 % vs. 37 ± 8.8 %, p < 0.0001, respectively). Future liver remnant clearance improved significantly 1 and 2 weeks after the procedure (1.68 ± 0.58 %/min/m2 vs. 2.44 ± 0.64 %/min/m2 and 2.39 ± 0.31 %/min/m2, respectively). Mean function gain was 50.6 % after one week and 60.1% after two weeks, respectively.

Discussion

Volumetric and functional outcomes in the present study are comparable with results reported in the literature. Our findings provide further evidence that Double-vein Embolization is a safe procedure that offers sufficient volumetric and functional gain in most candidates for liver resection. However, further studies are needed to define the exact place of this new technique in clinical practice.

Central Liver Segments Resections vs Extended Hepatectomies in Children: Single-Center Experience

BACKGROUND

Central liver segments resection (CLSR) still is not widely used in pediatric surgery due to its technical difficulty, whereas this procedure is widely spread as a parenchyma sparing approach of centrally located liver tumors in adults. The aim of this study is to analyze the outcomes of CLSR in comparison with extended hepatectomy (EH) in children with different liver tumors.

METHODS

A single-center retrospective analysis of patients who received CLSR (n = 14) and EH (n = 44) from June 2017 to December 2023 was applied. Patient's characteristics, preoperative, intra- and postoperative data were compared between 2 groups.

RESULTS

Preoperative CT-volumetry showed that future liver remnant volume was higher in CLSR group compared to EH (FLR-V; (54 ± 29 (40-91) % vs 40 ± 12 (17-73) %, p = 0.016). The intraoperative blood loss (200 [90-1150] (20-3000) ml vs 100 [30-275] (10-9000) ml, p = 0.088) and transfusion volume (310 [85-590] (0-1860) ml vs 150 [0-310] (0-4770) ml, p = 0.484) were similar in both groups, while operation time was longer in CLSR group (420 [320-595] (145-785) min vs 280 [203-390] (125-710) min), p = 0.011). There was no difference in biliary leakage (3 (21.4 %) vs 12 (27.3 %); p = 0.479), other complications (4 (28.6 %) vs 5 (11.4 %), p = 0.198) and complications ≥ IIIb by Clavien-Dindo (2 (14.3 %) vs 8 (18.2 %), p = 0.385) postoperatively.

CONCLUSION

CLSRs allow to preserve more healthy liver parenchyma compared to EH with similar intraoperative and postoperative outcomes. «Extended mesohepatectomy» allows to achieve R0 resection when central liver tumor extends on the left lateral and/or right posterior section.

TYPE OF STUDY

Retrospective Comparative Study (Level of Evidence III).

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.

In-depth Clinical, Hemodynamic, and Volumetric Assessment of the Resection and Partial Liver Transplantation With Delayed Total Hepatectomy-Type Auxiliary Liver Transplantation in Noncirrhotic Setting: Are We Simply Dealing With a Transplant Model of Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy?

BACKGROUND

The Resection And Partial Liver Transplantation with Delayed total hepatectomy (RAPID) procedure involves left hepatectomy with orthotopic implantation of a left lobe and right portal vein ligation. This technique induces volumetric graft increase, allowing for a right completion hepatectomy within 15 days. Notably, there is a lack of data on the hemodynamics of small-for-size grafts exposed to portal overflow without triggering small-for-size syndrome.

METHODS

A prospective single-center protocol included 8 living donors and 8 RAPID noncirrhotic recipients. Comprehensive clinical and biological data were collected, accompanied by intraoperative arterial and portal flow and pressure measurements. Early kinetic growth rate (eKGR%) and graft function were assessed using computed tomography and 99Tc-mebrofenin scintigraphy on postoperative days 7 and 14. Findings were compared with retrospective data from 13 left living donor liver transplantation (LDLT) recipients.

RESULTS

The median Graft-body weight ratio was 0.41% (interquartile range: 0.34-0.49), markedly lower than in LDLT. However, there was no significant difference in eKGR between RAPID and LDLT grafts. Sequential analysis revealed variable eKGR per day: 10.6% (7.8-13.2) in the first week and 7.6% (6-9.1) in the second week posttransplantation. Indexed portal flow (indexed portal vein flow) was significantly higher in RAPID compared with left LDLT ( P = 0.01). No hemodynamic parameters were found to correlate with regeneration speed. We modulated portal flow in 2 out of 8 cases.

CONCLUSIONS

This study presents the first report of hemodynamic and volumetric data for the RAPID technique. Despite initial graft volumes falling below conventional LDLT recommendations, the study highlights acceptable clinical outcomes.

Transileocolic Portal Vein Embolization Increases Remnant Liver Volume After Major Hepatectomy

BACKGROUND/AIM

Transileocolic portal vein embolization (TIPE) may reduce the risk of liver failure after massive hepatectomy. However, convincing evidence of its usefulness in this regard is yet to be reported. Therefore, this study aimed to investigate the use of TIPE after massive hepatectomy.

PATIENTS AND METHODS

Twelve patients who underwent TIPE were included. Pre- and postoperative liver volumetry was determined using a 3D simulator with computed tomography.

RESULTS

After TIPE, the percent change in total liver volume was 104.0%±13.1% (p=0.08). Conversely, the percent increase in remnant liver volume (ml)/total liver volume (ml) and remnant liver volume (ml)/standard liver volume (ml) was 122.9%±18.6% (p<0.001) and 132.2%±19.6% (p<0.001), respectively. TIPE operation time was 125±84.6 min, with minimal blood loss in all cases. Postoperative hospitalization duration during TIPE was 4.5±2.6 days. No TIPE-related complications occurred in any patient.

CONCLUSION

TIPE is beneficial and safe when preoperative volumetry indicates that the remaining liver volume is inadequate and inoperable.

Preoperative imaging of colorectal liver metastases: what the radiologist and the multidisciplinary team need to know

The management of patients with colorectal liver metastases (CRLM) has transformed over the past 2 decades. Advances in surgical techniques, systemic therapies, and local treatments have resulted in a paradigm shift. Disease that would once have been considered terminal is now frequently treated aggressively with both a disease-free and overall survival benefit. In line with the expanding range of treatment options, there has been an increase in the volume and complexity of imaging required in the management of these patients to ensure optimal patient selection and outcome. The radiologist plays a pivotal role in interpreting these studies, conveying the relevant information and informing the discussion at multidisciplinary team meetings. The purpose of this review is to provide an update for radiologists on the current surgical management of patients with CRLM highlighting specific imaging information that is required by the multidisciplinary team when assessing resectability and/or the need for additional liver-directed therapies.

Comparative study of short-and long-term results in patients with perihilar cholangiocarcinoma undergoing surgical resection: does the extent and side of resection really affect outcome?

BACKGROUND

The surgical management of perihilar carcinoma (pCCA) is still subject of ongoing debate. To provide more clarity, this study was conducted to evaluate outcomes related to the side and extent of heatectomy in patients with pCAA.

METHODS

A total of 32 patients with curative resection for pCCA were identified from our prospective database. Short-and long-term clinical outcome data and histopathological results were compared between right-sided (R-H) and left-sided (L-H) hepatectomy.

RESULTS

Nine patients (28.13%) underwent left-sided hepatectomy while a right-sided hepatectomy was accomplished in 23 patients (71.87%). In the R-H group hepatic conditioning of the future liver remnant (FLR) prior to extended resection was necessary in 13 cases (56.52%), and simultaneous pancreaticoduodenectomy was performed in 5 patients (21.74%). The arterial and portal venous reconstruction rates were 17.39% and 11.11% (P=1.00), and 60.87% and 33.33% (P=0.243) in the R-H and L-H groups, respectively. No statistically significant differences in short-term morbidity and mortality between both groups were observed. The rate of R0 resections was comparable (R-H: 78.26% versus L-H: 66.67%; P=0.654) resulting in similar long-term overall and disease-free survival rates after right-and left hepatectomy.

CONCLUSIONS

In patients with pCCA, both right- and left-sided resections appear to be safe and feasible options with similar postoperative morbidity and oncologic outcomes. Consecutively, the ideal surgical approach should be patient-tailored based on anatomical considerations and the functional future liver capacity.

CIRSE Standards of Practice on Portal Vein Embolization and Double Vein Embolization/Liver Venous Deprivation

This CIRSE Standards of Practice document is aimed at interventional radiologists and provides best practices for performing liver regeneration therapies prior to major hepatectomies, including portal vein embolization, double vein embolization and liver venous deprivation. It has been developed by an expert writing group under the guidance of the CIRSE Standards of Practice Committee. It encompasses all clinical and technical details required to perform liver regeneration therapies, revising the indications, contra-indications, outcome measures assessed, technique and expected outcomes.

Challenges and Opportunities for Precision Surgery for Colorectal Liver Metastases

The incidence of colorectal cancer and colorectal liver metastases (CRLM) is increasing globally due to an interaction of environmental and genetic factors. A minority of patients with CRLM have surgically resectable disease, but for those who have resection as part of multimodal therapy for their disease, long-term survival has been shown. Precision surgery-the idea of careful patient selection and targeting of surgical intervention, such that treatments shown to be proven to benefit on a population level are the optimal treatment for each individual patient-is the new paradigm of care. Key to this is the understanding of tumour molecular biology and clinically relevant mutations, such as KRAS, BRAF, and microsatellite instability (MSI), which can predict poorer overall outcomes and a poorer response to systemic therapy. The emergence of immunotherapy and hepatic artery infusion (HAI) pumps show potential to convert previously unresectable disease to resectable disease, in addition to established systemic and locoregional therapies, but the surgeon must be wary of poor-quality livers and the spectre of post-hepatectomy liver failure (PHLF). Volume modulation, a cornerstone of hepatic surgery for a generation, has been given a shot in the arm with the advent of liver venous depletion (LVD) ensuring significantly more hypertrophy of the future liver remnant (FLR). The optimal timing of liver resection for those patients with synchronous disease is yet to be truly established, but evidence would suggest that those patients requiring complex colorectal surgery and major liver resection are best served with a staged approach. In the operating room, parenchyma-preserving minimally invasive surgery (MIS) can dramatically reduce the surgical insult to the patient and lead to better perioperative outcomes, with quicker return to function.

Effect of Sarcopenia on the Increase in Liver Volume and Function After Portal Vein Embolization

PURPOSE

Sarcopenia is associated with a decreased kinetic growth rate (KGR) of the future liver remnant (FLR) after portal vein embolization (PVE). However, little is known on the increase in FLR function (FLRF) after PVE. This study evaluated the effect of sarcopenia on the functional growth rate (FGR) after PVE measured with hepatobiliary scintigraphy (HBS).

METHODS

All patients who underwent PVE at the Amsterdam UMC between January 2005 and August 2017 were analyzed. Functional imaging by HBS was used to determine FGR. Liver volumetry was performed using multiphase contrast computed tomography (CT). Muscle area measurement to determine sarcopenia was taken at the third lumbar level (L3).

RESULTS

Out of the 95 included patients, 9 were excluded due to unavailable data. 70/86 (81%) patients were sarcopenic. In the multivariate logistic regression analysis, sarcopenia (p = 0.009) and FLR volume (FRLV) before PVE (p = 0.021) were the only factors correlated with KGR, while no correlation was found with FGR. 90-day mortality was similar across the sarcopenic and non-sarcopenic group (4/53 [8%] versus 1/11 [9%]; p = 1.000). The resection rates were also comparable (53/70 [75%] versus 11/16 [69%]; p = 0.542).

CONCLUSION

FGR after PVE as measured by HBS appears to be preserved in sarcopenic patients. This is in contrast to KGR after PVE as measured by liver volumetry which is decreased in sarcopenic patients.

LEVEL OF EVIDENCE

Level 3b, cohort and case control studies.

Which factors predict tumor recurrence and survival after curative hepatectomy in hepatocellular carcinoma? Results from a European institution

BACKGROUND

High tumor recurrence and dismal survival rates after curative intended resection for hepatocellular carcinoma (HCC) are still concerning. The primary goal was to assess predictive factors associated with disease-free (DFS) and overall survival (OS) in a subset of patients with HCC undergoing hepatic resection (HR).

METHODS

Between 08/2004-7/2021, HR for HCC was performed in 188 patients at our institution. Data allocation was conducted from a prospectively maintained database. The prognostic impact of clinico-pathological factors on DFS and OS was assessed by using uni- and multivariate Cox regression analyses. Survival curves were generated with the Kaplan Meier method.

RESULTS

The postoperative 1-, 3- and 5- year overall DFS and OS rates were 77.9%, 49.7%, 41% and 72.7%, 54.7%, 38.8%, respectively. Tumor diameter ≥ 45 mm [HR 1.725; (95% CI 1.091-2.727); p = 0.020], intra-abdominal abscess [HR 3.812; (95% CI 1.859-7.815); p < 0.0001], and preoperative chronic alcohol abuse [HR 1.831; (95% CI 1.102-3.042); p = 0.020] were independently predictive for DFS while diabetes mellitus [HR 1.714; (95% CI 1.147-2.561); p = 0.009), M-Stage [HR 2.656; (95% CI 1.034-6.826); p = 0.042], V-Stage [HR 1.946; (95% CI 1.299-2.915); p = 0.001, Sepsis [HR 10.999; (95% CI 5.167-23.412); p < 0.0001], and ISGLS B/C [HR 2.008; (95% CI 1.273-3.168); p = 0.003] were significant determinants of OS.

CONCLUSIONS

Despite high postoperative recurrence rates, an acceptable long-term survival in patients after curative HR could be achieved. The Identification of parameters related to OS and DFS improves patient-centered treatment and surveillance strategies.

Research progress on asialoglycoprotein receptor-targeted radiotracers designed for hepatic nuclear medicine imaging

Asialoglycoprotein receptor (ASGPR) specifically recognizes glycans terminated with β-d-galactose or N-acetylgalactosamine. Its exclusive expression in mammalian hepatocytes renders it an ideal hepatic-targeted biomarker. To date, ASGPR-targeted ligands have been actively developed for drug delivery and hepatic imaging. This review provides a comprehensive summary of the progress achieved to-date in the field of developing ASGPR-targeted nuclear medicine imaging (NMI) radiotracers, highlighting the recent advancements over the last decade in terms of structure, radionuclides and labeling strategies. The biodistribution patterns, imaging characteristics, challenges and future prospective are discussed.

Assessment of liver function by gadoxetic acid avidity in MRI in a model of rapid liver regeneration in rats

BACKGROUND

This animal study investigates the hypothesis of an immature liver growth following ALPPS (associating liver partition and portal vein ligation for staged hepatectomy) by measuring liver volume and function using gadoxetic acid avidity in magnetic resonance imaging (MRI) in models of ALPPS, major liver resection (LR) and portal vein ligation (PVL).

METHODS

Wistar rats were randomly allocated to ALPPS, LR or PVL. In contrast-enhanced MRI scans with gadoxetic acid (Primovist®), liver volume and function of the right median lobe (=future liver remnant, FLR) and the deportalized lobes (DPL) were assessed until post-operative day (POD) 5. Liver functionFLR/DPL was defined as the inverse value of time from injection of gadoxetic acid to the blood pool-corrected maximum signal intensityFLR/DPL multiplied by the volumeFLR/DPL.

RESULTS

In ALPPS (n = 6), LR (n = 6) and PVL (n = 6), volumeFLR and functionFLR increased proportionally, except on POD 1. Thereafter, functionFLR exceeded volumeFLR increase in LR and ALPPS, but not in PVL. Total liver function was significantly reduced after LR until POD 3, but never undercuts 60% of its pre-operative value following ALPPS and PVL.

DISCUSSION

This study shows for the first time that functional increase is proportional to volume increase in ALPPS using gadoxetic acid avidity in MRI.

Robotic ALPPS for primary and metastatic liver tumours: short-term outcomes versus open approach

Associating Liver Partition and Portal vein ligation for Staged hepatectomy (ALPPS) is one of the strategies available for patients initially unresectable. High risk of peri-operative morbidity and mortality limited its application and diffusion. We aimed to analyse short-term outcomes of robotic ALPPS versus open approach, to assess safety and reproducibility of this technique. A retrospective analysis of prospectively maintained databases at University of Modena and Reggio Emilia on patients that underwent ALPPS between January 2015 and September 2022 was conducted. The main aim of the study was to evaluate safety and feasibility of robotic approach, either full robotic or only first-stage robotic, compared to a control group of patients who underwent open ALPPS in the same Institution. 23 patients were included. Nine patients received a full open ALPPS (O-ALPPS), 7 received a full robotic ALPPS (R-ALPPS), and 7 underwent a robotic approach for stage 1, followed by an open approach for stage 2 (R + O-ALPPS). PHLF grade B-C after stage 1 was 0% in all groups, rising to 58% in the R + O-ALPPS group after stage 2 and remaining 0% in the R-ALPPS group. 86% of R-ALPPS cases were discharged from the hospital between stages 1 and 2, and median total in-hospital stay and ICU stay favoured full robotic approach as well. This contemporary study represents the largest series of robotic ALPPS, showing potential advantages from full robotic ALPPS over open approach, resulting in reduced hospital stay and complications and lower incidence of 90-day mortality.

Free mebrofenin clearance

OBJECTIVES

To determine if three new simplified equations for measurement of free mebrofenin clearance give similar results to the equations defined by Ekman et. al ., and to evaluate the properties of all four methods. Regional mebrofenin clearance has been used to predict future remnant liver function and liver failure after regional liver therapy, such as partial hepatic resection.

METHODS

The means, standard deviations, and correlations of the free mebrofenin clearance measured by the Ekman method and the three simplified methods were compared in a consecutive series of 26 studies in 20 patients. The fractional change in the blood and free mebrofenin activities were compared, and integrals of normalized blood and free mebrofenin ("effective times") were compared.

RESULTS

The average percent free mebrofenin clearance for the Ekman and the first, second and third simplified methods were 13.62 ± 2.88%/min, 12.98 ± 2.97%/min, 12.52 ± 2.81%/min and 15.03 ± 2.27%/min, respectively. The correlations of the new methods with Ekman were 0.97, 0.93 and 0.93. The fractional changes during the measurement interval for the blood and free mebrofenin activities were 0.381 ± 0.065 and 0.329 ± 0.062, difference 0.052, P  < 0.5. The integrals of normalized blood and free mebrofenin activities were 2.566 ± 0.160 min and 2.661 ± 0.158 min, difference of 0.094 min and P  < 0.05.

CONCLUSIONS

The results of the three new methods were similar to the Ekman method. The first simplified method was identified as the lead method for clinical validation in a larger population.

Contemporary Surgical Management of Colorectal Liver Metastases

Colorectal cancer is the third most common cancer in the United States and the second most common cause of cancer-related death. Approximately 20-30% of patients will develop hepatic metastasis in the form of synchronous or metachronous disease. The treatment of colorectal liver metastasis (CRLM) has evolved into a multidisciplinary approach, with chemotherapy and a variety of locoregional treatments, such as ablation and portal vein embolization, playing a crucial role. However, resection remains a core tenet of management, serving as the gold standard for a curative-intent therapy. As such, the input of a dedicated hepatobiliary surgeon is paramount for appropriate patient selection and choice of surgical approach, as significant advances in the field have made management decisions extremely nuanced and complex. We herein aim to review the contemporary surgical management of colorectal liver metastasis with respect to both perioperative and operative considerations.

90Y-/166Ho- 'Radiation lobectomy' for liver tumors induces abnormal morphology and impaired drainage of peritumor lymphatics

Background & Aims

High-dose unilobar radioembolization, or 'radiation lobectomy' (RL), is an induction therapy that achieves contralateral future liver remnant hypertrophy while simultaneously irradiating the tumor. As such, it may prevent further growth, but it is unknown whether RL affects intrahepatic lymphatics, a major route via which liver tumors disseminate.

Methods

This was a case-control study conducted at University Medical Center Utrecht. The study compared lymph vessels in livers that had undergone RL (cases) with those in livers that had not undergone RL (controls). Histological samples were acquired from patients diagnosed with hepatocellular carcinoma (HCC) or colorectal liver metastases (CRLM) between 2017 and 2022. Lymph vessel morphology was analyzed by two researchers using podoplanin, a protein that is expressed in lymphatic endothelium. In vivo liver lymph drainage of radioembolized livers was assessed using intraoperative liver lymphangiography (ILL): during liver surgery, patent blue dye was injected into the liver parenchyma, followed by inspection for staining of perihepatic lymph structures. ILL results were compared to a previously published cohort.

Results

Immunohistochemical analysis on post-RL tumor tissues from ten patients with CRLM and nine patients with HCC revealed aberrant morphology of irradiated liver lymphatics when compared to controls (n = 3 per group). Irradiated lymphatics were tortuous (p <0.05), thickened (p <0.05) and discontinuous (p <0.05). Moreover, post-RL lymphatics had larger lumens (1.5-1.7x, p <0.0001), indicating lymph stasis. ILL revealed diminished lymphatic drainage to perihepatic lymph nodes and vessels in irradiated livers when compared to non-radioembolized controls (p = 1.0x10-4).

Conclusions

Radioembolization impairs peritumoral lymph vessel function. Further research is needed to evaluate if radioembolization impairs tumor dissemination via this route.

Impact and implications

Unilobar radioembolization can serve as an alternative to portal venous embolization for patients who are considered unresectable due to an insufficient future liver remnant. This research suggests that radioembolization impairs the function of peritumoral liver lymph vessels, potentially hindering dissemination via this route. These findings provide support for considering unilobar radioembolization over standard portal venous embolization.

Resection Versus Transplant for Hepatocellular Carcinoma: How to Offer the Best Modality

Liver resection and liver transplantation are the mainstay of treatment for patients with hepatocellular carcinoma. Patient comorbidities, tumor resectability, and perioperative morbidity and mortality risk, specifically of post-hepatectomy liver failure, are determining factors when deciding between liver resection and liver transplantation in patients who do not have an obvious contraindication to either treatment. Liver resection is preferred in patients without cirrhosis, and it may be a reasonable choice in patient with cirrhosis but preserved liver function and no portal hypertension if the size and function of the future liver remnant are appropriate, especially if organ availability is scarce.

Assessing regional hepatic function changes after hypertrophy induction by radioembolisation: comparison of gadoxetic acid-enhanced MRI and 99mTc-mebrofenin hepatobiliary scintigraphy

BACKGROUND

To compare Gd-ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) and 99mTc-labelled mebrofenin hepatobiliary scintigraphy (HBS) as imaging-based liver function tests after unilateral radioembolisation (RE) in patients with primary or secondary liver malignancies.

METHODS

Twenty-three patients with primary or secondary liver malignancies who underwent Gd-EOB-DTPA-enhanced MRI within a prospective study (REVoluTion) were evaluated. REVoluTion was a prospective open-label, non-randomised, therapy-optimising study of patients undergoing right-sided or sequential RE for contralateral liver hypertrophy at a single centre in Germany. MRI and hepatobiliary scintigraphy were performed before RE (baseline) and 6 weeks after (follow-up). This exploratory subanalysis compared liver enhancement on hepatobiliary phase MRI normalised to the spleen (liver-to-spleen ratio (LSR)) and the muscle (liver-to-muscle ratio (LMR)) with mebrofenin uptake on HBS for the total liver (TL) and separately for the right (RLL) and left liver lobe (LLL).

RESULTS

Mebrofenin uptake at baseline and follow-up each correlated significantly with LSR and LMR on MRI for TL (≤ 0.013) and RLL (≤ 0.049). Regarding the LLL, mebrofenin uptake correlated significantly with LMR (baseline, p = 0.013; follow-up, p = 0.004), whereas with LSR, a borderline significant correlation was only seen at follow-up (p = 0.051; p = 0.046).

CONCLUSION

LSRs and LMR correlate with mebrofenin uptake in HBS. This study indicates that Gd-EOB-DTPA-enhanced MRI and 99mTc-labelled mebrofenin HBS may equally be used to assess an increase in contralateral liver lobe function after right-sided RE.

RELEVANCE STATEMENT

MRI may be a convenient and reliable method for assessing the future liver remnant facilitating treatment planning and monitoring of patients after RE-induced hypertrophy induction.

KEY POINTS

• Both MRI and HBS can assess liver function after RE. • Liver enhancement on MRI correlates with mebrofenin uptake on HBS. • MRI might be a convenient alternative for estimating future liver remnants after hypertrophy induction.

Tc-99m mebrofenin hepatobiliary scintigraphy to assess future liver remnant function before major liver surgery

BACKGROUND AND OBJECTIVES

Assessment of liver function is paramount before hepatectomy. This study aimed to assess future liver remnant function (FLR-F) using hepatobiliary scintigraphy (HBS) and to compare it to FLR volume (FLR-V) in the prediction of posthepatectomy liver failure (PHLF). The impact of volume and function gains were also assessed in patients undergoing portal vein embolization (PVE) or liver venous deprivation (LVD).

METHODS

All consecutive patients undergoing major hepatectomy between 02/2018 and 09/2021 with preoperative HBS were included. FLR-V was expressed as percentage of total liver volume and analyzed using preoperative computed tomography. FLR-V and FLR-F gains after embolization were expressed in percentage. Receiver operating characteristic analysis was performed to compare both methods in predicting PHLF.

RESULTS

Thirty-six patients were included. PVE and LVD were performed in 4 (11%) and 28 patients (78%), respectively. Overall, PHLF occurred in eight patients (22%). FLR-F gain after embolization showed significant ability to predict PHLF (area under the curve [AUC] = 0.789), with cut-off value of 150% showing a sensitivity of 1.00, a specificity of 0.42, and a negative predictive value of 1.00.

CONCLUSION

Preoperative HBS shows a high sensitivity to predict PHLF when HBS is performed twice to measure the function gain after venous embolization.

Single-Center Retrospective Study Comparing Double Vein Embolization via a Trans-Jugular Approach with Liver Venous Deprivation via a Trans-Hepatic Approach

PURPOSE

To compare safety, technical and clinical outcomes of double vein embolization (DVE) via a trans-jugular approach with liver venous deprivation (LVD) via a trans-hepatic approach.

MATERIALS AND METHODS

A single-center retrospective analysis was conducted on patients undergoing simultaneous portal and hepatic veins embolization in view of a major hepatectomy (June 2019-November 2022). Hepatic vein embolization was performed either by transjugular plug (DVE) or by transhepatic plug followed by glue injection (LVD). Inclusion criteria were availability of pre-procedural CT scan, and availability of CT scans acquired 10 days and 25 days post-procedure. Comparative data included complication rate, fluoroscopy time, dose area product (DAP), Future Liver Remnant volume and function increase (FLR-V and FLR-F increase, respectively) and clinical outcomes.

RESULTS

Thirty-six patients (n = 14 DVE; n = 22 LVD) were included. No baseline significant differences were observed among the two groups. One grade-3 complication (2.8%) was observed in the LVD group; one case of technical failure (2.8%) was observed in the DVE group. Fluoroscopy time and DAP were similar between DVE and LVD (29 ± 17.7 vs. 25 ± 8.2 min, p = 0.97; 105.1 ± 63.5 vs. 143.4 ± 79.5 Gy·cm2, p = 0.15). No differences arose at either time-point in FLR-V increase (46.7 ± 23.1% vs. 48.2 ± 28.2%, 52.9 ± 30.9% vs. 53.2 ± 29%, respectively, p = 0.9). FLR-F increase also did not differ significantly (62.8 ± 55.2 vs. 67.4 ± 57.5, p = 0.9). No differences in drop-out rate from surgery were observed. (28.6% vs. 27.3%, p = 0.93). One case of grade-B post-hepatectomy liver failure (2.8%) was observed in the LVD group.

CONCLUSION

LVD via transhepatic approach and DVE via transjugular approach seem equally safe and effective. Level of Evidence Level 3, Retrospective Cohort Study.

Joint EANM/SNMMI/IHPBA procedure guideline for [99mTc]Tc-mebrofenin hepatobiliary scintigraphy SPECT/CT in the quantitative assessment of the future liver remnant function

PURPOSE

The aim of this joint EANM/SNMMI/IHPBA procedure guideline is to provide general information and specific recommendations and considerations on the use of [99mTc]Tc-mebrofenin hepatobiliary scintigraphy (HBS) in the quantitative assessment and risk analysis before surgical intervention, selective internal radiation therapy (SIRT) or before and after liver regenerative procedures. Although the gold standard to estimate future liver remnant (FLR) function remains volumetry, the increasing interest in HBS and the continuous request for implementation in major liver centers worldwide, demands standardization.

METHODS

This guideline concentrates on the endorsement of a standardized protocol for HBS elaborates on the clinical indications and implications, considerations, clinical appliance, cut-off values, interactions, acquisition, post-processing analysis and interpretation. Referral to the practical guidelines for additional post-processing manual instructions is provided.

CONCLUSION

The increasing interest of major liver centers worldwide in HBS requires guidance for implementation. Standardization facilitates applicability of HBS and promotes global implementation. Inclusion of HBS in standard care is not meant as substitute for volumetry, but rather to complement risk evaluation by identifying suspected and unsuspected high-risk patients prone to develop post-hepatectomy liver failure (PHLF) and post-SIRT liver failure.

E-AHPBA-ESSO-ESSR Innsbruck consensus guidelines for preoperative liver function assessment before hepatectomy

BACKGROUND

Posthepatectomy liver failure (PHLF) contributes significantly to morbidity and mortality after liver surgery. Standardized assessment of preoperative liver function is crucial to identify patients at risk. These European consensus guidelines provide guidance for preoperative patient assessment.

METHODS

A modified Delphi approach was used to achieve consensus. The expert panel consisted of hepatobiliary surgeons, radiologists, nuclear medicine specialists, and hepatologists. The guideline process was supervised by a methodologist and reviewed by a patient representative. A systematic literature search was performed in PubMed/MEDLINE, the Cochrane library, and the WHO International Clinical Trials Registry. Evidence assessment and statement development followed Scottish Intercollegiate Guidelines Network methodology.

RESULTS

Based on 271 publications covering 4 key areas, 21 statements (at least 85 per cent agreement) were produced (median level of evidence 2- to 2+). Only a few systematic reviews (2++) and one RCT (1+) were identified. Preoperative liver function assessment should be considered before complex resections, and in patients with suspected or known underlying liver disease, or chemotherapy-associated or drug-induced liver injury. Clinical assessment and blood-based scores reflecting liver function or portal hypertension (for example albumin/bilirubin, platelet count) aid in identifying risk of PHLF. Volumetry of the future liver remnant represents the foundation for assessment, and can be combined with indocyanine green clearance or LiMAx® according to local expertise and availability. Functional MRI and liver scintigraphy are alternatives, combining FLR volume and function in one examination.

CONCLUSION

These guidelines reflect established methods to assess preoperative liver function and PHLF risk, and have uncovered evidence gaps of interest for future research.

Comparing Liver Venous Deprivation and Portal Vein Embolization for Perihilar Cholangiocarcinoma: Is It Time to Shift the Focus to Hepatic Functional Reserve Rather than Hypertrophy?

Purpose: Among liver hypertrophy technics, liver venous deprivation (LVD) has been recently introduced as an effective procedure to combine simultaneous portal inflow and hepatic outflow abrogation, raising growing clinical interest. The aim of this study is to investigate the role of LVD for preoperative optimization of future liver remnant (FLR) in perihilar cholangiocarcinoma (PHC), especially when compared with portal vein embolization (PVE). Methods: Between January 2013 and July 2022, all patients diagnosed with PHC and scheduled for preoperative optimization of FTR, through radiological hypertrophy techniques, prior to liver resection, were included. FTR volumetric assessment was evaluated at two distinct timepoints to track the progression of both early (T1, 10 days post-procedural) and late (T2, 21 days post-procedural) efficacy indicators. Post-procedural outcomes, including functional and volumetric analyses, were compared between the LVD and the PVE cohorts. Results: A total of 12 patients underwent LVD while 19 underwent PVE. No significant differences in either post-procedural or post-operative complications were found. Post-procedural FLR function, calculated with (99m) Tc-Mebrofenin hepatobiliary scintigraphy, and kinetic growth rate, at both timepoints, were greater in the LVD cohort (3.12 ± 0.55%/min/m2 vs. 2.46 ± 0.64%/min/m2, p = 0.041; 27.32 ± 16.86%/week (T1) vs. 15.71 ± 9.82%/week (T1) p < 0.001; 17.19 ± 9.88%/week (T2) vs. 9.89 ± 14.62%/week (T2) p = 0.034) when compared with the PVE cohort. Post-procedural FTR volumes were similar for both hypertrophy techniques. Conclusions: LVD is an effective procedure to effectively optimize FLR before liver resection for PHC. The faster growth rate combined with the improved FLR function, when compared to PVE alone, could maximize surgical outcomes by lowering post-hepatectomy liver failure rates.

How Much Is Enough? A Surgical Perspective on Imaging Modalities to Estimate Function and Volume of the Future Liver Remnant before Hepatic Resection

Liver resection is the first curative option for most hepatic primary and secondary malignancies. However, post-hepatectomy liver failure (PHLF) still represents a non-negligible postoperative complication, embodying the most frequent cause of hepatic-related mortality. In the absence of a specific treatment, the most effective way to deal with PHLF is its prevention through a careful preoperative assessment of future liver remnant (FLR) volume and function. Apart from the clinical score and classical criteria to define the safe limit of resectability, new imaging modalities have shown their ability to assist surgeons in planning the best operative strategy with a precise estimation of the FLR amount. New technologies leading to liver and tumor 3D reconstruction may guide the surgeon along the best resection planes combining the least liver parenchymal sacrifice with oncological appropriateness. Integration with imaging modalities, such as hepatobiliary scintigraphy, capable of estimating total and regional liver function, may bring about a decrease in postoperative complications. Magnetic resonance imaging with hepatobiliary contrast seems to be predominant since it simultaneously integrates hepatic function and volume information along with a precise characterization of the target malignancy.

Dose finding study for unilobar radioembolization using holmium-166 microspheres to improve resectability in patients with HCC: the RALLY protocol

BACKGROUND

High dose unilobar radioembolization (also termed 'radiation lobectomy')-the transarterial unilobar infusion of radioactive microspheres as a means of controlling tumour growth while concomitantly inducing future liver remnant hypertrophy-has recently gained interest as induction strategy for surgical resection. Prospective studies on the safety and efficacy of the unilobar radioembolization-surgery treatment algorithm are lacking. The RALLY study aims to assess the safety and toxicity profile of holmium-166 unilobar radioembolization in patients with hepatocellular carcinoma ineligible for surgery due to insufficiency of the future liver remnant.

METHODS

The RALLY study is a multicenter, interventional, non-randomized, open-label, non-comparative safety study. Patients with hepatocellular carcinoma who are considered ineligible for surgery due to insufficiency of the future liver remnant (< 2.7%/min/m2 on hepatobiliary iminodiacetic acid scan will be included. A classical 3 + 3 dose escalation model will be used, enrolling three to six patients in each cohort. The primary objective is to determine the maximum tolerated treated non-tumourous liver-absorbed dose (cohorts of 50, 60, 70 and 80 Gy). Secondary objectives are to evaluate dose-response relationships, to establish the safety and feasibility of surgical resection following unilobar radioembolization, to assess quality of life, and to generate a biobank.

DISCUSSION

This will be the first clinical study to assess the unilobar radioembolization-surgery treatment algorithm and may serve as a stepping stone towards its implementation in routine clinical practice.

TRIAL REGISTRATION

Netherlands Trial Register NL8902 , registered on 2020-09-15.

The value of intraoperative dynamic liver function test ICG in predicting postoperative complications in patients undergoing staged hepatectomy: a pilot study

PURPOSE

To assess the predictive value of intraoperative indocyanine green (ICG) test in patients undergoing staged hepatectomy.

METHODS

We analyzed intraoperative ICG measurements of future liver remnant (FLR), preoperative ICG, volumetry, and hepatobiliary scintigraphy in 15 patients undergoing associated liver partition and portal vein ligation for staged hepatectomy (ALPPS). Main endpoints were the correlation of intraoperative ICG values to postoperative complications (Comprehensive Complication Index (CCI®)) at discharge and 90 days after surgery, and to postoperative liver function.

RESULTS

Median intraoperative R15 (ICG retention rate at 15 min) correlated significantly with CCI® at discharge (p = 0.05) and with CCI® at 90 days (p = 0.0036). Preoperative ICG, volumetry, and scintigraphy did not correlate to postoperative outcome. ROC curve analysis revealed a cutoff value of 11.4 for the intraoperative R15 to predict major complications (Clavien-Dindo ≥ III) with 100% sensitivity and 63% specificity. No patient with R15 ≤ 11 developed major complications.

CONCLUSION

This pilot study suggests that intraoperative ICG clearance determines the functional capacity of the future liver remnant more accurately than preoperative tests. This may further reduce the number of postoperative liver failures, even if it means intraoperative abortion of hepatectomy in individual cases.

Role of Preoperative Hepatobiliary Scintigraphy in Children Requiring Liver Resection

PURPOSE

The risk of posthepatectomy liver failure (PHLF) remains an important concern following major liver resection. Assessment of future remnant liver function (FRLF) by hepatobiliary scintigraphy has shown its significance to prevent PHLF after major liver resection in adults with a threshold value of FRLF greater than 2.7%/min per m2. However, such data for pediatric patients were not published.

METHODS

A total of 77 pediatric patients with liver tumors who underwent 1-stage liver resection were included in this study. Assessment of FRLF, future remnant liver volume (FRLV), and the ratio of remnant liver volume to body weight (RLV-BWR) was performed before the surgery.

RESULTS

All patients had RLV-BWR values of more than 0.5%/kg. Future remnant liver volume values ranged from 19% to 89%, and FRLF values ranged from 1.8% to 31.8%/min per m2. Only 7 of 77 patients had FRLV values less than 25%, but their FRLF values exceeded 2.7%/min per m2. Two patients developed grade A and grade B PHLF.

CONCLUSION

Future remnant liver volume and the RLV-BWR can be used in most pediatric patients for the assessment of liver before hepatectomy. According to our data, implementation of FRLF assessment using hepatobiliary scintigraphy can be most beneficial for children with FRLV of less than 25%. The cutoff value of FRLV greater than 25% can be slightly decreased with minimal risk of developing PHLF. However, to establish a new cutoff value for FRLV in children, further prospective studies including larger numbers of patients with FRLV of less than 25% are needed.

Evolution of minimally invasive techniques and surgical outcomes of ALPPS in Italy: a comprehensive trend analysis over 10 years from a national prospective registry

BACKGROUND

Since 2012, Associating Liver Partition and Portal vein ligation for Staged hepatectomy (ALPPS) has encountered several modifications of its original technique. The primary endpoint of this study was to analyze the trend of ALPPS in Italy over a 10-year period. The secondary endpoint was to evaluate factors affecting the risk of morbidity/mortality/post-hepatectomy liver failure (PHLF).

METHODS

Data of patients submitted to ALPPS between 2012 and 2021 were identified from the ALPPS Italian Registry and evaluation of time trends was performed.

RESULTS

From 2012 to 2021, a total of 268 ALPPS were performed within 17 centers. The number of ALPPS divided by the total number of liver resections performed by each center slightly declined (APC = - 2.0%, p = 0.111). Minimally invasive (MI) approach significantly increased over the years (APC = + 49.5%, p = 0.002). According to multivariable analysis, MI completion of stage 1 was protective against 90-day mortality (OR = 0.05, p = 0.040) as well as enrollment within high-volume centers for liver surgery (OR = 0.32, p = 0.009). Use of interstage hepatobiliary scintigraphy (HBS) and biliary tumors were independent predictors of PHLF.

CONCLUSIONS

This national study showed that use of ALPPS only slightly declined over the years with an increased use of MI techniques, leading to lower 90-day mortality. PHLF still remains an open issue.

Laparoscopic Right Hemihepatectomy after Future Liver Remnant Modulation: A Single Surgeon's Experience

BACKGROUND

Laparoscopic right hemihepatectomy (L-RHH) is still considered a technically complex procedure, which should only be performed by experienced surgeons in specialized centers. Future liver remnant modulation (FLRM) strategies, including portal vein embolization (PVE), and associating liver partition and portal vein ligation for staged hepatectomy (ALPPS), might increase the surgical difficulty of L-RHH, due to the distortion of hepatic anatomy, periportal inflammation, and fibrosis. Therefore, this study aims to evaluate the safety and feasibility of L-RHH after FLRM, when compared with ex novo L-RHH.

METHODS

All consecutive right hemihepatectomies performed by a single surgeon in the period between October 2007 and March 2023 were retrospectively analyzed. The patient characteristics and perioperative outcomes of L-RHH after FLRM and ex novo L-RHH were compared.

RESULTS

A total of 59 patients were included in the analysis, of whom 33 underwent FLRM. Patients undergoing FLRM prior to L-RHH were most often male (93.9% vs. 42.3%, p < 0.001), had an ASA-score >2 (45.5% vs. 9.5%, p = 0.006), and underwent a two-stage hepatectomy (45.5% vs. 3.8% p < 0.001). L-RHH after FLRM was associated with longer operative time (median 360 vs. 300 min, p = 0.008) and Pringle duration (31 vs. 24 min, p = 0.011). Intraoperative blood loss, unfavorable intraoperative incidents, and conversion rates were similar in both groups. There were no significant differences in length of hospital stay and 30-day overall and severe morbidity rates. Radical resection margin (R0) and textbook outcome rates were equal. One patient who underwent an extended RHH in the FLRM group deceased within 90 days of surgery, due to post-hepatectomy liver failure.

CONCLUSION

L-RHH after FLRM is more technically complex than L-RHH ex novo, as objectified by longer operative time and Pringle duration. Nevertheless, this procedure appears safe and feasible in experienced hands.

Pushing the Limits of Surgical Resection in Colorectal Liver Metastasis: How Far Can We Go?

Colorectal cancer is the third most common cancer worldwide, and up to 50% of all patients diagnosed will develop metastatic disease. Management of colorectal liver metastases (CRLM) has been constantly improving, aided by newer and more effective chemotherapy agents and the use of multidisciplinary teams. However, the only curative treatment remains surgical resection of the CRLM. Although survival for surgically resected patients has shown modest improvement, this is mostly because of the fact that what is constantly evolving is the indication for resection. Surgeons are constantly pushing the limits of what is considered resectable or not, thus enhancing and enlarging the pool of patients who can be potentially benefited and even cured with aggressive surgical procedures. There are a variety of procedures that have been developed, which range from procedures to stimulate hepatic growth, such as portal vein embolization, two-staged hepatectomy, or the association of both, to technically challenging procedures such as simultaneous approaches for synchronous metastasis, ex-vivo or in-situ perfusion with total vascular exclusion, or even liver transplant. This article reviewed the major breakthroughs in liver surgery for CRLM, showing how much has changed and what has been achieved in the field of CRLM.

Hepatobiliary scintigraphy to predict postoperative liver failure after major liver resection; a multicenter cohort study in 547 patients

BACKGROUND

This study aimed to analyze the predictive value of Hepatobiliary scintigraphy (HBS) for posthepatectomy liver failure (PHLF) after major liver resection with a comparison to assessment of liver volume in a multicenter cohort.

METHODS

Patients who underwent liver resection after HBS were included from six centers. Remnant liver volume was calculated from CT images. PHLF was scored and graded according to the grade B/C ISGLS criteria.

RESULTS

In 547 patients PHLF incidence was 10% (56/547) and 90-day mortality rate 8% (42/547). Overall predictive value of remnant liver function was 0.66 (0.58-0.74) and similar to that of remnant volume (0.63 (0.72). For biliary tumors, a function cut-off of 2.7%/min/m2 and 30% volume cut-off resulted in a PHLF rate 12% and 13%, respectively. While an 8.5%/min (4.5%/min/m2) function cut-off resulted in 7% PHLF for those with a function above the cutoff while a 40% volume cutoff still resulted in 14% PHLF rate. In the multivariable analyses for PHLF, liver function was predictive but liver volume was not.

CONCLUSION

The current study shows that preoperative liver function assessment using HBS is at least as predictive for PHLF as liver volume assessment, and likely has several advantages, particularly in the high-risk sub-group of biliary tumors.

Prediction of left lobe hypertrophy after right lobe radioembolization of the liver using a clinical data model with external validation

In cirrhotic patients with hepatocellular carcinoma (HCC), right-sided radioembolization (RE) with Yttrium-90-loaded microspheres is an established palliative therapy and can be considered a "curative intention" treatment when aiming for sequential tumor resection. To become surgical candidate, hypertrophy of the left liver lobe to > 40% (future liver remnant, FLR) is mandatory, which can develop after RE. The amount of radiation-induced shrinkage of the right lobe and compensatory hypertrophy of the left lobe is difficult for clinicians to predict. This study aimed to utilize machine learning to predict left lobe liver hypertrophy in patients with HCC and cirrhosis scheduled for right lobe RE, with external validation. The results revealed that machine learning can accurately predict relative and absolute volume changes of the left liver lobe after right lobe RE. This prediction algorithm could help to estimate the chances of conversion from palliative RE to curative major hepatectomy following significant FLR hypertrophy.

Locoregional Therapy in the Management of Intrahepatic Cholangiocarcinoma: Is There Sufficient Evidence to Guide Current Clinical Practice?

PURPOSE OF REVIEW

Intrahepatic cholangiocarcinoma (iCCA) carries a dismal prognosis and, despite increasing incidence, still lacks effective treatments. In this scenario, locoregional therapies (LRT) are gaining interest as they may be effective at local tumor control and complementary to surgical and non-surgical approaches. In this article, we will review the evolving role of LRT performed by interventional radiologists in the management of iCCA.

RECENT FINDINGS

Accumulating retrospective evidence indicates that ablative therapies and transarterial embolizations are of benefit for iCCA with unresectable disease, demonstrating promising safety profiles and prolonged or comparable survival outcomes compared to systemic therapy and surgery. Additionally, for surgical candidates, portal ± hepatic venous embolization can improve the safety of hepatectomy by inducing preoperative hypertrophy of the non-involved liver lobe. LRTs are playing an increasingly important role in the multimodal treatment of iCCA from various perspectives with reduced toxicity relative to traditional treatments. To expand the scope of applications for LRTs in this setting, future prospective randomized studies are needed to confirm their efficacy and advantage.

Volume and flow modulation strategies to mitigate post-hepatectomy liver failure

INTRODUCTION

Post hepatectomy liver failure is the most common cause of death following major hepatic resections with a perioperative mortality rate between 40% to 60%. Various strategies have been devised to increase the volume and function of future liver remnant (FLR). This study aims to review the strategies used for volume and flow modulation to reduce the incidence of post hepatectomy liver failure.

METHOD

An electronic search was performed of the MEDLINE, EMBASE and PubMed databases from 2000 to 2022 using the following search strategy "Post hepatectomy liver failure", "flow modulation", "small for size flow syndrome", "portal vein embolization", "dual vein embolization", "ALPPS" and "staged hepatectomy" to identify all articles published relating to this topic.

RESULTS

Volume and flow modulation strategies have evolved over time to maximize the volume and function of FLR to mitigate the risk of PHLF. Portal vein with or without hepatic vein embolization/ligation, ALPPS, and staged hepatectomy have resulted in significant hypertrophy and kinetic growth of FLR. Similarly, techniques including portal flow diversion, splenic artery ligation, splenectomy and pharmacological agents like somatostatin and terlipressin are employed to reduce the risk of small for size flow syndrome SFSF syndrome by decreasing portal venous flow and increasing hepatic artery flow at the same time.

CONCLUSION

The current review outlines the various strategies of volume and flow modulation that can be used in isolation or combination in the management of patients at risk of PHLF.

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.

Quantitative Assessment of Liver Impairment in Chronic Viral Hepatitis with [99mTc]Tc-Mebrofenin: A Noninvasive Attempt to Stage Viral Hepatitis-Associated Liver Fibrosis

Background and objectives—Chronic viral hepatitis B and C infections are one of the leading causes of chronic liver impairment, resulting in liver fibrosis and liver cirrhosis. An early diagnosis with accurate liver fibrosis staging leads to a proper diagnosis, thus tailoring correct treatment. Both invasive and noninvasive techniques are used in the diagnosis and staging of chronic liver impairment. Those techniques include liver biopsy, multiple serological markers (as either single tests or combined panels), and imaging examinations, such as ultrasound or magnetic resonance elastography. Nuclear medicine probes may also be employed in staging liver fibrosis, although the literature scarcely reports this. The purpose of our study was to investigate whether a dynamic liver scintigraphy with [^99mTc]Tc-mebrofenin has any value in staging or grading chronic liver damage. Materials and Methods—We prospectively enrolled patients with chronic viral hepatitis B and C infection referred for liver biopsy. All patient underwent dynamic liver scintigraphy with 99mTc-mebrofenin prior to liver biopsy. Dynamic liver scintigraphy was performed immediately after intravenous tracer injection for 30 min scanning time. Multiple scintigraphy parameters were calculated (whole liver lobe and focal area time to peak (TTP), 30 min to peak ratio (30/peak), whole lobe and focal area slope index in 350 s (slope_350). Liver biopsy took place shortly after imaging. Results—We found that many dynamic scintigraphic parameters are positively or negatively associated with different stages of liver fibrosis. The main parameters that showed most value are the ratio between 30 min and the peak of the dynamic curve (30/peak_dex (ratio)), and liver clearance corrected for body surface area and liver area (LCL_m²_dm² (%/min/m²/dm²)). Conclusions—Our present study proves that conducting dynamic liver scintigraphies with [^99mTc]Tc-mebrofenin has potential value in staging liver fibrosis. The benefits of this method, including whole liver imaging and direct imaging of the liver function, provide an advantage over presently used quantitative imaging modalities.

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.

Dragon 1 Protocol Manuscript: Training, Accreditation, Implementation and Safety Evaluation of Portal and Hepatic Vein Embolization (PVE/HVE) to Accelerate Future Liver Remnant (FLR) Hypertrophy

STUDY PURPOSE

The DRAGON 1 trial aims to assess training, implementation, safety and feasibility of combined portal- and hepatic-vein embolization (PVE/HVE) to accelerate future liver remnant (FLR) hypertrophy in patients with borderline resectable colorectal cancer liver metastases.

METHODS

The DRAGON 1 trial is a worldwide multicenter prospective single arm trial. The primary endpoint is a composite of the safety of PVE/HVE, 90-day mortality, and one year accrual monitoring of each participating center. Secondary endpoints include: feasibility of resection, the used PVE and HVE techniques, FLR-hypertrophy, liver function (subset of centers), overall survival, and disease-free survival. All complications after the PVE/HVE procedure are documented. Liver volumes will be measured at week 1 and if applicable at week 3 and 6 after PVE/HVE and follow-up visits will be held at 1, 3, 6, and 12 months after the resection.

RESULTS

Not applicable.

CONCLUSION

DRAGON 1 is a prospective trial to assess the safety and feasibility of PVE/HVE. Participating study centers will be trained, and procedures standardized using Work Instructions (WI) to prepare for the DRAGON 2 randomized controlled trial. Outcomes should reveal the accrual potential of centers, safety profile of combined PVE/HVE and the effect of FLR-hypertrophy induction by PVE/HVE in patients with CRLM and a small FLR.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT04272931 (February 17, 2020). Toestingonline.nl: NL71535.068.19 (September 20, 2019).