Increased incidence of early de novo cancer in liver graft recipients treated with cyclosporine: an association with C2 monitoring and recipient age

Asian Pacific Association for the Study of the Liver clinical practice guidelines on liver transplantation

Liver transplantation is a highly complex and challenging field of clinical practice. Although it was originally developed in western countries, it has been further advanced in Asian countries through the use of living donor liver transplantation. This method of transplantation is the only available option in many countries in the Asia-Pacific region due to the lack of deceased organ donation. As a result of this clinical situation, there is a growing need for guidelines that are specific to the Asia-Pacific region. These guidelines provide comprehensive recommendations for evidence-based management throughout the entire process of liver transplantation, covering both deceased and living donor liver transplantation. In addition, the development of these guidelines has been a collaborative effort between medical professionals from various countries in the region. This has allowed for the inclusion of diverse perspectives and experiences, leading to a more comprehensive and effective set of guidelines.

Long Term Complications of Immunosuppression Post Liver Transplant

Improvement in immunosuppression has led to a remarkable improvement in short-term and long-term outcomes post-liver transplant (LT). However, with improvements in long-term survival, complications related to immunosuppressive drugs, either directly or indirectly, have also increased. The adverse events could be drug-specific, class-specific, or generic. Calcineurin inhibitors (cyclosporine and tacrolimus) are the backbone of the immunosuppression after LT and the main culprit associated with most of the complications, including renal failure, post-transplant diabetes mellitus (PTDM), and metabolic syndrome. Steroids are also implicated in the development of diabetes, osteoporosis, and metabolic syndrome post-LT. The development of infections and de novo malignancies (DNMs) is a generic effect linked to the overall cumulative immunosuppression. The development of these complications significantly hampers the quality of life and leads to increased morbidity and mortality post-LT. Thus, it is important to minimize the cumulative immunosuppression dose while simultaneously preventing allograft rejection. This review provides up-to-date, comprehensive knowledge of the complications of long-term immunosuppression post-LT along with associated risk factors and strategies to minimize the risk of complications.

Neoplastic Progression of Barrett's Esophagus Among Organ Transplant Recipients: a Retrospective Cohort Study

BACKGROUND

Several small studies reported high risk of progression to high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC) in Barrett's esophagus (BE) patients who undergo solid organ transplantation (SOT) and implied that this may be due to immunosuppressant use. However, the major shortcoming of these studies was the lack of a control population. Therefore, we aimed to determine the rates of neoplastic progression in BE patients who underwent SOT and compare to that in controls and identify the predictors of progression.

METHODS

This was a retrospective cohort study of BE patients seen in Cleveland Clinic and affiliated hospitals between January 2000 and August 2022. Demographics, endoscopic and histological findings, history of SOT and fundoplication, immunosuppressant use, and follow-up were abstracted.

RESULTS

The study population consisted of 3466 patients with BE, of which 115 had SOT (lung 35, liver 34, kidney 32, heart 14, and pancreas 2) and 704 patients on chronic immunosuppressants but no history of SOT. During a median follow-up of 5.1 years, there was no difference in the annual risk of progression between the three groups (SOT=0.61%, no SOT but on immunosuppressants= 0.82%, and no SOT/no immunosuppressants= 0.94%, p=0.72). On multivariate analysis, immunosuppressant use (odds ratio (OR) 1.38, 95% confidence interval (CI) 1.04-1.82, p=0.025) but not SOT (OR 0.39, 95%CI 0.15-1.01, p=0.053) was associated with neoplastic progression in BE patients.

CONCLUSION

Immunosuppression is a risk factor for progression of BE to HGD/EAC. Therefore, close surveillance of BE patients on chronic immunosuppressants needs to be considered.

Main factors influencing long-term outcomes of liver transplantation in 2022

Liver transplant (LT) outcomes have markedly improved in the recent decades, even if long-term morbidity and mortality are still considerable. Most of late deaths are independent from graft function and different comorbidities, including complications of metabolic syndrome and de novo neoplasms, seem to play a key role in determining long-term outcomes in LT recipients. This review discusses the main factors associated with late mortality and suggests possible strategies to improve long-term management and follow-up after liver transplantation. In particular, the reduction of drug toxicity, the use of tools to identify high-risk patients, and setting up a multidisciplinary team also for long-term management of LT recipients may further improve survival after liver transplantation.

mTORi-based immunosuppression reduces HCC recurrence at the expense of increased adverse side effects: A systematic review and meta-analysis

Sirolimus and everolimus are mammalian target of rapamycin inhibitors (mTORi) that can reduce relapse rates following liver transplantation (LT) for hepatocellular carcinoma (HCC). Herein, we performed a systematic review and meta-analysis to investigate the efficacy of mTORi and calcineurin inhibitors (CNI) in reducing HCC recurrence and survival adverse effects (AEs) in HCC patients after LT. Systematic literature searches were conducted using MEDLINE, EMBASE, and Cochrane Library databases up to October 2021. The primary outcomes of interest were tumor recurrence rates and overall survival. The secondary outcomes were the characterization and incidence of AEs. A total of 38 trials involving 10,607 participants was included in the analysis. The incidence of recurrence and overall mortality was significantly lower in the mTORi than in the CNI group (relative ratio [RR]: .78, 95% confidence interval [CI]: .68-.89 and RR: .76, 95% CI: .67-.86, respectively). The incidence of some AEs and complications such as acne, anemia, abnormal healing, dyslipidemia, depression, diarrhea, edema, headache/migraine, hypercholesterolemia, incisional hernia, infection, leukopenia, mouth ulceration, pyrexia, proteinuria, pruritis, rash, and thrombocytopenia were higher in the mTORi than in the CNI group. mTORi reduced the recurrence incidence and overall 5-year mortality rate but increased many other incidences of AEs compared with that by CNI. Therefore, clinicians should be aware of the risks and benefits of mTORi use when managing patients undergoing LT for HCC.

Melanoma risk during immunomodulating treatment

Immunosuppressive therapy is standard for the treatment of inflammatory diseases and for minimizing rejection in transplant patients. However, immunosuppressant drugs are associated with an increased risk of certain cancers. In particular, melanoma is an immunogenic tumor and as such, is strongly influenced by the immune system. We performed this literature review to summarize the effects of commonly used immunomodulating agents on melanoma development, recurrence and progression. We outline the mechanism of action of each drug and discuss the available evidence on its influence on melanoma. Based on existing literature, we recommend avoiding the following agents in patients with a history of invasive melanoma: cyclosporine, sirolimus, natalizumab, IL-6 inhibitors, cyclophosphamide, methotrexate and the tumor necrosis factor-alpha inhibitors infliximab and etanercept. If there are no viable alternative agents, we recommend for these patients to see a dermatologist every 6 months for a thorough skin examination.

Cumulative incidence of solid and hematological De novo malignancy after liver transplantation in a multicentre cohort

BACKGROUND

Recent innovations in the field of liver transplantation have led to a wealth of new treatment regimes, with potential impact on the onset of de novo malignancies (DNM). The aim of this multicenter cohort study was to provide contemporary figures for the cumulative incidences of solid and hematological DNM after liver transplantation.

METHODS

We designed a retrospective cohort study including patients undergoing LT between 2000 and 2015 in three Italian transplant centers. Cumulative incidence was calculated by Kaplan-Meyer analysis.

RESULTS

The study included 789 LT patients with a median follow-up of 81 months (IQR: 38-124). The cumulative incidence of non-cutaneous DNM was 6.2% at 5-years, 11.6% at 10-years and 16.3% at 15-years. Post-Transplant Lymphoproliferative Disorders (PTLD) were demonstrated to have a cumulative incidence of 1.0% at 5-years, 1.6% at 10-years and 2.2% at 15-years. Solid Organ Tumors (SOT) demonstrated higher cumulative incidences - 5.3% at 5-years, 10.3% at 10-years and 14.4% at 15-years. The most frequently observed classifications of SOT were lung (rate 1.0% at 5-years, 2.5% at 10-years) and head & neck tumors (rate 1.3% at 5-years, 1.9% at 10-years).

CONCLUSIONS

Lung tumors and head & neck tumors are the most frequently observed SOT after LT.

De Novo Malignancy After Liver Transplantation: Risk Assessment, Prevention, and Management-Guidelines From the ILTS-SETH Consensus Conference

De novo malignancies (DNMs) following liver transplantation (LT) have been reported as 1 of the major causes of late mortality, being the most common cause of death in the second decade after LT. The overall incidence of DNMs is reported to be in the range of 3.1% to 14.4%, and the incidence is 2- to 3-fold higher in transplant recipients than in age- and sex-matched healthy controls. Long-term immunosuppressive therapy, which is the key in maintaining host tolerance and achieving good long-term outcomes, is known to contribute to a higher risk of DNMs. However, the incidence and type of DNM also depends on different risk factors, including patient demographics, cause of the underlying chronic liver disease, behavior (smoking and alcohol abuse), and pre-existing premalignant conditions. The estimated standardized incidence ratio for different DNMs is also variable. The International Liver Transplantation Society-Spanish Society of Liver Transplantation Consensus Conference working group on DNM has summarized and discussed the current available literature on epidemiology, risk factors, management, and survival after DNMs. Recommendations for screening and surveillance for specific tumors, as well as immunosuppression and cancer-specific management in patients with DNM, are summarized.

Advances in liver transplantation for unresectable colon cancer liver metastasis

It is estimated that 50% of patients with colorectal cancer will develop liver metastasis. Surgical resection significantly improves survival and provides a chance of cure for patients with colorectal cancer liver metastasis (CRLM). Increasing the resectability of primary unresectable liver metastasis provides more survival benefit for those patients. Considerable surgical innovations have been made to increase the resection rate and decrease the potential risk of hepatic failure postoperation. Liver transplantation (LT) has been explored as a potential curative treatment for unresectable CRLM. However, candidate selection criteria, chemotherapy strategies, refined immunity regimens and resolution for the shortage of grafts are lacking. This manuscript discusses views on surgical indication, peritransplantation anti-tumor and anti-immunity therapy and updated advances in LT for unresectable CRLM. A literature review of published articles and registered clinical trials in PubMed, Google Scholar, and Clinicaltrials.gov was performed to identify studies related to LT for CRLM. Some research topics were identified, including indications for LT for CRLM, oncological risk, antitumor regimens, graft loss, administration of anti-immunity drugs and solutions for graft deficiency. The main candidate selection criteria are good patient performance, good tumor biological behavior and chemosensitivity. Chemotherapy should be administered before transplantation but is not commonly administered posttransplantation for preventive purposes. Mammalian target of rapamycin regimens are recommended for their potential oncological benefit, although there are limited cases. In addition to extended criterion grafts, living donor grafts and small grafts combined with two-stage hepatectomy are efficient means to resolve organ deficiency. LT has been proven to be an effective treatment for selected patients with liver-only CRLM. Due to limited donor grafts, high cost and poorly clarified oncological risks, LT for unresectable CRLM should be strictly performed under a well-organized study plan in selected patients. Some vital factors, like LT indication and anti-tumor and anti-immune treatment, remain to be confirmed. Ongoing clinical trials are expected to delineate these topics.

De Novo Carcinoma after Solid Organ Transplantation to Give Insight into Carcinogenesis in General-A Systematic Review and Meta-Analysis

Simple Summary

Patients receiving a solid organ transplantation, such as a kidney, liver, or lung transplantation, inevitably have to take drugs to suppress the immune system in order to prevent rejection of the transplanted organ. However, these drugs are known to cause malignancies in the long term. This study focuses specifically on newly developed carcinomas in patients who use those drugs after a solid organ transplantation. This systematic review and meta-analysis of published data show a 20-fold risk to develop a carcinoma after solid organ transplantation compared to the general population, with specifically increased risks in patients who receive cyclosporine or azathioprine. By comparing the different pathways involved in immunosuppression and the occurrence of carcinoma development, new insights can be discovered for future research and understanding of carcinoma development in transplantation patients and the general population as well.

Abstract

Immunosuppressive therapy after solid organ transplantation leads to the development of cancer in many recipients. Analysis of the occurrence of different types of de novo carcinomas in relation to specific immunosuppressive drugs may give insight into their carcinogenic process and carcinogenesis in general. Therefore, a systematic search was performed in Embase and PubMed. Studies describing over five de novo carcinomas in patients using immunosuppressive drugs after solid organ transplantation were included. Incidence per 1000 person-years was calculated with DerSimonian–Laird random effects model and odds ratio for developing carcinomas with the Mantel–Haenszel test. Following review of 5606 papers by title and abstract, a meta-analysis was conducted of 82 studies. The incidence rate of de novo carcinomas was 8.41. Patients receiving cyclosporine developed more de novo carcinomas compared to tacrolimus (OR1.56, 95%CI 1.00–2.44) and mycophenolate (OR1.26, 95%CI 1.03–1.56). Patients receiving azathioprine had higher odds to develop de novo carcinomas compared to mycophenolate (OR3.34, 95%CI 1.29–8.65) and head and neck carcinoma compared to tacrolimus (OR3.78, 95%CI 1.11–12.83). To conclude, patients receiving immunosuppressive drugs after solid organ transplantation have almost a 20-fold increased likelihood of developing carcinomas, with the highest likelihood for patients receiving cyclosporine A and azathioprine. Looking into altered immune pathways affected by immunosuppressive drugs might lead to better understanding of carcinogenesis in general.

Suppression of Hepatocellular Carcinoma by Mycophenolic Acid in Experimental Models and in Patients

BACKGROUND

Tumor recurrence is a major complication following liver transplantation (LT) as treatment for hepatocellular carcinoma (HCC). Immunosuppression is an important risk factor for HCC recurrence, but conceivably may depend on the type of immunosuppressive medication. Mycophenolic acid (MPA) is a currently widely used immunosuppressant. This study investigated the effects of MPA on HCC.

METHODS

Three human HCC cell lines and organoids from mouse primary liver tumor were used as experimental models. MTT, Alamar Blue assay, cell cycle analysis, colony formation, and [3H]-thymidine assays were performed. An LT database was used for retrospective analysis of the effect of mycophenolate mofetil, the prodrug of MPA, on HCC recurrence.

RESULTS

With clinically achievable concentrations, MPA effectively inhibited HCC cell proliferation and single-cell colony-forming unit. In short-term experiments, MPA effectively elicited S phase arrest in HCC cell lines. In addition, the initiation and growth of liver tumor organoids were effectively inhibited by MPA. Most importantly, the use of mycophenolate mofetil in patients with HCC-related LT was significantly associated with less tumor recurrence and improved patient survival.

CONCLUSIONS

MPA can specifically counteract HCC growth in vitro and tumor recurrence in LT patients. These results warrant prospective clinical trials into the role of MPA-mediated immunosuppression following LT of patients with HCC.

Immunosuppressive drug withdrawal late after liver transplantation improves the lipid profile and reduces infections

BACKGROUND

Treatment with immunosuppressive drugs (IS) after transplantation is accompanied by severe side effects. A limited number of studies have investigated the effect of IS withdrawal on IS-related comorbidities after liver transplantation (LTx) and the results are contradictory.

PATIENTS AND METHODS

We determined in a retrospective case-control study the clinical effects of complete IS withdrawal in operationally tolerant (TOL) LTx recipients who discontinued IS 10.8 ± 5.1 years after LTx (n = 13) compared with a completely matched control (CTRL) group with a regular IS regimen (n = 22). TOL recipients have been IS and rejection free for 4.0 ± 2.8 years.

RESULTS

IS withdrawal in TOL recipients resulted in lower low-density lipoprotein levels (P = 0.027), whereas this was not observed in the CTRL group. Furthermore, persistent infections in individual recipients were resolved successfully by IS withdrawal. TOL recipients also had significantly fewer de novo infections after IS withdrawal (TOL pre vs. post withdrawal P = 0.0247) compared with recipients continued on IS during the same follow-up period (post withdrawal TOL vs. CTRL P = 0.044). Unfortunately, no improvement in kidney function, and lower rates of de novo occurrences of diabetes, hypertension, cardiovascular diseases, and malignancies were observed in the TOL group after IS withdrawal compared with the CTRL group during the same follow-up time period.

CONCLUSION

IS withdrawal late after LTx reduces infection rates and low-density lipoprotein levels, but other IS-related side effects persist late after LTx. An accurate tolerance immune profile enabling identification of tolerant LTx recipients eligible for safe IS withdrawal earlier after transplantation is needed to prevent the development of irreversible IS-related side effects.

Alloresponses of Mixed Lymphocyte Hepatocyte Culture to Immunosuppressive Drugs as an In-Vitro Model of Hepatocyte Transplantation

Background

Hepatocyte transplantation (HCTx) has the potential for the treatment of end-stage liver disease. However, failure of engraftment and the long-term acceptance of cellular allografts remain significant challenges for its clinical application. The aim of this study was to investigate the efficacy of the immunosuppressive agents, Cyclosporine, Everolimus, and Belatacept to suppress the alloresponse of primary human hepatocytes in a mixed lymphocyte-hepatocyte culture (MLHC) and their potential hepatotoxicity in vitro.

Material/Methods

Primary human hepatocytes were co-cultured with allogeneic peripheral blood mononuclear cells (PBMCs) in an MLHC. Proliferative alloresponses were determined by flow cytometry, and cytokine secretion was measured using Luminex-based multiplex technology. Using an MLHC, the alloresponses of primary human hepatocytes were compared in the presence and absence of Cyclosporine, Everolimus, and Belatacept. Cultured primary human hepatocytes were assessed for the production of albumin, urea, aspartate transaminase (AST) and DNA content. Metabolic activity was determined with the MTT assay.

Results

Immune responses induced by primary human hepatocytes were effectively suppressed by Cyclosporine, Everolimus, and Belatacept. Everolimus significantly reduced the metabolic activity of primary human hepatocytes in vitro, suggesting impairment of cell viability. However, further functional analysis showed no significant differences between treated and untreated controls.

Conclusions

Cyclosporine, Everolimus, and Belatacept suppressed the alloresponse of primary human hepatocytes in an MLHC without significant cytotoxicity or functional cell impairment.

Dissecting the Multiplicity of Immune Effects of Immunosuppressive Drugs to Better Predict the Risk of de novo Malignancies in Solid Organ Transplant Patients

De novo malignancies constitute an emerging cause of morbidity after solid organ transplant (SOT), significantly affecting the long-term survival of transplant recipients. Pharmacologic immunosuppression may functionally impair the immunosurveillance in these patients, thereby increasing the risk of cancer development. Nevertheless, the multiplicity and heterogeneity of the immune effects induced by immunosuppressive drugs limit the current possibilities to reliably predict the risk of de novo malignancy in SOT patients. Therefore, there is the pressing need to better characterize the immune dysfunctions induced by the different immunosuppressive regimens administered to prevent allograft rejection to tailor more precisely the therapeutic schedule and decrease the risk of de novo malignancies. We herein highlight the impact exerted by different classes of immunosuppressants on the most relevant immune cells, with a particular focus on the effects on dendritic cells (DCs), the main regulators of the balance between immunosurveillance and tolerance.

Recurrence of Hepatitis B Infection in Liver Transplant Patients Receiving Long-Term Hepatitis B Immunoglobulin Prophylaxis

BACKGROUND Long-term real-world data are relatively sparse regarding recurrence of chronic hepatitis B virus (HBV) infection after liver transplantation using hepatitis B immunoglobulin (HBIg) and nucleos(t)ide analogue (NUC) prophylaxis. MATERIAL AND METHODS Data from 371 adults transplanted for HBV-related disease at 20 European centers and given HBIg for ³12 months ± NUC therapy were analyzed retrospectively. RESULTS HBIg comprised Hepatect® (iv HBIgB; n=299), subcutaneous Zutectra® (sc HBIg, n=236), and other HBIg preparations (n=130); 93.5% received NUC therapy. Mean follow-up was 6.8±3.5 years. The primary efficacy variable, freedom from HBV recurrence, occurred in 95.7% of patients (95% CI [93.1%, 97.5%]). The observed incidence of recurrence was 16/371 (4.3%) (annual rate 0.65%); 5/16 patients with recurrence had discontinued HBIg and 7/16 had anti-HBs <100 IU/l. Excluding these 7 patients, the HBV recurrence rate was 2.4%. The recurrence rate while on HBIg therapy was 1 per 2069 months. In patients who discontinued HBIg, risk of HBV recurrence versus sc HBIg users was increased by 5.2-fold (1 per 1 603 versus 1 per 8379 treatment months). The annual rate of HBV-related hepatocellular carcinoma (HCC) recurrence was 1.7%. CONCLUSIONS These results support the long-term use of HBIg with NUC therapy as an effective management strategy to minimize risk of HBV recurrence and virus-related complications after liver transplantation.

Ab initio Everolimus-based Versus Standard Calcineurin Inhibitor Immunosuppression Regimen in Liver Transplant Recipients

AIM

We designed a retrospective case-control study to determine the efficacy and feasibility of everolimus (EVR) combined with low-dose tacrolimus (Tac) ab initio versus standard-dose Tac after liver transplantation (LT).

METHODS

Seventy-one adult LT patients, receiving EVR and low-dose Tac without corticosteroids or induction therapy from postoperative day 1 (EVR group) were compared with a well-matched control group of 61 recipients treated with standard-dose Tac in association with antimetabolite.

RESULTS

Baseline characteristics for the two groups were comparable. The overall patient and graft survival rates were similar (P = .908). Liver function was stable during the follow-up. In the EVR group, biopsy-proven acute rejection occurred in two cases (2.8%), whereas chronic rejection occurred in one (1.4%). The EVR group experienced a better renal function already after 2 weeks (estimated glomerular filtration rate: 89.85 [36.46 to 115.3] mL/min/1.73 m² vs. 68.77 [16.11 to 115.42] mL/min/1.73 m²; P = .013), which was also observed after a median time of 27 months (range, 0 to 82 months) from LT (estimated glomerular filtration rate: 80 [45 to 118.3] mL/min/1.73 m² vs. 70.9 [45 to 88.4] mL/min/1.73 m²; P = .04). After a median time of 27 months, the EVR group showed lower incidence of arterial hypertension and insulin-dependent diabetes mellitus.

CONCLUSION

Ab initio EVR-based immunosuppression could be a valid option immediately after surgery in recipients at high-risk for post-LT renal impairment.

The 28-year incidence of de novo malignancies after liver transplantation: A single-center analysis of risk factors and mortality in 1616 patients

De novo malignancies (DNMs) are one of the leading causes of late mortality after liver transplantation (LT). We analyzed 1616 consecutive patients who underwent LT between 1988 and 2006 at our institution. All patients were prospectively observed over a study period of 28 years by our own outpatient clinic. Complete follow-up data were available for 96% of patients, 3% were incomplete, and only 1% were lost to follow-up. The median follow-up of the patients was 14.1 years. Variables with possible prognostic impact on the development of DNMs were analyzed, as was the incidence of malignancies compared with the nontransplant population by using standardized incidence ratios. In total, 266 (16.5%) patients developed 322 DNMs of the following subgroups: hematological malignancies (n = 49), skin cancer (n = 83), and nonskin solid organ tumors (SOT; n = 190). The probability of developing any DNM within 10 and 25 years was 12.9% and 23.0%, respectively. The respective probability of developing SOT was 7.8% and 16.2%. Mean age at time of diagnosis of SOT was 57.4 years (range, 18.3-81.1 years). In the multivariate analysis, an increased recipient age (hazard ratio [HR], 1.03; P < 0.001) and a history of smoking (HR, 1.92; P < 0.001) were significantly associated with development of SOT. Moreover, the development of SOT was significantly increased in cyclosporine A-treated compared with tacrolimus-treated patients (HR, 1.53; P = 0.03). The present analysis shows a disproportionate increase of de novo SOT with an increasing follow-up period. Increased age and a history of smoking are confirmed as major risk factors. Moreover, the importance of immunosuppression is highlighted. Liver Transplantation 23 1404-1414 2017 AASLD.

Delayed and short course of rapamycin prevents organ rejection after allogeneic liver transplantation in rats

AIM

To test whether a delayed and short course of rapamycin would induce immunosuppressive effects following allogeneic orthotopic liver transplantation (OLT) in rats.

METHODS

Allogeneic OLTs were performed using Dark Agouti livers transplanted into Lewis recipients, and syngeneic OLTs were performed using the Lewis rat strain. Rapamycin (1 mg/kg per day) was administered by gavage from day 4 to day 11 post-transplantation. Lymphocyte cellular compartments were analyzed by flow cytometry in draining lymph nodes, non-draining lymph nodes and the spleen at days 11 and 42 in rapamycin-treated rats, untreated control rats and syngeneic grafted rats. Skin grafts from Dark agouti or from F344 RT were performed at day 30 on liver grafted rats treated with rapamycin.

RESULTS

An 8-d course of rapamycin treatment initiated 4 d following transplantation resulted in the survival of grafted rats for more than 100 d. In contrast, untreated rats died of liver failure within 13 to 21 d. The analysis of the cellular compartment revealed an increase in two cellular subpopulations, specifically myeloid-derived suppressor cells (MDSCs) and CD8⁺CD45RC^low T cells, without major modifications in the regulatory T cell (Treg) compartment in treated rats in the early stages after grafting. We evaluated the ability of treated rats to reject third-party allogeneic skin grafts to confirm their immune competence. In contrast, when skin was collected from rats syngeneic to the grafted liver, it was not rejected.

CONCLUSION

Our results demonstrate that short and delayed rapamycin treatment allows for tolerance in allogeneic OLT. The results also allowed for the identification of the mechanisms of tolerance induced by rapamycin by identifying MDSCs and CD8⁺CD45RC^low T cells as associated with the state of tolerance.

Risk Factors and Outcomes of De Novo Cancers (Excluding Nonmelanoma Skin Cancer) After Liver Transplantation for Primary Sclerosing Cholangitis

BACKGROUND

Patients with primary sclerosing cholangitis (PSC) may be at higher risk of malignancy after liver transplantation (LT) compared to other LT recipients. We aimed to determine the cumulative incidence of/risk factors for long-term cancer-related mortality in patients with PSC after LT.

METHODS

All adult patients underwent LT for PSC without cholangiocarcinoma from 1984 to 2012, with follow-up through June 2015. We estimated cumulative incidence, risk factors, and mortality from de novo malignancies after LT.

RESULTS

Two hundred ninety-three patients were identified (mean [SD] age, 47 [12] years; 63.3% males; 2.4% smoking at LT). Over a median of 11.5 years (range, 6.4-18.6 years), 64 patients (21.8%) developed 73 nonskin cancers, including 46 solid-organ cancers (renal, 11; colorectal, 11; prostate, 7; breast, 5; pancreas, 5; ovarian/endometrial/vulvar cancers, 3; and de novo cholangiocarcinoma, 4). Twenty-two patients developed hematologic malignancies (posttransplant lymphoproliferative diseases, 18; Hodgkin disease, 2; and myelodysplastic syndrome, 2). Five patients developed melanoma. The 1-, 5-, 10-, and 20-year cumulative incidences of cancer were 2.1%, 8.6%, 18.7%, and 27%, respectively. Mortality of patients with PSC who developed cancer was higher than that of patients with PSC without cancer (hazard ratio, 2.2; P < 0.01). On multivariate analysis, recipient's age and elevated pre-LT international normalized ratio were associated with increased risk of de novo (nonskin) malignancy.

CONCLUSION

The 10-year cumulative risk of cancer after LT for advanced-stage PSC was 18.7%, with posttransplant lymphoproliferative diseases, colorectal cancer, and renal cell cancer being the most common. Post-LT de novo nonskin cancer decreased overall posttransplant survival. Only recipient's age and elevated international normalized ratio at LT were associated with increased nonskin cancer risk.

Use of Everolimus in Liver Transplantation: Recommendations From a Working Group

Immunosuppression after liver transplantation (LT) is presently based on use of calcineurin inhibitors (CNI), although they are associated with an increased incidence of renal dysfunction, cardiovascular complications, and de novo and recurrent malignancies. Over the past decade, mammalian target of rapamycin inhibitors have received considerable attention as immunosuppressants because they are associated with a more favorable renal profile versus CNI, as well as antiproliferative activity in clinical studies. Comprehensive guidelines on use of everolimus (EVR) in LT are still lacking. In Italy, a project, named Everolimus: the road to long-term functioning, was initiated to collect the experience on EVR after LT with the aim of providing guidance for transplant clinicians. Herein, recommendations by this national consensus group, based on Delphi methodology, are presented. Consensus was reached on 20 of the 23 statements proposed, and their level of evidence, grade of recommendation, and percent of agreement are reported. Statements are grouped into 4 areas: (A) renal function; (B) time of EVR introduction, CNI reduction and elimination, and risk for graft rejection; (C) antiproliferative effects of EVR; and (D) management of EVR-related adverse events. The high level of consensus shows that there is good agreement on the routine use of EVR in predefined clinical scenarios, especially in light of posttransplant nephrotoxicity and other adverse events associated with long-term administration of CNIs.

The authors summarize the recommendations reached by an Italian National Consensus group using the Delphi methodology on the use of everolimus in liver transplantation, particularly its role in renal function, antiproliferative effects, adverse events, timing of introduction, and rejection risk.

Practical Recommendations for Long-term Management of Modifiable Risks in Kidney and Liver Transplant Recipients: A Guidance Report and Clinical Checklist by the Consensus on Managing Modifiable Risk in Transplantation (COMMIT) Group

Short-term patient and graft outcomes continue to improve after kidney and liver transplantation, with 1-year survival rates over 80%; however, improving longer-term outcomes remains a challenge. Improving the function of grafts and health of recipients would not only enhance quality and length of life, but would also reduce the need for retransplantation, and thus increase the number of organs available for transplant. The clinical transplant community needs to identify and manage those patient modifiable factors, to decrease the risk of graft failure, and improve longer-term outcomes.COMMIT was formed in 2015 and is composed of 20 leading kidney and liver transplant specialists from 9 countries across Europe. The group's remit is to provide expert guidance for the long-term management of kidney and liver transplant patients, with the aim of improving outcomes by minimizing modifiable risks associated with poor graft and patient survival posttransplant.The objective of this supplement is to provide specific, practical recommendations, through the discussion of current evidence and best practice, for the management of modifiable risks in those kidney and liver transplant patients who have survived the first postoperative year. In addition, the provision of a checklist increases the clinical utility and accessibility of these recommendations, by offering a systematic and efficient way to implement screening and monitoring of modifiable risks in the clinical setting.

Tolerance in liver transplantation: Biomarkers and clinical relevance

Transplantation is the optimal treatment for end-stage organ failure, and modern immunosuppression has allowed important progress in short-term outcomes. However, immunosuppression poorly influences chronic rejection and elicits chronic toxicity in current clinical practice. Thus, a major goal in transplantation is to understand and induce tolerance. It is well established that human regulatory T cells expressing the transcription factor FoxP3 play important roles in the maintenance of immunological self-tolerance and immune homeostasis. The major regulatory T cell subsets and mechanisms of expansion that are critical for induction and long-term maintenance of graft tolerance and survival are being actively investigated. Likewise, other immune cells, such as dendritic cells, monocyte/macrophages or natural killer cells, have been described as part of the process known as "operational tolerance". However, translation of these results towards clinical practice needs solid tools to identify accurately and reliably patients who are going to be tolerant. In this way, a plethora of genetic and cellular biomarkers is raising and being validated worldwide in large multi-center clinical trials. Few of the studies performed so far have provided a detailed analysis of the impact of immunosuppression withdrawal on pre-existing complications derived from the long-term administration of immunosuppressive drugs and the side effects associated with them. The future of liver transplantation is aimed to develop new therapies which increase the actual low tolerant vs non-tolerant recipients ratio.

Independent Pre-Transplant Recipient Cancer Risk Factors after Kidney Transplantation and the Utility of G-Chart Analysis for Clinical Process Control

Background

The aim of this study is to identify independent pre-transplant cancer risk factors after kidney transplantation and to assess the utility of G-chart analysis for clinical process control. This may contribute to the improvement of cancer surveillance processes in individual transplant centers.

Patients and Methods

1655 patients after kidney transplantation at our institution with a total of 9,425 person-years of follow-up were compared retrospectively to the general German population using site-specific standardized-incidence-ratios (SIRs) of observed malignancies. Risk-adjusted multivariable Cox regression was used to identify independent pre-transplant cancer risk factors. G-chart analysis was applied to determine relevant differences in the frequency of cancer occurrences.

Results

Cancer incidence rates were almost three times higher as compared to the matched general population (SIR = 2.75; 95%-CI: 2.33–3.21). Significantly increased SIRs were observed for renal cell carcinoma (SIR = 22.46), post-transplant lymphoproliferative disorder (SIR = 8.36), prostate cancer (SIR = 2.22), bladder cancer (SIR = 3.24), thyroid cancer (SIR = 10.13) and melanoma (SIR = 3.08). Independent pre-transplant risk factors for cancer-free survival were age <52.3 years (p = 0.007, Hazard ratio (HR): 0.82), age >62.6 years (p = 0.001, HR: 1.29), polycystic kidney disease other than autosomal dominant polycystic kidney disease (ADPKD) (p = 0.001, HR: 0.68), high body mass index in kg/m² (p<0.001, HR: 1.04), ADPKD (p = 0.008, HR: 1.26) and diabetic nephropathy (p = 0.004, HR = 1.51). G-chart analysis identified relevant changes in the detection rates of cancer during aftercare with no significant relation to identified risk factors for cancer-free survival (p<0.05).

Conclusions

Risk-adapted cancer surveillance combined with prospective G-chart analysis likely improves cancer surveillance schemes by adapting processes to identified risk factors and by using G-chart alarm signals to trigger Kaizen events and audits for root-cause analysis of relevant detection rate changes. Further, comparative G-chart analysis would enable benchmarking of cancer surveillance processes between centers.

Incidence, risk factors and outcomes of de novo malignancies post liver transplantation

Liver transplantation (LT) is associated with a 2 to 7 fold higher, age and gender adjusted, risk of de novo malignancy. The overall incidence of de novo malignancy post LT ranges from 2.2% to 26%, and 5 and 10 years incidence rates are estimated at 10% to 14.6% and 20% to 32%, respectively. The main risk factors for de novo malignancy include immunosuppression with impaired immunosurveillance, and a number of patient factors which include; age, latent oncogenic viral infections, tobacco and alcohol use history, and underlying liver disease. The most common cancers after LT are non-melanoma skin cancers, accounting for approximately 37% of de novo malignancies, with a noted increase in the ratio of squamous to basal cell cancers. While these types of skin cancer do not impact patient survival, post-transplant lymphoproliferative disorders and solid organ cancer, accounting for 25% and 48% of malignancies, are associated with increased mortality. Patients developing these types of cancer are diagnosed at more advanced stages, and their cancers behave more aggressively compared with the general population. Patients undergoing LT for primary sclerosing cholangitis (particularly with inflammatory bowel disease) and alcoholic liver disease have high rates of malignancies compared with patients undergoing LT for other indications. These populations are at particular risk for gastrointestinal and aerodigestive cancers respectively. Counseling smoking cessation, skin protection from sun exposure and routine clinical follow-up are the current approach in practice. There are no standardized surveillance protocol, but available data suggests that regimented surveillance strategies are needed and capable of yielding cancer diagnosis at earlier stages with better resulting survival. Evidence-based strategies are needed to guide optimal surveillance and safe minimization of immunosuppression.

Progression of Incidental Intraductal Papillary Mucinous Neoplasms of the Pancreas in Liver Transplant Recipients

OBJECTIVES

Intraductal papillary mucinous neoplasms (IPMNs) are premalignant pancreatic cysts commonly found incidentally. Immunosuppression accelerates carcinogenesis.Thus, we aimed to compare IPMN progression in liver transplant (LT) recipients on chronic immunosuppression to progression among an immunocompetent population.

METHODS

We retrospectively assessed adult LT recipients between 2008 and 2014 for imaging evidence of IPMN. Diagnosis of IPMN was based on history, imaging, and cyst fluid analysis. The immunocompetent control group consisted of nontransplant patients from our pancreatic cyst surveillance program with IPMN under surveillance for greater than 12 months between 1997 and 2013. Four hundred fifty-four patients underwent LT in the study period and had cross-sectional imaging.

RESULTS

The prevalence of suspected IPMN was 6.6% (30 of 454). Compared with 131 controls, the transplant cohort was younger, with increased prevalence of diabetes and smoking. The prevalence of other risk factors for IPMN progression (history of pancreatitis, family history of pancreatic cancer) was similar. After an average follow-up of 31 months, most cysts increased in diameter, with a similar increase of dominant cyst (0.4 cm vs 0.5 cm; P = 0.6). Type of immunosuppression was not associated with the increased rate of cyst growth.

CONCLUSIONS

Our findings suggest that LT recipients with incidental IPMN can be managed under similar guidelines as immunocompetent patients.

Immunosuppressive potency of mechanistic target of rapamycin inhibitors in solid-organ transplantation

Mammalian target of rapamycin, also known as mechanistic target of rapamycin (mTOR) is a protein kinase that belongs to the PI3K/AKT/mTOR signaling pathway, which is involved in several fundamental cellular functions such as cell growth, proliferation, and survival. This protein and its associated pathway have been implicated in cancer development and the regulation of immune responses, including the rejection response generated following allograft transplantation. Inhibitors of mTOR (mTORi) such as rapamycin and its derivative everolimus are potent immunosuppressive drugs that both maintain similar rates of efficacy and could optimize the renal function and diminish the side effects compared with calcineurin inhibitors. These drugs are used in solid-organ transplantationtoinduceimmunosuppression while also promoting the expansion of CD4+CD25+FOXP3+ regulatory T-cells that could favor a scenery of immunological tolerance. In this review, we describe the mechanisms by which inhibitors of mTOR induce suppression by regulation of these pathways at different levels of the immune response. In addition, we particularly emphasize about the main methods that are used to assess the potency of immunosuppressive drugs, highlighting the studies carried out about immunosuppressive potency of inhibitors of mTOR.

Neoplastic disease after liver transplantation: Focus on de novo neoplasms

De novo neoplasms account for almost 30% of deaths 10 years after liver transplantation and are the most common cause of mortality in patients surviving at least 1 year after transplant. The risk of malignancy is two to four times higher in transplant recipients than in an age- and sex-matched population, and cancer is expected to surpass cardiovascular complications as the primary cause of death in transplanted patients within the next 2 decades. Since exposure to immunosuppression is associated with an increased frequency of developing neoplasm, long-term immunosuppression should be therefore minimized. Promising results in the prevention of hepatocellular carcinoma (HCC) recurrence have been reported with the use of mTOR inhibitors including everolimus and sirolimus and the ongoing open-label prospective randomized controlled SILVER. Study will provide more information on whether sirolimus-containing vs mTOR-inhibitor-free immunosuppression is more efficacious in reducing HCC recurrence.

Incidence, risk factors and outcome of de novo tumors in liver transplant recipients focusing on alcoholic cirrhosis

Orthotopic liver transplantation (OLT) is an established life-saving procedure for alcoholic cirrhotic (AC) patients, but the incidence of de novo tumors ranges between 2.6% and 15.7% and is significantly increased in comparison with patients who undergo OLT for other etiologies. Tobacco, a known carcinogen, has been reported to be between 52% and 83.3% in AC patients before OLT. Other risk factors that contribute to the development of malignancies are dose-dependent immunosuppression, advanced age, viral infections, sun exposure, and premalignant lesions (inflammatory bowel disease, Barrett’s esophagus). A significantly more frequent incidence of upper aerodigestive (UAD) tract, lung, skin, and kidney-bladder tumors has been found in OLT recipients for AC in comparison with other etiologies. Liver transplant recipients who develop de novo non-skin tumors have a decreased long-term survival rate compared with controls. This significantly lower survival rate is more evident in AC recipients who develop UAD tract or lung tumors after OLT mainly because the diagnosis is usually performed at an advanced stage. All transplant candidates, especially AC patients, should be encouraged to cease smoking and alcohol consumption in the pre- and post-OLT periods, use skin protection, avoid sun exposure and over-immunosuppression, and have a yearly otopharyngolaryngeal exploration and chest computed tomography scan in order to prevent or reduce the incidence of de novo malignancies. Although still under investigation, substitution of calcineurin inhibitors for sirolimus or everolimus may reduce the incidence of de novo tumors after OLT.

The ins and outs of microRNAs as biomarkers in liver disease and transplantation

Ongoing research is being conducted in the field of transplantation to discover novel, noninvasive biomarkers for assessment of graft quality before transplantation and monitoring of graft injury after transplantation. MicroRNAs (miRNAs) are among the most promising in this field. MiRNAs are small noncoding RNAs that function as important regulators of gene expression in response to cellular stress and disease. An advantage that makes miRNAs attractive candidates for biomarker research is their fast release from cells in response to stress and injury, which can occur via different routes. In the context of liver transplantation (LT), noninvasive measurement and stability of extracellular miRNAs in blood, bile, and graft perfusates has been linked to cell-type specific injury and early graft outcome following LT. Furthermore, specific intrahepatic miRNA expression patterns have been associated with graft survival and recurrent disease, like hepatitis C virus-related fibrosis and hepatocellular carcinoma. Therefore, miRNAs with strong predictive value and high sensitivity and specificity might be successfully applied to assess hepatic injury and to diagnose (recurrent) liver disease before, during and after LT. In this review, the current features and future prospects of miRNAs as biomarkers in and out of the liver are discussed.

Conversion to everolimus dramatically improves the prognosis of de novo malignancies after liver transplantation for alcoholic liver disease

De novo malignancies are a main cause for late death after liver transplantation (LT). Everolimus (ERL) is an immunosuppressive agent with antitumoral properties. The aim of the present retrospective study was to identify prognostic factors, including conversion to ERL, for patients presenting non-cutaneous de novo solid organ malignancy after LT for alcoholic cirrhosis. The study population consisted of 83 patients (presenting 100 tumors, including 75% of upper aerodigestive tract cancers), among the 398 patients who underwent LT for alcoholic cirrhosis in our center. After diagnosis, ERL was introduced in 38 patients and calcineurin-inhibitor was discontinued in 64.1% of them. Tumor stage was a significant prognostic factor with a one-yr survival at 82.6% for early stages, 63.4% for intermediate stages (N+) and 27.4% for disseminated diseases (p < 0.001). Associated relative risk factor was 2.202 (95% CI 1.044-4.644) for intermediate stages and 5.743 (95% CI 2.436-13.541) for metastatic stages. One- and five-yr survival was 77.4% and 35.2% in ERL group vs. 47.2% and 19.4% in the non-ERL group, respectively (p = 0.003). The relative risk factor for ERL was 0.447 (95%CI 0.257-0.778). Our results strongly suggest that conversion to ERL improves the prognosis of de novo malignancies after LT for alcoholic cirrhosis. Prospective studies are needed to confirm this benefit.

The role of everolimus in liver transplantation

During the last 5 decades, liver transplantation has witnessed rapid development in terms of both technical and pharmacologic advances. Since their discovery, calcineurin inhibitors (CNIs) have remained the standard of care for immunosuppression therapy in liver transplantation, improving both patient and graft survival. However, adverse events, particularly posttransplant nephrotoxicity, associated with long-term CNI use have necessitated the development of alternate treatment approaches. These include combination therapy with a CNI and the inosine monophosphate dehydrogenase inhibitor mycophenolic acid and use of mammalian target of rapamycin (mTOR) inhibitors. Everolimus, a 40-O-(2-hydroxyethyl) derivative of mTOR inhibitor sirolimus, has a distinct pharmacokinetic profile. Several studies have assessed the role of everolimus in liver transplant recipients in combination with CNI reduction or as a CNI withdrawal strategy. The efficacy of everolimus-based immunosuppressive therapy has been demonstrated in both de novo and maintenance liver transplant recipients. A pivotal study in 719 de novo liver transplant recipients formed the basis of the recent approval of everolimus in combination with steroids and reduced-dose tacrolimus in liver transplantation. In this study, everolimus introduced at 30 days posttransplantation in combination with reduced-dose tacrolimus (exposure reduced by 39%) showed comparable efficacy (composite efficacy failure rate of treated biopsy-proven acute rejection, graft loss, or death) and achieved superior renal function as early as month 1 and maintained it over 2 years versus standard exposure tacrolimus. This review provides an overview of the efficacy and safety of everolimus-based regimens in liver transplantation in the de novo and maintenance settings, as well as in special populations such as patients with hepatocellular carcinoma recurrence, hepatitis C virus-positive patients, and pediatric transplant recipients. We also provide an overview of ongoing studies and discuss potential expansion of the role for everolimus in these settings.

Persistence of mild to moderate atopic dermatitis

IMPORTANCE

Atopic dermatitis (AD) is a common illness of childhood.

OBJECTIVE

To evaluate the natural history of AD and determine the persistence of symptoms over time.

DESIGN, SETTING, AND PARTICIPANTS

A cross-sectional and cohort study of a nation-wide long-term registry of children with AD enrolled in the Pediatric Eczema Elective Registry (PEER).

MAIN OUTCOMES AND MEASURES

Self-reported outcome of whether a child's skin was AD symptom-free for 6 months at 6-month intervals.

RESULTS

A total of 7157 patients were enrolled in the PEER study for a total of 22,550 person-years. At least 2 years of follow-up were observed for 4248 children and at least 5 years of follow-up were observed for 2416 children. Multiple demographic and exposure variables were associated with more persistent AD. At every age (ie, 2-26 years), more than 80% of PEER participants had symptoms of AD and/or were using medication to treat their AD. It was not until age 20 years that 50% of patients had at least 1 lifetime 6-month symptom- and treatment-free period.

CONCLUSIONS AND RELEVANCE

Based on this large longitudinal cohort study, symptoms associated with AD seem to persist well into the second decade of a child's life and likely longer. Atopic dermatitis is probably a life-long illness.

Optimal management of skin cancer in immunosuppressed patients

Skin cancer is the most common malignancy in humans with basal cell carcinoma representing the majority of cases in the general population. The prevalence of skin cancer is increased amongst immunosuppressed patients such as those with lymphoproliferative disorders including non-Hodgkin lymphoma and chronic lymphocytic leukemia or those with iatrogenic immunosuppression following organ transplantation. In addition, these patients experience greater morbidity and mortality associated with skin cancers. The most common skin cancer in immunosuppressed patients is squamous cell carcinoma, which often presents with more aggressive features and has a greater rate of metastasis. This article reviews the risk factors, etiology, clinical presentation, and prevalence of skin cancer amongst immunosuppressed patients, including organ transplant, lymphoproliferative disorders, autoimmune disorders, and human immunodeficiency virus. We also provide a comprehensive review of treatment guidelines for immunosuppressed patients with cutaneous malignancy. Surgical therapy is the cornerstone of treatment; however, we also discuss pharmacologic treatment options, lifestyle modifications, and revision of immunosuppressive regimens.

Liver transplantation: immunosuppression and oncology

PURPOSE OF REVIEW

Long-term survival of liver transplant recipients is threatened by increased rates of de-novo malignancy and recurrence of hepatocellular carcinoma (HCC), both events tightly related to immunosuppression.

RECENT FINDINGS

There is accumulating evidence linking increased exposure to immunosuppressants and carcinogenesis, particularly concerning calcineurin inhibitors (CNIs), azathioprine and antilymphocyte agents. A recent study including 219 HCC transplanted patients showed that HCC recurrence rates were halved if a minimization of CNIs was applied within the first month after liver transplant. With mammalian target of rapamycin (mTOR) inhibitors as approved immunosuppressants for liver transplant patients, pooled data from several retrospective studies have suggested their possible benefit for reducing HCC recurrence.

SUMMARY

Randomized controlled trials with sufficiently long follow-up are needed to evaluate the influence of different immunosuppression protocols in preventing malignancy after LT. Currently, early minimization of CNIs with or without mTOR inhibitors or mycophenolate seems a rational strategy for patients with risk factors for de-novo malignancy or recurrence of HCC after liver transplant. A deeper understanding of the immunological pathways of rejection and cancer would allow for designing more specific and safer drugs, and thus to prevent cancer after liver transplant.

The role of mammalian target of rapamycin inhibitors in the management of post-transplant malignancy

Post-transplant malignancies, which occur either de novo or as cancer recurrences, are due to chronic exposure to immunosuppressive agents and are often more aggressive than those that develop in the non-transplant setting. Mammalian target of rapamycin (mTOR) inhibitors have antitumor and immunosuppressive effects. The dual effects of this class of agents may provide adequate immunosuppression to prevent organ rejection while simultaneously reducing the risk of post-transplant malignancy. mTOR inhibitors have become established approved agents for treating renal cell carcinoma and other cancers and, as reviewed herein, accumulating experience among organ transplant recipients collectively points toward a potential to prevent the development of de novo malignancies of various types in the post-transplant period. To date, most research efforts surrounding mTOR inhibitors and cancer control in the transplant population have been in the area of skin cancer prevention, but there have also been interesting observations regarding regression of post-transplant Kaposi's sarcoma and post-transplantation lymphoproliferative disorder that warrant further study.

Rationale of personalized immunosuppressive medication for hepatocellular carcinoma patients after liver transplantation

Liver transplantation is the only potentially curative treatment for hepatocellular carcinoma (HCC) that is not eligible for surgical resection. However, disease recurrence is the main challenge to the success of this treatment. Immunosuppressants that are universally used after transplantation to prevent graft rejection could potentially have a significant impact on HCC recurrence. Nevertheless, current research is exclusively focused on mammalian target of rapamycin inhibitors, which are thought to be the only class of immunosuppressive agents that can reduce HCC recurrence. In fact, substantial evidence from the bench to the bedside indicates that other classes of immunosuppressants may also exert diverse effects; for example, inosine monophosphate dehydrogenase inhibitors potentially have antitumor effects. In this article, we aim to provide a comprehensive overview of the potential effects of different types of immunosuppressants on HCC recurrence and their mechanisms of action from both experimental and clinical perspectives. To ultimately improve the outcomes of HCC patients after transplantation, we propose a concept and approaches for developing personalized immunosuppressive medication to be used either as immunosuppression maintenance or during the prevention/treatment of HCC recurrence.

Incidence and long-term risk of de novo malignancies after liver transplantation with implications for prevention and detection

The goal of this study was the characterization of long-term cancer risks after liver transplantation (LT) with implications for prevention and detection. Site-specific cancer incidence rates and characteristics were compared retrospectively for 2000 LT patients from a single institution (January 1, 1983 to December 31, 2010) and the general German population with standardized incidence ratios (SIRs); the total follow-up at December 31, 2011 was 14,490 person-years. The cancer incidence rates for the LT recipients were almost twice as high as those for the age- and sex-matched general population (SIR = 1.94, 95% CI = 1.63-2.31). Significantly increased SIRs were observed for vulvar carcinoma (SIR = 23.80), posttransplant lymphoproliferative disorder/non-Hodgkin lymphoma (SIR = 10.95), renal cell carcinoma (SIR = 2.65), lung cancer (SIR = 1.85), and colorectal cancer (SIR = 1.41). The mean time between transplantation and diagnosis was 6.8 years. The mean age at the time of diagnosis was significantly lower for the cohort versus the general population with similar malignancies [50 years (both sexes) versus 69 and 68 years (males and females), P ≤ 0.006]. Tumors were diagnosed at more advanced stages, and there was a trend of higher grading, which suggested more aggressive tumor growth. Tumor treatment was performed according to accepted guidelines. Surprisingly, 5-year survival was slightly better in the study cohort versus the general population for renal cell carcinoma, lung cancer, colorectal cancer, and thyroid cancer. Long-term immunosuppression with different protocols did not lead to significantly different SIRs, although patients treated with mycophenolate mofetil had the lowest SIR for de novo cancers (1.65, 95% CI = 1.2-2.4). Alcoholic liver disease (SIR = 2.30) and primary sclerosing cholangitis (SIR = 3.40) as indications for LT were associated with an increased risk of de novo malignancies. In conclusion, risk-adapted cancer surveillance is proposed. Tumor treatment performed according to accepted guidelines appears adequate. Mycophenolate may lead to lower long-term risks for de novo cancers.

Mechanism of action of conventional and targeted anticancer therapies: reinstating immunosurveillance

Conventional chemotherapeutics and targeted antineoplastic agents have been developed based on the simplistic notion that cancer constitutes a cell-autonomous genetic or epigenetic disease. However, it is becoming clear that many of the available anticancer drugs that have collectively saved millions of life-years mediate therapeutic effects by eliciting de novo or reactivating pre-existing tumor-specific immune responses. Here, we discuss the capacity of both conventional and targeted anticancer therapies to enhance the immunogenic properties of malignant cells and to stimulate immune effector cells, either directly or by subverting the immunosuppressive circuitries that preclude antitumor immune responses in cancer patients. Accumulating evidence indicates that the therapeutic efficacy of several antineoplastic agents relies on their capacity to influence the tumor-host interaction, tipping the balance toward the activation of an immune response specific for malignant cells. We surmise that the development of successful anticancer therapies will be improved and accelerated by the immunological characterization of candidate agents.

Liver transplantation in alcoholic liver disease current status and controversies

Alcoholic cirrhosis remains the second most common indication for liver transplantation. A comprehensive medical and psychosocial evaluation is needed when making a decision to place such patients on the transplant list. Most transplant centers worldwide need a minimum of 6 mo of alcohol abstinence for listing these patients. Patients with alcohol dependence are at high risk for relapse to alcohol use after transplantation (recidivism). These patients need to be identified and require alcohol rehabilitation treatment before transplantation. Recidivism to the level of harmful drinking is reported in about 15%-20% cases. Although, recurrent cirrhosis and graft loss from recidivism is rare, occurring in less than 5% of all alcoholic cirrhosis-related transplants, harmful drinking in the post-transplant period does impact the long-term outcome. The development of metabolic syndrome with cardiovascular events and de novo malignancy are important contributors to non liver-related mortality amongst transplants for alcoholic liver disease. Surveillance protocols for earlier detection of de novo malignancy are needed to improve the long-term outcome. The need for a minimum of 6 mo of abstinence before listing makes transplant a nonviable option for patients with severe alcoholic hepatitis who do not respond to corticosteroids. Emerging data from retrospective and prospective studies has challenged the 6 mo rule, and beneficial effects of liver transplantation have been reported in select patients with a first episode of severe alcoholic hepatitis who are unresponsive to steroids.

mTOR signaling in liver regeneration: Rapamycin combined with growth factor treatment

AIM: To investigate the effects of mammalian target of rapamycin (mTOR) inhibition on liver regeneration and autophagy in a surgical resection model.

METHODS: C57BL/6 mice were subjected to a 70% partial hepatectomy (PH) and treated intraperitoneally every 24 h with a combination of the mTOR inhibitor rapamycin (2.5 mg/kg per day) and the steroid dexamethasone (2.0 mg/kg per day) in phosphate buffered saline (PBS) or with PBS alone as vehicle control. In the immunosuppressant group, part of the group was treated subcutaneously 4 h prior to and 24 h after PH with a combination of human recombinant interleukin 6 (IL-6; 500 μg/kg per day) and hepatocyte growth factor (HGF; 100 μg/kg per day) in PBS. Animals were sacrificed 2, 3 or 5 d after PH and liver tissue and blood were collected for further analysis. Immunohistochemical staining for 5-Bromo-2’-deoxyuridine (BrdU) was used to quantify hepatocyte proliferation. Western blotting was used to detect hepatic microtubule-associated protein 1 light chain 3 (LC3)-II protein expression as a marker for autophagy. Hepatic gene expression levels of proliferation-, inflammation- and angiogenesis-related genes were examined by real-time reverse transcription-polymerase chain reaction and serum bilirubin and transaminase levels were analyzed at the clinical chemical core facility of the Erasmus MC-University Medical Center.

RESULTS: mTOR inhibition significantly suppressed regeneration, shown by decreased hepatocyte proliferation (2% vs 12% BrdU positive hepatocyte nuclei at day 2, P < 0.01; 0.8% vs 1.4% at day 5, P = 0.02) and liver weight reconstitution (63% vs 76% of initial total liver weight at day 3, P = 0.04), and furthermore increased serum transaminase levels (aspartate aminotransferase 641 U/L vs 185 U/L at day 2, P = 0.02). Expression of the autophagy marker LC3-II, which was reduced during normal liver regeneration, increased after mTOR inhibition (46% increase at day 2, P = 0.04). Hepatic gene expression showed an increased inflammation-related response [tumor necrosis factor (TNF)-α 3.2-fold upregulation at day 2, P = 0.03; IL-1Ra 6.0-fold upregulation at day 2 and 42.3-fold upregulation at day 5, P < 0.01] and a reduced expression of cell cycle progression and angiogenesis-related factors (HGF 40% reduction at day 2; vascular endothelial growth factor receptor 2 50% reduction at days 2 and 5; angiopoietin 1 60% reduction at day 2, all P≤ 0.01). Treatment with the regeneration stimulating cytokine IL-6 and growth factor HGF could overcome the inhibitory effect on liver weight (75% of initial total liver weight at day 3, P = 0.02 vs immunosuppression alone and P = 0.90 vs controls) and partially reversed gene expression changes caused by rapamycin (TNF-α and IL-1Ra levels at day 2 were restored to control levels). However, no significant changes in hepatocyte proliferation, serum injury markers or autophagy were found.

CONCLUSION: mTOR inhibition severely impairs liver regeneration and increases autophagy after PH. These effects are partly reversed by stimulation of the IL-6 and HGF pathways.

Impact of cyclosporine versus tacrolimus on the incidence of de novo malignancy following liver transplantation: a single center experience with 609 patients

De novo malignancies are a major cause of late death after liver transplantation. Aim of the present study was to determine whether use of cyclosporine versus tacrolimus affects long-term tumor incidence considering potential confounders. De novo malignancies in 609 liver transplant recipients at Munich Transplant Centre between 1985 and 2007 were registered. In 1996, the standard immunosuppressive regimen was changed from cyclosporine to tacrolimus. Different effects of those drugs on long-term tumor incidence were analyzed in multivariate analysis. During 3765 patient years of follow-up (median 4.78 years), 87 de novo malignancies occurred in 71 patients (mean age 47.5 ± 13.3 years, mean time after liver transplantation 5.7 ± 3.7 years). The cumulative incidence of de novo malignancies was 34.7% for all tumor entities after 15 years as compared to 8.9% for a nontransplanted population. The most frequent tumors observed were nonmelanoma skin cancers (44.83%). Moreover, post-transplant lymphoid disease, oropharyngeal cancer (n = 6, 6.9%), upper gastrointestinal tract cancer (n = 4, 4.6%), lung cancer (n = 4, 4.6%), gynecological malignancies (n = 4, 4.6%), and kidney cancer (n = 3, 3.45%) were detected. Multivariate analysis revealed recipient age [hazards ratio (HR) 1.06], male gender (HR 1.73), and tacrolimus-based immunosuppression (HR 2.06) as significant risk factors. Based on those results, a tacrolimus-based immunosuppression should be discussed especially in older male patients. Whether reducing tacrolimus target levels may reduce the risk for de novo malignancies has yet to be determined in prospective trials.

Tumor promotion through the mesenchymal stem cell compartment in human hepatocellular carcinoma

Although the infiltration of mesenchymal stem (stromal) cells (MSCs) into different tumors is widely recognized in animal models, the question whether these MSCs have a positive or negative effect on disease progression remains unanswered. The aim of this study is to investigate whether human hepatocellular carcinoma (HCC) harbors MSCs and whether these MSCs affect tumor growth. We observed that cells capable of differentiation into both adipocyte and osteocyte lineages and expressing MSC markers can be cultured from surgically resected HCC tissues. In situ staining of human HCC tissues with a STRO-1 antibody showed that the tumor and tumor-stromal region are significantly enriched with candidate MSCs compared with adjacent tissue (n = 12, P < 0.01). In mice, coengraftment of a human HCC cell line (Huh7) with MSCs resulted in substantially larger tumors compared with paired engraftment of Huh7 alone (n = 8, P < 0.01). Consistently, coculturing Huh7 with irradiated MSCs significantly increased the number and the size of colonies formed. This enhancement of Huh7 colony formation was also observed by treatment of MSC-conditioned medium (MSC-CM), suggesting that secreted trophic factors contribute to the growth-promoting effects. Genome-wide gene expression array and pathway analysis confirmed the upregulation of cell growth and proliferation-related processes and downregulation of cell death-related pathways by treatment of MSC-CM in Huh7 cells. In conclusion, these results show that MSCs are enriched in human HCC tumor compartment and could exert trophic effects on tumor cells. Thus, targeting of HCC tumor MSCs may represent a new avenue for therapeutic intervention.