Indications, limitations and maneuvers to enable extended hepatectomy: Current trends

Rapid Self-Assembly Mini-Livers Protect Mice Against Severe Hepatectomy-Induced Liver Failure

The construction of bioartificial livers, such as liver organoids, offers significant promise for disease modeling, drug development, and regenerative medicine. However, existing methods for generating liver organoids have limitations, including lengthy and complex processes (taking 6-8 weeks or longer), safety concerns associated with pluripotency, limited functionality of pluripotent stem cell-derived hepatocytes, and small, highly variable sizes (typically ≈50-500 µm in diameter). Prolonged culture also leads to the formation of necrotic cores, further restricting size and function. In this study, a straightforward and time-efficient approach is developed for creating rapid self-assembly mini-livers (RSALs) within 12 h. Additionally, primary hepatocytes are significantly expanded in vitro for use as seeding cells. RSALs exhibit consistent larger sizes (5.5 mm in diameter), improved cell viability (99%), and enhanced liver functionality. Notably, RSALs are functionally vascularized within 2 weeks post-transplantation into the mesentery of mice. These authentic hepatocyte-based RSALs effectively protect mice from 90%-hepatectomy-induced liver failure, demonstrating the potential of bioartificial liver-based therapy.

An explainable machine learning model to predict early and late acute kidney injury after major hepatectomy

BACKGROUND

Risk assessment models for acute kidney injury (AKI) after major hepatectomy that differentiate between early and late AKI are lacking. This retrospective study aimed to create a model predicting AKI through machine learning and identify features that contribute to the development of early and late AKI.

METHODS

Patients that underwent major hepatectomy were categorized into the No-AKI, Early-AKI (within 48 h) or Late-AKI group (between 48 h and 7 days). Modeling was done with 20 perioperative features and the performance of prediction models were measured by the area under the receiver operating characteristic curve (AUROCC). Shapley Additive Explanation (SHAP) values were utilized to explain the outcome of the prediction model.

RESULTS

Of the 1383 patients included in this study, 1229, 110 and 44 patients were categorized into the No-AKI, Early-AKI and Late-AKI group, respectively. The CatBoost classifier exhibited the greatest AUROCC of 0.758 (95% CI: 0.671-0.847) and was found to differentiate well between Early and Late-AKI. We identified different perioperative features for predicting each outcome and found 1-year mortality to be greater for Early-AKI.

CONCLUSIONS

Our results suggest that risk factors are different for Early and Late-AKI after major hepatectomy, and 1-year mortality is greater for Early-AKI.

Reversal of liver failure using a bioartificial liver device implanted with clinical-grade human-induced hepatocytes

Liver resection is the first-line treatment for primary liver cancers, providing the potential for a cure. However, concerns about post-hepatectomy liver failure (PHLF), a leading cause of death following extended liver resection, have restricted the population of eligible patients. Here, we engineered a clinical-grade bioartificial liver (BAL) device employing human-induced hepatocytes (hiHeps) manufactured under GMP conditions. In a porcine PHLF model, the hiHep-BAL treatment showed a remarkable survival benefit. On top of the supportive function, hiHep-BAL treatment restored functions, specifically ammonia detoxification, of the remnant liver and facilitated liver regeneration. Notably, an investigator-initiated study in seven patients with extended liver resection demonstrated that hiHep-BAL treatment was well tolerated and associated with improved liver function and liver regeneration, meeting the primary outcome of safety and feasibility. These encouraging results warrant further testing of hiHep-BAL for PHLF, the success of which would broaden the population of patients eligible for liver resection.

Early Outcomes of Extended Hepatectomy: An Experience from the University Hospital of Nepal

Background Extended hepatectomy (≥ 5 liver segments resection) may be required to have a complete surgical resection and provide the best chance of cure of hepatobiliary tumors. It is associated with high morbidity and mortality but with good perioperative care, its outcomes can be improved. This study was conducted to evaluate the early outcomes of extended hepatectomy at a university hospital in Nepal. Methods For this study, prospectively collected data from all patients who underwent extended hepatectomy from October 2012 to April 2022 were reviewed and analyzed retrospectively. Demographic data, liver volume augmentation methods used, intraoperative variables, and postoperative complications were analyzed. Results Seventeen patients underwent extended hepatectomy from October 2012 to April 2022. Among them 11 (64.7%) were female and the mean age was 53.9 ±16.3 years (18-72 years). Right extended hepatectomy was the most commonly performed procedure (n = 15, 88.2%), and left extended hepatectomy was performed in the remaining (n = 2, 11.8%). Six patients underwent liver volume augmentation procedures (35.3%) with portal vein embolization (PVE) in three, portal vein ligation (PVL) in one, and partial associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) in two patients. Overall complications were 70% with major complications (Clavien Dindo ≥ IIIa) constituting 35.3%. The most common hepatectomy-specific complication was post-hepatectomy liver failure (PHLF) in six cases. The 30-day mortality was 17.6% (three patients). Conclusion Extended hepatectomy can be performed with acceptable major complications and mortality rates in selected patients.

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

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

Indications and Complications of Hepatic Resection Patients at Sher-I-Kashmir Institute of Medical Sciences: An Observational Study

Aim: This study aimed to determine the indications and demographic profile of hepatic resection at Sher-I-Kashmir Institute of Medical Sciences (SKIMS), the performed types of hepatic resection, as well as assess the details of the operation and perioperative complications of hepatic resection.

Methods: This is a prospective, retrospective observational study. The retrospective study period was from January 2005 to August 2015 and the prospective study period was from 2015 till 2017. Prospective patients were clinically evaluated by medical history and clinical examination and also underwent various investigations. The patients were scored on Child-Pugh and American Society of Anesthesiology (ASA) scores for risk stratification and prepared for surgery, which included segmentectomy to major liver resection. The retrospective data were obtained from the Medical Records Department (MRD). Statistical analysis was done on SPSS software 25.0 version (Armonk, NY: IBM Corp.).

Results: This study included 122 patients with a male to female ratio of 1:1.59. The patients' age was between 1 and 73 years. The patients' most common complaint was right upper quadrant abdominal pain. The main established clinical diagnosis was oriental cholangiohepatitis (OCH) (36.9%) followed by carcinoma of gallbladder (CaGB) which accounted for 37 cases (30.4%). Liver metastases including solitary masses and multiple lesions were 10 cases (8.2%). Fifty-five patients underwent left lateral segmentectomy (45.1%) and mostly for OCH. Standard wedge resection was done in 30.7% of cases and for all cases of CaGB. The mean blood loss was 146.5 ml. A total of 37 patients had complications. Wound infection was the most common complication, occurring in 10 patients (8.2%).

Conclusion: Patients with hepatobiliary pathology, necessitating liver resection are now routinely admitted to the Department of Surgical Gastroenterology in SKIMS, Srinagar. Patients are carefully evaluated and operated with a confirmed definitive diagnosis. The overall surgical outcome does not differ from India's best centers.

Acute mental change as the presenting sign of posthepatectomy hepatic failure: A case report

RATIONALE

Hepatectomy is a treatment to increase survival and curability of patients with intrahepatic lesions or malignant tumors. However, posthepatectomy liver failure (PHLF) can occur. This case is a patient showing acute mental change in postanesthetic care unit (PACU) as an uncommon symptom of PHLF after extended right hepatectomy.

PATIENT CONCERNS

A 68-year-old male patient was admitted for surgery of Klatskin tumor. He had hypertension and atrial fibrillation. His model for end-stage liver disease score was 16 pts. His serum bilirubin and ammonia levels were 4.75 mg/dL and 132.8 mcg/dL, respectively. Other laboratory data were nonspecific. He underwent extended right hepatic lobectomy including segments IV-VIII for 9 hours. Weight of liver specimen was 1028 g which was about 58% of total liver volume based on computed tomographic volumetry. The patient was extubated and moved to the PACU with stable vital sign and regular self-breathing. He could obey verbal commands. Fifteen minutes after admission to the PACU, the patient showed abruptly decreasing mental status and self-breathing.

DIAGNOSES

Brain computed tomography, blood culture, and sputum culture were performed to diagnose brain lesions and sepsis for evaluating the sudden onset comatous mental status. Results showed nonspecific finding.

INTERVENTIONS

He was intubated for securing airway and applying ventilatory care. The patient was moved to the intensive care unit. He received intensive conservative therapy including continuous renal replacement therapy and broad-spectrum antibiotics.

OUTCOMES

The patient's condition was worsened. He expired on postoperative day 3.

LESSONS

Acute mental change is uncommon and rare as initial symptoms of PHLF. Therefore, clinician may overlook the diagnosis of PHLF in patients with acute mental change after hepatectomy. Thus, clinician should plan an aggressive treatment for PHLF including liver transplantation by recognizing any suspicious symptom, although such symptom is rare.

Outcomes of extended hepatectomy for hepatobiliary tumors. Initial experience from a non-university hepatobiliary center

INTRODUCTION

Hepatectomy is the gold standard curative treatment for hepatic neoplasms in patients with preserved liver function. Many large tumors require extended hepatectomy (EH). Possibility of developing major postoperative complications including liver failure is feared by many surgeons. We aim to describe our outcomes of EH for large hepatobiliary tumors.

MATERIAL AND METHODS

All patients undergoing hepatectomy between 2012 and 2017 were prospectively followed.

RESULTS

91 patients underwent hepatectomy with ten patients underwent EH. The majority of patients were women, age of 63, BMI of 24, and MELD score of 11. Six patients underwent an extended right hepatectomy, while four patients underwent extended left hepatectomy. Operative time was 224 min with estimated blood loss of 500 ml. No intraoperative complications were seen. Two patients experienced postoperative complications (pleural effusion in one patient and respiratory failure in another). Length of ICU stay was 2 days, and hospital stay was 5 days. 80% of the patients are currently alive with median follow-up of 41.2 months.

CONCLUSION

EH can be undertaken safely with acceptable morbidity and mortality in our center.

Low-Power Laser Irradiation (LPLI): A Clinical Point of View on a Promising Strategy to Improve Liver Regeneration

The capacity of the liver to regenerate is an important clinical issue after major hepatectomies and makes the difference between life and death in some cases of post-operative malfunction when the liver remnant is too small or has an impaired regenerative capacity. Several approaches have been tested to stimulate hepatic regeneration after post-operative hepatic failure syndrome; however, they have produced controversial results. A quick, simple, and harmless method that can be used intraoperatively and capable of promoting an increased regenerative capacity of the remaining liver would be very welcome. Thus, based on the data in the literature, we presented low-power laser irradiation (LPLI) as a quick, simple, and harmless method to improve liver regeneration after major hepatectomies. This article highlights the current evidence about the effects of LPLI on liver regeneration, and also suggests laser therapy as an important tool for regenerative stimulation in clinical practice.

Safe Resection of Renal Cell Carcinoma with Liver Invasion Using Liver Hanging Technique Supported by Preoperative Portal Vein Embolization

In cases of RCC with liver involvement, partial hepatectomy is known to provide a better chance of survival for patients. For this reason, complete resection with clear surgical margin is thought to be necessary to achieve favorable outcome. Anterior liver hanging maneuver was extremely useful during hemihepatectomy in this rare type of RCC. A 63-year-old male was diagnosed with a large right renal cell carcinoma. The tumor measured 10 cm in diameter with tumor thrombus toward the inferior vena cava (IVC). In addition, we observed direct infiltration to the liver. We attempted a preoperative portal vein embolization (PVE) to preserve residual liver volume and function after right lobectomy. After PVE the resected volume decreased from 921 cm³ (71%) to 599 cm³ (53.4%). During the procedure, a nasogastric tube was placed in the retrohepatic space for liver hanging maneuver according to the original Belghiti's maneuver after dissection of the renal artery and vein. After hepatic parenchymal transection exposing vena cava, the right hepatic veins were safely transected using vascular stapler; right nephrectomy and hemihepatectomy were performed. The patient recovered without postoperative hepatic or urinary complications and has remained free of local recurrence and any de novo metastasis for 18 months.

The outcomes of central hepatectomy versus extended hepatectomy: a systematic review and meta-analysis

BACKGROUND

Central hepatectomy (CH) is a relatively uncommon liver resection technique. It is generally perceived as a more complex operation than extended hepatectomies (EH), with potentially higher associated morbidity. The outcomes of CH compared with EH is not well defined and there is a need to reassess.

METHODS

A systematic literature search was conducted in PubMed, MEDLINE, EMBASE and Web of Science according to PRISMA guidelines for studies on the treatment of liver tumours with CH published from 1972 until February 2017. Outcomes of patients undergoing CH were assessed and compared to those undergoing EH.

RESULTS

18 publications including 1380 CH were included for analysis. Mortality rates after CH ranged from 0 to 9%. There were 20 (1.4%) deaths after CH and the most common cause of death was post-hepatectomy liver failure (PHLF). Morbidity rates varied between 12 and 61% and 316 (23%) post-operative events were reported. Analysis of five comparative studies showed similar mortality between CH and EH groups (OR: 0.64, 95% CI = 0.24-1.70, p = 0.37). There were significantly fewer overall post-operative complications in the CH group (OR: 0.38, 95% CI = 0.28-0.51, p < 0.001) and reduced PHLF was found in the CH group compared to EH (OR: 0.53, 95% CI = 0.29-0.98, p = 0.04). The rates of post-hepatectomy biliary complications were similar between groups (OR: 0.98, 95% CI = 0.51-1.88, p = 0.96). Mean length of stay (days) was shorter in the CH group (MD: -2.67, 95% CI = -4.93 to -0.41, p = 0.02).

CONCLUSION

CH appears to have similar post-operative mortality rates compared to EH but is associated with fewer post-operative complications, including PHLF and shorter overall length of stay.

Liver segmentation: indications, techniques and future directions

OBJECTIVES

Liver volumetry has emerged as an important tool in clinical practice. Liver volume is assessed primarily via organ segmentation of computed tomography (CT) and magnetic resonance imaging (MRI) images. The goal of this paper is to provide an accessible overview of liver segmentation targeted at radiologists and other healthcare professionals.

METHODS

Using images from CT and MRI, this paper reviews the indications for liver segmentation, technical approaches used in segmentation software and the developing roles of liver segmentation in clinical practice.

RESULTS

Liver segmentation for volumetric assessment is indicated prior to major hepatectomy, portal vein embolisation, associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) and transplant. Segmentation software can be categorised according to amount of user input involved: manual, semi-automated and fully automated. Manual segmentation is considered the "gold standard" in clinical practice and research, but is tedious and time-consuming. Increasingly automated segmentation approaches are more robust, but may suffer from certain segmentation pitfalls. Emerging applications of segmentation include surgical planning and integration with MRI-based biomarkers.

CONCLUSIONS

Liver segmentation has multiple clinical applications and is expanding in scope. Clinicians can employ semi-automated or fully automated segmentation options to more efficiently integrate volumetry into clinical practice.

TEACHING POINTS

• Liver volume is assessed via organ segmentation on CT and MRI examinations. • Liver segmentation is used for volume assessment prior to major hepatic procedures. • Segmentation approaches may be categorised according to the amount of user input involved. • Emerging applications include surgical planning and integration with MRI-based biomarkers.

Establishing a Porcine Model of Small for Size Syndrome following Liver Resection

BACKGROUND

Small for size syndrome (SFSS) is responsible for a high proportion of mortalities and morbidities following extended liver resection.

AIM

The aim of this study was to establish a porcine model of SFSS.

METHODS

Twenty-four Landrace pigs underwent liver resection with a remnant liver volume of 50% (group A, n = 8), 25% (group B, n = 8), and 15% (group C, n = 8). After resection, the animals were followed up for 8 days and clinical, laboratory, and histopathological outcomes were evaluated.

RESULTS

The survival rate was significantly lower in group C compared with the other groups (p < 0.001). The international normalized ratio, bilirubin, aspartate transaminase, alanine transaminase, and alkaline phosphatase levels increased shortly after surgery in groups B and C, but no change was observed in group A (p < 0.05 for all analyses). The histopathological findings in group A were mainly mild mitoses, in group B severe mitoses and hepatocyte ballooning, moderate congestion, and hemorrhage, along with mild necrosis, and in group C extended tissue damage with severe necrosis, hemorrhage, and congestion.

CONCLUSIONS

Combination of clinical, laboratory, and histopathological evaluations is needed to confirm the diagnosis of SFSS. 75% liver resection in porcine model results in SFSS. 85% liver resection causes irreversible liver failure.

Preliminary study on liver function changes after trisectionectomy with versus without prior portal vein embolization

PURPOSE

Post-hepatectomy liver failure (PHLF) is the major risk factor for mortality after hepatectomy. Preoperative planning of the future liver remnant volume reduces PHLF rates; however, future liver remnant function (FLR-F) might have an even stronger predictive value. In this preliminary study, we used a new method to calculate FLR-F by the LiMAx test and computer tomography-assisted volumetric-analysis to visualize liver function changes after portal vein embolization (PVE) before extended hepatectomy.

METHODS

The subjects included patients undergoing extended right hepatectomy either directly (NO-PVE group) or after PVE (PVE group). Computed tomography (CT) scan and liver function tests (LiMAx) were done before PVE and preoperatively. FLR-F was calculated and correlated with the postoperative liver function.

RESULTS

There were 12 patients in the NO-PVE group and 19 patients in the PVE group. FLR-F and postoperative liver function correlated significantly in both groups (p = 0.036, p = 0.011), although postoperative liver function was slightly overestimated, at 32 and 45 µg/kg/min, in the NO-PVE and PVE groups, respectively. LiMAx value did not change after PVE.

CONCLUSIONS

Volume-function analysis using LiMAx and CT scan enables us to reliably predict early postoperative liver function. Global enzymatic liver function measured by the LiMAx test did not change after PVE, confirming that liver function distribution in the liver stays constant after PVE. An overestimation of FLR-F is needed to compensate for the intraoperative liver injury that occurs in patients undergoing extended hepatectomy.

Portal vein embolization with plug/coils improves hepatectomy outcome

BACKGROUND

Portal vein embolization (PVE) has become the standard of care before extended hepatectomy. Various PVE methods using different embolization materials have been described. In this study, we compared PVE with polyvinyl alcohol particles alone (PVA only) versus PVA with plug or coils (PVA + plug/coils).

MATERIALS AND METHODS

Patients undergoing PVE before hepatectomy were included. PVA alone was used until December 2013, thereafter plug or coils were placed in addition. The volume of left lateral liver lobe (LLL), clinical parameters, and liver function tests were measured before PVE and resection.

RESULTS

A total of 43 patients were recruited into the PVA only group and 42 were recruited into the PVA + plug/coils group. There were no major differences between groups except significantly higher total bilirubin level before PVE in the PVA only group, which improved before hepatectomy. Mean LLL volume increased by 25.7% after PVE in the PVA only group and by 44% in the PVA + plug/coils group (P < 0.001). Recanalization was significantly less common in the PVA + plug/coils group. In multivariate regression, initial LLL volume and use of plug or coils were the only parameters influencing LLL volume increase. The postoperative liver failure rate was significantly reduced in PVA + plug/coils group (P = <0.001).

CONCLUSIONS

PVE using PVA particles together with plug or coils is a safe and efficient method to increase future liver remnant volume. The additional central embolization with plug or coils led to an increased hypertrophy, due to lower recanalization rates, and subsequently decreased incidence of postoperative liver failure. No additional procedure-specific complications were observed in this series.