Perioperative Non-Invasive Indocyanine Green-Clearance Testing to Predict Postoperative Outcome after Liver Resection

Advantages and rational application of indocyanine green fluorescence in pulmonary nodule surgery: a narrative review

Background and Objective

The early detection and early treatment of high-risk pulmonary nodules directly affect the long-term survival rate of patients. However, conventional nodule localization methods, such as hook-wire, technetium-99m, and methylene blue are associated with issues such as a high-frequency of complications, low patient tolerance, serious side effects, and inability to identify pigmented lungs. For patients who require segmentectomy, there is often a lack of effective path planning, resulting in insufficient resection margins or excessive loss of lung function. Therefore, effective and rational nodule localization and surgical approaches are crucial. This narrative review aimed to evaluate the advantages of indocyanine green (ICG) fluorescence in pulmonary nodule surgery and clarify its application in various types of patients.

Methods

We searched the PubMed and Web of Science databases from January 2010 to January 2024 using the terms "localization of pulmonary nodules", "localization of pulmonary nodules AND indocyanine green", "localization of pulmonary nodules AND complication", "localization of pulmonary nodules AND surgical planning", and "localization of pulmonary nodules AND underlying lung disease". Information used to write this narrative review was from clinical phenomena, statistical data, and authors' conclusions.

Key Content and Findings

The commonly used localization methods of pulmonary nodule such as computed tomography (CT)-guided percutaneous placement of hook-wire are accompanied with serious complications: including hemopneumothorax and ache. Meanwhile, routine dye commonly fails to localize the nodules in patients with anthracosis. ICG with the enhanced permeability and retention (EPR) effect can be used effectively for preoperative and intraoperative localization of pulmonary nodules and its nature of allowing the observance of the condition of pulmonary blood vessels has gradually become a hotspot of research in this field.

Conclusions

For nodules with a depth of less than 1 cm, no penetration depth problem is encountered when ICG fluorescence is used. Percutaneous puncture can effectively identify the location of nodules at low cost. Compared with other localization methods, it can effectively avoid problems such as pain, radiation exposure, marker displacement, and the existence of anthrax lesions in the lungs. For patients on whom it is difficult to locate nodules due to tissue results, virtual bronchoscopy or electromagnetic navigation bronchoscopy can effectively identify nodules and reduce complications such as pneumothorax. For patients whose operation is postponed due to fever, sudden cardiovascular and cerebrovascular diseases, there is no risk of nodule localization material detachment by using ICG. ICG can also be used in patients with pulmonary physiological or pathological diseases. Meanwhile, in patients with deep pulmonary nodules, ICG fluorescence can help plan the surgical path, ensure the margin of resection, reduce lung function damage, and prevent bronchial fistula. Therefore, the rational use of ICG fluorescence technology can effectively locate nodules, assist surgeons in planning surgical methods, potentially reducing complications and ultimately improving patient prognosis.

Indocyanine Green and Hepatobiliary Surgery: An Overview of the Current Literature

Indocyanine green (ICG) is an inert polypeptide that almost totally binds to high molecular weight plasma proteins; it is cleared by the hepatocytes and directly excreted into the bile with a half-life of about 3-5 minutes. Specific systems are required to see fluorescent images. The use of this dye has been reported in different surgical specialties, and the applications in hepatobiliary surgery are widening. Being firstly used to evaluate the preoperative liver function, intra- and postoperative dynamic checking of hepatic activity has been reported and integrated within perioperative protocols allowing a tailored treatment allocation. Intravenous injection (IV) or injection into the gallbladder can ease difficult cholecystectomy. Biliary leakage detection could be enhanced by IV ICG injection. Although with some contrasting results, the use of ICG for both delineating the limits of the resection and tumor-enhanced visualization was demonstrated to improve short- and long-term outcomes. Although the lack of strong evidence still precludes the introduction of this tool in clinical practice, it harbors great potential in liver surgery.

The link between high factor VIII to protein C ratio values and poor liver function after major hepatectomy

Our goal was to assess the coagulation profile in the immediate postoperative time after major liver surgery and its association with the liver function. Our hypothesis is that a decreased synthesis of the coagulation factor levels reflects an impaired liver synthesis following hepatic resection and will be associated with poor outcomes. This is a prospective, observational study recruiting consecutive patients scheduled for major liver resection in a tertiary hospital. Coagulation profile was assessed by conventional assays, viscoelastic assays and coagulation factor levels preoperatively and, on postoperative days 1, 2 and 6. Factor VIII to protein C (FVIII/PC) ratio has been used as a surrogate marker of hemostatic imbalance. Liver function was measured with conventional and indocyanine green (ICG) clearance tests, which were obtained preoperatively and on postoperative days 1 and 2. Sixty patients were recruited and 51 were included in the study. There is a clear increase in FVIII/PC ratio after surgery, which was significantly associated with low liver function, being more pronounced beyond postoperative day 2 and in patients with poorer liver function ( P  < 0.001). High FVIII/PC ratio values were significantly associated with higher postoperative morbidity, prolonged ICU and hospital stay and less survival ( P  < 0.05). High FVIII/PC ratio on postoperative day 2 was found to be predictor of posthepatectomy liver failure (PHLF; area under the ROC curve = 0.8129). Early postoperative high FVIII/PC ratio values are associated with low liver function, PHLF and poorer outcomes in patients undergoing major hepatic resection.

Volume-Assisted Estimation of Remnant Liver Function Based on Gd-EOB-DTPA Enhanced MR Relaxometry: A Prospective Observational Trial

In the context of liver surgery, predicting postoperative liver dysfunction is essential. This study explored the potential of preoperative liver function assessment by MRI for predicting postoperative liver dysfunction and compared these results with the established indocyanine green (ICG) clearance test. This prospective study included patients undergoing liver resection with preoperative MRI planning. Liver function was quantified using T1 relaxometry and correlated with established liver function scores. The analysis revealed an improved model for predicting postoperative liver dysfunction, exhibiting an accuracy (ACC) of 0.79, surpassing the 0.70 of the preoperative ICG test, alongside a higher area under the curve (0.75). Notably, the proposed model also successfully predicted all cases of liver failure and showed potential in predicting liver synthesis dysfunction (ACC 0.78). This model showed promise in patient survival rates with a Hazard ratio of 0.87, underscoring its potential as a valuable tool for preoperative evaluation. The findings imply that MRI-based assessment of liver function can provide significant benefits in the early identification and management of patients at risk for postoperative liver dysfunction.

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.

Diagnostic Accuracy of Indocyanine Green Clearance Test for Different Stages of Liver Fibrosis and Cirrhosis

(1) Background: This study aimed to correlate the indocyanine green clearance (ICG) test with histopathological grades of liver fibrosis and liver cirrhosis to assess its diagnostic accuracy in differentiating normal liver parenchyma from liver fibrosis and liver cirrhosis. (2) Methods: A total of 82 patients who received a histopathological liver examination, imaging, and ICG test within three months were included in this retrospective study. The histopathological level of fibrosis was graded using the Ishak scoring system, and the patients were divided into five categories: no liver fibrosis (NLF), mild liver fibrosis (MLF), advanced liver fibrosis (ALF), severe liver fibrosis (SLF), and liver cirrhosis (LC). The non-parametric Kruskal-Wallis test with post hoc pairwise comparison utilizing Mann-Whitney U tests and Bonferroni adjustment was used to analyze differences in the ICG test results between the patient groups. Cross correlation between the individual fibrosis/cirrhosis stages and the score of the ICG test was performed, and the sensitivity, specificity, and positive and negative predictive values were calculated for each model predicting liver fibrosis/cirrhosis. (3) Results: A significant difference (p ≤ 0.001) between stages of NLF, LF, and LC was found for the ICG parameters (ICG plasma disappearance rate (ICG-PDR) and ICG retention percentage at 15 min (ICG-R15)). The post hoc analysis revealed that NLF significantly differed from SLF (ICG-PDR: p = 0.001; ICG-R15: p = 0.001) and LC (ICG-PDR: p = 0.001; ICG-R15: p = 0.001). ALF also significantly differed from SLF (ICG-PDR: p = 0.033; ICG-R15: p = 0.034) and LC (ICG-PDR: p = 0.014; ICG-R15: p = 0.014). The sensitivity for detection of an initial stage of liver fibrosis compared to no liver fibrosis (Ishak  ≥  1) was 0.40; the corresponding specificity was 0.80. The differentiation of advanced liver fibrosis or cirrhosis (Ishak ≥ 4) compared to other stages of liver fibrosis was 0.75, with a specificity of 0.81. (4) Conclusions: This study shows that the ICG test, as a non-invasive diagnostic test, is able to differentiate patients with no liver fibrosis from patients with advanced liver fibrosis and liver cirrhosis. The ICG test seems to be helpful in monitoring patients with liver fibrosis regarding compensation levels, thus potentially enabling physicians to both detect progression from compensated liver fibrosis to advanced liver fibrosis and cirrhosis and to initiate antifibrotic treatment at an earlier stage.

Relative enhancement index can be used to quantify liver function in cirrhotic patients that undergo gadoxetic acid-enhanced MRI

OBJECTIVES

To evaluate MRI with gadoxetic acid to quantify liver function in cirrhotic patients using the relative enhancement index (REI) compared with Child-Pugh score (CPS), MELD score, and indocyanine green plasma disappearance rate (ICG-PDR) and to establish cutoffs for REI to stratify cirrhotic patients into good and poor liver function groups.

METHODS

We prospectively evaluated 60 cirrhotic patients and calculated CPS, MELD score, ICG-PDR, and REI for each patient. Spearman's correlation coefficient was used to assess correlation between REI, CPS, MELD, and ICG-PDR. Good and poor liver function groups were created by k-means clustering algorithm using CPS, MELD, and ICG-PDR. ROC curve analysis was performed and optimal cutoff was identified for group differentiation.

RESULTS

Good correlations were found between REI and other liver function biomarkers: REI and CPS (rho =  - 0.816; p < 0.001); REI and MELD score (rho =  - 0.755; p < 0.001); REI and ICG-PDR (rho = 0.745; p < 0.001)]. REI correlation was stronger for patients with Child-Pugh A (rho = 0.642, p = 0.002) and B (rho = 0.798, p < 0.001) than for those with Child-Pugh C (rho = 0.336, p = 0.148). REI is significantly lower in patients with poor liver function (p < 0.001). ROC curve showed an AUC 0.94 to discriminate patients with poor liver function (REI cutoff < 100; 100% sensitivity; 76% specificity).

CONCLUSIONS

REI is a valuable non-invasive index for liver function quantification that has good correlations with other liver function biomarkers. REI can be easily calculated and can be used to estimate liver function in clinical practice in the routine evaluation of cirrhotic patients that undergo MR imaging with gadoxetic acid contrast.

KEY POINTS

• REI is a valuable non-invasive index for liver function quantification that has good correlations with other liver function biomarkers. • REI can be easily calculated in the routine evaluation of cirrhotic patients that undergo gadoxetic acid-enhanced MRI. • The REI enables stratification of cirrhotic patients into good and poor liver function groups and can be used as additional information, together with morphological and focal liver lesion evaluation.

[Indocyanine green in liver transplantation]

The purpose of this study was to evaluate the first own experience of using indocyanine green (ICG) in liver transplantation compared to literature data and to determine its potential for clinical practice. Liver transplantation is an effective option for patients with end-stage disease, but this procedure is associated with many problems such as graft rejection, graft dysfunction, surgical risk and postoperative management. Modern methods for assessing graft function have their limitations, so a more efficient method is needed. According to this review, ICG fluorescence is valuable for effective intraoperative blood flow control, assessment of graft function, intraoperative and postoperative monitoring of clinical status. ICG fluorescence can also predict clinical status of patients at all stages of liver transplantation. Routine ICG fluorescence method is advisable in liver transplantation to improve outcomes and optimize treatment process.

Preoperative indocyanine green (ICG) clearance test: Can we really trust it to predict post hepatectomy liver failure? A systematic review of the literature and meta-analysis of diagnostic test accuracy

INTRODUCTION

Post hepatectomy liver failure (PHFL) still represents a potentially fatal complication after major liver resection. Indocyanine green (ICG) clearance test represents one of the most widely adopted examinations in the preoperative workup. Despite a copious body of evidence which has been published on this topic, the role of ICG in predicting PHLF is still a matter of debate.

METHODS

A systematic review of the literature was conducted according to PRISMA-DTA guidelines. The primary outcome was the assessment of diagnostic performance of ICG in predicting PHLF. The secondary outcome was the mean ICG_R15 and ICG_PDR in patients experiencing PHLF.

RESULTS

Seventeen studies, for a total of 4852 patients, were deemed eligible. Sensitivity ranged from 25% to 83%; Specificity ranged from 66.1% to 93.8%. ICG clearance test pooled AUC was 0.673 (95% CI: 0.632-0.713). The weighted mean ICG_R15 was 11 (95%CI: 8.3-13.7). The weighted mean ICG_PDR was 16.5 (95%CI: 13.3-19.8). High risk of bias was detected in all examined domains.

CONCLUSIONS

Preoperative ICG clearance test alone may not represent a reliable method to predict post hepatectomy liver failure. Its diagnostic significance should be framed within multiparametric models involving clinical and imaging features.

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.

Efficacy of lenvatinib combined with sequential transarterial chemoembolization for primary hepatocellular carcinoma and the effects on serum basic fibroblast growth factor and vascular endothelial growth factor

Objective: The aim of this research was to investigate the therapeutic efficacy of lenvatinib combined with sequential transarterial chemoembolization (TACE) on primary hepatocellular carcinoma (HCC) and the effects on serum basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF).

Method: A total of 104 patients with primary HCC, admitted to People’s Hospital of Leshan from April 2018 to January 2021, were selected as the study subjects and were divided into the TACE-LEN group (n = 53) who were treated with lenvatinib combined with sequential TACE and the TACE group (n = 51) who were treated with TACE alone, according to the appropriate treatment modalities. The clinical efficacy 8 weeks after treatment; the serum levels of total bilirubin, conjugated bilirubin, and alanine aminotransferase (ALT); the prothrombin time (PT); the indocyanine green retention rate at 15 min (ICGR15); and the serum bFGF and VEGF levels before treatment and at 8 weeks after treatment were compared between the two groups. The incidence of adverse events and the survival rates at 18 months were also recorded for both groups. COX regression analysis was used to analyze the risk factors affecting the survival of patients.

Results: Eight weeks after treatment, the objective response rate was higher in the TACE-LEN group than in the TACE group (77.36% vs. 56.36%, p < 0.05), but there were no statistically significant differences in the bilirubin and ALT levels, the PT, and the ICGR15 between the two groups (p > 0.05). The serum bFGF and VEGF levels post-therapeutic were lower in the TACE-LEN group than in the TACE group (p < 0.05). The differences in the incidence of postoperative adverse events and the survival rate within 6 months were not statistically significant between the two groups (p > 0.05). In addition, the survival rates within 12 and 18 months after treatment were higher in the TACE-LEN group than in the TACE group than in the TACE group (81.1% vs. 64.7%, 69.8% vs. 49.1%, p < 0.05). ICG-R15 and treatment regimen are risk factors for survival.

Conclusion: The worse the liver reserve is, the worse the prognosis is. The combination of TACE and lenvatinib showed better efficacy and longer survival than TACE monotherapy for HCC patients and reduced the levels of bFGF and VEGF.

Prevalence of fatty liver disease after liver transplantation and risk factors for recipients and donors

INTRODUCTION AND OBJECTIVES

Fatty liver disease (FLD) may develop in liver transplant recipients. We investigated the recipient and donor risk factors for FLD development after liver transplantation (LT).

METHODS

A total of 108 liver transplant recipients (54 men [50.0%]; median age, 52 [20-68] years) treated from 2011-2020 was enrolled. Three recipients died at < 3 months as a result of infection or blood flow impairment, and were excluded from the long-term FLD study. On evaluation of 88 prospective living donors, fatty liver was observed in 21. The prevalence and risk factors for FLD and survival were evaluated.

RESULTS

After LT, 28 of 105 recipients (26.7%) developed FLD. FLD was more common in patients with a high body mass index (BMI) and dyslipidemia (both p < 0.01), primary nonalcoholic steatohepatitis (p = 0.02), after living-donor LT (p = 0.03) and everolimus (EVL) use (p = 0.08). Factors predictive of FLD included EVL use and a high BMI (hazard ratios = 3.00 and 1.34; p = 0.05 and p < 0.01, respectively). Sixteen donors lost 6.5 kg (range: 2.0-16.0 kg) of body weight prior to LT. However, there were no cases of primary non-function, which did not affect the FLD prevalence. Development of FLD did not have a negative impact on LT outcome; the 5-year survival rate was 92.6%.

CONCLUSIONS

Recipient factors were more important than donor factors for FLD onset after LT.

Prediction of Survival After Partial Hepatectomy Using a Physiologically Based Pharmacokinetic Model of Indocyanine Green Liver Function Tests

The evaluation of hepatic function and functional capacity of the liver are essential tasks in hepatology as well as in hepatobiliary surgery. Indocyanine green (ICG) is a widely applied test compound that is used in clinical routine to evaluate hepatic function. Important questions for the functional evaluation with ICG in the context of hepatectomy are how liver disease such as cirrhosis alters ICG elimination, and if postoperative survival can be predicted from preoperative ICG measurements. Within this work a physiologically based pharmacokinetic (PBPK) model of ICG was developed and applied to the prediction of the effects of a liver resection under various degrees of cirrhosis. For the parametrization of the computational model and validation of model predictions a database of ICG pharmacokinetic data was established. The model was applied (i) to study the effect of liver cirrhosis and liver resection on ICG pharmacokinetics; and (ii) to evaluate the model-based prediction of postoperative ICG-R15 (retention ratio 15 min after administration) as a measure for postoperative outcome. Key results are the accurate prediction of changes in ICG pharmacokinetics caused by liver cirrhosis and postoperative changes of ICG-elimination after liver resection, as validated with a wide range of data sets. Based on the PBPK model, individual survival after liver resection could be classified, demonstrating its potential value as a clinical tool.

Hepatectomy-Induced Alterations in Hepatic Perfusion and Function - Toward Multi-Scale Computational Modeling for a Better Prediction of Post-hepatectomy Liver Function

Liver resection causes marked perfusion alterations in the liver remnant both on the organ scale (vascular anatomy) and on the microscale (sinusoidal blood flow on tissue level). These changes in perfusion affect hepatic functions via direct alterations in blood supply and drainage, followed by indirect changes of biomechanical tissue properties and cellular function. Changes in blood flow impose compression, tension and shear forces on the liver tissue. These forces are perceived by mechanosensors on parenchymal and non-parenchymal cells of the liver and regulate cell-cell and cell-matrix interactions as well as cellular signaling and metabolism. These interactions are key players in tissue growth and remodeling, a prerequisite to restore tissue function after PHx. Their dysregulation is associated with metabolic impairment of the liver eventually leading to liver failure, a serious post-hepatectomy complication with high morbidity and mortality. Though certain links are known, the overall functional change after liver surgery is not understood due to complex feedback loops, non-linearities, spatial heterogeneities and different time-scales of events. Computational modeling is a unique approach to gain a better understanding of complex biomedical systems. This approach allows (i) integration of heterogeneous data and knowledge on multiple scales into a consistent view of how perfusion is related to hepatic function; (ii) testing and generating hypotheses based on predictive models, which must be validated experimentally and clinically. In the long term, computational modeling will (iii) support surgical planning by predicting surgery-induced perfusion perturbations and their functional (metabolic) consequences; and thereby (iv) allow minimizing surgical risks for the individual patient. Here, we review the alterations of hepatic perfusion, biomechanical properties and function associated with hepatectomy. Specifically, we provide an overview over the clinical problem, preoperative diagnostics, functional imaging approaches, experimental approaches in animal models, mechanoperception in the liver and impact on cellular metabolism, omics approaches with a focus on transcriptomics, data integration and uncertainty analysis, and computational modeling on multiple scales. Finally, we provide a perspective on how multi-scale computational models, which couple perfusion changes to hepatic function, could become part of clinical workflows to predict and optimize patient outcome after complex liver surgery.

Surgical management of intrahepatic cholangiocarcinoma

INTRODUCTION

Intrahepatic cholangiocarcinoma (ICC) incidence continues to rise worldwide, and overall survival remains poor. Complete surgical resection remains the only opportunity for cure in patients with ICC yet only one-third of patients present with resectable disease.

AREAS COVERED

While the low incidence rate of ICC hinders accrual of patients to large, randomized control trials, larger database and long-term institutional studies provide evidence to guide surgical management of ICC. These studies demonstrate feasibility, safety, and efficacy of aggressive surgical management in appropriately selected patients with ICC. Recent advances in the management of ICC, with a focus on surgical considerations, are reviewed.

EXPERT OPINION

Historically, little progress has been made in the management of ICC with stagnant mortality rates and poor long-term outcomes. However, regionalization of care to centers with experienced multidisciplinary teams, advances in minimally invasive surgical techniques, discovery and development of targeted and immunotherapy agents, and combination locoregional and systemic therapies offer signs of progress in the management of ICC.

Epigenetic-sensitive challenges of cardiohepatic interactions: clinical and therapeutic implications in heart failure patients

Heart failure and liver dysfunction can coexist owing to complex cardiohepatic interactions including the development of hypoxic hepatitis and congestive hepatopathy in patients with heart failure as well as 'cirrhotic cardiomyopathy' in advanced liver disease and following liver transplantation. The involvement of liver dysfunction in patients with heart failure reflects crucial systemic hemodynamic modifications occurring during the evolution of this syndrome. The arterial hypoperfusion and downstream hypoxia can lead to hypoxic hepatitis in acute heart failure patients whereas passive congestion is correlated with congestive hepatopathy occurring in patients with chronic heart failure. Nowadays, liquid biopsy strategies measuring liver function are well established in evaluating the prognosis of patients with heart failure. Large randomized clinical trials confirmed that gamma-glutamyltransferase, bilirubin, lactate deihydrogenase, and transaminases are useful prognostic biomarkers in patients with heart failure after transplantation. Deeper knowledge about the pathogenic mechanisms underlying cardiohepatic interactions would be useful to improve diagnosis, prognosis, and treatments of these comorbid patients. Epigenetic-sensitive modifications are heritable changes to gene expression without involving DNA sequence, comprising DNA methylation, histone modifications, and noncoding RNAs which seem to be relevant in the pathogenesis of heart failure and liver diseases when considered in a separate way. The goal of our review is to highlight the pertinence of detecting epigenetic modifications during the complex cardiohepatic interactions in clinical setting. Moreover, we propose a clinical research program which may be useful to identify epigenetic-sensitive biomarkers of cardiohepatic interactions and advance personalized therapy in these comorbid patients.

Predicting Post-Hepatectomy Liver Failure Using Intra-Operative Measurement of Indocyanine Green Clearance in Anatomical Hepatectomy

BACKGROUND

Prediction of post-hepatectomy liver failure (PHLF) based on remnant liver function reserve is important for successful hepatectomy. The aim of this study was to investigate whether intraoperative indocyanine green (ICG) clearance in a future remnant liver was a predictor of PHLF.

METHODS

This prospective study enrolled 31 consecutive patients who underwent anatomical hepatectomy between June 2016 and August 2019. Intraoperative ICG plasma disappearance rate (ICG-PDR) and ICG retention rate at 15 min (ICG-R15) were measured after clamping the selective hepatic inflow to the liver to be resected. The discriminative performance of the ICG-associated variables for the prediction of PHLF grade B/C was evaluated by receiver operator curve (ROC) analysis.

RESULTS

Of the operations performed, 87.1% were major hepatectomy. PHLF Grade B/C was observed in eight patients (25.8%) with no mortality. The concordance indices of intraoperative ICG-PDR and ICG-PDR for predicting PHLF were 0.834 (95% CI, 0.69-0.98) and 0.834 (95% CI, 0.69-0.98), respectively. A subgroup analysis of patients with preoperative biliary drainage (BD) (n = 17) showed that the concordance indices of intraoperative ICG-PDR increased to 0.923 (95% CI, 0.79-1.00).

CONCLUSIONS

Intraoperative ICG clearance in the remnant liver was a promising predictor for PHLF in patients undergoing anatomical hepatectomy, especially in patients with BD.

Hepatocellular uptake index obtained with gadoxetate disodium-enhanced magnetic resonance imaging in the assessment future liver remnant function after major hepatectomy for biliary malignancy

Background

Functional assessment of the future liver remnant (FLR) after major hepatectomy is essential but often difficult in patients with biliary malignancy, owing to obstructive jaundice and portal vein embolization. This study evaluated whether a novel index using gadoxetate disodium-enhanced MRI (EOB-MRI) could predict posthepatectomy liver failure (PHLF) after major hepatectomy for biliary malignancy.

Methods

The remnant hepatocellular uptake index (rHUI) was calculated in patients undergoing EOB-MRI before major hepatectomy for biliary malignancy. Receiver operating characteristic (ROC) curve analyses were used to evaluate the accuracy of rHUI for predicting PHLF grade B or C, according to International Study Group of Liver Surgery criteria. Multivariable logistic regression analyses comprised stepwise selection of parameters, including rHUI and other conventional indices.

Results

This study included 67 patients. The rHUI accurately predicted PHLF (area under the curve (AUC) 0.896). A cut-off value for rHUI of less than 0.410 predicted all patients who developed grade B or C PHLF. In multivariable analysis, only rHUI was an independent risk factor for grade B or C PHLF (odds ratio 2.0 × 10³, 95 per cent c.i. 19.6 to 3.8 × 10⁷; P < 0.001). In patients who underwent preoperative portal vein embolization, rHUI accurately predicted PHLF (AUC 0.885), whereas other conventional indices, such as the plasma disappearance rate of indocyanine green of the FLR and FLR volume, did not.

Conclusion

The rHUI is potentially a useful predictor of PHLF after major hepatectomy for biliary malignancy.

Is portal vein embolization safe and effective for patients with impaired liver function?

BACKGROUND AND OBJECTIVES

Portal vein embolization (PVE) is a safe and effective procedure used to increase the safety of extensive hepatectomy for selected patients. However, it is unknown whether PVE is safe for patients with impaired liver functional reserve.

METHODS

Patients who underwent PVE from April 2007 to September 2016 in our hospital were retrospectively assessed. According to indocyanine green retention rate at 15 min (ICG-R15), we divided patients into Group A (≤10%), Group B (10%-20%), and Group C (>20%). We described and compared the treatment course and the outcome among the three groups.

RESULTS

A total of 106 patients were assessed and divided into groups A (n = 46), B (n = 49), and C (n = 11). The morbidity and mortality after PVE showed no significant differences among the three groups (A:B:C = 37%:53%:64%, p = .16; A:B:C = 0%:0%:0%, p = 1.00, respectively). The morbidity and mortality after successive hepatectomy also showed no significant differences among the three groups (A:B:C = 55%:71%:78%, p = .19; A:B:C = 0%:2%:0%, p = 1.00, respectively).

CONCLUSION

A patient with impaired liver functional reserve (ICG-R15 > 20%) can be a candidate for PVE and successive hepatectomy, as safely as a patient with normal and slightly impaired liver functional reserve (ICG-R15 ≤ 20%).

Preoperative ICG Test to Predict Posthepatectomy Liver Failure and Postoperative Outcomes in Hilar Cholangiocarcinoma

Preoperative evaluation of hepatic functional reserve in patients with hilar cholangiocarcinoma (hCCA) has vital clinical significance for prevention of posthepatectomy liver failure (PHLF) and mortality. The aim of the present study was to evaluate the clinical significance of the indocyanine green retention rate at 15 minutes (ICG R15) and related factors of postoperative outcomes in patients with hCCA. 147 patients who scheduled for hCCA resection underwent a preoperative ICG test between May 2015 and May 2020 and were prospectively analyzed. Single-factor analysis was used to evaluate the risk factors for PHLF and postoperative outcomes in hCCA. After univariate analysis, significant differences in ICG R15 were found between the PHLF group and the liver function recovered well (LFRW) group (P ≤ 0.05). In terms of postoperative complications, ICG R15 was also a risk factor for moderate-to-severe postoperative complications. Preoperative ICG R15 was significantly associated with PHLF and moderate-to-severe postoperative complications. ICG R15 may become an ideal clinical indicator for the evaluation of liver function reserve before hCCA and can better predict the postoperative complications.

Combined APRI/ALBI score to predict mortality after hepatic resection

Background

Aspartate aminotransferase/platelet ratio index (APRI) and albumin–bilirubin grade (ALBI) are validated prognostic indices implicated as predictors of postoperative liver dysfunction after hepatic resection. The aim of this study was to evaluate the relevance of the combined APRI/ALBI score for postoperative clinically meaningful outcomes.

Methods

Patients undergoing hepatectomy were included from the American College of Surgeons National Surgical Quality Improvement Program database. The association between APRI/ALBI score and postoperative grade C liver dysfunction, liver dysfunction-associated and overall 30-day mortality was assessed.

Results

A total of 12 055 patients undergoing hepatic resection from 2014 to 2017 with preoperative blood values and detailed 30-day postoperative outcomes were included (exploration cohort: January 2014 to December 2016; validation cohort: 2017). In the exploration cohort (8538 patients), the combination of both scores (APRI/ALBI) was significantly associated with postoperative grade C liver dysfunction, 30-day mortality, and liver dysfunction-associated 30-day mortality, and was superior to either score alone. The association with postoperative 30-day mortality was confirmed in multivariable analysis. A predictive model was generated using the exploration cohort. The predicted incidence of events closely followed the observed incidence in the validation cohort (3517 patients). Subgroup analyses of tumour types were used to generate disease-specific risk models to assess risk in different clinical scenarios. These findings informed development of a smartphone application (https://tellaprialbi.37binary.com).

Conclusion

The predictive potential of the combined APRI/ALBI score for clinically relevant outcomes such as mortality was demonstrated. An evidence-based smartphone application will allow clinical translation and facilitation of risk assessment before hepatic resection using routine laboratory parameters.

Perioperative assessment of indocyanine green elimination rate accurately predicts postoperative liver failure in patients undergoing hepatectomy

BACKGROUND

This study aimed to evaluate the usefulness of perioperative indocyanine green elimination rate (ICG-K) as a predictive factor of posthepatectomy liver failure (PHLF).

METHODS

This study enrolled 193 patients who underwent hepatectomy between 2013 and 2019. We analyzed the relationship between estimated ICG-K (ICG-Krem) calculated by the preoperative ICG-K and the residual liver volume ratio, ICG-K at days 1 and 7 after hepatectomy (ICG-Kpod1, ICG-Kpod7), and grade B or C PHLF.

RESULTS

Grade B and C PHLF were observed in eight and two patients, respectively. ICG-Krem and ICG-Kpod1 were highly correlated (correlation coefficient [CC] 0.715), and ICG-Krem and ICG-Kpod7 were moderately correlated (CC 0.653). Receiver-operating characteristic curve analyses indicated that ICG-Krem and ICG-Kpod1 had moderate diagnostic value, while ICG-Kpod7 had high diagnostic value (area under the curve 0.703, 0.845 and 0.937, respectively). Multivariate analysis demonstrated that ICG-Kpod7 (relative risk [RR] 26.04, P = .012) and postoperative bile leakage (PBL) (RR 226.0, P < .001) were independent predictive factors for PHLF. PBL induced PHLF in seven patients, respectively.

CONCLUSIONS

ICG-Krem correlated well with postoperative ICG-K, having moderate accuracy as a predictor of PHLF. However, the clinical relevance of postoperatively measuring ICG-K is limited because PHLF is greatly affected by surgical and postoperative factors.

Laparoscopic Liver Surgery: What Are the Advantages in Patients with Cirrhosis and Portal Hypertension? Systematic Review and Meta-Analysis with Personal Experience

Background: Laparoscopic surgery is a choice of treatment for liver diseases; it can decrease postoperative morbidity and length of hospital stay (LOS). Hepatocellular carcinoma (HCC) in patients with cirrhosis and portal hypertension may benefit from minimally invasive liver resections (MILRs) instead of open liver resections (OLRs). Whether minimally invasive approaches are superior to conventional ones is still a matter of debate. We thus aimed to gather the available literature on this specific topic to achieve greater clarity. Materials and Methods: PubMed, EMBASE and Web of Sciences databases were assessed for studies comparing OLRs versus MILRs for HCC in cirrhotic patients up to February 2020. Data from our surgical experience from June 2010 to February 2020 were also included. Demographic characteristics, liver function, the presence of portal hypertension, tumor number, and tumor size and location were assessed; operative time, need for Pringle maneuver, estimated blood loss (EBL), major or minor hepatectomy performance, and conversion rate were evaluated for operative findings. Postoperative outcomes and liver-related complications, surgical site infection (SSI) rate, blood transfusion (BT) rate, need for reintervention, LOS, in-hospital or 30-day mortality, and radicality of resection were also considered. Meta-analysis was performed employing Review Manager 5.3 software. Results: One thousand three hundred twenty-one patients from 13 studies and our own series were considered in the meta-analysis. At preoperative settings, the OLR and MILR groups differed significantly only by tumor size (4.4 versus 3.0, P = .006). Laparoscopic procedures resulted significantly faster (120.32-330 minutes versus 146.8-342.75 minutes, P = .002) and with lower EBL than open ones (88-483 mL versus 200-580 mL, P < .00001), thus requiring less BTs (7.9% versus 13.2%, P = .02). In terms of overall morbidity, minimally invasive surgeries resulted significantly favorable (19.32% versus 38.04%, P < .00001), as well as for ascites (2.7% versus 12.9% P < .00001), postoperative liver failure (7.51% versus 13.61% P = .009), and SSI (1.8% versus 5.42%, P = .002). Accordingly, patients who had undergone MILRs had significantly shorter postoperative hospitalization than patients who underwent conventional open surgery (2.4-36 days versus 4.2-19 days P < .00001). Both groups did not differ in terms of mortality rate and radicality of resection (OLR 93.8% versus 96.1% laparoscopic liver resection, P = .12). Conclusions: Based on the available evidence in the literature, laparoscopic resections rather than open liver ones for HCC surgery in cirrhotic patients seem to reduce postoperative overall morbidity, liver-specific complications, and LOS. The lack of randomized studies on this topic precludes the possibility of achieving defining statements.

Portal Vein Embolization is Associated with Reduced Liver Failure and Mortality in High-Risk Resections for Perihilar Cholangiocarcinoma

BACKGROUND

Preoperative portal vein embolization (PVE) is frequently used to improve future liver remnant volume (FLRV) and to reduce the risk of liver failure after major liver resection.

OBJECTIVE

This paper aimed to assess postoperative outcomes after PVE and resection for suspected perihilar cholangiocarcinoma (PHC) in an international, multicentric cohort.

METHODS

Patients undergoing resection for suspected PHC across 20 centers worldwide, from the year 2000, were included. Liver failure, biliary leakage, and hemorrhage were classified according to the respective International Study Group of Liver Surgery criteria. Using propensity scoring, two equal cohorts were generated using matching parameters, i.e. age, sex, American Society of Anesthesiologists classification, jaundice, type of biliary drainage, baseline FLRV, resection type, and portal vein resection.

RESULTS

A total of 1667 patients were treated for suspected PHC during the study period. In 298 patients who underwent preoperative PVE, the overall incidence of liver failure and 90-day mortality was 27% and 18%, respectively, as opposed to 14% and 12%, respectively, in patients without PVE (p < 0.001 and p = 0.005). After propensity score matching, 98 patients were enrolled in each cohort, resulting in similar baseline and operative characteristics. Liver failure was lower in the PVE group (8% vs. 36%, p < 0.001), as was biliary leakage (10% vs. 35%, p < 0.01), intra-abdominal abscesses (19% vs. 34%, p = 0.01), and 90-day mortality (7% vs. 18%, p = 0.03).

CONCLUSION

PVE before major liver resection for PHC is associated with a lower incidence of liver failure, biliary leakage, abscess formation, and mortality. These results demonstrate the importance of PVE as an integral component in the surgical treatment of PHC.

Sarcopenia increases 1-year mortality after surgical resection of hepatocellular carcinoma

BACKGROUND

Liver resection is a well-recognized modality for hepatocellular carcinoma. Cirrhotic patients are more prone to adverse consequences after liver resection. This work assesses the prognostic significance of sarcopenic hepatocellular carcinoma cases for whom surgical resection was performed.

METHODS

The present prospective work included 52 cirrhotic cases. Computed tomography scans were used to determine the skeletal muscle index (SMI) at the plane of the third lumbar vertebra (L3). L3 SMI was used for the definition of sarcopenia. The primary outcome measure was the predictive value of sarcopenia for 1-year post-hepatectomy mortality.

RESULTS

Sarcopenia was diagnosed in 27 patients (51.9%). All patients had a Child-Turcotte-Pugh score A. At a 1-year follow-up, 20 cases died; that is the 1-year mortality rate was 38.5%. Sarcopenia was more commonly associated with older age and non-viral causes of cirrhosis. The risk of 1-year mortality is 7.6 times higher in sarcopenic patients with a risk ratio of 3.7 (95% confidence interval 1.4-9.6).

CONCLUSION

Sarcopenia diagnosed using L3 SMI is an independent prognostic factor for 1-year deaths in cases with hepatic malignancy with Child-Turcotte-Pugh score A undergoing surgical resection.

Value of contrast-enhanced ultrasound for preoperative assessment of liver reserve function in patients with liver tumors

This study aimed to investigate the value of contrast-enhanced ultrasound (CEUS) for preoperative assessment of liver reserve function in patients with liver tumors. The indocyanine green (ICG) clearance tests and CEUS examinations of 45 noncirrhotic patients with liver tumors were performed prior to liver resection. Parameters time to peak (TtoPk), arrival time (Atm) as well as perfusion parameters A, k and A x k were generated from time-intensity curve (TIC) of CEUS. The correlation analyses of the ICG clearance per unit time (ICGK) and the retention rate at 15 min (ICGR15) with TtoPk, Atm, A, k and A x k were performed, and the diagnostic ability as well as optimal cut-off values of TtoPk and Atm for differentiating patients with ICGR15>10% from ICGR15<10% were analyzed. There were significant correlations of ICGK with TtoPk and Atm, and the correlation coefficients were 0.363 (p = 0.014) and -0.482 (p = 0.001), respectively. Significant correlations of ICGR15 with TtoPk and Atm were revealed, and the correlation coefficients were -0.416 (p = 0.004) and 0.303 (p = 0.043), respectively. No correlation of ICGK or ICGR15 with A, k and A x k was found in this study. There were significant differences in TtoPk and Atm between patients with ICGR15>10% and ICGR15<10% (p = 0.028 and p = 0.026, respectively). TtoPk and Atm both had good diagnostic abilities in diagnosing patients with ICGR15>10% verusus ICGR15<10% (AUROC = 0.711 and 0.721, respectively). For ICGR15>10% vs ICGR15, the optimal cut-off values of TtoPk and Atm were 13.307 s and 11.007 s, respectively, while the sensitivity and specificity were 75.0% and 72.7%, 60.6% and 75.0%, respectively. This study revealed that CEUS has the potential to be a new method to evaluate the liver reserve function of patients. With the optimal cut-off values of TtoPk and Atm, qualitative assessment of patients with ICGR15>10% could be more easily achieved by CEUS with good diagnostic abilities.

The value of indocyanine green clearance assessment to predict postoperative liver dysfunction in patients undergoing liver resection

Postoperative liver dysfunction remains a major concern following hepatic resection. In order to identify patients who are at risk of developing liver dysfunction, indocyanine green (ICG) clearance has been proposed to predict postoperative liver function. All patients who underwent liver resection at the Medical University Vienna, Austria between 2006 and 2015 with preoperative ICG clearance testing (PDR, R15) were analyzed in this study. Postoperative liver dysfunction was analyzed as defined by the International Study Group of Liver Surgery. Overall, 698 patients (male: 394 (56.4%); female: 304 (43.6%)) with a mean age of 61.3 years (SD: 12.9) were included in this study, including 313 minor liver resections (44.8%) and 385 major liver resections (55.2%). One hundred and seven patients developed postoperative liver dysfunction after liver resection (15.3%). Factors associated with liver dysfunction were: male sex (p = 0.043), major liver resection (p < 0.0001), and preoperative ICG clearance (PDR (p = 0.002) and R15 (p < 0.0001)). Notably ICG clearance was significantly associated with liver dysfunction in minor and major liver resections respectively and remained a predictor upon multivariable analysis. An optimal cut-off for preoperative ICG clearance to accurately predict liver dysfunction was PDR < 19.5%/min and R15 > 5.6%. To the best of our knowledge, this is the largest study analyzing the predictive value of preoperative ICG clearance assessment in patients undergoing liver resection. ICG clearance is useful to identify patients at risk of postoperative liver dysfunction.

Predicting Postoperative Liver Dysfunction Based on Blood-Derived MicroRNA Signatures

There is an urgent need for an easily assessable preoperative test to predict postoperative liver function recovery and thereby determine the optimal time point of liver resection, specifically as current markers are often expensive, time consuming, and invasive. Emerging evidence suggests that microRNA (miRNA) signatures represent potent diagnostic, prognostic, and treatment-response biomarkers for several diseases. Using next-generation sequencing as an unbiased systematic approach, 554 miRNAs were detected in preoperative plasma of 21 patients suffering from postoperative liver dysfunction (LD) after liver resection and 27 matched controls. Subsequently, we identified a miRNA signature-consisting of miRNAs 151a-5p, 192-5p, and 122-5p-that highly correlated with patients developing postoperative LD after liver resection. The predictive potential for postoperative LD was subsequently confirmed using real-time PCR in an independent validation cohort of 98 patients. Ultimately, a regression model of the two miRNA ratios 151a-5p to 192-5p and 122-5p to 151a-5p was found to reliably predict postoperative LD, severe morbidity, prolonged intensive care unit and hospital stays, and even mortality before an operation with a remarkable accuracy, thereby outperforming established markers of postoperative LD. Ultimately, we documented that miRNA ratios closely followed liver function recovery after partial hepatectomy. Conclusion: Our data demonstrate the clinical utility of an miRNA-based biomarker to support the selection of patients undergoing partial hepatectomy. The dynamical changes during liver function recovery indicate a possible role in individualized patient treatment. Thereby, our data might help to tailor surgical strategies to the specific risk profile of patients.

Greater survival despite increased complication rates following lung transplant for alpha-1-antitrypsin deficiency compared to chronic obstructive pulmonary disease

Background

Alpha-1-antitrypsin (A1AT) deficiency (A1ATD) is characterized by accelerated degradation of lung function. We examined our experience with lung transplantation for chronic obstructive pulmonary disease (COPD) with and without A1ATD to compare survival and rates of postoperative surgical complications.

Methods

Patients with A1ATD and non-A1ATD COPD undergoing lung transplantation from 1988-2015 at our institution were analyzed. Complications were categorized into non-gastroenteritis gastrointestinal (GI), wound, airway, and reoperation for bleeding. Overall and complication-free survival were evaluated using Kaplan-Meier curves and Cox proportional hazards models.

Results

Three hundred and eighty-five patients underwent lung transplant for COPD (98 A1ATD). For A1ATD, 56.1% underwent single lung transplantation (80.6% for COPD). Early overall and complication-free survival was worse for A1ATD, but this trend reversed at longer follow up. Unadjusted estimated survival showed advantage for COPD at 90 days and 1 year, which attenuated by 5 years and reversed at 10 years (P<0.001). On adjusted analysis, A1ATD was associated with a trend toward lower complication-free survival at 90 days and 1 year, due partly to increased rates of post-transplant GI pathology, particularly in the era of the lung allocation score (LAS).

Conclusions

A1ATD lung recipients had worse short-term complication-free survival but improved long-term survival compared to COPD patients. A1ATD was associated with greater risk of new GI pathology after transplant. Close monitoring of A1ATD patients with timely evaluation of GI complaints after transplant is warranted.

Non-invasive Evaluation of NAFLD with Indocyanine Green Clearance Test: a Preliminary Study in Morbidly Obese Patients Undergoing Bariatric Surgery

BACKGROUND

Overweight and obesity dramatically increased in the last years. Hepatic complication of obesity, integrated in the term of non-alcoholic fatty liver disease (NAFLD), is a spectrum of abnormality ranging from steatosis to non-alcoholic steatohepatitis (NASH), potentially leading to cirrhosis. Liver biopsy remains the gold standard to evaluate the stage of NAFLD; however, the procedure is invasive. The indocyanine green (ICG) clearance test is performed since years to assess hepatic function before partial hepatectomy, or after liver transplantation. This study was designed to detect liver complications with the ICG clearance test in a population of obese patients scheduled for bariatric surgery.

METHODS

In a prospective cohort study, morbidly obese individuals receiving bariatric surgery with scheduled hepatic biopsies were investigated. Liver function was determined by the ICG test preoperatively, and blood samples were collected. Liver biopsy specimens were obtained for each patient and classified according to the NAFLD activity score (NAS) by a single pathologist that was blinded to the results of the ICG test.

RESULTS

Twenty-six patients were included (7 male and 19 female). The mean age of participants was 45.8 years; the mean body mass index was 41.4 kg/m². According to the NAS, 6 (23.1%) patients revealed manifest NASH, and 5 patients were considered borderline (19.2%). A closed correlation was observed between the ICG clearance test and hepatic steatosis (r = 0.43, p = 0.03), NAS (r = 0.44, p = 0.025), and fibrosis (r = 0.49, p = 0.01).

CONCLUSIONS

In obese patients, non-invasive evaluation of liver function with the indocyanine green clearance test correlated with histological features of NAFLD. This may detect non-invasively hepatopathy in obese population and could motive biopsy.

Post-hepatectomy liver failure after major hepatic surgery: not only size matters

Objectives

To compare the value of functional future liver remnant (functFLR) to established clinical and imaging variables in prediction of post-hepatectomy liver failure (PHLF) after major liver resection.

Methods

This retrospective, cross-sectional study included 62 patients, who underwent gadoxetic acid enhanced MRI and MDCT within 10 weeks prior to resection of ≥ 4 liver segments. Future liver remnant (FLR) was measured in MDCT using semi-automatic software. Relative liver enhancement for each FLR segment was calculated as the ratio of signal intensity of parenchyma before and 20 min after i.v. administration of gadoxetic acid and given as mean (remnantRLE). Established variables included indocyanine green clearance, FLR, proportion of FLR, weight-adapted FLR and remnantRLE. functFLR was calculated as FLR multiplied by remnantRLE and divided by patient’s weight. The association of measured variables and PHLF was tested with univariate and multivariate logistic regression analysis and receiver operator characteristics (ROC) curves compared with the DeLong method.

Results

Sixteen patients (25.8%) experienced PHLF. Univariate logistic regression identified FLR (p = 0.015), proportion of FLR (p = 0.004), weight-adapted FLR (p = 0.003), remnantRLE (p = 0.002) and functFLR (p = 0.002) to be significantly related to the probability of PHLF. In multivariate logistic regression analysis, a decreased functFLR was independently associated with the probability of PHLF (0.561; p = 0.002). Comparing ROC curves, functFLR showed a significantly higher area under the curve (0.904; p < 0.001) than established variables.

Conclusions

functFLR seems to be superior to established variables in prediction of PHLF after major liver resection.

Key Points

• functFLR is a parameter combining volumetric and functional imaging information, derived from MDCT and gadoxetic acid enhanced MRI.

• In comparison to other established methods, functFLR is superior in prediction of post-hepatectomy liver failure.

• functFLR could help to improve patient selection prior major hepatic surgery.

ICG Clearance Test and 99mTc-GSA SPECT/CT Fusion Images

Preoperative estimation of future remnant liver function is critical for major hepatic surgery to avoid postoperative morbidity and mortality. Among several liver function tests, the indocyanine green (ICG) clearance test is still the most popular dynamic method. The usefulness of ICG clearance test parameters, such as ICGR15, KICG, or PDRICG, has been reported by many investigators. The transcutaneous non-invasive pulse dye densitometry system has made the ICG clearance test more convenient and attractive, even in Western countries. The concept of future remnant KICG (rem KICG), which combines the functional aspect and the volumetric factor of the future remnant liver, seems ideal for determining the maximum extent of major hepatic resection that will not cause postoperative liver failure. For damaged livers with functional heterogeneity among the hepatic segments, fusion images combining technetium-99m-diethylenetriaminepentaacetic acid-galactosyl human serum albumin single photon emission computed tomography (99mTc-GSA SPECT) and X-ray CT are helpful to precisely estimate the functional reserve of the future remnant liver. Another technique for image-based liver function estimation, gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid(Gd-EOB)-enhanced magnetic resonance imaging, may be an ideal candidate for the preoperative determination of future remnant liver function. Using these methods effectively, morbidity and mortality after major hepatic resection could be reduced.

Assessment of liver perfusion and function by indocyanine green in the perioperative setting and in critically ill patients

Indocyanine green (ICG) is a water-soluble dye that is bound to plasma proteins when administered intravenously and nearly completely eliminated from the blood by the liver. ICG elimination depends on hepatic blood flow, hepatocellular function and biliary excretion. ICG elimination is considered as a useful dynamic test describing liver function and perfusion in the perioperative setting, i.e., in liver surgery and transplantation, as well as in critically ill patients. ICG plasma disappearance rate (ICG-PDR) which can be measured today by transcutaneous systems at the bedside is a valuable method for dynamic assessment of liver function and perfusion, and is regarded as a valuable prognostic tool in predicting survival of critically ill patients, presenting with sepsis, ARDS or acute liver failure.

Is there a standard for surgical therapy of hepatocellular carcinoma in healthy and cirrhotic liver? A comparison of eight guidelines

Background and aims

Liver resection (LR) and transplantation are the most reliable treatments for hepatocellular carcinoma (HCC). Aim was to compare different guidelines regarding indication for resection and transplantation because of HCC with and without underlying cirrhosis.

Methods

We compared the following guidelines published after 1 January 2010: American (American Association for the Study of Liver Diseases (AASLD)), Spanish (Sociedad Espanola de Oncologia Medica (SEOM)), European (European Association for the study of liver-European Organization for Research and Treatment of Cancer (EASL-EORTC) and European Society for Medical Oncology-European Society of Digestive Oncology (ESMO-ESDO)), Asian (Asian Pacific Association for the Study of Liver (APASL)), Japanese (Japan Society of Hepatology (JSH)), Italian (Associazione Italiana Oncologia Medica (AIOM)) and German (S3) guidelines.

Results

All guidelines recommend resection as therapy of choice in healthy liver. Guidelines based on the Barcelona Clinic Liver Cancer staging system recommend resection for single HCC<2 cm and Child-Pugh A cirrhosis and for HCC≤5 cm with normal bilirubin and portal pressure, whereas transplantation is recommended for multiple tumours between Milan criteria and for single tumours ≤5 cm and advanced liver dysfunction. Patients with HCC and Child-Pugh C cirrhosis are not candidates for transplantation. JSH guidelines recommend LR for patients with Child-Pugh A/B with HCC without tumour size restriction; APASL guidelines in general exclude patients with Child-Pugh A from transplantation. In patients with Child-Pugh B, transplantation is the second-line therapy, if resection is not possible for patients within Milan criteria. German and Italian guidelines recommend transplantation for all patients within Milan criteria.

Conclusions

Whereas resection is the standard therapy of HCC in healthy liver, a standard regarding the indication for LR and transplantation for HCC in cirrhotic liver does not exist, although nearly all guidelines claim to be evidence based. Surprisingly, despite European guidelines, Germany and Italy use their own national guidelines which partially differ from the European. Possible solutions of the problems are discussed.