What Is Hot and New in Basic and Translational Science in Liver Transplantation in 2023? Report of the Basic and Translational Research Committee of the International Liver Transplantation Society

The 2023 Joint Annual Congress of the International Liver Transplantation Society, European Liver and Intestine Transplant Association, and Liver Intensive Care Group of Europe were held in Rotterdam, the Netherlands, from May 3 to 6, 2023. This year, all speakers were invited to attend the Congress in person for the first time since the COVID-19 pandemic. The congress was attended by 1159 registered delegates from 54 countries representing 5 continents, with the 10 countries comprising the bulk of the delegates. Of the 647 abstracts initially submitted, 542 were eventually presented at the meeting, coming from 38 countries (mainly North America, Europe, and Asia) and 85% of them (462 abstracts) came from only 10 countries. Fifty-three (9.8%) abstracts, originated from 17 countries, were submitted under the Basic/Translational Scientific Research category, a similar percentage as in 2022. Abstracts presented at the meeting were classified as (1) ischemia and reperfusion injury, (2) machine perfusion, (3) bioengineering and liver regeneration, (4) transplant oncology, (5) novel biomarkers in liver transplantation, (6) liver immunology (rejection and tolerance), and (7) artificial intelligence and machine learning. Finally, we evaluated the number of abstracts commented in the Basic and Translational Research Committee-International Liver Transplantation Society annual reports over the past 5 y that resulted in publications in peer-reviewed journals to measure their scientific impact in the field of liver transplantation.

Clinical Research in Renal Transplantation: A Bibliometric Perspective on a Half-century of Innovation and Progress

BACKGROUND

Groundbreaking biomedical research has transformed renal transplantation (RT) into a widespread clinical procedure that represents the mainstay of treatment for end-stage kidney failure today. Here, we aimed to provide a comprehensive bibliometric perspective on the last half-century of innovation in clinical RT.

METHODS

The Web of Science Core Collection was used for a comprehensive screening yielding 123 303 research items during a 50-y period (January 1973-October 2022). The final data set of the 200 most-cited articles was selected on the basis of a citation-based strategy aiming to minimize bias.

RESULTS

Studies on clinical and immunological outcomes (n = 63 and 48), registry-based epi research (n = 38), and randomized controlled trials (n = 35) dominated the data set. Lead US authors have signed 110 of 200 articles. The overall level of evidence was high, with 84% of level1 and -2 reports. Highest numbers of these articles were published in New England Journal of Medicine , Transplantation , and American Journal of Transplantation. Increasing trend was observed in the number of female authors in the postmillennial era (26% versus 7%).

CONCLUSIONS

This study highlights important trends in RT research of the past half-century. This bibliometric perspective identifies the most intensively researched areas and shift of research interests over time; however, it also describes important imbalances in distribution of academic prolificacy based on topic, geographical aspects, and gender.

Shining a spotlight on sarcopenia and myosteatosis in liver disease and liver transplantation: Potentially modifiable risk factors with major clinical impact

Muscle-wasting and disease-related malnutrition are highly prevalent in patients with chronic liver diseases (CLD) as well as in liver transplant (LT) candidates. Alterations of body composition (BC) such as sarcopenia, myosteatosis and sarcopenic obesity and associated clinical frailty were tied to inferior clinical outcomes including hospital admissions, length of stay, complications, mortality and healthcare costs in various patient cohorts and clinical scenarios. In contrast to other inherent detrimental individual characteristics often observed in these complex patients, such as comorbidities or genetic risk, alterations of the skeletal muscle and malnutrition are considered as potentially modifiable risk factors with a major clinical impact. Even so, there is only limited high-level evidence to show how these pathologies should be addressed in the clinical setting. This review discusses the current state-of-the-art on the role of BC assessment in clinical outcomes in the setting of CLD and LT focusing mainly on sarcopenia and myosteatosis. We focus on the disease-related pathophysiology of BC alterations. Based on these, we address potential therapeutic interventions including nutritional regimens, physical activity, hormone and targeted therapies. In addition to summarizing existing knowledge, this review highlights novel trends, and future perspectives and identifies persisting challenges in addressing BC pathologies in a holistic way, aiming to improve outcomes and quality of life of patients with CLD awaiting or undergoing LT.

Machine perfusion of the liver and in vivo animal models: A systematic review of the preclinical research landscape

Machine perfusion (MP) is often referred to as one of the most promising advancements in liver transplantation research of the last few decades, with various techniques and modalities being evaluated in preclinical studies using animal models. However, low scientific rigor and subpar reporting standards lead to limited reproducibility and translational potential, hindering progress. This pre-registered systematic review (PROSPERO: CRD42021234667) aimed to provide a thematic overview of the preclinical research landscape on MP in liver transplantation using in vivo transplantation models and to explore methodological and reporting standards, using the ARRIVE (Animal Research: Reporting of In Vivo Experiments) score. In total 56 articles were included. Studies were evenly distributed across Asia, Europe, and the Americas. Porcine models were used in 57.1% of the studies, followed by rats (39.3%) and dogs (3.6%). In terms of graft type, 55.4% of the studies used donation after cardiac death grafts, while donation after brain death grafts accounted for 37.5%. Regarding MP modalities, the distribution was as follows: 41.5% of articles utilized hypothermic MP, 21.5% normothermic MP, 13.8% subnormothermic MP, and 16.9% utilized hypothermic oxygenated MP. The stringent documentation of ARRIVE elements concerning precise experimental execution, group size and selection, the choice of statistical methods, as well as adherence to the principles of the 3Rs, was notably lacking in the majority of publications, with less than 30% providing comprehensive details. Postoperative analgesia and antibiotics treatment were not documented in 82.1% of all included studies. None of the analyzed studies fully adhered to the ARRIVE Guidelines. In conclusion, the present study emphasizes the importance of adhering to reporting standards to promote reproducibility and adequate animal welfare in preclinical studies in machine perfusion. At the same time, it highlights a clear deficiency in this field, underscoring the need for further investigations into animal welfare-related topics.

Detrimental impact of immunosuppressive burden on clinical course in patients with Cytomegalovirus infection after liver transplantation

INTRODUCTION

Cytomegalovirus (CMV)-infection and reactivation remain a relevant complication after liver transplantation (LT). The recipient and donor serum CMV-IgG-status has been established for risk stratification when choosing various pharmaceutical regimens for CMV-prophylaxis in the last two decades. However, factors influencing course of CMV-infection in LT remain largely unknown. In this study, the impact of immunosuppressive regimen was examined in a large cohort of patients.

METHODS

All patients that underwent primary LT between 2006 and 2018 at the Charité-Universitaetsmedizin, Berlin, were included. Clinical course as well as histological and laboratory findings of patients were analyzed our prospectively maintained database. Univariate and multivariate regression analysis for impact of variables on CMV-occurrence was conducted, and survival was examined using Kaplan-Meier analysis.

RESULTS

Overall, 867 patients were included in the final analysis. CMV-infection was diagnosed in 325 (37.5%) patients after transplantation. Significantly improved overall survival was observed in these patients (Log rank = 0.03). As shown by correlation and regression tree classification and regression tree analysis, the recipient/donor CMV-IgG-status with either positivity had the largest influence on CMV-occurrence. Analysis of immunosuppressive burden did not reveal statistical impact on CMV-infection, but statistically significant inverse correlation of cumulative tacrolimus trough levels and survival was found (Log rank < .001). Multivariate analysis confirmed these findings (p = .02).

DISCUSSION

CMV-infection remains of clinical importance after LT. Undergone CMV-infection of either recipient or donor requires prophylactic treatment. Additionally, we found a highly significant, dosage-dependent impact of immunosuppression (IS) on long-term outcomes for these patients, underlying the importance of minimization of IS in liver transplant recipients.

Improved outcomes after hypothermic oxygenated machine perfusion in liver transplantation-Long-term follow-up of a multicenter randomized controlled trial

BACKGROUND

While 4 randomized controlled clinical trials confirmed the early benefits of hypothermic oxygenated machine perfusion (HOPE), high-level evidence regarding long-term clinical outcomes is lacking. The aim of this follow-up study from the HOPE-ECD-DBD trial was to compare long-term outcomes in patients who underwent liver transplantation using extended criteria donor allografts from donation after brain death (ECD-DBD), randomized to either HOPE or static cold storage (SCS).

METHODS

Between September 2017 and September 2020, recipients of liver transplantation from 4 European centers receiving extended criteria donor-donation after brain death allografts were randomly assigned to HOPE or SCS (1:1). Follow-up data were available for all patients. Analyzed endpoints included the incidence of late-onset complications (occurring later than 6 months and graded according to the Clavien-Dindo Classification and the Comprehensive Complication Index) and long-term graft survival and patient survival.

RESULTS

A total of 46 patients were randomized, 23 in both arms. The median follow-up was 48 months (95% CI: 41-55). After excluding early perioperative morbidity, a significant reduction in late-onset morbidity was observed in the HOPE group (median reduction of 23 Comprehensive Complication Index-points [p=0.003] and lower incidence of major complications [Clavien-Dindo ≥3, 43% vs. 85%, p=0.009]). Primary graft loss occurred in 13 patients (HOPE n=3 vs. SCS n=10), resulting in a significantly lower overall graft survival (p=0.029) and adverse 1-, 3-, and 5-year survival probabilities in the SCS group, which did not reach the level of significance (HOPE 0.913, 0.869, 0.869 vs. SCS 0.783, 0.606, 0.519, respectively).

CONCLUSIONS

Our exploratory findings indicate that HOPE reduces late-onset morbidity and improves long-term graft survival providing clinical evidence to further support the broad implementation of HOPE in human liver transplantation.

Value of prognostic scoring systems in the era of multimodal therapy for recurrent colorectal liver metastases

BACKGROUND

Various predictive scoring systems have been developed to estimate outcomes of patients undergoing surgery for colorectal liver metastases (CRLM). However, data regarding their effectiveness in recurrent CRLM (recCRLM) are very limited.

METHODS

Patients who underwent repeat hepatectomy for recCRLM at the University Hospital RWTH Aachen, Germany from 2010 to 2021 were included. Nine predictive scoring systems (Fong's, Nordlinger, Nagashima, RAS mutation, Tumor Burden, GAME, CERR, and Glasgow Prognostic score, Basingstoke Index) were evaluated by likelihood ratio (LR) χ2, linear trend (LT) χ2 and Akaike Information Criterion (AIC) for their predictive value regarding overall survival (OS) and recurrence free survival (RFS).

RESULTS

Among 150 patients, median RFS was 9 (2-124) months with a 5-year RFS rate of 10%. Median OS was 39 (4-131) months with a 5-year OS rate of 32%. For RFS and OS, the Nagashima score showed the best prognostic ability (LT χ2 3.00, LR χ2 9.39, AIC 266.66 and LT χ2 2.91, LR χ2 20.91, 290.36).

DISCUSSION

The Nagashima score showed the best prognostic stratification to predict recurrence as well as survival, and therefore might be considered when evaluating patients with recCRLM for repeat hepatectomy.

Genetic polymorphisms in interleukin-1β (rs1143634) and interleukin-8 (rs4073) are associated with survival after resection of intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA) is a rare, understudied primary hepatic malignancy with dismal outcomes. Aiming to identify prognostically relevant single-nucleotide polymorphisms, we analyzed 11 genetic variants with a role in tumor-promoting inflammation (VEGF, EGF, EGFR, IL-1B, IL-6, CXCL8 (IL-8), IL-10, CXCR1, HIF1A and PTGS2 (COX-2) genes) and their association with disease-free (DFS) and overall survival (OS) in patients undergoing curative-intent surgery for iCCA. Genomic DNA was isolated from 112 patients (64 female, 48 male) with iCCA. Germline polymorphisms were analyzed with polymerase chain reaction-restriction fragment length polymorphism protocols. The IL-1B +3954 C/C (73/112, hazard ratio (HR) = 1.735, p = 0.012) and the IL-8 -251 T/A or A/A (53/112 and 16/112, HR = 2.001 and 1.1777, p = 0.026) genotypes were associated with shorter OS in univariable and multivariable analysis. The IL-1B +3954 polymorphism was also associated with shorter DFS (HR = 1.983, p = 0.012), but this effect was not sustained in the multivariable model. A genetic risk model of 0, 1 and 2 unfavorable alleles was established and confirmed in multivariable analysis. This study supports the prognostic role of the IL-1B C+3954T and the IL-8 T-251A variant as outcome markers in iCCA patients, identifying patient subgroups at higher risk for dismal clinical outcomes.

Implementation of the Surgical Apgar Score in Laboratory Animal Science: A Showcase Pilot Study in a Porcine Model and a Review of the Literature

INTRODUCTION

In an attempt to further improve surgical outcomes, a variety of outcome prediction and risk-assessment tools have been developed for the clinical setting. Risk scores such as the surgical Apgar score (SAS) hold promise to facilitate the objective assessment of perioperative risk related to comorbidities of the patients or the individual characteristics of the surgical procedure itself. Despite the large number of scoring models in clinical surgery, only very few of these models have ever been utilized in the setting of laboratory animal science. The SAS has been validated in various clinical surgical procedures and shown to be strongly associated with postoperative morbidity. In the present study, we aimed to review the clinical evidence supporting the use of the SAS system and performed a showcase pilot trial in a large animal model as the first implementation of a porcine-adapted SAS (pSAS) in an in vivo laboratory animal science setting.

METHODS

A literature review was performed in the PubMed and Embase databases. Study characteristics and results using the SAS were reported. For the in vivo study, 21 female German landrace pigs have been used either to study bleeding analogy (n = 9) or to apply pSAS after abdominal surgery in a kidney transplant model (n = 12). The SAS was calculated using 3 criteria: (1) estimated blood loss during surgery; (2) lowest mean arterial blood pressure; and (3) lowest heart rate.

RESULTS

The SAS has been verified to be an effective tool in numerous clinical studies of abdominal surgery, regardless of specialization confirming independence on the type of surgical field or the choice of surgery. Thresholds for blood loss assessment were species specifically adjusted to >700 mL = score 0; 700-400 mL = score 1; 400-55 mL score 2; and <55 mL = score 3 resulting in a species-specific pSAS for a more precise classification.

CONCLUSION

Our literature review demonstrates the feasibility and excellent performance of the SAS in various clinical settings. Within this pilot study, we could demonstrate the usefulness of the modified SAS (pSAS) in a porcine kidney transplantation model. The SAS has a potential to facilitate early veterinary intervention and drive the perioperative care in large animal models exemplified in a case study using pigs. Further larger studies are warranted to validate our findings.

Body composition and the skeletal muscle compartment in liver transplantation: Turning challenges into opportunities

Frailty, nutritional status, and body composition are increasingly under the spotlight of interest in various clinical scenarios including liver transplantation. To address the rapidly accumulating evidence in this field, recent European and North American practice guidelines have clearly underlined the clinical importance of nutritional status and body composition with adopting their assessment in patients with liver disease and in transplant candidates into their recommendations. While earlier reports, and therefore present guidelines, were focusing predominantly on quantitative alterations of the skeletal muscle mass (sarcopenia), recent studies have identified qualitative alterations such as intramuscular fat accumulation (myosteatosis) and sarcopenic obesity as emerging risk factors for poor clinical outcomes. In this review, the role of body composition in the context of liver transplantation will be discussed with a focus on the skeletal muscle compartment. A brief overview of current assessment modalities including their limitations, diagnostic challenges, prognostic significance, and pathophysiology are included. Possibilities to incorporate body composition parameters into clinical decision making are discussed. In addition, novel trends and remaining challenges in the therapeutic targeting of body composition and the skeletal muscle compartment are highlighted.

The prognostic value of neutrophil-to-lymphocyte ratio in cholangiocarcinoma: a systematic review and meta-analysis

The neutrophil-to-lymphocyte ratio (NLR) is used as biomarker in malignant diseases showing significant association with poor oncological outcomes. The main research question of the present study was whether NLR has also prognostic value in cholangiocarcinoma patients (CCA). A systematic review was carried out to identify studies related to NLR and clinical outcomes in CCA evaluating the literature from 01/2000 to 09/2021. A random-effects model, pooled hazard ratios (HR) and 95% confidence interval (CI) were used to investigate the statistical association between NLR and overall survival (OS) as well as disease-free survival (DFS). Subgroup analyses, evaluation of sensitivity and risk of bias were further carried out. 32 studies comprising 8572 patients were eligible for this systematic review and meta-analysis. The pooled outcomes revealed that high NLR prior to treatment is prognostic for poor OS (HR 1.28, 95% CI 1.18–1.38, p < 0.01) and DFS (HR 1.39, 95% CI 1.17–1.66, p < 0.01) with meaningful HR values. Subgroup analysis revealed that this association is not significantly affected by the treatment modality (surgical vs. non-surgical), NLR cut-off values, age and sample size of the included studies. Given the likelihood of NLR to be prognostic for reduced OS and DFS, pre-treatment NLR might serve as a useful biomarker for poor prognosis in patients with CCA and therefore facilitate clinical management.

Perioperative and long-term outcome of en-bloc arterial resection in pancreatic surgery

BACKGROUND

Pancreatic tumors are frequently diagnosed in a locally advanced stage with poor prognosis if untreated. This study assesses the safety and oncological outcomes of pancreatic surgery with arterial en-bloc resection.

METHODS

We retrospectively reviewed a prospectively maintained database of patients who underwent a pancreatic resection with arterial resection between 2011 and 2020. Univariable analyses were used to assess prognostic factors for survival.

RESULTS

Forty consecutive patients (22 female; 18 male) undergoing arterial resections were included. Surgical procedures consisted of 19 pancreatoduodenectomies (PD, 48%), 16 distal splenopancreatectomy (DSP, 40%), and 5 total pancreatectomies (TP, 12%). Arterial resection included hepatic arteries (HA, N = 23), coeliac trunk (TC, N = 15) and superior mesenteric artery (SMA, N = 2). Neoadjuvant therapy was applied in 22 patients (58%). Major complications after surgery were observed in 15% of cases. 90-day mortality was 5%. Median disease-free survival and median overall survival were for the R0/CRM- group 22.8 months and 27.9 months, 9.5 and 19.8 months for the R0/CRM+ group, and 10.1 and 13.1 months for the R1 group, respectively.

CONCLUSION

In highly selected patients, arterial en-bloc resection can be performed with acceptable mortality and morbidity rates and beneficial oncological outcome.

Prognostic Factors for Mortality in Acute Mesenteric Ischemia

Postoperative mortality in patients undergoing surgical and/or interventional treatment for acute mesenteric ischemia (AMI) has remained an unsolved problem in recent decades. Here, we investigated clinical predictors of postoperative mortality in a large European cohort of patients undergoing treatment for AMI. In total, 179 patients who underwent surgical and/or interventional treatment for AMI between 2009 and 2021 at our institution were included in this analysis. Associations between postoperative mortality and various clinical variables were assessed using univariate and multivariable binary logistic regression analysis. Most of the patients were diagnosed with arterial ischemia (AI; n = 104), while venous ischemia (VI; n = 21) and non-occlusive mesenteric ischemia (NOMI; n = 54) were present in a subset of patients. Overall inhouse mortality was 55.9% (100/179). Multivariable analyses identified leukocytes (HR = 1.08; p = 0.008), lactate (HR = 1.25; p = 0.01), bilirubin (HR = 2.05; p = 0.045), creatinine (HR = 1.48; p = 0.039), etiology (AI, VI or NOMI; p = 0.038) and portomesenteric vein gas (PMVG; HR = 23.02; p = 0.012) as independent predictors of postoperative mortality. In a subanalysis excluding patients with fatal prognosis at the first surgical exploration (n = 24), leukocytes (HR = 1.09; p = 0.004), lactate (HR = 1.27; p = 0.003), etiology (AI, VI or NOMI; p = 0.006), PMVG (HR = 17.02; p = 0.018) and intraoperative FFP transfusion (HR = 4.4; p = 0.025) were determined as independent predictors of postoperative mortality. Further, the risk of fatal outcome changed disproportionally with increased preoperative lactate values. The clinical outcome of patients with AMI was determined using a combination of pre- and intraoperative clinical and radiological characteristics. Serum lactate appears to be of major clinical importance as the risk of fatal outcome increases significantly with higher lactate values.

The prognostic impact of preoperative body composition in perihilar and intrahepatic cholangiocarcinoma

Cholangiocarcinoma (CCA) is a rare but highly aggressive malignancy of the biliary system. Although it is amenable to surgical resection in early disease, outcomes are frequently dismal. Here, we investigated the prevalence of body composition (BC) alterations and their prognostic role for surgical patients with intrahepatic (iCCA) and perihilar (pCCA) disease. Patients undergoing curative‐intent surgery for iCCA or pCCA between 2010 and 2019 at University Hospital Aachen were included. Axial computed tomography images were retrospectively assessed with a segmentation tool (3D Slicer) at the level of the third lumbar vertebra to determine lumbar skeletal muscle (SM) index, mean SM radiation attenuation, and visceral fat area. The related BC pathologies sarcopenia, myosteatosis, visceral obesity, and sarcopenic obesity were determined using previously described cutoffs. A total of 189 patients (86 with iCCA, 103 with pCCA) were included. Alterations of BC were highly prevalent in iCCA and pCCA, respectively: sarcopenia, 33% (28/86) and 39% (40/103); myosteatosis, 66% (57/86) and 66% (68/103); visceral obesity, 56% (48/86) and 67% (69/103); sarcopenic obesity, 11% (9/86) and 17% (17/103). Sarcopenia and myosteatosis did not have a significant prognostic role for disease‐free survival (DFS) and overall survival (OS). Patients with iCCA with sarcopenic obesity (n = 9) had significantly shorter OS than patients without sarcopenic obesity (n = 7; log‐rank p = 0.002; median OS, 11 months and 31 months; 1‐year mortality, 55.6% [5/9] and 22% [17/77]; 5‐year mortality, 88.9% [8/9] and 61% [47/77], respectively). In multivariable analysis, only tumor‐related risk factors remained prognostic for DFS and OS. Sarcopenic obesity may affect clinical outcomes after curative‐intent surgery for iCCA, indicating that imaging‐based analysis of BC may hold prognostic value for long‐term survival and could aid preoperative patient selection.

The role of re-resection in recurrent hepatocellular carcinoma

Purpose

While liver resection is a well-established treatment for primary HCC, surgical treatment for recurrent HCC (rHCC) remains the topic of an ongoing debate. Thus, we investigated perioperative and long-term outcome in patients undergoing re-resection for rHCC in comparative analysis to patients with primary HCC treated by resection.

Methods

A monocentric cohort of 212 patients undergoing curative-intent liver resection for HCC between 2010 and 2020 in a large German hepatobiliary center were eligible for analysis. Patients with primary HCC (n = 189) were compared to individuals with rHCC (n = 23) regarding perioperative results by statistical group comparisons and oncological outcome using Kaplan–Meier analysis.

Results

Comparative analysis showed no statistical difference between the resection and re-resection group in terms of age (p = 0.204), gender (p = 0.180), ASA category (p = 0.346) as well as main preoperative tumor characteristics, liver function parameters, operative variables, and postoperative complications (p = 0.851). The perioperative morbidity (Clavien-Dindo ≥ 3a) and mortality were 21.7% (5/23) and 8.7% (2/23) in rHCC, while 25.4% (48/189) and 5.8% (11/189) in primary HCC, respectively (p = 0.851). The median overall survival (OS) and recurrence-free survival (RFS) in the resection group were 40 months and 26 months, while median OS and RFS were 41 months and 29 months in the re-resection group, respectively (p = 0.933; p = 0.607; log rank).

Conclusion

Re-resection is technically feasible and safe in patients with rHCC. Further, comparative analysis displayed similar oncological outcome in patients with primary and rHCC treated by liver resection. Re-resection should therefore be considered in European patients diagnosed with rHCC.

PD-1+ T-Cells Correlate with Nerve Fiber Density as a Prognostic Biomarker in Patients with Resected Perihilar Cholangiocarcinoma

Simple Summary

Recent studies have identified Nerve Fiber Density (NFD) as a prognostic biomarker for Cholangiocarcinoma (CCA). In the field of CCA treatment with checkpoint inhibitors (ICI) is increasing but not all patients respond. Good biomarkers to predict response to ICI are lacking. The present study investigates the immune cell composition and expression of checkpoint molecules in relation to NFD in perihilar cholangiocarcinoma (pCCA) patients. Our study identified NFD to correlate with PD-1+ T cells as a biomarker indicative for a good prognosis.

Abstract

Background and Aims: Perihilar cholangiocarcinoma (pCCA) is a hepatobiliary malignancy, with a dismal prognosis. Nerve fiber density (NFD)—a novel prognostic biomarker—describes the density of small nerve fibers without cancer invasion and is categorized into high numbers and low numbers of small nerve fibers (high vs low NFD). NFD is different than perineural invasion (PNI), defined as nerve fiber trunks invaded by cancer cells. Here, we aim to explore differences in immune cell populations and survival between high and low NFD patients. Approach and Results: We applied multiplex immunofluorescence (mIF) on 47 pCCA patients and investigated immune cell composition in the tumor microenvironment (TME) of high and low NFD. Group comparison and oncological outcome analysis was performed. CD8+PD-1 expression was higher in the high NFD than in the low NFD group (12.24 × 10⁻⁶ vs. 1.38 × 10⁻⁶ positive cells by overall cell count, p = 0.017). High CD8+PD-1 expression was further identified as an independent predictor of overall (OS; Hazard ratio (HR) = 0.41; p = 0.031) and recurrence-free survival (RFS; HR = 0.40; p = 0.039). Correspondingly, the median OS was 83 months (95% confidence interval (CI): 18–48) in patients with high CD8+PD-1+ expression compared to 19 months (95% CI: 5–93) in patients with low CD8+PD-1+ expression (p = 0.018 log rank). Furthermore, RFS was significantly lower in patients with low CD8+PD-1+ expression (14 months (95% CI: 6–22)) compared to patients with high CD8+PD-1+ expression (83 months (95% CI: 17–149), p = 0.018 log rank). Conclusions: PD-1+ T-cells correlate with high NFD as a prognostic biomarker and predict good survival; the biological pathway needs to be investigated.

Bowel Obstruction Due to Stenotic Sigmoid Colon Cancer in a 32-Year-Old Patient Presenting in the Third Trimester of Pregnancy: A Case Report of an Interval Surgical Approach

Patient: Female, 32-year-old

Final Diagnosis: Colon adenocarcinoma

Symptoms: Ileus

Medication: —

Clinical Procedure: —

Specialty: Obstetrics and Gynecology • Surgery

The role of tumor-infiltrating lymphocytes in cholangiocarcinoma

Cholangiocarcinoma (CCA) is the second most common primary liver cancer and associated with a dismal prognosis due to the lack of an efficient systemic therapy. In contrast to other cancers, new immunotherapies have demonstrated unsatisfactory results in clinical trials, underlining the importance of a deeper understanding of the special tumor microenvironment of CCA and the role of immune cells interacting with the tumor. Tumor-infiltrating lymphocytes (TILs) are an important component of the adaptive immune system and the foundation of current immunotherapy. Therefore, the aim of this systemic review is to summarize the current literature focusing on the proportions and distribution, molecular pathogenesis, prognostic significance of TILs and their role in immunotherapy for CCA patients.

In CCA, CD8+ and CD4+ T lymphocytes represent the majority of TILs and are mostly sequestered around the cancer cells. CD20+ B lymphocytes and Natural Killer (NK) cells are less frequent. In contrast, Foxp3+ cells (regulatory T cells, Tregs) are observed to infiltrate into the tumor. In the immune microenvironment of CCA, cancer cells and stromal cells such as TAMs, TANs, MSDCs and CAFs inhibit the immune protection function of TILs by secreting factors like IL-10 and TGF-β. With respect to molecular pathogenesis, the Wnt/-catenin, TGF-signaling routes, aPKC-i/P-Sp1/Snail Signaling, B7-H1/PD-1Pathway and Fas/FasL signaling pathways are connected to the malignant potential and contributed to tumor immune evasion by increasing TIL apoptosis. Distinct subtypes of TILs show different prognostic implications for the long-term outcome in CCA. Although there are occasionally conflicting results, CD8+ and CD4+ T cells, and CD20+ B cells are positively correlated with the oncological prognosis of CCA, while a high number of Tregs is very likely associated with worse overall survival. TILs also play a major role in immunotherapy for CCA.

In summary, the presence of TILs may represent an important marker for the prognosis and a potential target for novel therapy, but more clinical and translational

data is needed to fully unravel the importance of TILs in the treatment of CCA.

Severity Assessment in Rats Undergoing Subarachnoid Hemorrhage Induction by Endovascular Perforation or Corresponding Sham Surgery

INTRODUCTION

Animal models for preclinical research of subarachnoid hemorrhage (SAH) are widely used as much of the pathophysiology remains unknown. However, the burden of these models inflicted on the animals is not well characterized. The European directive requires severity assessment-based allocation to categories. Up to now, the classification into predefined categories is rather subjective and often without underlying scientific knowledge. We therefore aimed at assessing the burden of rats after SAH or the corresponding sham surgery to provide a scientific assessment.

METHODS

We performed a multimodal approach, using different behavior tests, clinical and neurological scoring, and biochemical markers using the common model for SAH of intracranial endovascular filament perforation in male Wistar rats. Up to 7 days after surgery, animals with SAH were compared to sham surgery and to a group receiving only anesthesia and analgesia.

RESULTS

Sham surgery (n = 15) and SAH (n = 16) animals showed an increase in the clinical score the first days after surgery, indicating clinical deterioration, while animals receiving only anesthesia without surgery (n = 5) remained unaffected. Body weight loss occurred in all groups but was more pronounced and statistically significant only after surgery. The analysis of burrowing, open field (total distance, erections), balance beam, and neuroscore showed primarily an effect of the surgery itself in sham surgery and SAH animals. Only concerning balance beam and neuroscore, a difference was visible between sham surgery and SAH. The outcome of the analysis of systemic and local inflammatory parameters and of corticosterone in blood and its metabolites in feces was only robust in animals suffering from larger bleedings. Application of principal component analysis resulted in a clear separation of sham surgery and SAH animals from their respective baseline as well as from the anesthesia-only group at days 1 and 3, with the difference between sham surgery and SAH being not significant.

DISCUSSION/CONCLUSION

To our knowledge, we are the first to publish detailed clinical score sheet data combined with advanced behavioral assessment in the endovascular perforation model for SAH in rats. The tests chosen here clearly depict an impairment of the animals within the first days after surgery and are consequently well suited for assessment of the animals' suffering in the model. A definitive classification into one of the severity categories named by the EU directive is yet pending and has to be performed in the future by including the assessment data from different neurological and nonneurological disease models.

Genetic Variant of CXCR1 (rs2234671) Associates with Clinical Outcome in Perihilar Cholangiocarcinoma

BACKGROUND

Perihilar cholangiocarcinoma (pCCA) is a rare primary liver malignancy. Even in patients amenable to surgery, outcomes are often dismal. Here, we aimed to identify prognostic markers for patient outcomes by analyzing functionally relevant single-nucleotide polymorphisms (SNPs) in genes with a role in tumor inflammation and angiogenesis. We analyzed 11 polymorphisms in the inflammation-angiogenesis axis (VEGF, EGF, EGFR, IL-1b, IL-6, CXCL8 (IL-8), IL-10, CXCR1, HIF1A, and COX2 genes) for their prediction of tumor recurrence and survival in pCCA patients undergoing surgery in a curative intent.

METHODS

Samples were obtained from 111 patients with pCCA undergoing liver resection in curative intent. DNA was extracted and analyzed using polymerase chain reaction-restriction fragment length polymorphism protocols and correlated with patients' outcomes.

RESULTS

Out of the assessed variants, only the CXCR1 (also: interleukin-8-receptor alpha - IL-8RA) +860C>G heterozygous polymorphism (rs2234671) was associated with decreased disease-free survival (DFS), cancer-specific survival (CSS), and overall survival (OS) (18/111 (16.2%), median DFS 14 months, log-rank p = 0.007; median CSS 31 months, log-rank p = 0.007; and median OS 6 months, log-rank p = 0.002), compared to the GG genotype (92/111 (82.9%), median DFS 55 months, median CSS 63 months, and median OS 33 months). In the multivariate analysis, +860C>G remained an independent prognostic factor for DFS (adjusted p = 0.008), CSS (adjusted p = 0.001), and OS (adjusted p = 0.001).

CONCLUSION

Genetic variant of CXCR1 +860C>G may serve as a molecular marker for DFS, CSS, and OS in patients undergoing curative-intent surgery for pCCA, indicating that the analysis of SNPs in genes involved in immune-mediated angiogenesis may help to identify patient subgroups at high risk for dismal oncological and overall outcome.

The prognostic role of tumor-associated unilateral portal vein occlusion in perihilar cholangiocarcinoma

BACKGROUND

While a certain degree of tumor infiltration of the portal vein is common in patients with perihilar cholangiocarcinoma (pCCA) scheduled for surgery, complete tumor-associated portal vein occlusion (PVO) is less frequently observed. Here, we analyzed the impact of PVO on perioperative and oncological outcomes in pCCA patients.

METHODS

Between 2010 and 2019, 127 patients with pCCA underwent surgery in curative intent at our department of which 17.3% (22/127) presented with PVO. Extensive group comparisons were conducted and the association of cancer-specific (CSS) and disease-free survival (DFS) with PVO and other clinico-pathological characteristics were assessed using Cox regression models.

RESULTS

Patients without PVO showed a median CSS of 65 months (3-year-CSS = 64%, 5-year-CSS = 53%) compared to 31 months (3-year-CSS = 43%, 5-year-CSS = 17%) in patients with PVO (p = 0.025 log rank). Patients with PVO did also display significant perioperative mortality (22.7%, 5/22) compared to patients without PVO (14.3%, 15/105, p = 0.323). Further, PVO (CSS: HR = 5.25, p = 0.001; DFS: HR = 5.53, p = 0.001) was identified as independent predictors of oncological outcome.

CONCLUSIONS

PVO has been identified as an important prognostic marker playing a role in inferior oncological outcome in patients with pCCA. As PVO is also associated with notable perioperative mortality, surgical therapy should be considered carefully in pCCA patients.

The prognostic role of in-hospital transfusion of fresh frozen plasma in patients with cholangiocarcinoma undergoing curative-intent liver surgery

INTRODUCTION

Major hepatectomy for perihilar and intrahepatic cholangiocarcinoma (CCA) is often associated with a significant intraoperative blood loss and the requirement for perioperative transfusion of blood products. The aim of this study was to investigate the oncological impact of fresh frozen plasma (FFP) transfusion during hospitalization in patients undergoing hepatectomy for CCA as adverse effects have been described in other malignancies.

MATERIAL AND METHODS

Patients undergoing hepatectomy for CCA from 2010 to 2019 at a single institution were eligible for this study. Survival analysis was carried out according to Kaplan-Meier and the associations of cancer-specific (CSS) and recurrence-free survival (RFS) with in-hospital application of FFP and other clinico-pathological characteristics were assessed using Cox regression models. Perioperatively deceased patients were excluded from the analysis.

RESULTS

A total of 219 CCA patients were included in this survival analysis of which 53.0% (116/219) received FFP during hospitalization. Patients receiving in-hospital FFP showed a median CCS of 33 months (3-year-CSS = 46%, 5-year-CSS = 29%) compared to 83 months (3-year-CSS = 55%, 5-year-CSS = 53%) in patients who did not receive in-hospital FFP (p = 0.006 log rank). Further, in-hospital FFP was identified as an independent predictor of oncological outcome in multivariable analysis (CSS: HR = 1.71, p = 0.016; RFS: HR = 1.89, p = 0.003).

CONCLUSION

In a large European cohort of patients, in-hospital transfusion of FFP was identified as a novel independent prognostic marker in CCA patients undergoing curative-intent liver surgery. A restrictive transfusion policy is therefore recommended to improve long-term outcome in these patients.

Perioperative rifaximin is not associated with enhanced functional and volumetric recovery after major liver resection

The objective of this randomized controlled trial (RCT) was to assess the impact of rifaximin on the course of liver function, liver regeneration and volumetric recovery in patients undergoing major hepatectomy. The ARROW trial was an investigator initiated, single-center, open-label, phase 3 RCT with two parallel treatment groups, conducted at our hepatobiliary center from 03/2016 to 07/2020. Patients undergoing major hepatectomy were eligible and randomly assigned 1:1 to receive oral rifaximin (550 mg twice daily for 7-10 or 14-21 days in case of portal vein embolization preoperatively and 7 days postoperatively) versus no intervention. Primary endpoint was the relative increase in postoperative liver function measured by LiMAx from postoperative day (POD) 4 to 7. Secondary endpoint were the course of liver function and liver volume during the study period as well as postoperative morbidity and mortality. Between 2016 and 2020, 45 patients were randomized and 35 patients (16 individuals in the rifaximin and 19 individuals in the control group) were eligible for per-protocol analysis. The study was prematurely terminated following interim analysis, due to the unlikelihood of reaching a significant primary endpoint. The median relative increase in liver function from POD 4 to POD 7 was 27% in the rifaximin group and 41% in the control group (p = 0.399). Further, no significant difference was found in terms of any other endpoints of functional liver- and volume regeneration or perioperative surgical complications following the application of rifaximin versus no intervention. Perioperative application of rifaximin has no effect on functional or volumetric regeneration after major hepatectomy (NCT02555293; EudraCT 2013-004644-28).

Liver transplantation in malignant disease

Liver transplantation for malignant disease has gained increasing attention as part of transplant oncology. Following the implementation of the Milan criteria, hepatocellular carcinoma (HCC) was the first generally accepted indication for transplantation in patients with cancer. Subsequently, more liberal criteria for HCC have been developed, and research on this topic is still ongoing. The evident success of liver transplantation for HCC has led to the attempt to extend its indication to other malignancies. Regarding perihilar cholangiocarcinoma, more and more evidence supports the use of liver transplantation, especially after neoadjuvant therapy. In addition, some data also show a benefit for selected patients with very early stage intrahepatic cholangiocarcinoma. Hepatic epithelioid hemangioendothelioma is a very rare but nonetheless established indication for liver transplantation in primary liver cancer. In contrast, patients with hepatic angiosarcoma are currently not considered to be optimal candidates. In secondary liver tumors, neuroendocrine cancer liver metastases are an accepted but comparability rare indication for liver transplantation. Recently, some evidence has been published supporting the use of liver transplantation even for colorectal liver metastases. This review summarizes the current evidence for liver transplantation for primary and secondary liver cancer.

The Presence of Small Nerve Fibers in the Tumor Microenvironment as Predictive Biomarker of Oncological Outcome Following Partial Hepatectomy for Intrahepatic Cholangiocarcinoma

Simple Summary

Nerve fibers in the microenvironment of malignant tumors have been shown to be an important prognostic factor for long-term survival in various cancer types; however, their role in intrahepatic cholangiocarcinoma remains to be determined. Therefore, the impact of nerve fibers on long-term survival was investigated in a large European cohort of patients with intrahepatic cholangiocarcinoma who were treated by curative-intent surgical resection. By univariate and multivariate statistics, the absence of nerve fibers was determined to be an independent predictor of impaired long-term survival. A group comparison between patients with and without nerve fibers showed a statically significant difference with a cancer-specific 5-year-survival of 47% in patients with nerve fibers compared to 21% in patients without nerve fibers. Thus, the presence of nerve fibers in the microenvironment of intrahepatic cholangiocarcinoma is revealed as a novel and important prognostic biomarker in these patients.

Abstract

The oncological role of the density of nerve fibers (NFs) in the tumor microenvironment (TME) in intrahepatic cholangiocarcinoma (iCCA) remains to be determined. Therefore, data of 95 iCCA patients who underwent hepatectomy between 2010 and 2019 was analyzed regarding NFs and long-term outcome. Extensive group comparisons were carried out and the association of cancer-specific survival (CSS) and recurrence-free survival (RFS) with NFs were assessed using Cox regression models. Patients with iCCA and NFs showed a median CSS of 51 months (5-year-CSS = 47%) compared to 27 months (5-year-CSS = 21%) in patients without NFs (p = 0.043 log rank). Further, NFs (hazard ratio (HR) = 0.39, p = 0.002) and N-category (HR = 2.36, p = 0.010) were identified as independent predictors of CSS. Patients with NFs and without nodal metastases displayed a mean CSS of 89 months (5-year-CSS = 62%), while patients without NFs or with nodal metastases but not both showed a median CCS of 27 months (5-year-CSS = 25%) and patients with both positive lymph nodes and without NFs showed a median CCS of 10 months (5-year-CSS = 0%, p = 0.001 log rank). NFs in the TME are, therefore, a novel and important prognostic biomarker in iCCA patients. NFs alone and in combination with nodal status is suitable to identify iCCA patients at risk of poor oncological outcomes following curative-intent surgery.

Clinical value and limitations of the preoperative C-reactive-protein-to-albumin ratio in predicting post-operative morbidity and mortality after deceased-donor liver transplantation: a retrospective single-centre study

Liver transplantation is still associated with a high risk of severe complications and post-operative mortality. This study examines the predictive value of the preoperative C-reactive-protein-to-albumin ratio (CAR) regarding perioperative morbidity and mortality in deceased-donor liver transplantation (DDLT) recipients. In total, 390 DDLT recipients between 05/2010 and 03/2020 were eligible. Predictive abilities of CAR were examined through receiver operating characteristic curve (ROC) analyses. Groups were compared using parametric and non-parametric tests as appropriate. Independent risk factors for morbidity and mortality were identified using uni- and multivariable logistic regression analyses. A good predictive ability for CAR was shown regarding perioperative morbidity (comprehensive complication index ≥75, Clavien-Dindo score ≥4a) and 12-month mortality, with an ideal cut-off of CAR = 26%. Patients with CAR>26% had significantly higher median CCI scores (60 vs. 43, P < 0.001), longer intensive care unit (ICU, 5 vs. 4 days, P < 0.001) and hospital (28 vs. 21 days, P < 0.001) stays and higher 12-month mortality rates (20% vs 6%, P < 0.001). Multivariable analyses identified CAR>26%, pre-OLT inpatient hospitalization (including ICU) and post-operative red blood cell transfusions as independent predictors of severe cumulative morbidity (CCI≥75). Preoperative CAR might be a reliable additional tool to predict perioperative morbidity and mortality in DDLT recipients.

Compelling Long-Term Results for Liver Resection in Early Cholangiocarcinoma

Surgery for intrahepatic cholangiocarcinoma (iCCA) is associated with a high rate of recurrence even after complete resection. To achieve acceptable results, preoperative patient selection is crucial. Hence, we aimed to identify preoperative characteristics with prognostic value focusing on certain radiological features. Patients who underwent hepatectomy for iCCA between 2010 and 2020 at University Hospital, RWTH Aachen were included. Kaplan–Meier and Cox regressions were applied for survival analysis and associations of overall survival (OS) and recurrence-free survival (RFS) with clinical/radiological characteristics, respectively. Based on radiological features patients were stratified into three groups: single nodule ≤ 3 cm, single nodule > 3 cm, and ≥2 nodules. Analysis of 139 patients revealed a mean OS of 142 months for those with a single nodule ≤3 cm, median OS of 28 months with a single nodule >3 cm, and 19 months with ≥2 nodules, respectively. Multivariable analyses based on preoperative characteristics showed the radiological stratification to be independently associated with OS (HR (hazard ratio) = 4.25 (1 nodule, >3 cm), HR = 5.97 (≥2 nodules), p = 0.011), RFS (HR = 4.18 (1 nodule, >3 cm), and HR = 11.07 (≥2 nodules), p = 0.001). In conclusion, patients with single iCCA ≤3 cm show compelling OS and RFS. Basic radiological features (e.g., nodule size, number) are prognostic for patients undergoing surgery and useful in preoperative patient selection.

Various myosteatosis selection criteria and their value in the assessment of short- and long-term outcomes following liver transplantation

Body composition and myosteatosis affect clinical outcomes in orthotopic liver transplantation (OLT). Here we aimed to compare the value and limitations of various selection criteria to define pre-transplant myosteatosis in the assessment of short- and long-term outcomes following OLT. We retrospectively analyzed the data of 264 consecutive recipients who underwent deceased donor OLT at a German university medical centre. Myosteatosis was evaluated by preoperative computed-tomography-based segmentation. Patients were stratified using muscle radiation attenuation of the whole muscle area (L3Muslce-RA), psoas RA (L3Psoas-RA) and intramuscular adipose tissue content (IMAC) values. L3Muslce-RA, L3Psoas-RA and IMAC performed well without major differences and identified patients at risk for inferior outcomes in the group analysis. Quartile-based analyses, receiver operating characteristic curve and correlation analyses showed a superior association of L3Muslce-RA with perioperative outcomes when compared to L3Psoas-RA and L3IMAC. Long-term outcome did not show any major differences between the used selection criteria. This study confirms the prognostic role of myosteatosis in OLT with a particularly strong value in the perioperative phase. Although, based on our data, L3Muscle-RA might be the most suitable and recommended selection criterion to assess CT-based myosteatosis when compared to L3Psoas-RA and L3IMAC, further studies are warranted to validate these findings.

Nerve Fibers in the Tumor Microenvironment as a Novel Biomarker for Oncological Outcome in Patients Undergoing Surgery for Perihilar Cholangiocarcinoma

INTRODUCTION

Perihilar cholangiocarcinoma (pCCA) is a biliary tract cancer with a dismal prognosis, with surgery being the only chance of cure. A characteristic aggressive biological feature of pCCA is perineural growth which is defined by the invasion of cancer cells to nerves and nerve fibers. Recently, nerve fiber density (NFD) was linked to oncological outcomes in various malignancies; however, its prognostic role in pCCA remains to be elucidated.

MATERIALS AND METHODS

Data of 101 pCCA patients who underwent curative-intent surgery between 2010 and 2019 were included in this study. Extensive group comparisons between patients with high and low NFD were carried out, and the association of cancer-specific survival (CSS) and recurrence-free survival with NFD and other clinicopathological characteristics was assessed using univariate and multivariable cox regression models.

RESULTS

Patients with high NFD showed a median CSS of 90 months (95% CI: 48-132, 3-year CSS = 77%, 5-year CSS = 72%) compared to 33 months (95% CI: 19-47, 3-year CSS = 46%, 5-year CSS = 32%) in patients with low NFD (p = 0.006 log rank). Further, N1 category (HR = 2.84, p = 0.001) and high NFD (HR = 0.41, p = 0.024) were identified as independent predictors of CSS in multivariable analysis. Patients with high NFD and negative lymph nodes showed a median CSS of 90 months (3-year CSS = 88%, 5-year CSS = 80%), while patients with either positive lymph nodes or low NFD displayed a median CSS of 51 months (3-year CSS = 59%, 5-year CSS = 45%) and patients with both positive lymph nodes and low NFD a median CSS of 24 months (3-year CSS = 26%, 5-year CSS = 16%, p = 0.001 log rank).

CONCLUSION

NFD has been identified as an important novel prognostic biomarker in pCCA patients. NFD alone and in combination with nodal status in particular allows to stratify pCCA patients based on their risk for inferior oncological outcomes after curative-intent surgery.

Prognostic role of the Donor Risk Index, the Eurotransplant Donor Risk Index, and the Balance of Risk score on graft loss after liver transplantation

This study aimed to identify cutoff values for donor risk index (DRI), Eurotransplant (ET)-DRI, and balance of risk (BAR) scores that predict the risk of liver graft loss. MEDLINE and Web of Science databases were searched systematically and unrestrictedly. Graft loss odds ratios and 95% confidence intervals were assessed by meta-analyses using Mantel-Haenszel tests with a random-effects model. Cutoff values for predicting graft loss at 3 months, 1 year, and 3 years were analyzed for each of the scores. Measures of calibration and discrimination used in studies validating the DRI and the ET-DRI were summarized. DRI ≥ 1.4 (six studies, n = 35 580 patients) and ET-DRI ≥ 1.4 (four studies, n = 11 666 patients) were associated with the highest risk of graft loss at all time points. BAR > 18 was associated with the highest risk of 3-month and 1-year graft loss (n = 6499 patients). A DRI cutoff of 1.8 and an ET-DRI cutoff of 1.7 were estimated using a summary receiver operator characteristic curve, but the sensitivity and specificity of these cutoff values were low. A DRI and ET-DRI score ≥ 1.4 and a BAR score > 18 have a negative influence on graft survival, but these cutoff values are not well suited for predicting graft loss.

Prognostic biomarkers for cholangiocarcinoma (CCA): state of the art

Introduction:Although advances in understanding the molecular basis of cholangiocarcinoma (CCA) have been made, surgery is the only curative therapy option and the overall prognosis of patients suffering from the disease remains poor. Therefore, estimation of prognosis based on known and novel biomarkers is essential for therapy guidance of CCA in both, curative and palliative settings.Areas covered:An extensive literature search on biomarkers for CCA with special emphasis on prognosis was performed. Based on this, prognostic biomarkers from serum, tumor tissue and other compartments that are currently in use or under evaluation for CCA were summarized in this review. Furthermore, an overview of new biomarkers was provided including those determined from extracellular vesicles (EVs), metabolites and nucleic acids. Finally, prognostic markers associated with potential new therapy options for the treatment of CCA were summed up.Expert opinion:So far, an optimal prognostic biomarker for CCA has not been described. However, based on the increasing knowledge about the molecular basis of CCA but also due to novel, innovative technologies, a plethora of novel prognostic biomarkers is currently under evaluation and will be available for CCA in future.

The role of recipient myosteatosis in graft and patient survival after deceased donor liver transplantation

BACKGROUND

Myosteatosis is associated with perioperative outcomes in orthotopic liver transplantation (OLT). Here, we investigated the effects of body composition and myosteatosis on long-term graft and patient survival following OLT.

METHODS

Clinical data from 225 consecutive OLT recipients from a prospective database were retrospectively analysed (May 2010 to December 2017). Computed tomography-based lumbar skeletal muscle index (SMI) (muscle mass) and mean skeletal muscle radiation attenuation (SM-RA) (myosteatosis) were calculated using a segmentation tool (3D Slicer). Patients with low skeletal muscle mass (low SMI) and myosteatosis (low SM-RA) were identified using predefined and validated cut-off values.

RESULTS

The mean donor and recipient age was 55 ± 16 and 54 ± 12 years, respectively. Some 67% of the recipients were male. The probability of graft and patient survival was significantly lower in patients with myosteatosis compared with patients with higher SM-RA values (P = 0.011 and P = 0.001, respectively). Low skeletal muscle mass alone was not associated with graft and patient survival (P = 0.273 and P = 0.278, respectively). Dividing the cohort into quartiles, based on the values of SMI and SM-RA, resulted in significant differences in patient but not in graft survival (P = 0.011). Even though multivariable analysis identified low SM-RA as an important prognostic marker (hazard ratio: 2.260, 95% confidence interval: 1.177-4.340, P = 0.014), myosteatosis lost its significance when early mortality (90 days) was excluded from the final multivariable model. Patients with myosteatosis showed significantly higher all-cause mortality and in particular higher rates of deaths due to respiratory and septic complication (P = 0.002, P = 0.022, and P = 0.049, respectively).

CONCLUSIONS

Preoperative myosteatosis may be an important prognostic marker in patients undergoing deceased donor liver transplantation. The prognostic value of myosteatosis seems to be particularly important in the early post-operative phase. Validation in prospective clinical trials is warranted.

Eosinophils attenuate hepatic ischemia-reperfusion injury in mice through ST2-dependent IL-13 production

Eosinophils are a myeloid cell subpopulation that mediates type 2 T helper cell immune responses. Unexpectedly, we identified a rapid accumulation of eosinophils in 22 human liver grafts after hepatic transplantation. In contrast, no eosinophils were detectable in healthy liver tissues before transplantation. Studies with two genetic mouse models of eosinophil deficiency and a mouse model of antibody-mediated eosinophil depletion revealed exacerbated liver injury after hepatic ischemia and reperfusion. Adoptive transfer of bone marrow-derived eosinophils normalized liver injury of eosinophil-deficient mice and reduced hepatic ischemia and reperfusion injury in wild-type mice. Mechanistic studies combining genetic and adoptive transfer approaches identified a critical role of suppression of tumorigenicity (ST2)-dependent production of interleukin-13 by eosinophils in the hepatoprotection against ischemia-reperfusion-induced injury. Together, these data provide insight into a mechanism of eosinophil-mediated liver protection that could serve as a therapeutic target to improve outcomes of patients undergoing liver transplantation.

Bacterial bile duct colonization in perihilar cholangiocarcinoma and its clinical significance

Abdominal infections including cholangitis represent a major problem in patients with perihilar cholangiocarcinoma (pCCA). Thus, we investigated bacterial colonization of the bile ducts and determined its impact on postoperative outcome focusing on abdominal infections. A cohort of 95 pCCA patients who underwent surgery between 2010 and 2019 with available intraoperative microbial bile cultures were analyzed regarding bile duct colonization and postoperative abdominal infection by group comparisons and logistic regressions. 84.2% (80/95) showed bacterial colonization of the bile ducts and 54.7% (52/95) developed postoperative abdominal infections. Enterococcus faecalis (38.8%, 31/80), Enterococcus faecium (32.5%, 26/80), Enterobacter cloacae (16.3%, 13/80) and Escherichia coli (11.3%, 9/80) were the most common bacteria colonizing the bile ducts and Enterococcus faecium (71.2%, 37/52), Enterococcus faecalis (30.8%, 16/52), Enterobacter cloacae (25.0%, 13/52) and Escherichia coli (19.2%, 10/52) the most common causes of postoperative abdominal infection. Further, reduced susceptibility to perioperative antibiotic prophylaxis (OR = 10.10, p = .007) was identified as independent predictor of postoperative abdominal infection. Bacterial colonization is common in pCCA patients and reduced susceptibility of the bacteria to the intraoperative antibiotic prophylaxis is an independent predictor of postoperative abdominal infections. Adapting antibiotic prophylaxis might therefore have the potential to improve surgical outcome pCCA patients.

Insufficient future liver remnant and preoperative cholangitis predict perioperative outcome in perihilar cholangiocarcinoma

BACKGROUND

Major liver resection has evolved as the mainstay of treatment for patients with perihilar cholangiocarcinoma (pCCA). Here we assessed the suitability of preoperative future liver remnant (FLR) measurement to predict perioperative complications, since surgical morbidity and mortality are high compared to other malignancies.

METHODS

Between 2011 and 2016, 91 patients with pCCA underwent surgery in curative intent at our institution. The associations of surgical complications with FLR and clinico-pathological characteristics were assessed using logistic regression analyses. Different methods of FLR assessment, the calculated-FLR (cFLR; ratio of FLR to total liver volume), standardized FLR (sFLR; ratio of FLR to liver volume estimated by body surface area) and FLR to bodyweight ratio (FLR/BW) were tested for validity.

RESULTS

Multivariable analysis identified preoperative cholangitis (Exp(B) = 0.236; p = 0.030) as the single significant predictor of postoperative mortality and cFLR (Exp(B) = 0.009, p = 0.004) as the single significant predictor of major postoperative morbidity (Clavien-Dindo ≥ 3b). Based on these findings we designed a futility criterion (cFLR<40% OR preoperative cholangitis) predicting in-house mortality.

CONCLUSIONS

In patients with pCCA, the preoperative FLR<40% as well as preoperative cholangitis are two risk factors to independently predict perioperative morbidity and mortality. The cFLR should be the preferred method of liver volumetry.

Impact of Angiogenesis- and Hypoxia-Associated Polymorphisms on Tumor Recurrence in Patients with Hepatocellular Carcinoma Undergoing Surgical Resection

Simple Summary

Hepatocellular carcinoma remains a leading cause of cancer-related death and the most common primary hepatic malignancy in the Western hemisphere. Previous research found that angiogenesis-related cytokines and elevated levels of interleukin 8 and vascular endothelial growth factor (VEGF) shorten the expected time of survival. Moreover, factors of tumor angiogenesis- and hypoxia-driven signaling pathways are already associated with worse outcome in disease-free survival in several tumor entities. Our study investigates the prognosis of hepatocellular carcinoma patients based on a selection of ten different single-nucleotide polymorphisms from angiogenesis, carcinogenesis, and hypoxia pathways. Our study with 127 patients found supporting evidence that polymorphisms in angiogenesis-associated pathways corelate with disease-free survival and clinical outcome in patients with hepatocellular carcinoma.

Abstract

Tumor angiogenesis plays a pivotal role in hepatocellular carcinoma (HCC) biology. Identifying molecular prognostic markers is critical to further improve treatment selection in these patients. The present study analyzed a subset of 10 germline polymorphisms involved in tumor angiogenesis pathways and their impact on prognosis in HCC patients undergoing partial hepatectomy in a curative intent. Formalin-fixed paraffin-embedded (FFPE) tissues were obtained from 127 HCC patients at a German primary care hospital. Genomic DNA was extracted, and genotyping was carried out using polymerase chain reaction (PCR)–restriction fragment length polymorphism-based protocols. Polymorphisms in interleukin-8 (IL-8) (rs4073; p = 0.047, log-rank test) and vascular endothelial growth factor (VEGF C + 936T) (rs3025039; p = 0.045, log-rank test) were significantly associated with disease-free survival (DFS). After adjusting for covariates in the multivariable model, IL-8 T-251A (rs4073) (adjusted p = 0.010) and a combination of “high-expression” variants of rs4073 and rs3025039 (adjusted p = 0.034) remained significantly associated with DFS. High-expression variants of IL-8 T-251A may serve as an independent molecular marker of prognosis in patients undergoing surgical resection for HCC. Assessment of the patients’ individual genetic risks may help to identify patient subgroups at high risk for recurrence following curative-intent surgery.

Prognostic evaluation of HCC patients undergoing surgical resection: an analysis of 8 different staging systems

Purpose

No consensus exists regarding the most appropriate staging system to predict overall survival (OS) for hepatocellular carcinoma (HCC) in surgical candidates. Thus, we aimed to determine the prognostic ability of eight different staging systems in a European cohort of patients undergoing liver resection for HCC.

Methods

Patients resected for HCC between 2010 and 2019 at our institution were analyzed with Kaplan-Meier and Cox regression analyses. Likelihood ratio (LR) χ² (homogeneity), linear trend (LT) χ² (discriminatory ability), and Akaike Information Criterion (AIC, explanatory ability) were used to determine the staging system with the best overall prognostic performance.

Results

Liver resection for HCC was performed in 160 patients. Median OS was 39 months (95% confidence interval (CI): 32–46 months) and median RFS was 26 months (95% CI: 16–34 months). All staging systems (BCLC, HKLC, Okuda, CLIP, ITA.LI.CA staging and score, MESH, and GRETCH) showed significant discriminatory ability regarding OS, with ITA.LI.CA score (LR χ² 30.08, LT χ² 13.90, AIC 455.27) and CLIP (LR χ² 28.65, LT χ² 18.95, AIC 460.07) being the best performing staging systems.

Conclusions

ITA.LI.CA and CLIP are the most suitable staging system to predict OS in European HCC patients scheduled for curative-intent surgery.

Decrease of renal resistance during hypothermic oxygenated machine perfusion is associated with early allograft function in extended criteria donation kidney transplantation

Hypothermic oxygenated machine perfusion (HOPE) was recently tested in preclinical trials in kidney transplantation (KT). Here we investigate the effects of HOPE on extended-criteria-donation (ECD) kidney allografts (KA). Fifteen ECD-KA were submitted to 152 ± 92 min of end-ischemic HOPE and were compared to a matched group undergoing conventional-cold-storage (CCS) KT (n = 30). Primary (delayed graft function-DGF) and secondary (e.g. postoperative complications, perfusion parameters) endpoints were analyzed within 6-months follow-up. There was no difference in the development of DGF between the HOPE and CCS groups (53% vs. 33%, respectively; p = 0.197). Serum urea was lower following HOPE compared to CCS (p = 0.003), whereas the CCS group displayed lower serum creatinine and higher eGFR rates on postoperative days (POD) 7 and 14. The relative decrease of renal vascular resistance (RR) following HOPE showed a significant inverse association with serum creatinine on POD1 (r = − 0.682; p = 0.006) as well as with serum urea and eGFR. Besides, the relative RR decrease was more prominent in KA with primary function when compared to KA with DGF (p = 0.013). Here we provide clinical evidence on HOPE in ECD-KT after brain death donation. Relative RR may be a useful predictive marker for KA function. Further validation in randomized controlled trials is warranted.

Trial registration: clinicaltrials.gov (NCT03378817, Date of first registration: 20/12/2017).

Adenosine A2a Receptor Stimulation Attenuates Ischemia-Reperfusion Injury and Improves Survival in A Porcine Model of DCD Liver Transplantation

Orthotopic liver transplantation (OLT) using allografts from donation after circulatory death (DCD) is potentially associated with compromised clinical outcomes due to ischemia-reperfusion injury (IRI)-induced organ damage and graft-related complications. The aim of this study was to provide in vivo data on the effects of adenosine A2a receptor stimulation in a clinically relevant large animal model of DCD liver transplantation. Cardiac arrest was induced in German Landrace pigs (n = 10; 20-25 kg). After 30 min of warm ischemia, the donor liver was retrieved following a cold flush with 3 L of histidine-tryptophan-ketoglutarate-HTK solution. Animals of the treatment group (n = 5/group) received a standard dose of the selective adenosine receptor agonist CGS 21680 added to the cold flush. All grafts were stored for 4.5 h at 4 °C in HTK-solution before OLT. Hepatocellular injury, apoptosis, protein kinase A-PKA activity, graft microcirculation, liver function, and animal survival were assessed. Compared to untreated livers, adenosine A2a receptor stimulation resulted in improved tissue microcirculation (103% ± 5% vs. 38% ± 4% compared to baseline; p < 0.05), accelerated functional recovery of the graft (indocyanine green-plasma disappearance rate (ICG-PDR) of 75% ± 18% vs. 40% ± 30% after 3 h), increased PKA activity ratio (56% ± 3% vs. 32% ± 3%; p < 0.001 after 1 h), and consequently reduced tissue necrosis and apoptosis. The potent protective effects were clinically manifested in significantly improved survival in the treatment group after 72 h (100% vs. 40%; p = 0.04). The ex vivo administration of adenosine A2a receptor agonist during the back-table flush mitigates IRI-mediated tissue damage and improves functional graft recovery and survival in a large animal model of DCD liver transplantation.

Low Postoperative Platelet Counts Are Associated with Major Morbidity and Inferior Survival in Adult Recipients of Orthotopic Liver Transplantation

BACKGROUND

Platelets (PLT) play an essential functional role in cellular injury and liver regeneration following partial hepatectomy and orthotopic liver transplantation (OLT). Here, we investigated the association of postoperative PLT counts with short- and long-term outcomes in adult OLT recipients.

METHODS

Three hundred consecutive patients from our prospective OLT database were analyzed retrospectively (May 2010-November 2017). Ninety-day post-OLT complications were graded using the Clavien-Dindo (CD) classification and quantified by the comprehensive complication index (CCI). To determine the prognostic accuracy of PLT counts, the area under the receiver operating characteristic curve (AUROC) was calculated for major complications (CD ≥ 3b). Parametric and non-parametric tests were applied for subgroup analyses. Uni- and multivariable logistic regression analyses were performed to identify risk factors for major complications. Graft and patient survival were analyzed using the Kaplan-Meier method as well as uni- and multivariable Cox regression analyses.

RESULTS

Postoperative day 6 PLT counts < 70 × 10⁹/L (POD6-70) were identified as the best cutoff for predicting major complications (AUROC = 0.7; p < 0.001; Youden index 0.317). The stratification of patients into low- (n = 113) and high-PLT (n = 187) groups highlighted significant differences in major complications (CCI 68 ± 29 vs. 43 ± 28, p < 0.001); length of hospital and intensive care unit (ICU) stay (53 ± 43 vs. 31 ± 25, p < 0.001; 21 ± 29 vs. 7 ± 11, p < 0.001, respectively) and estimated procedural costs. POD6-70 was associated with inferior 5-year graft survival. Multivariable logistic regression analysis identified POD6-70 as an independent predictor of major complications (odds ratio 2.298, confidence intervals 1.179-4.478, p = 0.015).

CONCLUSION

In OLT patients, a PLT count on POD6 of less than 70 × 10⁹/L bears a prognostic significance warranting further investigations.

Orthotopic Kidney Auto-Transplantation in a Porcine Model Using 24 Hours Organ Preservation And Continuous Telemetry

In the present era of organ transplantation with critical organ shortage, various strategies are employed to expand the pool of available allografts for kidney transplantation (KT). Even though, the use of allografts from extended criteria donors (ECD) could partially ease the shortage of organ donors, ECD organs carry a potentially higher risk for inferior outcomes and postoperative complications. Dynamic organ preservation techniques, modulation of ischemia-reperfusion and preservation injury, and allograft therapies are in the spotlight of scientific interest in an effort to improve allograft utilization and patient outcomes in KT. Preclinical animal experiments are playing an essential role in translational research, especially in the medical device and drug development. The major advantage of the porcine orthotopic auto-transplantation model over ex vivo or small animal studies lies within the surgical-anatomical and physiological similarities to the clinical setting. This allows the investigation of new therapeutic methods and techniques and ensures a facilitated clinical translation of the findings. This protocol provides a comprehensive and problem-oriented description of the porcine orthotopic kidney auto-transplantation model, using a preservation time of 24 hours and telemetry monitoring. The combination of sophisticated surgical techniques with highly standardized and state-of-the-art methods of anesthesia, animal housing, perioperative follow up, and monitoring ensure the reproducibility and success of this model.

ALPPS versus two-stage hepatectomy for colorectal liver metastases--a comparative retrospective cohort study

Abstract

Background

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) and two stage hepatectomy with inter-stage portal vein embolization (TSH/PVE) are surgical maneuvers applied in patients with advanced malignancies considered unresectable by means of conventional liver surgery. The aim of this report is to compare the oncologic outcome and technical feasibility of ALPPS and TSH/PVE in the scenario of colorectal liver metastases (CRLM).

Methods

All consecutive patients who underwent either ALPPS or TSH/PVE for CRLM between 2011 and 2017 in one hepatobiliary center were analyzed and compared regarding perioperative and long-term oncologic outcome.

Results

A cohort of 58 patients who underwent ALPPS (n = 21) or TSH/PVE (n = 37) was analyzed. The median overall survival (OS) was 28 months and 34 months after ALPPS and TSH/PVE (p = 0.963), respectively. The median recurrence-free survival (RFS) was higher following ALPPS with 19 months than following TSH/PVE with 10 months, but marginally failed to achieve statistical significance (p = 0.05). There were no differences in morbidity and mortality after stages 1 and 2. Patients undergoing ALPPS due to insufficient hypertrophy after TSH/PVE (rescue-ALPPS) displayed similar oncologic outcome as patients treated by conventional ALPPS or TSH/PVE (p = 0.971).

Conclusions

ALPPS and TSH/PVE show excellent technical feasibility and comparable long-term oncologic outcome in CRLM. Rescue ALPPS appears to be a viable option for patients displaying insufficient hypertrophy after a TSH/PVE approach.

Ischemia-Reperfusion Injury in Marginal Liver Grafts and the Role of Hypothermic Machine Perfusion: Molecular Mechanisms and Clinical Implications

Ischemia-reperfusion injury (IRI) constitutes a significant source of morbidity and mortality after orthotopic liver transplantation (OLT). The allograft is metabolically impaired during warm and cold ischemia and is further damaged by a paradox reperfusion injury after revascularization and reoxygenation. Short-term and long-term complications including post-reperfusion syndrome, delayed graft function, and immune activation have been associated with IRI. Due to the current critical organ shortage, extended criteria grafts are increasingly considered for transplantation, however, with an elevated risk to develop significant features of IRI. In recent years, ex vivo machine perfusion (MP) of the donor liver has witnessed significant advancements. Here, we describe the concept of hypothermic (oxygenated) machine perfusion (HMP/HOPE) approaches and highlight which allografts may benefit from this technology. This review also summarizes clinical applications and the main aspects of ongoing randomized controlled trials on hypothermic perfusion. The mechanistic aspects of IRI and hypothermic MP-which include tissue energy replenishment, optimization of mitochondrial function, and the reduction of oxidative and inflammatory damage following reperfusion-will be comprehensively discussed within the context of current preclinical and clinical evidence. Finally, we highlight novel trends and future perspectives in the field of hypothermic MP in the context of recent findings of basic and translational research.

Left- versus right-sided hepatectomy with hilar en-bloc resection in perihilar cholangiocarcinoma

BACKGROUND

Major liver resections with portal vein resection (PVR) have emerged as the preferred treatment for patients with perihilar cholangiocarcinoma (pCCA). Whether the resection of the liver should be preferably performed as left- (LH) or right-sided hepatectomy (RH) with or without hilar en-bloc technique is still subject of ongoing debate.

METHODS

Between 2011 and 2016, 91 patients with pCCA underwent surgery in curative intent at our institution. Perioperative, pathological and survival data from all consecutive patients undergoing hilar en-bloc resection for pCCA were analyzed retrospectively. Patients undergoing hepatoduodenectomy (n = 8) or ALPPS (Associating liver partition and portal vein ligation for staged hepatectomy) (n = 2) were excluded from the analysis.

RESULTS

Tumor grading, microvascular invasion, lymphovascular invasion, N-category, T-category, R-status and UICC-tumor staging were similar in the RH (n = 45) and LH (n = 36) groups. Perioperative morbidity and mortality were higher after RH compared to LH (mortality: 15.6% (7/45) vs. 8.3% (3/36) p = 0.003). Three-year (62% vs. 51%) and the 5-year OS (30% vs. 46%) were comparable between LH and RH groups respectively (p = 0.519, log rank).

CONCLUSIONS

The present study supports the concept of surgically aggressive therapy in pCCA. LH and RH hilar en-bloc resection demonstrate a comparable long-term survival, suggesting that LH hilar en-bloc resections are feasible and safe in high-volume centers.

Myosteatosis to predict inferior perioperative outcome in patients undergoing orthotopic liver transplantation

Muscle wasting and alterations of body composition are linked to clinical outcomes in numerous medical conditions. The role of myosteatosis in posttransplant outcomes remains to be determined. Here we investigated skeletal muscle mass and myosteatosis as prognostic factors in patients undergoing orthotopic liver transplantation (OLT). The data of 225 consecutive OLT recipients from a prospective database were retrospectively analyzed (May 2010-December 2017). Computed tomography-based skeletal-muscle-index (muscle mass), visceral-fat-area (visceral adiposity), and mean skeletal-muscle-radiation-attenuation (myosteatosis) were calculated using a segmentation tool. Cut-off values of myosteatosis resulted in a good stratification of patients into low- and high-risk groups in terms of morbidity (Clavien-Dindo ≥3b). Patients with myosteatosis had significantly higher complication rates (90-day Comprehensive Complication Index 68 ± 32 vs 44 ± 30, P < .001) and also displayed significantly longer intensive care (18 ± 25 vs 11 ± 21 days, P < .001) and hospital stay (56 ± 55 vs 33 ± 24 days, P < .001). Estimated costs were 44% higher compared to patients without myosteatosis. Multivariable analysis identified myosteatosis as an independent prognostic factor for major morbidity (odds ratio: 2.772, confidence interval: 1.516-5.066, P = .001). Adding myosteatosis to the well-established Balance-of-Risk-(BAR) score resulted in an increased prognostic value compared to the original BAR score. Myosteatosis may be a useful parameter to predict perioperative outcome in patients undergoing OLT, supporting the role of muscle quality (myosteatosis) over quantity (muscle mass) in this setting.

Influence of peritoneal carcinomatosis on perioperative outcome in palliative gastric bypass for malignant gastric outlet obstruction - a retrospective cohort study

Background

Malignant gastric outlet obstruction (GOO) is commonly associated with the presence of peritoneal carcinomatosis (PC) and preferably treated by surgical gastrojejunostomy (GJJ) in patients with good performance. Here, we aim to investigate the role of PC as a risk factor for perioperative morbidity and mortality in patients with GOO undergoing GJJ.

Methods

Perioperative data of 72 patients with malignant GOO who underwent palliative GJJ at our institution between 2010 and 2019 were collected within an institutional database.

To compare perioperative outcomes of patients with and without PC, extensive group analyses were carried out.

Results

A set of 39 (54.2%) patients was histologically diagnosed with concomitant PC while the remaining 33 (45.8%) patients showed no clinical signs of PC. In-house mortality due to surgical complications was significantly higher in patients with PC (9/39, 23.1%) than in patients without PC (2/33, 6.1%, p = .046). Considerable differences were observed in terms of surgical complications such as anastomotic leakage rates (2.8% vs. 0%, p = .187), delayed gastric emptying (33.3% vs. 15.2%, p = .076), paralytic ileus (23.1% vs. 9.1%, p = .113), and pneumonia (17.9% vs. 12.1%, p = .493) without reaching the level of statistical significance.

Conclusions

PC is an important predictor of perioperative morbidity and mortality patients undergoing GJJ for malignant GOO.