New perspectives in the assessment of future remnant liver

Value of gadoxetic acid-enhanced MR imaging for preoperative prediction of future liver regeneration after hemihepatectomy

PURPOSE

Liver resection is currently considered the most effective treatment for patients with liver cancer. To the best of our knowledge, no study has investigated the association between gadoxetic acid-enhanced magnetic resonance imaging (MRI) findings and liver regeneration in patients who underwent hemihepatectomy. We aimed to clarify the relationship between the signal intensity (SI) of the liver parenchyma on gadoxetic acid-enhanced MRI and the degree of liver regeneration in patients who underwent hemihepatectomy.

MATERIALS AND METHODS

Forty-one patients who underwent gadoxetic acid-enhanced MRI before hemihepatectomy were enrolled. We calculated the liver-to-erector spinae muscle SI ratio (LMR) in the hepatobiliary phase and the precontrast images. ΔLMR was calculated using the following equation: ΔLMR = (LMR in the hepatobiliary phase-LMR in the precontrast image)/LMR in the precontrast image. The preoperative and postoperative remnant liver volumes (LVs) were calculated using CT volumetry. We calculated the resection rate (RR) and liver regeneration index (LRI) using the following formulas: RR = Resected LV/Total LV × 100 and LRI = (postoperative remnant LV-preoperative remnant LV)/preoperative remnant LV × 100. The relationships among LRI, imaging, and clinicopathological factors were analyzed.

RESULTS

Univariate analysis showed RR and ΔLMR showed a positive correlation with LRI (ρ = 0.4133, p = 0.0072 and ρ = 0.7773, p < 0.001, respectively). Spleen volume showed a negative correlation with LRI (ρ = -0.3138, p = 0.0486). Stepwise multiple regression analysis showed ΔLMR and RR were independently correlated with LRI (β coefficient = 44.8771, p = 0.0198 and β coefficient = 1.9653, p < 0.001, respectively).

CONCLUSION

ΔLMR may serve as a preoperative predictor of liver regeneration in patients undergoing hemihepatectomy.

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.

A novel surgical scheme for hepatectomy in hepatocellular carcinoma patients with clinically significant portal hypertension

OBJECTIVE

Clinically significant portal hypertension (CSPH) seriously affects the feasibility and safety of surgical treatment for hepatocellular carcinoma (HCC) patients. The aim of this study was to establish a new surgical scheme defining risk classification of post-hepatectomy liver failure (PHLF) to facilitate the surgical decision-making and identify suitable candidates for individual hepatectomy among HCC patients with CSPH.

BACKGROUNDS

Hepatectomy is the preferred treatment for HCC. Surgeons must maintain a balance between the expected oncological outcomes of HCC removal and short-term risks of severe PHLF and morbidity. CSPH aggravates liver decompensation and increases the risk of severe PHLF thus complicating hepatectomy for HCC.

METHODS

Multivariate logistic regression and stochastic forest algorithm were performed, then the independent risk factors of severe PHLF were included in a nomogram to determine the risk of severe PHLF. Further, a conditional inference tree (CTREE) through recursive partitioning analysis validated supplement the misdiagnostic threshold of the nomogram.

RESULTS

This study included 924 patients, of whom 137 patients (14.8%) suffered from mild-CSPH and 66 patients suffered from (7.1%) with severe-CSPH confirmed preoperatively. Our data showed that preoperative prolonged prothrombin time, total bilirubin, indocyanine green retention rate at 15 min, CSPH grade, and standard future liver remnant volume were independent predictors of severe PHLF. By incorporating these factors, the nomogram achieved good prediction performance in assessing severe PHLF risk, and its concordance statistic was 0.891, 0.850 and 0.872 in the training cohort, internal validation cohort and external validation cohort, respectively, and good calibration curves were obtained. Moreover, the calculations of total points of diagnostic errors with 95% CI were concentrated in 110.5 (range 76.9-178.5). It showed a low risk of severe PHLF (2.3%), indicating hepatectomy is feasible when the points fall below 76.9, while the risk of severe PHLF is extremely high (93.8%) and hepatectomy should be rigorously restricted at scores over 178.5. Patients with points within the misdiagnosis threshold were further examined using CTREE according to a hierarchic order of factors represented by the presence of CSPH grade, ICG-R15, and sFLR.

CONCLUSION

This new surgical scheme established in our study is practical to stratify risk classification in assessing severe PHLF, thereby facilitating surgical decision-making and identifying suitable candidates for individual hepatectomy.

Multi-organ Radiomics-Based Prediction of Future Remnant Liver Hypertrophy Following Portal Vein Embolization

BACKGROUND

Portal vein embolization (PVE) is used to induce remnant liver hypertrophy prior to major hepatectomy. The purpose of this study was to evaluate the predictive value of baseline computed tomography (CT) data for future remnant liver (FRL) hypertrophy after PVE.

METHODS

In this retrospective study, all consecutive patients undergoing right-sided PVE with or without hepatic vein embolization between 2018 and 2021 were included. CT volumetry was performed before and after PVE to assess standardized FRL volume (sFRLV). Radiomic features were extracted from baseline CT after segmenting liver (without tumor), spleen and bone marrow. For selecting features that allow classification of response (hypertrophy ≥ 1.33), a stepwise dimension reduction was performed. Logistic regression models were fitted and selected features were tested for their predictive value. Decision curve analysis was performed on the test dataset.

RESULTS

A total of 53 patients with liver tumor were included in this study. sFRLV increased significantly after PVE, with a mean hypertrophy of FRL of 1.5 ± 0.3-fold. sFRLV hypertrophy ≥ 1.33 was reached in 35 (66%) patients. Three independent radiomic features, i.e. liver-, spleen- and bone marrow-associated, differentiated well between responders and non-responders. A logistic regression model revealed the highest accuracy (area under the curve 0.875) for the prediction of response, with sensitivity of 1.0 and specificity of 0.5. Decision curve analysis revealed a positive net benefit when applying the model.

CONCLUSIONS

This proof-of-concept study provides first evidence of a potential predictive value of baseline multi-organ radiomics CT data for FRL hypertrophy after PVE.

Postoperative Liver Failure: Definitions, Risk factors, Prediction Models and Prevention Strategies

BACKGROUND

Liver resection is the treatment for a variety of benign and malignant conditions. Despite advances in preoperative selection, surgical technique, and perioperative management, post hepatectomy liver failure (PHLF) is still a leading cause of morbidity and mortality following liver resection.

METHODS

A review of the literature was performed utilizing MEDLINE/PubMed and Web of Science databases in May of 2023. The MESH terms "liver failure," "liver insufficiency," and "hepatic failure" in combination with "liver surgery," "liver resection," and "hepatectomy" were searched in the title and/or abstract. The references of relevant articles were reviewed to identify additional eligible publications.

RESULTS

PHLF can have devastating physiological consequences. In general, risk factors can be categorized as patient-related, primary liver function-related, or perioperative factors. Currently, no effective treatment options are available and the management of PHLF is largely supportive. Therefore, identifying risk factors and preventative strategies for PHLF is paramount. Ensuring an adequate future liver remnant is important to mitigate risk of PHLF. Dynamic liver function tests provide more objective assessment of liver function based on the metabolic capacity of the liver and have the advantage of easy administration, low cost, and easy reproducibility.

CONCLUSION

Given the absence of randomized data specifically related to the management of PHLF, current strategies are based on the principles of management of acute liver failure from any cause. In addition, goal-directed therapy for organ dysfunction, as well as identification and treatment of reversible factors in the postoperative period are critical.

Intravoxel incoherent motion diffusion weighted imaging for preoperative evaluation of liver regeneration after hepatectomy in hepatocellular carcinoma

OBJECTIVES

To explore whether intravoxel incoherent motion (IVIM) parameters could evaluate liver regeneration preoperatively.

METHODS

A total of 175 HCC patients were initially recruited. The apparent diffusion coefficient, true diffusion coefficient (D), pseudodiffusion coefficient (D*), pseudodiffusion fraction (f), diffusion distribution coefficient, and diffusion heterogeneity index (Alpha) were measured by two independent radiologists. Spearman's correlation test was used to assess correlations between IVIM parameters and the regeneration index (RI), calculated as 100% × (the volume of the postoperative remnant liver - the volume of the preoperative remnant liver) / the volume of the preoperative remnant liver. Multivariate linear regression analyses were used to identify the factors for RI.

RESULTS

Finally, 54 HCC patients (45 men and 9 women, mean age 51.26 ± 10.41 years) were retrospectively analyzed. The intraclass correlation coefficient ranged from 0.842 to 0.918. In all patients, fibrosis stage was reclassified as F0-1 (n = 10), F2-3 (n = 26), and F4 (n = 18) using the METAVIR system. Spearman correlation test showed D* (r = 0.303, p = 0.026) was associated with RI; however, multivariate analysis showed that only D value was a significant predictor (p < 0.05) of RI. D and D*showed moderate correlations with fibrosis stage (r = -0.361, p = 0.007; r = -0.457, p = 0.001). Fibrosis stage showed a negative correlation with RI (r = -0.263, p = 0.015). In the 29 patients who underwent minor hepatectomy, only the D value showed a positive association (p < 0.05) with RI, and a negative correlation with fibrosis stage (r = -0.360, p = 0.018). However, in the 25 patients who underwent major hepatectomy, no IVIM parameters were associated with RI (p > 0.05).

CONCLUSIONS

The D and D* values, especially the D value, may be reliable preoperative predictors of liver regeneration.

KEY POINTS

• The D and D* values, especially the D value, derived from IVIM diffusion-weighted imaging may be useful markers for the preoperative prediction of liver regeneration in patients with HCC. • The D and D* values derived from IVIM diffusion-weighted imaging show significant negative correlations with fibrosis, an important predictor of liver regeneration. • No IVIM parameters were associated with liver regeneration in patients who underwent major hepatectomy, but the D value was a significant predictor of liver regeneration in patients who underwent minor hepatectomy.

Unsupervised Machine Learning of MRI Radiomics Features Identifies Two Distinct Subgroups with Different Liver Function Reserve and Risks of Post-Hepatectomy Liver Failure in Patients with Hepatocellular Carcinoma

OBJECTIVE

To identify subgroups of patients with hepatocellular carcinoma (HCC) with different liver function reserves using an unsupervised machine-learning approach on the radiomics features from preoperative gadoxetic-acid-enhanced MRIs and to evaluate their association with the risk of post-hepatectomy liver failure (PHLF).

METHODS

Clinical data from 276 consecutive HCC patients who underwent liver resections between January 2017 and March 2019 were retrospectively collected. Radiomics features were extracted from the non-tumorous liver tissue at the gadoxetic-acid-enhanced hepatobiliary phase MRI. The reproducible and non-redundant features were selected for consensus clustering analysis to detect distinct subgroups. After that, clinical variables were compared between the identified subgroups to evaluate the clustering efficacy. The liver function reserve of the subgroups was compared and the correlations between the subgroups and PHLF, postoperative complications, and length of hospital stay were evaluated.

RESULTS

A total of 107 radiomics features were extracted and 37 were selected for unsupervised clustering analysis, which identified two distinct subgroups (138 patients in each subgroup). Compared with subgroup 1, subgroup 2 had significantly more patients with older age, albumin-bilirubin grades 2 and 3, a higher indocyanine green retention rate, and a lower indocyanine green plasma disappearance rate (all p < 0.05). Subgroup 2 was also associated with a higher risk of PHLF, postoperative complications, and longer hospital stays (>18 days) than that of subgroup 1, with an odds ratio of 2.83 (95% CI: 1.58-5.23), 2.41(95% CI: 1.15-5.35), and 2.14 (95% CI: 1.32-3.47), respectively. The odds ratio of our method was similar to the albumin-bilirubin grade for postoperative complications and length of hospital stay (2.41 vs. 2.29 and 2.14 vs. 2.16, respectively), but was inferior for PHLF (2.83 vs. 4.55).

CONCLUSIONS

Based on the radiomics features of gadoxetic-acid-enhanced MRI, unsupervised clustering analysis identified two distinct subgroups with different liver function reserves and risks of PHLF in HCC patients. Future studies are required to validate our findings.

Clinical value of predictive models based on liver stiffness measurement in predicting liver reserve function of compensated chronic liver disease

BACKGROUND

Assessment of liver reserve function (LRF) is essential for predicting the prognosis of patients with chronic liver disease (CLD) and determines the extent of liver resection in patients with hepatocellular carcinoma.

AIM

To establish noninvasive models for LRF assessment based on liver stiffness measurement (LSM) and to evaluate their clinical performance.

METHODS

A total of 360 patients with compensated CLD were retrospectively analyzed as the training cohort. The new predictive models were established through logistic regression analysis and were validated internally in a prospective cohort (132 patients).

RESULTS

Our study defined indocyanine green retention rate at 15 min (ICGR15) ≥ 10% as mildly impaired LRF and ICGR15 ≥ 20% as severely impaired LRF. We constructed predictive models of LRF, named the mLPaM and sLPaM, which involved only LSM, prothrombin time international normalized ratio to albumin ratio (PTAR), age and model for end-stage liver disease (MELD). The area under the curve of the mLPaM model (0.855, 0.872, respectively) and sLPaM model (0.869, 0.876, respectively) were higher than that of the methods for MELD, albumin-bilirubin grade and PTAR in the two cohorts, and their sensitivity and negative predictive value were the highest among these methods in the training cohort. In addition, the new models showed good sensitivity and accuracy for the diagnosis of LRF impairment in the validation cohort.

CONCLUSION

The new models had a good predictive performance for LRF and could replace the indocyanine green (ICG) clearance test, especially in patients who are unable to undergo ICG testing.

Predictive value of Gd-EOB-DTPA -enhanced magnetic resonance imaging for post-hepatectomy liver failure: a systematic review and meta-analysis

Background

Accurate preoperative diagnosis of post-hepatectomy liver failure (PHLF) is particularly important to improve the prognosis of patients.

Purpose

To evaluate the predictive value of Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI) for post-hepatectomy liver failure.

Material and Methods

A systematic search was performed in the PubMed, Embase, the Cochrane Library, and Web of Science databases to find relevant original articles published up to December 2021. The included studies were assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. The bivariate random-effects model was used to assess the diagnostic authenticity. Meta-regression analyses were performed to analyze the potential heterogeneity.

Results

In total, 13 articles were included. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and the area under the summary receiver operating characteristic curves were 88% (95% confidence interval [CI] = 0.80–0.94), 80% (95% CI = 0.73–0.86), 4.4 (95% CI = 3.3–5.9), 0.14 (95% CI = 0.08–0.25), 31 (95% CI = 17–57), and 0.91 (95% CI = 0.89–0.94), respectively. There was no publication bias and threshold effect in our study.

Conclusion

Gd-EOB-DTPA-enhanced MRI is a potentially useful for the prediction of PHLF after major hepatectomy.

Developmental artificial neural network model to evaluate the preoperative safe limit of future liver remnant volume for HCC combined with clinically significant portal hypertension

Background & aims: Finding a way to comprehensively integrate the presence and grade of clinically significant portal hypertension, amount of preserved liver function and extent of hepatectomy into the guidelines for choosing appropriate candidates to hepatectomy remained challenging. This study sheds light on these issues to facilitate precise surgical decisions for clinicians. Methods: Independent risk factors associated with grade B/C post-hepatectomy liver failure were identified by stochastic forest algorithm and logistic regression in hepatitis B virus-related hepatocellular carcinoma patients. Results: The artificial neural network model was generated by integrating preoperative pre-ALB, prothrombin time, total bilirubin, AST, indocyanine green retention rate at 15 min, standard future liver remnant volume and clinically significant portal hypertension grade. In addition, stratification of patients into three risk groups emphasized significant distinctions in the risk of grade B/C post-hepatectomy liver failure. Conclusion: The authors' artificial neural network model could provide a reasonable therapeutic option for clinicians to select optimal candidates with clinically significant portal hypertension for hepatectomy and supplement the hepatocellular carcinoma surgical treatment algorithm.

Diagnostic accuracy of 3D imaging combined with intra-operative ultrasound in the prediction of post-hepatectomy liver failure

Background

The risk of post-hepatectomy liver failure (PHLF) is difficult to predict preoperatively. Accurate preoperative assessment of residual liver volume is critical in PHLF. Three-dimensional (3D) imaging and intra-operative ultrasound (IOUS) offer significant advantages in calculating liver volume and have been widely used in hepatectomy risk assessment. Our research aimed to explore the accuracy of 3D imaging technique combining IOUS in predicting PHLF after hepatectomy.

Methods

We used a retrospective study design to analyze patients who underwent hepatectomy with 3D imaging combined with IOUS between 2017 and 2020. Utilizing 3D reconstruction, the patient's residual liver volumes (PRLVs) and ratio of PRLV to standard liver volume (SLV) were calculated preoperatively. Hepatectomy were performed and actual hepatectomy volume (AHV) were measured. Consistency between preoperative planned hepatectomy volume (PPHV) and AHV was quantified postoperatively by Bland-Altman analysis. Multiple logistic regression and receiver-operating characteristic (ROC) curves were utilized to discuss the predictive value of PRLV/SLV in PHLF.

Results

Among the 214 included patients, 58 (27.1%) had PHLF. Patients with PHLF had significantly higher residual rates of ICG-R15 (%) (P=0.000) and a lower PRLV/SLV ratio (P=0.000). Bland-Altman analysis showed that PPHV was consistent with AHV (P=0.301). Multivariate analysis confirmed that PRLV/SLV ratio >60% (OR, 0.178; 95% CI: 0.084-0.378; P<0.01) was a protective factor for PHLF. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 75.8% (95% CI: 64.5.3-87.2%), 66.6% (95% CI: 59.1-74.1%), 45.8%, and 88.1%, respectively. The area under the ROC curve (AUC) was 73.7% (95% CI: 65.7-85.8%) and the diagnostic accuracy of PRLV/SLV for PHLF was moderate (P<0.001). These results were validated in the validation cohort perfectly. The primary cohort included 214 patients with a PHLF rate of 27.1% (n=58, 28 grade B and 13 grade C). The validation cohort included 135 patients with a PHLF rate of 35.6% (n=48, 24 grade B and 11 grade C).

Conclusions

The calculation of PRLV/SLV has predictive value in PHLF and can be exploited as a predictive factor. The 3D imaging technique combined with IOUS may be useful for PHLF risk assessment in hepatectomy patients.

A Novel Predictive Scoring System for 90-Day Mortality among Patients with Hepatocellular Cell Carcinoma Receiving Major Hepatectomy

Simple Summary

Hepatocellular carcinoma (HCC) is a major malignancy correlated with many cancer-related deaths. Surgical intervention provides superior long-term survival; however, perioperative mortality is a major concern for clinicians while making treatment decisions, especially for major hepatectomy. Scoring systems for predicting 90-day mortality in patients with HCC undergoing major hepatectomy are not available. By using the stepwise selection of the multivariate Cox proportional hazards model, we divided the patients with HCC receiving major hepatectomy into four risk groups. The Chang Gung-PohAi predictive scoring system showed significant differences in the 90-day mortality rate among the four risk groups (very low risk: 2.42%, low risk: 4.09%, intermittent risk: 17.1%, and high risk 43.6%). The Chang Gung-PohAi predictive scoring system is a promising tool for predicting 90-day perioperative mortality in patients with HCC undergoing major hepatectomy.

Abstract

Purpose: Hepatocellular carcinoma (HCC) is a major malignancy and the common cause of cancer-related deaths. Surgical intervention provides superior long-term survival outcomes; however, perioperative mortality is a major concern for clinicians while making treatment decisions, especially for major hepatectomy. Scoring systems for predicting 90-day mortality in patients with HCC undergoing major hepatectomy are not available. Methods: This study used the Taiwan Cancer Registry Database that is linked to the National Health Insurance Research Database to analyze data of 60,250 patients with HCC who underwent major hepatectomy and determine risk factors to establish a novel predictive scoring system. By using the stepwise selection of the multivariate Cox proportional hazards model, we divided the patients with HCC undergoing major hepatectomy into four risk groups. Results: The Chang Gung-PohAi predictive scoring system exhibited significant differences in the 90-day mortality rate among the four risk groups (very low risk: 2.42%, low risk: 4.09%, intermittent risk: 17.1%, and high risk: 43.6%). Conclusion: The Chang Gung-PohAi predictive scoring system is a promising tool for predicting 90-day perioperative mortality in patients with HCC undergoing major hepatectomy.

Current strategies to induce liver remnant hypertrophy before major liver resection

Hepatic resection is the gold standard for patients affected by primary or metastatic liver tumors but is hampered by the risk of post-hepatectomy liver failure. Despite recent improvements, liver surgery still requires excellent clinical judgement in selecting patients for surgery and, above all, efficient pre-operative strategies to provide adequate future liver remnant. The aim of this article is to review the literature on the rational, the preliminary assessment, the advantages as well as the limits of each existing technique for preparing the liver for major hepatectomy.

Comparison of nuclear imaging techniques and volumetric imaging for the prediction of postoperative mortality and liver failure in patients undergoing localized liver-directed treatments: a systematic review

Background/aims

Although volumetric imaging by computed tomography (CT) is the gold standard for preoperative assessment of the future liver remnant, nuclear imaging studies have shown promising data. This systematic review summarized the results from trials investigating volumetric and nuclear medicine imaging for the prediction of postoperative mortality and liver failure (LF).

Methods

MEDLINE and Web of Science were searched for papers investigating nuclear imaging methods for the prediction of postoperative clinical outcomes in patients undergoing local, liver-directed treatments. Only papers investigating both preoperative nuclear imaging and CT or magnetic resonance imaging (MR) for the prediction of postoperative mortality and/or LF were included.

Results

Twenty-five trials were qualified for this review. All trials but two used technetium-based tracers for the nuclear imaging examination. Four papers used MR imaging and the remaining used CT for the volumetric evaluation. Overall, the studies were heterogeneous both in terms of methodology and imaging technique. Of the thirteen studies reporting on postoperative mortality, most were descriptive without detailed diagnostic data. A few with detailed data found that nuclear imaging had better predictive value than volumetric imaging. Nineteen studies investigated the prediction of postoperative LF of which seven papers investigated the predictive value of both modalities in multivariable regression analysis. Two papers found that only nuclear imaging parameters were predictive of LF, one paper found that the CT parameter was predictive, and four papers found that combined nuclear and CT/MR imaging parameters were predictive of LF.

Conclusion

Both methodologies were useful in the preoperative assessment of patients scheduled for liver interventions, especially in combination, but nuclear imaging demonstrated better predictive value for postoperative mortality and LF in a few trials. The overall technical and methodological heterogeneity of the included studies complicates the ability to directly compare the clinical utility of the two imaging techniques.

Design and Usability Evaluations of a 3D-Printed Implantable Drug Delivery Device for Acute Liver Failure in Preclinical Settings

Acute liver failure (ALF) requiring liver transplantation is a disease that occurs due to rapid hepatocellular dysfunction. As liver transplantation has various limitations, including donor scarcity, high cost, and immuno-incompatibility, continuous local delivery of biopharmaceuticals to the liver tissue can be a promising ALF treatment option. Here, the in vivo safety and usability of a 3D-printed implantable drug delivery device for effective ALF treatment is evaluated. The implantable reservoir consists of a 3D-printed container and a semipermeable membrane for repeated administrations of drugs, specifically to the liver tissue. The physical stability and function of the 3D-printed reservoir are confirmed by the mechanical properties and in vitro drug release test, respectively. In mice implanted with the reservoir system, mortality, weight changes, clinical signs, hematological and serum biochemical changes, and organ weight changes are not observed, suggesting no foreign body reaction. The usability of the reservoir system is further evaluated using an ALF model of 70% hepatectomized mice treated with N-acetylcysteine through the system, showing cell-specific regeneration and significant liver injury alleviation. Overall, the 3D-printed reservoir system is safe for studying the therapeutic potential of ALF treatment, and it can be used for the delivery of various active pharmaceutical ingredients.

Comparison between preoperative two-dimensional shear wave elastography and indocyanine green clearance test for prediction of post-hepatectomy liver failure

Background

Post-hepatectomy liver failure (PHLF) is one of the most serious complications and major causes of liver resection mortality. The purpose of this study is to investigate and compare the performance of preoperative two-dimensional shear wave elastography (2D-SWE) and the indocyanine green (ICG) clearance test for the prediction of PHLF.

Methods

A total of 172 consecutive patients who were undergoing major liver resection were prospectively identified. Patients were evaluated by preoperative 2D-SWE and ICG clearance test. According to the International Study Group of Liver Surgery (ISGLS) recommendations, No PHLF, PHLF A, PHLF B, and PHLF C group classifications were defined. The differences in liver stiffness value (LSV) and ICG retention rate at 15 minutes (ICGR15) among the different PHLF classifications were investigated. The performance of LSV and ICGR15 for diagnosing different classifications of PHLF was compared.

Results

PHLF occurred in 43 (25.0%) patients, and 24 (14.0%) patients were grade A, 14 (8.1%) were grade B, and 5 (2.9%) were grade C. Both LSV and ICGR15 of the PHLF C group were significantly higher than those of the No PHLF group (P=0.025, P=0.001, respectively). According to univariate and multivariate logistic regression analysis, LSV and ICGR15 were significantly related to PHLF (P=0.051, P=0.084, respectively). For diagnosis of ≥ PHLF A, ≥ PHLF B, and ≥ PHLF C, the areas under the receiver operating characteristic curve (AUCs) for 2D-SWE were 0.624 [95% confidence interval (CI): 0.536-0.712, P=0.015], 0.699 (95% CI: 0.576-0.821, P=0.005), and 0.831 (95% CI: 0.737-0.925, P=0.01), respectively. The AUCs of the ICG clearance test were 0.631 (95% CI: 0.542-0.721, P=0.01), 0.570 (95% CI: 0.436-0.704, P=0.32), and 0.717 (95% CI: 0.515-0.920, P=0.098), respectively. The AUC of LSV for the diagnosis of ≥ PHLF A was comparable to that of ICGR15 (P=0.17). The AUCs of LSV were significantly higher than those of ICGR15 for the diagnosis of ≥ PHLF B (P=0.002) and C (P=0.038).

Conclusions

2D-SWE demonstrates the potential to aid in the prediction of the severity of PHLF. Our findings also suggest that the performance of 2D-SWE is better than the ICG clearance test.

Combining Aspartate Aminotransferase-to-Platelet Ratio Index with Future Liver Remnant to Assess Preoperative Hepatic Functional Reserve in Patients with Hepatocellular Carcinoma

BACKGROUND

Accurate preoperative assessment of hepatic functional reserve is essential for conducting a safe hepatectomy. In recent years, aspartate aminotransferase-to-platelet ratio index (APRI) has been used as a noninvasive model for assessing fibrosis stage, hepatic functional reserve, and prognosis after hepatectomy with a high level of accuracy. The purpose of this research was to evaluate the clinical value of combining APRI with standardized future liver remnant (sFLR) for predicting severe post-hepatectomy liver failure (PHLF) in patients with hepatocellular carcinoma (HCC).

METHODS

Six hundred thirty-seven HCC patients who had undergone hepatectomy were enrolled in this study. The performance of the Child-Pugh (CP) grade, model for end-stage liver disease (MELD), APRI, sFLR, and APRI-sFLR in predicting severe PHLF was assessed using the area under the ROC curve (AUC).

RESULTS

Severe PHLF was found to have developed in 101 (15.9%) patients. Multivariate logistic analyses identified that prealbumin, cirrhosis, APRI score, sFLR, and major resection were significantly associated with severe PHLF. The AUC values of the CP, MELD, APRI, and sFLR were 0.626, 0.604, 0.725, and 0.787, respectively, indicating that the APRI and sFLR showed significantly greater discriminatory abilities than CP and MELD (P < 0.05 for all). After APRI was combined with sFLR, the AUC value of APRI-sFLR for severe PHLF was 0.816, which greatly improved the prediction accuracy, compared with APRI or sFLR alone (P < 0.05 for all). Stratified analysis using the status of cirrhosis and extent of resection yielded similar results. Moreover, the incidence and grade of PHLF were significantly different among the three risk groups.

CONCLUSION

The combination of APRI and sFLR can be considered to be a predictive factor with increased accuracy for severe PHLF in HCC patients, compared with CP grade, MELD, APRI, or sFLR alone.

Surgical treatment of colorectal liver metastasis

Liver metastasis is the most common form of distant metastasis in colorectal cancer and is a key factor for prognosis in patients with colorectal cancer. Surgery may be the only way to cure colorectal liver metastases. This paper mainly summarizes the latest progress in surgical treatment of colorectal liver metastases, including how to increase resection rate of liver metastases with neoadjuvant therapy or staged hepatectomy, the effect of surgical margin on the prognosis of patients, the timing of surgery in patients with synchronous colorectal liver metastasis, the impact of laparoscopic hepatectomy of liver metastases, the application of liver transplantation in patients with colorectal liver metastases, etc, with an aim to help develop an optimal treatment for patients with colorectal liver metastases through combination of surgical innovations with individualized treatment, thereby improving patients' disease-free survival and overall survival.

Portal and hepatic vein embolization prior to major hepatectomy

PURPOSE

 To analyze safety and effectiveness of simultaneous portal and hepatic vein embolization (PHVE) or sequential hepatic vein embolization (HVE) compared to portal vein embolization (PVE) for future remnant liver (FRL) hypertrophy prior to major hepatic surgery.

METHODS

 Patients undergoing PVE, PHVE or HVE at our tertiary care center between 2018 and 2020 were retrospectively included. FRLV, standardized FRLV (sFRLV) and sFRLV growth rate per day were assessed via volumetry, as well as laboratory parameters.

RESULTS

 36 patients (f = 15, m = 21; median 64.5 y) were included, 16 patients received PHVE and 20 patients PVE, of which 4 received sequential HVE. Significant increase of FRLV was achieved with both PVE and PHVE compared to baseline (p < 0.0001). sFRLV growth rate did not significantly differ following PHVE (2.2 ± 1.2 %/d) or PVE (2.2 ± 1.7 %/d, p = 0.94). Left portal vein thrombosis (LPVT) was observed after PHVE in 6 patients and in 1 patient after PVE. Sequential HVE showed a considerably high growth rate of 1.42 ± 0.45 %/d after PVE.

CONCLUSION

 PHVE effectively induces FRL hypertrophy but yields comparable sFRLV to PVE. Sequential HVE further induces hypertrophy after insufficient growth due to PVE. Considering a potentially higher rate of LPVT after PHVE, PVE might be preferred in patients with moderate baseline sFRLV, with optional sequential HVE in non-sufficient responders.

Preoperative Remnant Liver Function Evaluation Using a Routine Clinical Dynamic Gd-EOB-DTPA-Enhanced MRI Protocol in Patients with Hepatocellular Carcinoma

BACKGROUND

To investigate the clinical feasibility of preoperative routine clinical dynamic Gd-EOB-DTPA-enhanced MRI alone to predict post-hepatectomy liver failure (PHLF) in patients with hepatocellular carcinoma (HCC).

METHODS

116 patients with HCC who underwent liver resection in Southwest Hospital from 2014 through 2017 were selected in this retrospective cohort study. The remnant function (RF) of the liver RF_UR and RF_RE15 were calculated by the sum of the uptake rate (UR) or relative enhancement at 15 min (RE15) from dynamic Gd-EOB-DTPA-enhanced MR images in the remnant liver regions, and standardized by standard liver volume (SLV) to generate sRF_UR (standardized RF_UR) and sRF_RE15 (standardized RF_RE15). Student's t test or Mann-Whitney U test, logistic regression, and ROC analyses were used to test the associations of preoperative RF_UR, sRF_UR, RF_RE15, sRF_RE15, the remnant liver volume (RLV)/SLV, ICG retention rate at 15 min (ICG R15) and sRF_ICG-K [ICG clearance rate (ICG-K) × RLV/SLV] with PHLF.

RESULTS

28 patients were found to have PHLF, who showed lower RF_UR, sRF_UR, RF_RE15, sRF_RE15, RLV/SLV, sRF_ICG-K, and higher ICG R15 than patients without PHLF (p < 0.001 for all). After adjusting for clinical parameters, RF_UR (p = 0.001), sRF_UR (p = 0.001), RF_RE15 (p = 0.002), or sRF_RE15 (p = 0.003) was found to be independently significant indicator in multivariable logistic regression, respectively. RF_UR (0.882) and sRF_UR (0.882) had larger AUCs than RLV/SLV (0.731, p = 0.008; p = 0.005), ICG R15 (0.765, p = 0.039; p = 0.044) and sRF_ICG-K (0.767, p = 0.031; p = 0.023). RF_RE15 (0.845) and sRF_RE15 (0.839) had larger AUCs than RLV/SLV (0.731, p = 0.027; p = 0.025).

CONCLUSIONS

The remnant liver function parameters preoperatively estimated from a routine clinical dynamic Gd-EOB-DTPA-enhanced MRI protocol can predict PHLF in patients with HCC, and may be better predictors than conventional methods.

Nomogram for prediction of the international study Group of Liver Surgery (ISGLS) grade B/C Posthepatectomy liver failure in HBV-related hepatocellular carcinoma patients: an external validation and prospective application study

BACKGROUND

To develop a nomogram for predicting the International Study Group of Liver Surgery (ISGLS) grade B/C posthepatectomy liver failure (PHLF) in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) patients.

METHODS

Patients initially treated with hepatectomy were included. Univariate regression analysis and stochastic forest algorithm were applied to extract the core indicators and reduce redundancy bias. The nomogram was then constructed by using multivariate logistic regression, and validated in internal and external cohorts, and a prospective clinical application.

RESULTS

There were 900, 300 and 387 participants in training, internal and external validation cohorts, with the morbidity of grade B/C PHLF were 13.5, 11.0 and 20.2%, respectively. The nomogram was generated by integrating preoperative total bilirubin, platelet count, prealbumin, aspartate aminotransferase, prothrombin time and standard future liver remnant volume, then achieved good prediction performance in training (AUC = 0.868, 95%CI = 0.836-0.900), internal validation (AUC = 0.868, 95%CI = 0.811-0.926) and external validation cohorts (AUC = 0.820, 95%CI = 0.756-0.861), with well-fitted calibration curves. Negative predictive values were significantly higher than positive predictive values in training cohort (97.6% vs. 33.0%), internal validation cohort (97.4% vs. 25.9%) and external validation cohort (94.3% vs. 41.1%), respectively. Patients who had a nomogram score < 169 or ≧169 were considered to have low or high risk of grade B/C PHLF. Prospective application of the nomogram accurately predicted grade B/C PHLF in clinical practise.

CONCLUSIONS

The nomogram has a good performance in predicting ISGLS grade B/C PHLF in HBV-related HCC patients and determining appropriate candidates for hepatectomy.

Nuclear imaging methods for the prediction of postoperative morbidity and mortality in patients undergoing localized, liver-directed treatments: a systematic review

Background

Several nuclear imaging methods may predict postoperative liver function and outcome, but none has achieved recommendations in clinical guidelines. The purpose of this systematic review was to summarize the existing knowledge on this topic.

Methods

MEDLINE and Web of Science were searched for studies investigating nuclear medicine imaging methods for the prediction of postoperative liver function in patients undergoing localized, liver-directed treatments. The postoperative endpoints were clinical outcome (morbidity and mortality) as well as measures of postoperative liver function, e.g., liver function assessed by biochemical tests or nuclear imaging.

Results

A total of 1352 references were identified, of which 82 fulfilled the eligibility criteria and were included in the review. Most studies (n = 63) were retrospective studies. The vast majority of studies assessed [^99mTc]Tc-galactosyl serum albumin (GSA) (n = 57) and [^99mTc]Tc-mebrofenin (n = 19). Liver resection was entirely or partly major (involved at least three segments) in 78 reports. There were notable variations in the research methodology, e.g., image acquisition, imaging variables, and endpoints. Thirty-seven studies reported on postoperative mortality, of which most reported descriptive data at the patient level. Of the four reports that performed multivariate analyses, two showed significant predictive results of isotope-based preoperative tests. Fifty-two papers presented data on postoperative liver failure. Multivariate predictive analyses were performed in eighteen trials, of which fifteen showed the significant value of nuclear medicine tests.

Conclusion

There is sparse evidence supporting the significant value of nuclear medicine imaging methods in predicting postoperative mortality. In contrast, a notable number of trials showed a significant prediction of liver failure in multivariate analyses. The research methodology was heterogeneous and exploratory in most trials. Documentation of nuclear medicine tests in this setting awaits the results of properly designed, prospective trials with the standardization of both the nuclear medicine test and endpoints.

The actual management of colorectal liver metastases

Colorectal cancer is one of the most frequent cancers in the world and between 50% and 60% of patients will develop colorectal liver metastases (CRLM) during the disease. There have been great improvements in the management of CRLM during the last decades. The combination of modern chemotherapeutic and biological systemic treatments with aggressive surgical resection strategies is currently the base for the treatment of patients considered unresectable until few years ago. Furthermore, several new treatments for the local control of CRLM have been developed and are now part of the arsenal of multidisciplinary teams for the treatment of these complex patients. The aim of this review was to summarize and update the management of CRLM, its controversies and relevant evidence.

Hepatic function assessment to predict post-hepatectomy liver failure: what can we trust? A systematic review

Post hepatectomy liver failure (PHLF) could occur even though an adequate liver volume is preserved. Liver function is not strictly related to the volume and the necessity to pre-operatively predict the future liver remnant (FLR) function is emerging, together with the wide spreading of techniques, aiming to optimize the FLR. The aim of this study was to systematically review all the available tests, to pre-operatively assess the liver function and to estimate the risk of PHLF. A systematic literature research of Medline, Embase, Scopus was performed in accordance to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, to identify all the studies available for pre-operative liver function tests to assess the risk of PHLF and/or complications. From the 1122 references retrieved, 79 were included in the review. Dynamic functional tests, such as indocyanine green test (ICG), could evaluate only global liver function, with no definition of functional capacity of the remnant. Magnetic resonance imaging (MRI) with liver-specific contrast agents enables both liver function and volume evaluation; the absence of ionizing radiation showed a better patient's compliance. Nuclear imaging studies as hepatobiliary scintigraphy (HBS) present the unique ability to allow a precise evaluation of the segmental liver function of the remnant liver. Liver volume could overestimate liver function. Several liver function tests are available to evaluate the risk of PHLF in the pre-operative setting. However, no single test alone could accurately predict PHLF. Pre-operative combination between a dynamic quantitative test, such as ICG, with MRI or HBS, should enable a more complete functional evaluation. Functional tests to predict PHLF should be chosen according to patient's characteristics, disease, and center experience.

The utility of 99mTc-mebrofenin hepatobiliary scintigraphy with SPECT/CT for selective internal radiation therapy in hepatocellular carcinoma

BACKGROUND

Studies assessing the impact of selective internal radiation therapy (SIRT) on the regional liver function in patients with hepatocellular carcinoma (HCC) are sparse. This study assessed the changes in total and regional liver function using hepatobiliary scintigraphy (HBS) and investigated the utility of HBS to predict post-SIRT liver dysfunction.

METHODS

Patients treated with SIRT for HCC between 2011 and 2019, underwent Tc-mebrofenin HBS with single-photon emission computed tomography/computed tomography (SPECT/CT) before and 6 weeks after SIRT. The corrected mebrofenin uptake rate (cMUR) and corresponding volume was measured in the total liver, and in treated and nontreated liver regions. Patients with and without post-SIRT liver dysfunction were compared.

RESULTS

A total of 29 patients, all Child-Pugh-A and mostly intermediate (72%) stage HCC were included in this study. Due to SIRT, the cMURtotal declined from 5.8 to 4.5%/min/m (P < 0.001). Twenty-two patients underwent a lobar SIRT, which induced a decline in cMUR (2.9-1.7%/min/m, P < 0.001) and volume (1228-1101, P = 0.002) of the treated liver region, without a change in cMUR (2.4-2.0%/min/m, P = 0.808) or volume (632-644 mL, P = 0.661) of the contralateral nontreated lobe. There were no significant pre-SIRT differences in total or regional cMUR or volume between patients with and without post-SIRT liver dysfunction.

CONCLUSION

In patients treated with SIRT for HCC, HBS accurately identified changes in total and regional liver function and may have a complementary role to personalize lobar or selective SIRT. In this pilot study, there were no pre-SIRT differences in cMUR or volume to aid in predicting post-SIRT liver dysfunction.

No alteration of Cyp3A4 activity after major hepatectomy in the early postoperative period - A prospective before-after study

BACKGROUND

The impact of major liver resection (LR) on the detoxifying function of the remaining liver tissue as represented by CYP3A activity has yet to be assessed. Therefore, this study evaluates the changes in CYP3A activity between preoperative values and after liver resection.

MATERIAL AND METHODS

To determine CYP3A activity, midazolam (MDZ) was used as a marker substance, 3 μg were applied intravenously one day before surgery and on the 3rd day after surgery. Subsequently blood was withdrawn at 0, 0.25, 0.5, 1.0, 1.5, 2.0, 2.5, 3, 4 and 6 h post application of the study drug. Plasma MDZ and 1-OH-MDZ concentration was assessed using a LC-MS/MS method. Volumetric analysis of the resected liver was done by syngo.CT liver analysis software (Siemens Healthineers) using preoperative multidetector computed tomography.

RESULTS

N = 13 (8 male/5 female) patients were included in this study and received preoperative evaluation, 11 patients were studied also after liver resection. The mean age was 62 (±15.3) years with a mean BMI of 23.6 ± 4.8 kg/m². No patient suffered from acute liver dysfunction postoperatively. None of the pharmacokinetic parameters assessed were significantly altered by liver resection. CYP3A activity over time was not significantly reduced by major liver resection.

CONCLUSION

This study gives first time data on the impact of major liver resection on CYP3A activity. It was shown that MDZ clearance representing in vivo CYP3A activity is not altered by major liver resection. This suggests no dose adjustment of commonly applied drugs which are CYP3A substrates needs to be carried out.

Improving the Safety of Major Resection for Hepatobiliary Malignancy: Portal Vein Embolization and Recent Innovations in Liver Regeneration Strategies

PURPOSE OF REVIEW

For three decades, portal vein embolization (PVE) has been the "gold-standard" strategy to hypertrophy the anticipated future liver remnant (FLR) in advance of major hepatectomy. During this time, CT volumetry was the most common method to preoperatively assess FLR quality and function and used to determine which patients are appropriate surgical candidates. This review provides the most up-to-date methods for preoperatively assessing the anticipated FLR and summarizes data from the currently available strategies used to induce FLR hypertrophy before surgery for hepatobiliary malignancy.

RECENT FINDINGS

Functional and physiological imaging is increasingly replacing standard CT volumetry as the method of choice for preoperative FLR assessment. PVE, associating liver partition and portal vein ligation, radiation lobectomy, and liver venous deprivation are all currently available techniques to hypertrophy the FLR. Each strategy has pros and cons based on tumor type, extent of resection, presence or absence of underlying liver disease, age, performance status, complication rates, and other factors. Numerous strategies can lead to FLR hypertrophy and improve the safety of major hepatectomy. Which is best has yet to be determined.

End-stage liver disease score and future liver remnant volume predict post-hepatectomy liver failure in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is the world’s sixth most common malignant tumor and the third cause of cancer death. Although great progress has been made in hepatectomy, it is still associated with a certain degree of risk of post-hepatectomy liver failure (PHLF), which extends the length of hospital stay and remains the leading cause of postoperative death. Studies have shown that assessment of hepatic functional reserve before hepatectomy is beneficial for reducing the incidence of PHLF.

AIM

To assess the value of model for end-stage liver disease (MELD) score combined with standardized future liver remnant (sFLR) volume in predicting PHLF in patients undergoing hepatectomy for HCC.

METHODS

This study was attended by 238 patients with HCC who underwent hepatectomy between January 2015 and January 2018. Discrimination of sFLR volume, MELD score, and sFLR/MELD ratio to predict PHLF was evaluated according to the area under the receiver operating characteristic curve.

RESULTS

The patients were divided into two groups according to whether PHLF occurred after hepatectomy. The incidence of PHLF was 8.4% in our research. The incidence of PHLF increased with the decrease in sFLR volume and the increase in MELD score. Both sFLR volume and MELD score were considered independent predictive factors for PHLF. Moreover, the cut-off value of the sFLR/MELD score to predict PHLF was 0.078 (P < 0.001). This suggests that an sFLR/MELD ≥ 0.078 indicates a higher incidence of PHLF than an sFLR/MELD < 0.078.

CONCLUSION

MELD combined with sFLR is a reliable and effective PHLF predictor, which is superior to MELD score or sFLR volume alone.

Selective occlusion of the hepatic artery and portal vein improves liver hypertrophy for staged hepatectomy

Background

To evaluate the safety and feasibility of selective occlusion of the hepatic artery and portal vein (SOAP) for staged hepatectomy (SOAPS) in patients with hepatocellular carcinoma (HCC)

Methods

From December 2014 to August 2018, 9 patients with unresectable HCC were chosen to undergo SOAPS. SOAP without liver partition was performed in the first stage. The second stage was performed when future liver remnant (FLR) was equal to or bigger than 40% of the standard liver volume (SLV). The growth rate of FLR, perioperative outcomes, and survival data was recorded.

Results

In the first stage, all the 9 patients completed SOAP. Two cases received radiological interventional method and 7 cases received open operation. None of them developed liver failure and died following SOAP. After SOAP, FLR increased 145.0 ml (115.0 to 210 ml) and 37.1% (25.6 to 51.7%) on average. The average time interval between the two stages was 14.1 days (8 to 18 days). In the second stage, no in-hospital deaths occurred after SOAPS. One patient suffered from liver failure after SOAPS, and artificial liver support was adopted and his total bilirubin level returned to normal after postoperative day 35. The alpha-fetoprotein level of 8 patients reduced to normal within 2 months after SOAPS. Among 9 patients, 5 patients survived, 4 patients died of intrahepatic recurrence, lung metastasis, or bone metastasis. In the 5 survived cases, bone metastasis and intrahepatic recurrence were found in 1 patient, intrahepatic recurrence was found in another patient, and the remaining 3 patients were free of recurrence. The median disease-free survival time and overall survival time were 10.4 and 13.9 months, respectively.

Conclusion

SOAP can facilitate rapid and sustained FLR hypertrophy, and SOAPS is safe and effective in patients with unresectable HCC.

Metal-Based Complexes as Pharmaceuticals for Molecular Imaging of the Liver

This article reviews the use of metal complexes as contrast agents (CA) and radiopharmaceuticals for the anatomical and functional imaging of the liver. The main focus was on two established imaging modalities: magnetic resonance imaging (MRI) and nuclear medicine, the latter including scintigraphy and positron emission tomography (PET). The review provides an overview on approved pharmaceuticals like Gd-based CA and ^99mTc-based radiometal complexes, and also on novel agents such as ⁶⁸Ga-based PET tracers. Metal complexes are presented by their imaging modality, with subsections focusing on their structure and mode of action. Uptake mechanisms, metabolism, and specificity are presented, in context with advantages and limitations of the diagnostic application and taking into account the respective imaging technique.

Initial systemic chemotherapeutic and targeted therapy strategies for the treatment of colorectal cancer patients with liver metastases

Introduction: The liver is the most common metastatic site in colorectal cancer with more than half the patients developing a liver metastasis either at the time of their diagnosis (synchronous) or later (metachronous). Surgical resection remains the principal curative approach that offers significant survival improvements. However, upfront surgery is only possible in about 10-20% of patients at the time of diagnosis, making the consideration of other treatment modalities essential. Areas covered: In this review, the authors provide an overview of the standard approaches for the initial management of patients with colorectal cancer with liver metastases. They then provide an up-to-date discussion of first-line systemic chemotherapy/targeted therapy options in the contexts of initially resectable and unresectable disease and review toxicities and complications following these options. Expert opinion: Advances in chemotherapeutic agents and biological targeted therapies have improved the prognosis of colorectal cancer with liver metastases. However, there is still no 'single best approach', making further trials necessary to provide more evidence.

Somatostatin and the "Small-For-Size" Liver

“Small-for-size” livers arising in the context of liver resection and transplantation are vulnerable to the effects of increased portal flow in the immediate postoperative period. Increased portal flow is an essential stimulus for liver regeneration. If the rise in flow and stimulus for regeneration are excessive; however, liver failure and patient death may result. Somatostatin is an endogenous peptide hormone that may be administered exogenously to not only reduce portal blood flow but also offer direct protection to different cells in the liver. In this review article, we describe key changes that transpire in the liver following a relative size reduction occurring in the context of resection and transplantation and the largely beneficial effects that peri-operative somatostatin therapy may help achieve in this setting.

Mesenchymal Stem Cells Improve Glycometabolism and Liver Regeneration in the Treatment of Post-hepatectomy Liver Failure

Background

The mortality rate of post-hepatectomy liver failure (PHLF) remains very high, and liver transplantation is the only effective treatment regimen for PHLF. Cell transplantation is a potential treatment for liver diseases. Previous studies have proved that mesenchymal stem cells (MSCs) have immunomodulatory functions. In the present study, we found that MSCs promoted glycogen synthesis and liver regeneration in the treatment of PHLF. MSC transplantation also improved the survival rate of rats after 90% partial hepatectomy (PH). In our current study, we aimed to determine the efficacy and mechanism of MSC transplantation in the treatment of PHLF.

Methods

Mesenchymal stem cells were isolated from Sprague-Dawley rats and cultured using a standardized protocol. The MSCs were transplanted to treat acute liver failure induced by 90% PH. The therapeutic efficacy of MSCs on PHLF was verified through measuring alanine transaminase (ALT), aspartate aminotransferase (AST), international normalized ratio (INR), serum ammonia, liver weight to body weight ratio, blood glucose, and histology. To further study the mechanism of MSC transplantation in treatment for PHLF, we assessed the changes in the AKT/glycogen synthase kinase-3β (GSK-3β)/β-catenin pathway. A-674563 (AKT inhibitor) and SB216763 (GSK-3β inhibitor) were employed to validate our findings. SPSS version 19.0 was used for statistical analysis, and the independent-samples t-test was carried out to analyze the collected data.

Results

Mesenchymal stem cell transplantation attenuated the liver injury in acute liver failure induced by 90% PH. MSC transplantation improved the glucose metabolism and survival rate in the PHLF model. The effect of MSC transplantation on hepatocyte proliferation might be related to AKT/GSK-3β/β-catenin pathway.

Conclusion

Mesenchymal stem cell transplantation could be use as a potential treatment for PHLF.

Colorectal liver metastases: An update on multidisciplinary approach

Liver metastasis is the commonest form of distant metastasis in colorectal cancer. Selection criteria for surgery and liver-directed therapies have recently been extended. However, resectability remains poorly defined. Tumour biology is increasingly recognized as an important prognostic factor; hence molecular profiling has a growing role in risk stratification and management planning. Surgical resection is the only treatment modality for curative intent. The most appropriate surgical approach is yet to be established. The primary cancer and the hepatic metastasis can be removed simultaneously or in a two-step approach; these two strategies have comparable long-term outcomes. For patients with a limited future liver remnant, portal vein embolization, combined ablation and resection, and associating liver partition and portal vein ligation for staged hepatectomy have been advocated, and each has their pros and cons. The role of neoadjuvant and adjuvant chemotherapy is still debated. Targeted biological agents and loco-regional therapies (thermal ablation, intra-arterial chemo- or radio-embolization, and stereotactic radiotherapy) further improve the already favourable results. The recent debate about offering liver transplantation to highly selected patients needs validation from large clinical trials. Evidence-based protocols are missing, and therefore optimal management of hepatic metastasis should be personalized and determined by a multi-disciplinary team.

Semi-automated computed tomography Volumetry can predict hemihepatectomy specimens' volumes in patients with hepatic malignancy

Background

One of the major causes of perioperative mortality of patients undergoing major hepatic resections is post-hepatectomy liver failure (PHLF). For preoperative appraisal of the risk of PHLF it is important to accurately predict resectate volume and future liver remnant volume (FLRV). The objective of our study is to prospectively evaluate the accuracy of hemihepatectomy resectate volumes that are determined by computed tomography volumetry (CTV) when compared with intraoperatively measured volumes and weights as gold standard in patients undergoing hemihepatectomy.

Methods

Twenty four patients (13 women, 11 men) scheduled for hemihepatectomy due to histologically proven primary or secondary hepatic malignancies were included in our study. CTV was performed using a semi-automated module (S, hereinafter) (syngo.CT Liver Analysis VA30, Siemens Healthcare, Germany). Conversion factors between CT volumes on the one side and intraoperative volumes and weights on the other side were calculated using the method of least squares. Absolute and relative disagreements between CT volumes and intraoperative volumes were determined.

Results

A conversion factor of c = 0.906 most precisely predicted intraoperative volumes of exsanguinated hemihepatectomy specimens from CT volumes in all patients with mean absolute and relative disagreements between CT volumes and intraoperative volumes of 57 ml and 6.3%. The use of operation-specific conversion factors yielded even better results.

Conclusions

CTV performed with S accurately predicts intraoperative volumes of hemihepatectomy specimens when applying conversion factors which compensate for exsanguination. This allows to precisely estimate the FLRV and thus minimize the risk of PHLF in patients undergoing major hepatic resections.

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.

Modern work-up and extended resection in perihilar cholangiocarcinoma: the AMC experience

AIM

Perihilar cholangiocarcinoma (PHC) is a challenging disease and requires aggressive surgical treatment in order to achieve curation. The assessment and work-up of patients with presumed PHC is multidisciplinary, complex and requires extensive experience. The aim of this paper is to review current aspects of diagnosis, preoperative work-up and extended resection in patients with PHC from the perspective of our own institutional experience with this complex tumor.

METHODS

We provided a review of applied modalities in the diagnosis and work-up of PHC according to current literature. All patients with presumed PHC in our center between 2000 and 2016 were identified and described. The types of resection, surgical techniques and outcomes were analyzed.

RESULTS AND CONCLUSION

Upcoming diagnostic modalities such as Spyglass and combinations of serum biomarkers and molecular markers have potential to decrease the rate of misdiagnosis of benign, inflammatory disease. Assessment of liver function with hepatobiliary scintigraphy provides better information on the future remnant liver (FRL) than volume alone. The selective use of staging laparoscopy is advisable to avoid futile laparotomies. In patients requiring extended resection, selective preoperative biliary drainage is mandatory in cholangitis and when FRL is small (< 50%). Preoperative portal vein embolization (PVE) is used when FRL volume is less than 40% and optionally includes the left portal vein branches to segment 4. Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) as alternative to PVE is not recommended in PHC. N2 positive lymph nodes preclude long-term survival. The benefit of unconditional en bloc resection of the portal vein bifurcation is uncertain. Along these lines, an aggressive surgical approach encompassing extended liver resection including segment 1, regional lymphadenectomy and conditional portal venous resection translates into favorable long-term survival.

Combining albumin-bilirubin score with future liver remnant predicts post-hepatectomy liver failure in HBV-associated HCC patients

BACKGROUND AND AIMS

Accurate assessment of liver functional reserve pre-operatively is vital for safe hepatic resection. The ALBI score is a new model for assessing liver function. This study aimed to evaluate the value of combining ALBI score with sFLR in predicting post-operative morbidity and PHLF in HCC patients who underwent hepatectomy.

METHODS

Patients undergoing three-dimensional CT reconstruction prior to hepatectomy for HCC between January 2015 and January 2017 were enrolled. The values of the CP score, ALBI score and sFLR in predicting post-operative outcomes were evaluated.

RESULTS

A total of 229 HCC patients were enrolled; 24 (10.5%) experienced major complications and 21 (9.2%) developed PHLF. The incidence of major complications and PHLF increased with increasing ALBI grade. The ALBI grade classified patients with CP grade A into two subgroups with different incidences of PHLF (P=.029). sFLR and ALBI scores were identified as independent predictors of PHLF. The AUC values for the CP score, ALBI score, sFLR and sFLR×ALBI for predicting major complications were 0.600, 0.756, 0.660 and 0.790 respectively. The AUC values of the CP score, ALBI score, sFLR and sFLR×ALBI for predicting PHLF were 0.646, 0.738, 0.758 and 0.884 respectively.

CONCLUSIONS

The ALBI score showed superior predictive value of post-operative outcomes over CP score, and the combination of sFLR and ALBI score was identified as a stronger predictor of post-operative outcomes than the sFLR or ALBI score alone.

Resection for Klatskin tumors: technical complexities and results

Klatskin's tumors, actually-redefined as perihilar cholangiocarcinoma (phCCA) do represent 50-70% of all CCAs and develop in a context of chronic inflammation and cholestasis of bile ducts. Surgical resection provides the only chance of cure for this disease but is technically challenging because of the complex, intimate and variable relationship between biliary and vascular structures at this location. Five years survival rates range between 25-45% (median 27-58 months) in case of R0 resection and 0-23% (median 12-21 months) in case of R1 resection respectively. It should be noted that the major costs of high radicality are represented by relative high morbidity and mortality rates (i.e., 20-66% and 0-9% respectively). Considering the fact that radical resection may represent the only curative treatment of phCCA, we focused our review on surgical planning and techniques that may improve resectability rates and outcomes for locally advanced phCCA. The surgical treatment of phCCA can be successful when following aspects have been fulfilled: (I) accurate preoperative diagnostic aimed to identify the tumor in all its details (localization and extension) and to study all the risk factors influencing a posthepatectomy liver failure (PHLF): i.e., liver volume, liver function, liver quality, haemodynamics and patient characteristics; (II) High end surgical skills taking in consideration the local extension of the tumor and the vascular invasion which usually require an extended hepatic resection and often a vascular resection; (III) adequate postoperative management aimed to avoid major complications (i.e., PHLF and biliary complications). These are technically challenging operations and must be performed in a high volume centres by hepato-biliary-pancreas (HBP)-surgeons with experience in microsurgical vascular techniques.

Current Modalities for the Assessment of Future Remnant Liver Function

While imaging studies such as computed tomography or magnetic resonance imaging allow the volumetric assessment of the liver segments, only indirect information is provided concerning the quality of the liver parenchyma and its actual functional capacity. Assessment of liver function is therefore crucial in the preoperative workup of patients who require extensive liver resection and in whom portal vein embolization is considered. This review deals with the modalities currently available for the measurement of liver function. Passive liver function tests include biochemical parameters and clinical grading systems such as the Child-Pugh and MELD scores. Dynamic quantitative tests of liver function can be based on clearance capacity tests such as the indocyanine green (ICG) clearance test. Although widely used, discrepancies have been reported for the ICG clearance test in relation with clinical outcome. Nuclear imaging studies have the advantage of providing simultaneous morphologic (visual) and physiologic (quantitative functional) information about the liver. In addition, regional (segmental) differentiation allows specific functional assessment of the future remnant liver. Technetium-99m (^99mTc)-galactosyl human serum albumin scintigraphy and ^99mTc-mebrofenin hepatobiliary scintigraphy potentially identify patients at risk for post-resectional liver failure who might benefit from liver-augmenting techniques. As there is no one test that can measure all the components of liver function, liver functional reserve is estimated based on a combination of clinical parameters and quantitative liver function tests.

99mTc-mebrofenin hepatobiliary scintigraphy predicts liver failure following major liver resection for perihilar cholangiocarcinoma

BACKGROUND

Posthepatectomy liver failure (PHLF) is a threatening complication after liver surgery, especially in perihilar cholangiocarcinoma (PHC). This study aimed to assess the value of preoperative assessment of liver function using ^99mTc-mebrofenin hepatobiliary scintigraphy (HBS) to predict PHLF in comparison with liver volume in PHC patients.

METHODS

All patients who underwent resection of suspected PHC in a single center between 2000 and 2015 were included in the analysis. PHLF was graded according to the ISGLS criteria with grade B/C considered clinically relevant. A cut-off value for the prediction of PHLF was calculated using the receiver operating characteristic curve (ROC) analysis.

RESULTS

A total of 116 patients were included of which 27 (23%) suffered of PHLF. ROC values for the prediction of PHLF were 0.74 (0.63-0.86) for future liver remnant function and 0.63 (0.47-0.80) for volume. A cut-off for liver function was set at 8.5%/min, which resulted in a negative predictive value of 94% and positive predictive value of 41%.

CONCLUSIONS

Assessment of liver function with HBS had better predictive value for PHLF than liver volume in patients undergoing major liver resection for suspected PHC. The cut-off of 8.5%/min can help to select patients for portal vein embolization and might help to reduce postoperative liver failure.

Use of the liver maximum function capacity test (LiMAx) for the management of liver resection in cirrhosis - A case of hypopharyngeal cancer liver metastasis

•

A patient with a liver metastasis of pharyngeal cancer and aspect of severe cirrhosis is presented.

•

Conventional laboratory tests are surrogate parameters and might underestimate cirrhosis.

•

The LiMAx test provides a direct measurement of the liver function capacity even in cirrhosis.

•

Safe resection was performed after LiMAx test proved operability.

Introduction

The presence of liver cirrhosis goes along with a higher chance for the need of liver resection. As established laboratory parameters often underestimate the degree of cirrhosis this is associated with an increased risk for postoperative liver failure due to the preoperatively impaired liver function. Known liver function tests are unlikely to be performed in daily use because of high cost or expenditure of time. Liver maximum function capacity test (LiMAx) provides a novel tool for measurement of liver function and references for the safety of liver resection.

Presentation of case

A 63-year old patient presented at our hospital with a large, solitary liver metastasis from hypopharyngeal cancer in segments VII/VIII with infiltration of the diaphragm. Liver resection was unsuccessful in a peripheral hospital 10 months before due to considerable macroscopic liver cirrhosis (CHILD B). Upon presentation conventional laboratory parameters revealed sufficient liver function. LiMAx was performed and showed regular liver function (354 μg/kg/h; at norm >315 μg/kg/h). Consequently, atypical liver resection (R0) was performed resulting in a postoperative LiMAx value of 281 μg/h/kg (>150 μg/kg/h). The patient was discharged from hospital 37 days after surgery without any signs of postoperative liver failure.

Conclusion

The LiMAx-test enables determination of liver function at a so far unavailable level (metabolism via cytochrome P450 1A2) and hence might provide crucial additional diagnostic information to allow for safe liver resection even in cirrhotic patients.

Two-stage hepatectomy for multiple giant alveolar echinococcosis

Alveolar echinococcosis is a chronically progressive and potentially fatal disease. Patients with multiple giant alveolar echinococcosis have a poor prognosis when radical resection cannot be achieved, but curative resection can be limited by low future remnant liver volumes. In these cases, 2-stage liver resection may be a better choice: after a first-stage hepatectomy with partial resection, liver regeneration is allowed in the residual liver before proceeding to the second-stage hepatectomy. In this study, we therefore retrospectively reviewed and evaluated the safety and feasibility of two-stage hepatectomy in patients with multiple giant alveolar echinococcosis.We reviewed the data for all patients who underwent 2-stage hepatectomy for multiple giant alveolar echinococcosis between August 2013 and December 2015 at either the West China Hospital of Sichuan University or the Hospital of Ganzi Tibetan Autonomous Prefecture.We identified 7 patients in whom 2-stage hepatectomy was completed. During the first-stage hepatectomy, 4 patients underwent right-sided hepatectomy and the other 3 underwent left-sided hepatectomy. The second-stage hepatectomies were successfully performed 3 months after the first-stage procedures. All patients had follow-up durations of >1 year; there were no cases of operation-related mortality, and no patients experienced disease recurrence.Two-stage hepatectomy is safe and feasible for patients with multiple giant alveolar echinococcosis.

Integration of Child-Pugh score with future liver remnant yields improved prediction of liver dysfunction risk for HBV-related hepatocellular carcinoma following hepatic resection

Assessment of hepatic functional reserve is important to enable the selection of appropriate treatment methods and safe hepatic resection in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). In the present study, an evaluation was made of the clinical value of combining the Child-Pugh score (CPS) with the standardized future liver remnant (sFLR) measurement to predict postoperative liver dysfunction (PLD). A total of 61 HBV-related HCC patients undergoing liver volumetry prior to hepatectomy were enrolled in the study. The sFLR was calculated as the ratio of FLR volume to standardized liver volume. PLD was defined as a prothrombin time of >18 sec or a peak serum bilirubin level of >51.3 µmol/l for 7 days after surgery. Univariate analysis and multivariate logistic regression analysis were performed to identify risk factors associated with PLD. The correlation between PLD and the combination of sFLR and CPS was analyzed. In total, 18 out of 61 patients developed PLD (29.5%), with a significantly higher PLD incidence for a CPS of 6 than a CPS of 5 (P<0.05). Multivariate logistic regression analysis revealed that a prothrombin time of <13.3 sec and an sFLR of <0.55 were independent risk factors for PLD. Receiver operating characteristic (ROC) curve analysis revealed that the cut-off values of sFLR and sFLR/CPS for predicting PLD were 54.5% and 0.0916, respectively, with areas under the ROC curve of 0.820 and 0.860, respectively. The combination of CPS and sFLR appears to yield improved prediction of the occurrence of PLD compared with either CPS or sFLR alone.