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

Current Use of Immunosuppression in Liver Transplantation

Since the first successful liver transplant in 1967, immunosuppression has allowed liver transplantation to become the standard treatment of end-stage liver disease. Over the decades, the rates of rejection have decreased, and patient survival outcomes have significantly improved in large part due to the introduction and advancements of immunosuppression medications. However, the adverse effects associated with long-term immunosuppression have created new challenges facing liver transplantation and added significantly to posttransplantation morbidity. This review presents the data and rationale for immunosuppression approaches, addresses the main controversies related to immunosuppression in liver transplantation, and explores some of the newer advancements in immunosuppressive drug therapy.

Mycosis Fungoides in Solid-Organ Transplant Recipients: A Multicenter Retrospective Cohort Study

BACKGROUND

Mycosis fungoides (MF) in solid-organ transplant recipients (SOTRs) is rare, with limited data on disease characteristics.

OBJECTIVE

The aim was to study the characteristics of MF in SOTRs with an emphasis on the immunosuppressive therapy.

METHODS

A retrospective cohort of patients diagnosed with MF, who were also SOTRs, were followed at 3 cutaneous lymphoma outpatient clinics, between January 2010 and February 2022.

RESULTS

Ten patients were included (7 male; median ages at transplantation and at diagnosis of MF were 33 and 48 years, respectively; 40% were diagnosed before the age of 18 years). Median time from transplantation to diagnosis of MF was 8 years (range 0.5-22). Transplanted organs and immunosuppressive treatments included: liver (n = 5; 4 treated with tacrolimus, 1 with tacrolimus and prednisone), kidney (n = 3), liver and kidney (n = 1), and heart (n = 1), all treated with mycophenolic acid, tacrolimus, and prednisone. Nine had early-stage MF (IA - 4, IB - 5; 40% with early folliculotropic MF), treated with skin-directed therapies, in 2 combined with acitretin, achieving partial/complete response. One patient had advanced-stage MF (IIIA) with folliculotropic erythroderma, treated with ultraviolet A and narrow-band ultraviolet B with acitretin, achieving partial response. Immunosuppression was modified in 3. At last follow-up (median 4 years, range 1-8), no stage progression was observed; 5 had no evidence of disease, 5 had active disease (IA/IB - 4, III - 1).

CONCLUSIONS

MF in SOTRs is usually diagnosed at an early stage, with overrepresentation of folliculotropic MF, and of children. Immunosuppressive therapy alterations, not conducted in most patients, should be balanced against the risk of organ compromise/rejection. Disease course was similar to MF in immunocompetent patients, during the limited time of follow-up.

Early Everolimus-Facilitated Reduced Tacrolimus in Liver Transplantation: Results From the Randomized HEPHAISTOS Trial

Everolimus-facilitated reduced-exposure tacrolimus (EVR + rTAC) at 30 days after liver transplantation (LT) has shown advantages in renal preservation. This study evaluated the effects of early initiation of EVR + rTAC in de novo LT recipients (LTRs). In HEPHAISTOS (NCT01551212, EudraCT 2011-003118-17), a 12-month, multicenter, controlled study, LTRs were randomly assigned at 7 to 21 days after LT to receive EVR + rTAC or standard-exposure tacrolimus (sTAC) with steroids. The primary objective was to demonstrate superior renal function (assessed by estimated glomerular filtration rate [eGFR]) with EVR + rTAC versus sTAC at month 12 in the full analysis set (FAS). Other assessments at month 12 included the evaluation of renal function in compliance set and on-treatment (OT) patients, efficacy (composite endpoint of graft loss, death, or treated biopsy-proven acute rejection [tBPAR] and individual components) in FAS, and safety. In total, 333 patients (EVR + rTAC, 169; sTAC, 164) were included in the FAS. A high proportion of patients was nonadherent in maintaining tacrolimus trough levels (EVR + rTAC, 36.1%; sTAC, 34.7%). At month 12, the adjusted least square mean eGFR was numerically higher with EVR + rTAC versus sTAC (76.2 versus 72.1 mL/minute/1.73 m² , difference: 4.1 mL/minute/1.73 m² ; P = 0.097). A significant difference of 8.3 mL/minute/1.73 m² (P = 0.03) favoring EVR + rTAC was noted in the compliance set. Incidence of composite efficacy endpoint (7.7% versus 7.9%) and tBPAR (7.1% versus 5.5%) at month 12 as well as incidence of treatment-emergent adverse events (AEs) and serious AEs were comparable between groups. A lower proportion of patients discontinued EVR + rTAC than sTAC treatment (27.2% versus 34.1%). Early use of everolimus in combination with rTAC showed comparable efficacy, safety, and well-preserved renal function versus sTAC therapy at month 12. Of note, renal function was significantly enhanced in the compliance set.

Sunitinib-related high-grade proteinuria and allograft dysfunction in a kidney recipient: a rare case report

Background

Sunitinib-induced high-grade proteinuria and irreversible renal allograft dysfunction are rare conditions. Here, we present a patient who had received renal allograft and later developed metastatic clear cell renal cell carcinoma(cc-mRCC), for which he was prescribed sunitinib. High-grade proteinuria, hypoalbuminemia, peripheral edema and renal allograft dysfunction (manifesting as an increase in the serum creatinine concentration) occurred 5 months after sunitinib prescription.

Case presentation

The patient was a 58-year-old male who had end-stage renal disease with regular hemodialysis through arteriovenous fistula for 17 years since 1998 and received a renal allograft from a deceased kidney donor in 2015. Unfortunately, in 2019, the patient developed cc-mRCC originating from the left native kidney. We suggested a needle biopsy on left native kidney or radical left nephrectomy, but the patient refused. Sunitinib was prescribed. Follow-up urine analysis showed proteinuria (500 mg/dL) 2 weeks after sunitinib prescription. He was hospitalized 5 months later because of body weight gain, decreased urine output, pitting edema of both lower extremities, and shortness of breath. The image studies showed progression in his cc-mRCC. His serum creatinine level and spot urine protein at admission increased to 4.26 mg/dL and 300 mg/dL, respectively. He agreed on a biopsy for the renal allograft and the pathology studies showed focal segmental glomerulosclerosis, acute interstitial nephritis, and acute tubular injury. Based on the time sequence of clinical presentations with the laboratory and pathological findings, sunitinib-induced renal allograft dysfunction secondary to high-grade proteinuria was most likely. Despite of discontinuation of sunitinib and increased dose of everolimus, renal impairment progressed. Thus, he had to receive hemodialysis starting 2 week after hospitalization. Unfortunately, the patient died of advanced metastasis despite of aggressive medical treatments 3 weeks after admission.

Conclusion

This case report is a reminder that renal allograft dysfunction can happen secondary to proteinuria after taking sunitinib. Hence, clinicians must regularly check renal function and urine protein for renal allograft recipients. Monitoring and modifying drug prescription, especially sunitinib, is necessary if persistent proteinuria accompanied by deteriorating serum creatinine level occurs. Renal biopsy may be considered if more evidence is required to make a differential diagnosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-022-02789-5.

Sirolimus in renal transplant recipients with malignancies in Germany

Background

Renal transplant recipients have an increased cancer risk. The mammalian target of rapamycin inhibitor sirolimus (SRL) has immunosuppressive and antitumour activities but knowledge about its use in recipients with cancer is limited.

Methods

We retrospectively analysed 726 renal allograft recipients converted to SRL from 10 German transplant centres. Patient and graft survival were analysed depending on malignancy status prior to conversion and tumour entity.

Results

Malignancy before conversion to SRL was reported in 230 patients, with 137 patients having skin cancers and 101 having solid cancers. Cancer occurred 4.6 ± 9.4 (median 3.0) years after transplantation. Basal cell carcinoma, squamous cell carcinoma and Bowen’s disease were the most prevalent skin cancers, while carcinomas of the kidney, colon and breast were the most prevalent solid cancers before conversion. Patients with prior malignancy were older and had better renal function at conversion compared with patients without a history of cancer. After conversion to SRL, cancer incidence rates (IRs) of all tumours were lower compared with rates before conversion. Cancer IRs after conversion were higher in patients with malignancy before conversion compared with those without. Patient survival was worse in patients with solid cancers compared with patients with skin cancers or without malignancies. Biopsy-proven acute rejections in the first year after conversion were less frequent in patients with malignancy compared with those without. Graft survival and renal function in all cancer types were better than in patients converted to SRL without cancers.

Conclusions

Conversion to SRL in patients with a history of cancer is safe regarding renal function and graft survival, while patient survival is largely dependent on tumour entity.

Long-term outcome of kidney transplant by using restored kidney grafts after tumour ex vivo excision - a prospective study

The aim of this study is to report long-term outcomes of kidney transplantation by using the kidney graft after a small tumour ex vivo excision. A structured programme was established to use the restored kidney graft from urological referral after radical nephrectomy. The criteria were defined as tumour size ≤3 cm, margin clear on frozen section and recipients aged ≥60 years or those on the urgent list for transplantation as a result of imminent lack of dialysis access. The recipients were followed up regularly for surveillance of tumour recurrence. Between February 2007 and February 2018, 28 recipients had kidney transplantation by using the restored kidney grafts. The tumour size was 2.6 ± 0.7 cm. The follow-up was median 7 years without evidence of tumour recurrence. The patient and graft survival was satisfactory. Kidney transplantation by using restored kidneys after a small tumour excision is a novel source for selected recipients. The long-term patient and graft survival is satisfactory. Although there is a risk of tumour recurrence, it is rare event. Together with literature review, we would support use of kidney graft after a small tumour excision for selected recipients.

Programmed T cell differentiation: Implications for transplantation

While T cells play a critical role in protective immunity against infection, they are also responsible for graft rejection in the setting of transplantation. T cell differentiation is regulated by both intrinsic transcriptional pathways as well as extrinsic factors such as antigen encounter and the cytokine milieu. Herein, we review recent discoveries in the transcriptional regulation of T cell differentiation and their impact on the field of transplantation. Recent studies uncovering context-dependent differentiation programs that differ in the setting of infection or transplantation will also be discussed. Understanding the key transcriptional pathways that underlie T cell responses in transplantation has important clinical implications, including development of novel therapeutic agents to mitigate graft rejection.

The change of immunosuppressive regimen from calcineurin inhibitors to mammalian target of rapamycin (mTOR) inhibitors and its effect on malignancy following heart transplantation

Malignancy is a significant cause of mortality after organ transplantation. There is an increased rate of malignancy following heart transplantation (HTx) compared to the general population and other organ transplant recipients. Post-HTx patients with a history of malignancy are also at a higher risk of developing new malignancies or exacerbation of their existing malignancies. Mammalian target of Rapamycin inhibitors (mTORIs) are newly introduced immunosuppressive drugs with a unique mechanism of action. By changing the immunosuppressive regimen from classic drugs, especially calcineurin inhibitors (CNIs) to mTORIs, the rate of developing de novo malignancies and the relapse of former malignancies is significantly reduced. However, issues like allograft function, total surveillance of patients, and post-transplantation complications should be considered during the conversion of drug regimens utilizing CNIs to drug regimens employing mTORIs. We reviewed different post-heart transplant maintenance immunosuppressive regimens and their effect on post-HTx malignancies with a focus on mTORIs, compared safety against effectiveness, and gathered conclusions based on our review of the literature, which may lead clinicians to make a better evidence-based decision regarding post-HTx maintenance immunosuppressive drug regimens. Overall, CNI to mTORI conversion in post-HTx maintenance immunosuppressive drug regimens was associated with a reduced rate of developing malignancy in post-HTx patients. Furthermore, nephrotoxicity decreased significantly while using mTORIs in combination with lower doses of CNIs and the rejection rate was equivalent to CNI-only regimens. In conclusion, mTORI-based maintenance immunosuppressive drug regimens seem to be safe and beneficial when considering efficacy vs. adverse effects, and all-cause mortality rates are significantly lower in patients switched to mTORIs when compared to CNI recipients.

International Liver Transplantation Society Consensus Statement on Immunosuppression in Liver Transplant Recipients

Effective immunosupression management is central to achieving optimal outcomes in liver transplant recipients. Current immunosuppression regimens and agents are highly effective in minimizing graft loss due to acute and chronic rejection but can also produce a substantial array of toxicities. The utilization of immunosuppression varies widely, contributing to the wide disparities in posttransplant outcomes reported between transplant centers. The International Liver Transplantation Society (ILTS) convened a consensus conference, comprised of a global panel of expert hepatologists, transplant surgeons, nephrologists, and pharmacologists to review the literature and experience pertaining to immunosuppression management to develop guidelines on key aspects of immunosuppression. The consensus findings and recommendations of the ILTS Consensus guidelines on immunosuppression in liver transplant recipients are presented in this article.

mTOR Inhibition and Clinical Transplantation: Liver

The evidence base concerning use of mammalian target of rapamycin (mTOR) inhibitor therapy after liver transplantation is evolving rapidly, clarifying their benefits and disadvantages in different clinical scenarios. The H2304 trial showed that starting everolimus at 1 month posttransplant, with reduced tacrolimus, achieves a sustained improvement in renal function versus standard tacrolimus-based therapy, with at least equivalent immunosuppressive efficacy. Randomized studies evaluating early discontinuation of calcineurin inhibitor (CNI) therapy after introduction of an mTOR inhibitor consistently demonstrated a substantial improvement in renal function versus standard CNI therapy. However, concomitant mycophenolic acid is advisable to avoid an increase in mild biopsy-proven acute rejection, and induction with an interleukin-2 receptor antagonist may also be helpful. High-quality robust data regarding prevention of posttransplant malignancies under mTOR inhibitors is lacking in liver transplantation, although there are some indications of benefit. In maintenance patients, robust data are limited regarding mTOR inhibitor initiation in response to deteriorating renal function or other indications but late conversion (>1 year) appears ineffective. Rates of mTOR inhibitor discontinuation due to adverse events are high, affecting at least a quarter of patients. In conclusion, the evidence base for use of mTOR inhibitors early posttransplant to support CNI reduction now convincingly demonstrates a renal advantage, but adequate adjunctive immunosuppression is essential to preserve efficacy.

Donor-derived Kaposi's sarcoma in a liver-kidney transplant recipient

Human herpes virus 8 (HHV-8), also known as Kaposi's sarcoma associated herpesvirus (KSHV), is an oncogenic virus that can cause Kaposi's sarcoma (KS). KS can develop following organ transplantation through reactivation of the recipient's latent HHV-8 infection, or less commonly through donor-derived infection which has higher risk for severe illness and mortality. We describe a case of probable donor-derived KS in the recipient of a liver-kidney transplant. The donor had multiple risk factors for HHV-8 infection. The KS was successfully treated by switching immunosuppression from tacrolimus to sirolimus. With an increasing number of human immunodeficiency virus (HIV)-positive persons seeking organ transplantation and serving as organ donors for HIV-positive recipients, HHV-8 prevalence among donors and recipients will likely increase and with that the risk for post-transplant KS. Predetermination of HHV-8 status can be useful when considering organ donors and recipients with risk factors, although there are currently no validated commercial tests for HHV-8 antibody screening.

Risk Factors for Melanoma in Renal Transplant Recipients

Importance

Melanoma risk factors and incidence in renal transplant recipients can inform decision making for both patients and clinicians.

Objective

To determine risk factors and characteristics of renal transplant recipients who develop melanoma.

Design, Setting, and Participants

This cohort study of a large national data registry used a cohort of renal transplant recipients from the United States Renal Data System (USRDS) database from the years 2004 through 2012. Differences in baseline characteristics between those who did and did not develop melanoma were examined, and a survival analysis was performed. Patients with renal transplants who received a diagnosis of melanoma according to any inpatient or outpatient claim associated with a billing code for melanoma were included. A history of pretransplant melanoma, previous kidney transplantation, or transplantation after 2012 or before 2004 were exclusion criteria. The data analysis was conducted from 2015 to 2016.

Exposure

Receipt of a renal transplant.

Main Outcomes and Measures

Incidence and risk factors for melanoma.

Results

Of 105 174 patients (64 151 [60.7%] male; mean [SD] age, 49.6 [15.3] years) who received kidney transplants between 2004 and 2012, 488 (0.4%) had a record of melanoma after transplantation. Significant risk factors for developing melanoma vs not developing melanoma included older age among recipients (mean [SD] age, 60.5 [10.2] vs 49.7 [15.3] years; P < .001) and donors (42.6 [15.0] vs 39.2 [15.1] years; P < .001), male sex (71.5% vs 60.7%; P < .001), recipient (96.1% vs 66.5%; P < .001) and donor (92.4% vs 82.9%; P < .001) white race, less than 4 HLA mismatches (44.9% vs 37.1%; P = .001), living donors (44.7% vs 33.7%; P < .001), and sirolimus (22.3% vs 13.2%; P < .001) and cyclosporine (4.9% vs 3.2%; P = .04) therapy. Risk factors significant on survival analysis included older recipient age (hazard ratio [HR] per year, 1.06; 95% CI, 1.05-1.06; P < .001), recipient male sex (HR, 1.53; 95% CI, 1.25-1.88; P < .001), recipient white race, living donors (HR, 1.35; 95% CI, 1.11-1.64; P = .002), and sirolimus (HR, 1.54; 95% CI, 1.22-1.94; P < .001) and cyclosporine (HR, 1.93; 95% CI, 1.24-2.99; P = .004) therapy. The age-standardized relative rate of melanoma in USRDS patients compared with Surveillance, Epidemiology, and End Results patients across all years was 4.9. A Kaplan-Meier estimate of the median time to melanoma among those patients who did develop melanoma was 1.45 years (95% CI, 1.31-1.70 years).

Conclusions and Relevance

Renal transplant recipients had greater risk of developing melanoma than the general population. We believe that the risk factors we identified can guide clinicians in providing adequate care for patients in this vulnerable group.

Survival Benefit of Early Cancer Detection Through Regular Endoscopic Screening for De Novo Gastric and Colorectal Cancers in Korean Liver Transplant Recipients

BACKGROUND

De novo malignancy is not uncommon after liver transplantation (LT). Gastric cancer is one of the most common malignancies in both the Korean general population and LT recipients, and colorectal cancer prevalence is gradually increasing.

METHODS

Among 3690 adult recipients who underwent LT from January 1999 and December 2013, the screening patterns and prognosis of 26 cases of gastric cancer and 22 cases of colorectal cancer were analyzed.

RESULTS

For gastric cancer, the mean patient age was 54.6 ± 6.2 years at LT and 59.5 ± 6.7 years at cancer diagnosis, with a post-transplant interval of 60.2 ± 29.8 months. Patients were divided into regular (n = 18) and non-regular (n = 8) screening groups, with early cancer found in 14 and 0 patients; their 2-year survival rates after cancer diagnosis were 93.1% and 33.3% (P = .006), respectively. Endoscopic resection was successfully performed in 8 patients, all in the regular screening group. For colorectal cancer, the mean patient age was 53.3 ± 6.1 years at LT and 58.1 ± 6.7 years at cancer diagnosis, with a post-transplant interval of 54.3 ± 38.0 months. Patients were divided into regular (n = 19) and non-regular (n = 3) screening groups, with early cancer found in 12 and 0 patients; their 2-year survival rates after cancer diagnosis of 92.3% and 33.3% (P = .003), respectively. Endoscopic resection was successfully performed in 6 patients, all in the regular screening group.

CONCLUSIONS

LT recipients are strongly advised to undergo regular screening studies for various de novo malignancies, especially cancers common in the general population. Regular endoscopic screening contributes to the timely detection of gastric and colorectal cancers, improving post-treatment survival outcomes.

Everolimus and Malignancy after Solid Organ Transplantation: A Clinical Update

Malignancy after solid organ transplantation remains a major cause of posttransplant mortality. The mammalian target of rapamycin (mTOR) inhibitor class of immunosuppressants exerts various antioncogenic effects, and the mTOR inhibitor everolimus is licensed for the treatment of several solid cancers. In kidney transplantation, evidence from registry studies indicates a lower rate of de novo malignancy under mTOR inhibition, with some potentially supportive data from randomized trials of everolimus. Case reports and small single-center series have suggested that switch to everolimus may be beneficial following diagnosis of posttransplant malignancy, particularly for Kaposi's sarcoma and nonmelanoma skin cancer, but prospective studies are lacking. A systematic review has shown mTOR inhibition to be associated with a significantly lower rate of hepatocellular carcinoma (HCC) recurrence versus standard calcineurin inhibitor therapy. One meta-analysis has concluded that patients with nontransplant HCC experience a low but significant survival benefit under everolimus monotherapy, so far unconfirmed in a transplant population. Data are limited in heart transplantation, although observational data and case reports have indicated that introduction of everolimus is helpful in reducing the recurrence of skin cancers. Overall, it can be concluded that, in certain settings, everolimus appears a promising option to lessen the toll of posttransplant malignancy.

Posttransplant solid organ malignancies in lung transplant recipients: a single-center experience and review of the literature

PURPOSE

Solid-organ tumor incidences are higher in solid organ transplant patients than in the general population. The aim of this study was to analyze solid-organ tumor frequency and characteristics in a population of lung transplant patients and provide a brief review of the literature.

METHODS

A retrospective analysis was conducted of all patients who underwent a lung transplant in the Lung Transplant Program at the University Hospital of Siena, Italy, from 2001 to 2014 (n = 119). Patients' demographics, pretransplant characteristics, immunosuppressive therapy, and infectious factors were recorded.

RESULTS

Nine patients with a median age of 59.0 years (range 50-63) of our cohort developed a solid-organ tumor (7.5%). Most of the patients experienced nonmelanoma skin cancer (44.4%); the others were diagnosed with lung cancer (22.2%), breast cancer (22.2%), and colon-rectal cancer (11.2%). The median time from transplantation to tumor diagnosis was 895.0 days (range 321-2046). No differences in pretransplant characteristics, immunosuppressive therapy, or infectious factors were found between patients who developed solid organ tumors and those who did not.

CONCLUSIONS

The present study confirmed that de novo malignancies are a major issue in lung transplant patients; in particular, skin and lung cancers demonstrated a higher incidence rate. Oncologic treatment of these patients is complex, requiring close collaboration between the transplant team and oncologist. Strict screening programs are key factors for an early diagnosis and to allow for prompt treatment resulting in a better outcome.

Association between HLA-A1 and -A2 types and Epstein-Barr virus status of post-transplant lymphoproliferative disorder

The susceptibility to Epstein-Barr virus (EBV)-related post-transplant lymphoproliferative disorder (PTLD) may be affected by the human leukocyte antigen (HLA) type. We investigated HLA-A and HLA-B allele frequencies, focusing on HLA-A1 and -A2, in a population-based case series of EBV + (n = 60) and EBV- (n = 44) PTLD after solid organ transplantation. The proportion of EBV + PTLD was highest in HLA-A1 homozygotes (100%), lower in carriers of HLA-A1/AX (79%), HLA-A1/A2 (55%), HLA-A2/AX (54%), and lowest in HLA-A2 homozygotes (37%). HLA-A1 type was overrepresented (22% versus 7%, p = 0.05) and HLA-A2 type underrepresented (57% versus 80%, p = 0.01) in patients with EBV + compared with EBV - PTLD. EBV + PTLD in HLA-A1 carriers developed almost exclusively in already EBV-seropositive individuals. EBV status of PTLD was not related to any other HLA-A or HLA-B type. Our findings suggest that HLA-A1 carriers may have an increased risk of EBV + PTLD due to a decreased ability to control the latent EBV infection.

Cancer immunotherapy via nucleic acid aptamers

Over the past decade, immune therapy has become a standard treatment for a variety of cancers. Monoclonal antibodies, immune adjuvants and vaccines against oncogenic viruses are now well-established cancer therapies. Immune modulation is a principal element of supportive care for many high-dose chemotherapy regimens. Aptamers are short nucleic acids that bind to defined targets with high affinity and specificity. The first aptamers have been selected around two decades ago by an in vitro process named SELEX (systematic evolution of ligands by exponential enrichment). Since then, numerous aptamers with specificities for a variety of targets from small molecules to proteins or even whole cells have been selected. Targeting immunomodulatory ligands in the progressive tumor lesions of the patients would be prophylactic or therapeutic and may reduce drug-associated toxicities. A new class of inhibitory and agonistic ligands composed of short oligonucleotide (ODN) aptamers was developed recently that exhibited bioactivities comparable or superior to that of antibodies. This paper addressed progress in cancer immunotherapy with nucleic acid aptamers and highlighted recent developments either in immune system targeting or in immunotherapy methods involved aptamers. We discussed aptamer limitations when used as therapeutic agents for cancer treatment and suggested ways to overcome those limitations.

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.

Multiple indications for everolimus after liver transplantation in current clinical practice

AIM: To assess our experience with the use and management of everolimus-based regimens post-liver transplantation and to redefine the potential role of this drug in current clinical practice.

METHODS: From October 1988 to December 2012, 1023 liver transplantations were performed in 955 patients in our Unit. Seventy-four patients (7.74%) received immunosuppression with everolimus at some time post-transplantation. Demographic characteristics, everolimus indication, time elapsed from transplantation to the introduction of everolimus, doses and levels administered, efficacy, side effects, discontinuation and post-conversion survival were analyzed.

RESULTS: Mean age at the time of conversion to everolimus was 57.7 ± 10 years. Indications for conversion were: refractory rejection 31.1%, extended hepatocellular carcinoma in explanted liver 19%, post-transplant hepatocellular carcinoma recurrence 8.1%, de novo tumour 17.6%, renal insufficiency 8.1%, severe neurotoxicity 10.8%, and others 5.4%. Median time from transplantation to introduction of everolimus was 6 mo (range: 0.10-192). Mean follow-up post-conversion was 22 ± 19 mo (range: 0.50-74). The event for which the drug was indicated was resolved in 60.8% of patients, with the best results in cases of refractory rejection, renal insufficiency and neurotoxicity. Results in patients with cancer were similar to those of a historical cohort treated with other immunosuppressants. The main side effects were dyslipidemia and infections. Post-conversion acute rejection occurred in 14.9% of cases. The drug was discontinued in 28.4% of patients.

CONCLUSION: Everolimus at low doses in combination with tacrolimus is a safe immunosuppressant with multiple early and late indications post-liver transplantation.