Dynamics of Peripheral Blood Immune Cells during the Perioperative Period after Digestive System Resections: A Systematic Analysis of the Literature.

An operation in itself is a kind of trauma and may lead to immunosuppression followed by a bounce back. Not many studies exist that describe dynamics of the distribution of peripheral blood (PB) immune cells during the perioperative period. Considering this scarcity, we aggregated the data on the dynamics of immune cells in patients with digestive system resections during the perioperative period and the relationship with short- and long-term prognoses. By the systematic retrieval of documents, we collected perioperative period data on white blood cells (WBC), lymphocytes, neutrophil-lymphocyte ratio (NLR), CD4+ T cells, CD8+ T cells, helper T cells (Th), B cells, natural killer cells (NK), dendritic cells (DCs), regulatory T cells (Tregs), regulatory B cells (Bregs), and Myeloid derived suppressor cells (MDSC). The frequency and distribution of these immune cells and the relationship with the patient's prognosis were summarized. A total of 1916 patients' data were included. Compared with before surgery, WBC, lymphocytes, CD4+ cells, CD8+ T cells, MDSC, and NK cells decreased after surgery, and then returned to preoperative levels. After operation DCs increased, then gradually recovered to the preoperative level. No significant changes were found in B cell levels during the perioperative period. Compared with the preoperative time-point, Tregs and Bregs both increased postoperatively. Only high levels of the preoperative and/or postoperative NLR were found to be related to the patient's prognosis. In summary, the surgery itself can cause changes in peripheral blood immune cells, which might change the immunogenicity. Therefore, the immunosuppression caused by the surgical trauma should be minimized. In oncological patients this might even influence long-term results.

Hypothermic Oxygenated Machine Perfusion (HOPE) Prior to Liver Transplantation Mitigates Post-Reperfusion Syndrome and Perioperative Electrolyte Shifts.

(1) Background: Post-reperfusion syndrome (PRS) and electrolyte shifts (ES) represent considerable challenges during liver transplantation (LT) being associated with significant morbidity. We aimed to investigate the impact of hypothermic oxygenated machine perfusion (HOPE) on PRS and ES in LT. (2) Methods: In this retrospective study, we compared intraoperative parameters of 100 LTs, with 50 HOPE preconditioned liver grafts and 50 grafts stored in static cold storage (SCS). During reperfusion phase, prospectively registered serum parameters and vasopressor administration were analyzed. (3) Results: Twelve percent of patients developed PRS in the HOPE cohort vs. 42% in the SCS group (p = 0.0013). Total vasopressor demand in the first hour after reperfusion was lower after HOPE pretreatment, with reduced usage of norepinephrine (−26%; p = 0.122) and significant reduction of epinephrine consumption (−52%; p = 0.018). Serum potassium concentration dropped by a mean of 14.1% in transplantations after HOPE, compared to a slight decrease of 1% (p < 0.001) after SCS. The overall incidence of early allograft dysfunction (EAD) was reduced by 44% in the HOPE group (p = 0.04). (4) Conclusions: Pre-transplant graft preconditioning with HOPE results in higher hemodynamic stability during reperfusion and lower incidence of PRS and EAD. HOPE has the potential to mitigate ES by preventing hyperpotassemic complications that need to be addressed in LT with HOPE-pre-treated grafts.

Textbook outcome in hepato-pancreato-biliary surgery: systematic review.

BACKGROUND: Textbook outcome (TO) is a multidimensional measure reflecting the ideal outcome after surgery. As a benchmarking tool, it provides an objective overview of quality of care. Uniform definitions of TO in hepato-pancreato-biliary (HPB) surgery are missing. This study aimed to provide a definition of TO in HPB surgery and identify obstacles and predictors for achieving it. METHODS: A systematic literature search was conducted using PubMed, Embase, and Cochrane Database according to PRISMA guidelines. Studies published between 1993 and 2021 were retrieved. After selection, two independent reviewers extracted descriptive statistics and derived summary estimates of the occurrence of TO criteria and obstacles for achieving TO using co-occurrence maps. RESULTS: Overall, 30 studies were included. TO rates ranged between 16-69 per cent. Commonly chosen co-occurring criteria to define TO included 'no prolonged length of stay (LOS)', 'no complications', 'no readmission', and 'no deaths'. Major obstacles for achieving TO in HPB surgery were prolonged LOS, complications, and readmission. On multivariable analysis, TO predicted better overall and disease-free survival in patients with cancer. Achievement of TO was more likely in dedicated centres and associated with procedural and structural indicators, including high case-mix index and surgical volume. CONCLUSION: TO is a useful quality measure to benchmark surgical outcome. Future definitions of TO in HPB surgery should include 'no prolonged LOS', 'no complications', 'no readmission', and 'no deaths'.

Liver Transplant Oncology: Towards Dynamic Tumor-Biology-Oriented Patient Selection.

While liver transplantation was initially considered as a curative treatment modality only for hepatocellular carcinoma, the indication has been increasingly extended to other tumor entities over recent years, most recently to the treatment of non-resectable colorectal liver metastases. Although oncologic outcomes after liver transplantation (LT) are consistently good, organ shortage forces stringent selection of suitable candidates. Dynamic criteria based on tumor biology fulfill the prerequisite of an individual oncological prediction better than traditional morphometric criteria based on tumor burden. The availability of specific (neo-)adjuvant therapies and customized modern immunosuppression may further contribute to favorable post-transplantation outcomes on the one hand and simultaneously open the path to LT as a curative option for advanced stages of tumor patients. Herein, we provide an overview of the oncological LT indications, the selection process, and expected oncological outcome after LT.

Highly differential count of circulating and tumor infiltrating immune cells in patients with non-HCV/non-HBV hepatocellular carcinoma.

BACKGROUND: Liver transplantation and liver resection are curative options for early hepatocellular carcinoma (HCC). The outcome is in part depended on the immunological response to the malignancy. In this study, we aimed to identify immunological profiles of non-HCV/non-HBV HCC patients. METHODS: Thirty-nine immune cell subsets were measured with multicolor flow cytometry. This immunophenotyping was performed in peripheral blood (PB) and tumor specimens of 10 HCC resection patients and 10 healthy donors. The signatures of the highly differential leukocyte count (hDIF) were analyzed using multidimensional techniques. Functional capability was measured using intracellular IFN-γ staining (Trial Registration DRKS00013567). RESULTS: The hDIF showed activation (subsets of T-, B-, NK- and dendritic cells) and suppression (subsets of myeloid-derived suppressor cells and T- and B-regulatory cells) of the antitumor response. Principal component analysis of PB and tumor infiltrating leukocytes (TIL) illustrated an antitumor activating gradient. TILs showed functional capability by secreting IFN-γ but did not kill HCC cells. CONCLUSIONS: In conclusion, the measurement of the hDIF shows distinct differences in immune reactions against non-HBV/non-HCV HCC and illustrates an immunosuppressive gradient toward peripheral blood. TRIAL REGISTRATION: DRKS00013567.

The interactions between major immune effector cells and Hepatocellular Carcinoma: A systematic review.

BACKGROUND: Hepatocellular carcinoma (HCC) is the most common liver neoplasm with high morbidity and mortality. Tumor immunotherapy might be promising adjuvant therapy for HCC after surgery. To better develop HCC immunotherapy, comprehensive understanding of cell-cell interactions between immune effector cells and HCC cells remains crucial. AIM: To review the existing studies to summarize the cell-cell interactions between major immune effector cells and HCC cells providing new data for HCC immunotherapy. METHODS: A systematic review was conducted by searching PubMed database covering all papers published in recent five years up to January 2020. The guidelines of the preferred reporting items for systematic reviews were firmly followed. RESULTS: There are 9 studies researching the interactions between CD8+ T lymphocytes and HCC cells and 22 studies researching that between natural killer (NK) cells and HCC cells. Among the 9 studies, 6 studies reported that CD8+ T lymphocytes showed cytotoxicity towards HCC cells while 3 studies found CD8+ T lymphocytes were impaired by HCC cells. Among the 22 studies, 20 studies presented that NK cells could inhibit HCC cells. Two studies were found to report NK cell dysfunction in HCC. CONCLUSION: Based on the systematic analysis, we concluded that CD8+ T lymphocytes and NK cells can inhibit HCC cells. While in turn, HCC cells can also result in the dysfunction of those effector cells through various mechanisms. Organoids and direct contact cell co-culture with primary HCC cells and TILs should be the most innovative way to investigate the interactions and develop novel immunotherapy.

The Psychosocial Burden on Liver Transplant Recipients during the COVID-19 Pandemic.

INTRODUCTION: Due to the coronavirus disease 19 (COVID-19) pandemic, multiple measures have been implemented including social distancing and curfews. Both the disease and measures might cause stress, particularly in persons at risk, such as liver transplant (LT) recipients. Here, we evaluated the impact on psychosocial well-being of LT recipients. METHODS: Seventy-nine LT recipients and 83 nontransplanted controls participated in this study. Questionnaires comprising the WHO-five well-being index (WHO-5), the University of California at Los Angeles (UCLA) Loneliness Scale, and the preliminary COVID-19 Pandemic Mental Health Questionnaire (CoPaQ) were distributed among them. For the WHO-5 and UCLA Loneliness Scale, means of sum scores were compared between both groups, while a comparison on item level was conducted for the CoPaQ. RESULTS: The general well-being was similar in LT recipients and controls (WHO-5: 64.0 ± 20.5% vs. 66.4 ± 17.3%), while the UCLA Loneliness Scale indicated a higher level of perceived social isolation (1.90 ± 0.51 vs. 1.65 ± 0.53, p = 0.001). The CoPaQ indicated higher risk perception regarding health issues, in particular concerning the fear of having severe consequences in case of a COVID-19 infection (3.1 ± 1.1 vs. 2.2 ± 1.3, p < 0.001), higher risk-avoiding behavior and stronger adherence to pandemic measures in LT recipients. CONCLUSION: During the COVID-19 pandemic, LT recipients displayed a higher risk perception, a more pronounced risk-avoiding behavior and a higher perception of loneliness, while the overall well-being was comparable to nontransplanted controls.

The predictive value of tumor infiltrating leukocytes in Hepatocellular Carcinoma: A systematic review and meta-analysis.

BACKGROUND: For Hepatocellular carcinoma (HCC) surgery either through resection or transplantation often provides the only chance for cure. Since hepatocarcinogenesis and postsurgical prognosis is not only dependent on cirrhosis but also on immune activation and exhaustion, many studies have investigated tumor infiltrating leukocyte (TIL) subsets. This systematic review and meta-analysis aims at describing the cell groups and their predictive power regarding overall (OS), disease free (DFS) and recurrence free survival (RFS). MATERIAL AND METHODS: A systematic search of the PubMed database was conducted (PROSPERO 172324). Data on CD3+, CD8+, Treg, B cells, macrophages, neutrophil and NK-cells were collected from Pubmed and related references up to December 2018. Overall (OS), disease-free (DFS) and recurrence free survival (RFS) in dependence of high vs. low infiltration rates were compared using a random effects meta-analysis. RESULTS: Altogether data from 3541 patients enrolled in 20 publications were included. Except for Tregs and Neutrophils, heterogeneity analysis was found to be moderate to high across the studies. High CD3+, CD8+, NK-cell infiltration predicted better survival (OS, DFS and RFS; p < 0.05). Higher Treg and Neutrophil infiltration predicted lower OS and DFS. For Macrophages and B cells no difference in survival could be found. DISCUSSION: As with other solid tumors immune infiltration has a great influence on survival after resection. However, a considerable publication bias cannot be ruled out in mostly retrospective analyses. Nevertheless, in light of novel immune modulatory treatments this opens a new avenue towards effective and well-tolerated adjuvant treatment.

Liver transplantation versus watchful waiting in hepatocellular carcinoma patients with complete response to bridging therapy - a retrospective observational study.

Bridging therapy to prevent progression on the waiting list can result in a sustained complete response (sCR). In some patients, the liver transplantation (LT) risk might exceed those of tumor recurrence. We thus evaluated whether a watchful waiting (CR-WW) strategy could be a feasible alternative to transplantation (CR-LT). We performed a retrospective analysis of overall survival (OS) and recurrence-free survival (RFS) of patients with a sCR (CR > 6 months). Permitted bridging included thermoablation, resection, and combinations of either with transarterial chemoembolization. Patients were divided into the intended treatment strategies CR-WW and CR-LT. 39 (18.40%) sCR patients from 212 were investigated. 22 patients were treated with a CR-LT and 17 patients a CR-WW strategy. Five-year RFS was lower in the CR-WW than in the CR-LT group [53.3% (22.1%; 77.0%) and 84.0% (57.6%; 94.7%)]. 29.4% (5/17) CR-WW patients received salvage transplantation because of recurrence. OS (5-year) was 83.9% [56.8%; 94.7%] after LT and 75.4% [39.8%; 91.7%] after WW. Our analysis shows that the intuitive decision made by our patients in agreement with their treating physicians for a watchful waiting strategy in sCR can be justified. Applied on a larger scale, this strategy could help to reduce the pressure on the donor pool.

A novel machine learning algorithm to predict disease free survival after resection of hepatocellular carcinoma.

BACKGROUND: Due to organ shortage, liver transplantation (LT) in hepatocellular carcinoma (HCC) patients can only be offered subsidiary to other curative treatments, including liver resection (LR). We aimed at developing and validating a machine-learning algorithm (ML) to predict which patients are sufficiently treated by LR. METHODS: Twenty-six preoperatively available routine laboratory values along with standard clinical-pathological parameters [including the modified Glascow Prognostic Score (mGPS), the Kings Score (KS) and the Model of Endstage Liver Disease (MELD)] were retrieved from 181 patients who underwent partial LR due to HCC in non-cirrhosis or compensated cirrhosis from January 2007 through March 2018 at our institution. These data were processed using a Random Forest (RF)-based workflow, which included preprocessing, recursive feature elimination (RFE), resampling, training and cross-validation of the RF model. A subset of untouched patient data was used as a test cohort. Basing on the RF prediction, test data could be stratified according to high (HR) or low risk (LR) profile characteristics. RESULTS: RFE analysis provided 6 relevant outcome predictors: mGPS, aPTT, CRP, largest tumor size, number of lesions and age at time of operation. After down-sampling, the predictive value of our model was 0.788 (0.658-0.919) for early DFS. 16.7% of HR and 74.2% of LR patients survived 2 years of follow-up (P<0.001). CONCLUSIONS: Our RF model, based solely on clinical parameters, proved to be a powerful predictor of DFS. These results warrant a prospective study to improve the model for selection of suitable candidates for LR as alternative to transplantation. The predictive model is available online: tiny.cc/hcc_model.

Liver Transplantation for Extended Criteria Hepatocellular Carcinoma Using Stable Response to Locoregional Therapy and Alpha-Fetoprotein as Selection Criteria.

INTRODUCTION: Current practice to only prioritize hepatocellular carcinoma (HCC) that fulfill the Milan criteria (INMC) is changing, since it causes the exclusion of patients who could benefit from liver transplantation. To select patients outside MC (OUTMC) for transplantation, we implemented extended selection criteria without up-front morphometric restrictions containing surrogate parameters of tumor biology. METHODS: OUTMC patients were considered without restrictions of morphometrics and received locoregional treatment after interdisciplinary consultation. Our dynamic selection criteria for OUTMC patients required (INMUC): (1) treatment response over (2) at least 6 months and (3) alpha-fetoprotein ≤400 ng/mL over the entire evaluation period. Patients with INMC tumors served as control and internal validation cohort. RESULTS: 31 of 170 liver transplant candidates were OUTMC. Of these, 8 dropped out. The remaining 23 patients met the selection criteria and underwent transplantation. Recurrence-free survival was higher in patients transplanted INMC compared to those OUTMC INMUC (92.2% vs. 70.8%; p = 0.026) after 5 years of follow-up. Overall survival showed no significant difference (p = 0.552). With dynamic selection of transplant candidates, recurrence could also be predicted for the INMC patients as internal validation cohort (c-index: 0.896; CI 0.588-0.981, p = 0.005). CONCLUSION: Dynamic selection criteria for the stratification of patients with OUTMC HCCs is feasible and allows for excellent long-term results and acceptable tumor recurrence rates comparable to INMC patients.

Liver transplantation in patients with a history of migration-A German single center comparative analysis.

Liver transplant (LT) programs in Germany increasingly face a multiethnic patient population. To date no outcome data for LT in patients with a history of migration is available for Germany. This complicates decision-making before wait-listing such patients. We conducted a single-center cohort analysis of all primary LT between April 2007 and December 2015, stratified for the history of migration to investigate differences in the outcome. We found transplant rates resembling the proportion of persons with a history of migration in the general public in the region of our center. Differences were found concerning age at LT and prevalence of underlying diseases. Re-Transplant rates, Kaplan-Meier Estimates for overall survival, also after stratification for viral hepatitis, sex, ethnicity or presence of a language-barrier showed no statistical differences. The multivariate analysis showed no migration-related covariate associated with a negative outcome. These results stand in contrast to most of the previous evidence from North America and the UK and need to be taken into consideration during the wait-listing process of patients with a history of migration in need of a LT in centers in the Eurotransplant region.

Development of novel biological resection criteria for safe and oncologically satisfying resection of hepatocellular carcinoma.

OBJECTIVE: To develop criteria for safe and oncologically satisfying liver resection in case of early hepatocellular carcinoma with a 5-year overall survival (OS) similar to liver transplantation. SUMMARY BACKGROUND DATA: Liver resection (LR) and liver transplantation (LT) are potentially curative treatment options for hepatocellular carcinoma. Generally, LT achieves better OS. Due to organ shortage, however not all patients can receive a LT. METHODS: To decide which patients to resect and which to transplant we have developed biological resection criteria (BRC) as a compound out of mGPS (modified Glascow Prognostic Scale) and the Kings-Score (for HCV cirrhosis). These are based on routine clinical values that reflect both liver function and tumor biology/immunology. RESULTS: 276 patients were analyzed. Patients undergoing LR within BRC (inBRC) had a significantly better overall (73.6% vs. 35.4%, (p < 0.001)) and disease-free survival (54.7% vs. 17.2%, (p < 0.001)) as compared to patients outside the BRC (outBRC). The predictive value of BRC was independent of tumor burden. In a subgroup analysis outBRC patients had significantly worse outcome after major resection. In LT patients BRC had no predictive value. CONCLUSIONS: BRC may be a valuable tool to predict survival after LR for HCC. Patients resected inBRC may achieve comparable survival as LT. LR in outBRC patients are unlikely to be curative. All outBRC patients should be monitored closely for salvage LT.

Perivascular Tumor-Infiltrating Leukocyte Scoring for Prognosis of Resected Hepatocellular Carcinoma Patients.

Liver resection is a curative treatment for hepatocellular carcinoma (HCC). Tumor-infiltrating leukocytes (TILs) are important players in predicting HCC recurrence. However, the invasive margin could not be confirmed as relevant for HCC. The migration of immune cells into HCC may originate from intratumoral vessels. No previous study has examined perivascular (PV) infiltration. Tumors from 60 patients were examined. Immunohistochemistry was performed against CD3, CD8, CD20, and CD66b. TILs were counted in the PV regions using an algorithm for quantification of the tumor immune stroma (QTiS). The results were correlated with overall (OS) and disease-free survival (DFS), clinical parameters, and laboratory values. PV infiltration of TILs was predominant in resected HCC. Higher PV infiltration of CD3⁺ (p = 0.016) and CD8⁺ (p = 0.028) independently predicted better OS and DFS, respectively. CD20⁺ showed a trend towards better DFS (p = 0.076). Scoring of CD3⁺, CD8⁺, and CD20⁺ independently predicted OS and DFS (p < 0.01). The amount of perivascular-infiltrating CD3⁺ cells is an independent predictor of better OS, and CD8⁺ cells independently predict prolonged DFS. Our novel perivascular infiltration scoring (PVIS) can independently predict both DFS and OS in resected HCC patients.

Development of a reliable and accurate algorithm to quantify the tumor immune stroma (QTiS) across tumor types.

The tumor microenvironment plays an important role in the tumor biology. Overall survival of tumor patients after resection is influenced by tumor-infiltrating lymphocytes (TILs) as a component of the tumor stroma. However, it is not clear how to assess TILs in the tumor stroma due to heterogeneous methods in different cancer types. Therefore, we present a novel Quantification of the Tumor immune Stroma (QTiS) Algorithm to reliably and accurately quantify cells in the tumor stroma. Immunohistochemical staining of CD3 and CD8 cells in sections of metastatic colorectal cancer (mCRC), ovarian cancer (OvCa), hepatocellular carcinoma (HCC), and pancreatic ductal adenocarcinoma (PDAC), alltogether N = 80, was performed. Hot spots of infiltrating immune cells are reported in the literature. Reliability of the hot spot identification of TILs was examined by two blinded observers. Accuracy was tested in 1 and 3 hot spots using computed counting methods (ZEN 2 software counting (ZC), ImageJ software with subjective threshold (ISC) and ImageJ with color deconvolution (IAC)) and compared to manual counting. All tumor types investigated showed an accumulation of TILs in the tumor stroma (peri- and intratumoral). Reliability between observers indicated a high level consistency. Accuracy for CD8+/CD3+ ratio and absolute cell count required 1 and 3 hot spots, respectively. ISC was found to be the best for paraffin sections, whereas IAC was ideal for frozen sections. ImageJ software is cost-effective and yielded the best results. In conclusion, an algorithm for quantification of tumoral stroma could be established. With this QTiS Algorithm counting of tumor stromal cells is reliable, accurate, and cost-effective.