Malignancies after heart transplantation: incidence, risk factors, and effects of calcineurin inhibitor withdrawal

Incidence of de novo malignancy and all-cause mortality among heart transplant recipients

BACKGROUND

Heart transplant recipients develop cancer at two-times the rate compared to the general population. However, the incidence and mortality rates and the adjusted association between cancer and mortality remains unclear.

METHODS

We estimated the incidence and mortality rates and the adjusted association between developing cancer (any, skin, hematologic, and solid tumor subtypes) and the all-cause mortality rates among adult heart transplant recipients from the Scientific Registry of Transplant Recipients from October 1, 1987, until June 28, 2020.

RESULTS

Among 51,597 adult heart transplant recipients, 13,191 (25.6%) were diagnosed with de novo malignancy throughout the follow-up period. The cumulative incidence cancer at years 1, 5, 10, and 20 was 3%, 16.4%, 32.8%, and 56.6%, respectively. Among those with cancer, the cumulative mortality was 17.5%, 42.3%, 65%, and 91% at years 1, 5, 10, and 20, respectively. The incidence rate of any de novo malignancy was 38.7 cases per 1000 person-years and the mortality rate (for those with cancer) was 115.2 cases per 1000 person-years. Compared to those without cancer, those with cancer had a higher adjusted mortality association [HR: 2.14 (2.07, 2.21)]. The strongest associations were estimated for pancreatic [10.63 (8.34, 13.54)], leukemia [8.06 (4.33, 15.00)], and esophagus [6.94 (5.43, 8.87)] malignancies. The association between de novo malignancies and mortality was higher in the earlier years of follow-up.

CONCLUSION

Compared to not developing cancer, those with de novo malignancy have a 2-fold higher mortality rate, on average. The strength of the association varies by cancer subtype and by follow-up time.

Quality of Life in Patients 20-31 Years After Heart Transplantation

BACKGROUND

Survival rates after heart transplantation (HTx) have significantly improved over the last decades. There is a growing need to understand the long-term psychological and somatic outcomes, which constitute quality of life (QoL), for these long-term survivors.

METHODS

The QoL of patients (N = 75) living 20-31 years (M = 24.9 years, SD = 2.3 years) after orthotopic HTx was evaluated. In a first step, a detailed overview of the patients' somatic condition was assessed. Secondly, patients were compared to 58 control subjects in terms of self-reported QoL (SF-36) and psychological domains (GBB-24; HADS). Finally, a cluster analysis was conducted to identify patterns within the patient-reported outcome measures (PROMs) and to relate them to somatic, psychosocial, and demographic variables.

RESULTS

95.7% of the HTx-patients were in NYHA functional class I or II, and only 15.2% had a reduced LVEF. Compared to controls, long-term HTx patients had significantly lower scores on the physical component summary (PCS) of QoL and on the GBB-24 but not in the mental component summary (MCS) of QoL, or anxiety and depression (HADS). Clustering revealed two distinct groups of patients characterized by high versus low functioning and different levels of social support.

CONCLUSIONS

Long-term survivors have a good functional, cardiac, and mental status, but report a lower physical QoL and higher levels of subjective complaints. The importance of social support for HTx recipients is once again highlighted.

New insights into the oncological risk in heart transplant recipients: could skin tumors represent a marker of increased risk for solid neoplasm?

BACKGROUND

Solid organ transplant recipients are at increased risk for skin cancers due to immune-suppressive therapies. However, little is known about the risk and the characteristics of neoplasms in heart transplant recipients (HTRs). The aim of this study is to delineate the incidence of different skin tumors in HTRs and to correlate it with the incidence of other malignancies, including solid tumors and hematological neoplasms.

METHODS

Patients who underwent to HTRs between January 1991 and November 2021 were retrieved. Clinical data on immunosuppressive therapies, skin tumors, solid and hematological neoplasms were obtained. HTRs with skin tumors were included in group A, while patients with no evidence of skin tumors during the follow-up were included in group B.

RESULTS

One hundred and eight patients were retrieved. A significant increase in solid tumors was observed in group A, while no significant difference in hematological neoplasms was detected between the two groups.

CONCLUSIONS

HTRs with skin tumors showed a significantly higher incidence of solid neoplasms. In most of the cases the skin tumor preceded the onset of the solid neoplasm, suggesting that the skin tumor could represent a 'marker' of immunosuppression eventually leading to the development of an internal malignancy.

Evaluation of 18-FDG PET diagnostic capabilities for cancer screening in heart transplant patients, a retrospective study

Evaluate 18-FDG positron emission tomography (PET) diagnostic capabilities for cancer screening in heart transplant patients. We conducted an anonymized retrospective observational study of heart transplant patients followed in the University Hospital of Montpellier, France. We analyzed 303 18-FDG PET from 158 patients. We compared demographic and clinical characteristics through uni- and multivariate analysis: in the cancer-free group, comparisons were made between the PET false positive (FP) group versus true negative (TN), and in the cancer group, comparisons were made between the PET false negative (FN) group versus true positive (TP). Out of the 303 exams, we found 245 TN, 26 TP, 26 FP and 6 FN. The sensitivity rate was calculated at 81%, the specificity rate at 90%, the positive predictive value at 50%, and the negative predictive value at 97%. The multivariate analysis showed an association between FP diagnosis and graft-PET delay (P value = .046, OR = 5.14, 95% CI [1.18-32.4]) and creatine reactive protein (CRP) ≥ 10 mg/L (P value = .042, OR = 4.21, 95% CI [1.02-17.2]). The estimated probability of FP by logit regression was 0.48 with 95% CI [0.21-0.77] when graft-PET delay ≥ 6 years and CRP ≥ 10 mg/L. No significative statistical link was found for the demographic or clinical characteristics in the FN group of patients with cancer, except for sex (all FN were men). 18-FDG PET performed very well in the follow-up of heart transplant patients for neoplasia screening, with better specificity than sensitivity. However, the study showed that almost 50% of FP can be predicted by considering only the graft-PET delay and CRP.

Sex differences in clinical characteristics and outcomes in patients undergoing heart transplantation

AIMS

Whether sex affects selection for and outcomes after heart transplantation (HTx) remains unclear. We aimed to show sex differences in pre-transplant characteristics and outcomes after HTx.

METHODS AND RESULTS

From 1995 to 2019, 49 200 HTx recipients were prospectively enrolled in the Organ Procurement and Transplantation Network. Logistic regression models were used to evaluate clinical characteristics by sex. Multivariable Cox regression models were fitted to assess sex differences in all-cause mortality, cardiovascular mortality, graft failure, cardiac allograft vasculopathy (CAV), and malignancy. In 49 200 patients (median age 55 years, interquartile range 46-62; 24.6% women), 49 732 events occurred during a median follow-up of 8.1 years. Men were older than women, had more often ischaemic cardiomyopathy (odds ratio [OR] 3.26, 95% confidence interval [CI] 3.11-3.42; P < 0.001), and a higher burden of cardiovascular risk factors, whereas women had less malignancies (OR 0.47, CI 0.44-0.51; P < 0.001). Men were more often treated in intensive care unit (OR 1.24, CI 1.12-1.37; P < 0.001) with a higher need for ventilatory (OR 1.24, CI 1.17-1.32; P < 0.001) or VAD (OR 1.53, CI 1.45-1.63; P < 0.001) support. After multivariable adjustment, men had a higher risk for CAV (hazard ratio [HR] 1.21, CI 1.13-1.29; P < 0.001) and malignancy (HR 1.80, CI 1.62-2.00; P < 0.001). There were no differences in all-cause mortality, cardiovascular mortality, and graft failure between sexes.

CONCLUSIONS

In this US transplant registry, men and women differed in pre-transplant characteristics. Male sex was independently associated with incident CAV and malignancy even after multivariable adjustment. Our results underline the need for better personalized post-HTx management and care.

Post-transplant Lymphoproliferative Disorder Following Cardiac Transplantation

Post-transplant lymphoproliferative disorder (PTLD) is a spectrum of lymphoid conditions frequently associated with the Epstein Barr Virus (EBV) and the use of potent immunosuppressive drugs after solid organ transplantation. PTLD remains a major cause of long-term morbidity and mortality following heart transplantation (HT). Epstein-Barr virus (EBV) is a key pathogenic driver in many PTLD cases. In the majority of PTLD cases, the proliferating immune cell is the B-cell, and the impaired T-cell immune surveillance against infected B cells in immunosuppressed transplant patients plays a key role in the pathogenesis of EBV-positive PTLD. Preventive screening strategies have been attempted for PTLD including limiting patient exposure to aggressive immunosuppressive regimens by tailoring or minimizing immunosuppression while preserving graft function, anti-viral prophylaxis, routine EBV monitoring, and avoidance of EBV seromismatch. Our group has also demonstrated that conversion from calcineurin inhibitor to the mammalian target of rapamycin (mTOR) inhibitor, sirolimus, as a primary immunosuppression was associated with a decreased risk of PTLD following HT. The main therapeutic measures consist of immunosuppression reduction, treatment with rituximab and use of immunochemotherapy regimens. The purpose of this article is to review the potential mechanisms underlying PTLD pathogenesis, discuss recent advances, and review potential therapeutic targets to decrease the burden of PTLD after HT.

EYE DISEASE IN KIDNEY TRANSPLANTATION: CLINICAL CHALLENGES IN A UNIQUE PATIENT POPULATION

Eye disease is common among kidney transplant recipients and their management is challenging. Chronic kidney disease is associated with ocular complications, both independently and in the context of various systemic disorders. In addition, chronic immunosuppression predisposes kidney transplant recipients to an array of long-term ocular issues. This may be broadly categorized into infections, malignancies, and other immunosuppression-specific side effects. The interdependence of kidney disease, transplant pharmacotherapy and ocular health therefore requires a multispecialty approach. Although the kidney transplant population has grown along with the burden of associated oculopathies, systematic guidelines targeting this patient group are lacking. This evidenced-based narrative review summarizes the pertinent issues that may present in the ophthalmic and optometric clinical settings, with emphasis on collaborative management and directions for future research.

Risk Factors, Treatment and Prognosis of Patients with Lung Cancer after Heart Transplantation

Long-term survival after heart transplantation (HTX) is impacted by adverse effects of immunosuppressive pharmacotherapy, and post-transplant lung cancer is a common occurrence. This study aimed to examine the risk factors, treatment, and prognosis of patients with post-transplant lung cancer. We included 625 adult patients who received HTX at Heidelberg Heart Center between 1989 and 2018. Patients were stratified by diagnosis and staging of lung cancer after HTX. Analysis comprised donor and recipient characteristics, medications including immunosuppressive drugs, and survival after diagnosis of lung cancer. A total of 41 patients (6.6%) were diagnosed with lung cancer after HTX, 13 patients received curative care and 28 patients had palliative care. Mean time from HTX until diagnosis of lung cancer was 8.6 ± 4.0 years and 1.8 ± 2.7 years from diagnosis of lung cancer until last follow-up. Twenty-four patients (58.5%) were switched to an mTOR-inhibitor after diagnosis of lung cancer. Multivariate analysis showed recipient age (HR: 1.05; CI: 1.01-1.10; p = 0.02), COPD (HR: 3.72; CI: 1.88-7.37; p < 0.01), and history of smoking (HR: 20.39; CI: 2.73-152.13; p < 0.01) as risk factors for post-transplant lung cancer. Patients in stages I and II had a significantly better 1-year (100.0% versus 3.6%), 2-year (69.2% versus 0.0%), and 5-year survival (53.8% versus 0.0%) than patients in stages III and IV (p < 0.01). Given the poor prognosis of late-stage post-transplant lung cancer, routine reassessment of current smoking status, providing smoking cessation support, and intensified lung cancer screening in high-risk HTX recipients are advisable.

Malignancy among adult heart transplant recipients following patient-tailored dosing of anti-thymocyte globulin: a retrospective, nested case-control study of individualized dosing

Post-transplant malignancy is diagnosed in approximately 18% of heart transplant patients and is a leading cause of death post-transplant. One modifiable risk factor is the type and amount of immunosuppression received. Contemporary rabbit anti-thymocyte globulin (rATG) dosing strategy using T-cell-guided dosing, and its effect on malignancy in heart transplant patients is unclear. This was a single-center, retrospective chart review of heart transplant recipients receiving rATG for induction. Patients diagnosed with malignancy post-transplant were matched 1:2 to controls using a nested case-control design. The primary endpoint was to determine the relative risk of rATG exposure with the actual incidence of malignancy post-transplant. The secondary endpoint was the impact of maintenance immunosuppression on malignancy risk. Of the 126 patients included in the study, 25 developed malignancy and were matched to 50 control patients. The median cumulative rATG dose in milligrams (mg) between groups was 365 mg in malignancy cases and 480 mg in controls (OR 0.90, 95% CI 0.75-1.08, P = 0.28). In both the univariate and multivariable analysis, there was no statistically significant difference in malignancy risk found with any maintenance immunosuppressant. The results of this study showed that patient-tailored rATG dosing strategies may not be associated with malignancy development as previously thought.

Solid organ transplantation worsens the prognosis of patients with cutaneous squamous cell carcinoma of the head and neck region-Comparison between solid organ transplant recipients and immunocompetent patients

BACKGROUND

Cutaneous squamous cell carcinoma of the head and neck (CSCC-HN) appears to behave more aggressively in immunosuppressed patients. We aimed to investigate this hypothesis by comparing solid organ transplant recipients (SOTR) with CSCC-HN to immunocompetent patients.

METHODS

A retrospective comparative study was conducted for SOTR and immunocompetent patients who were treated for CSCC-HN.

RESULTS

A total of 177 SOTR and 157 immunocompetent patients with CSCC-HN were included. Lymph node metastases were more common in the SOTR group (9% vs 3%), and distant metastases occurred only in SOTR (3% of patients). SOTR had a higher rate of recurrences (19% vs 10%), which were mostly regional (7%) and distant (3%). The 2-year disease-specific survival of SOTR was lower (93% vs 100%).

CONCLUSIONS

SOTR with CSCC-HN has significantly worse outcomes compared to immunocompetent patients. Solid-organ transplantation should be regarded as a negative prognostic factor in patients with CSCC-HN.

Association between infectious event and de novo malignancy after heart transplantation

The aim of the study was to investigate the incidence of and risk factors for de novo malignancy after heart transplantation (HTx) in a single center. We assessed 102 consecutive patients who received HTx and were followed-up in our center regularly for > 1 year from June 2006 to May 2018. We investigated the incidence of and risk factors for de novo malignancy. The cumulative incidence of each malignancy type during the follow-up period was one (0.98%) for skin cancer, four (3.92%) for nonskin solid organ cancer, and six (5.88%) for posttransplant lymphoproliferative disorder (PTLD). The percentage of patients with more than one infectious event ≤ 1 year after HTx was higher in the malignancy group than in the non-malignancy group. Furthermore, Kaplan-Meier analysis revealed that the incidence rate of infectious events was higher in patients with malignancies than in those without (log-rank P < 0.001). After dividing malignancies into a PTLD group and a solid organ malignancy group, we found that negative Epstein-Barr virus serostatus, cytomegalovirus-positive antigenemia, and the occurrence of any viral or gastrointestinal infectious event at ≤ 1 year were more frequent in patients with PTLD than in patients without it. The survival rate was significantly lower for patients with solid organ malignancy than for patients without malignancy. In conclusion, there was a correlation between infectious events and de novo malignancy, particularly in patients with PTLD. We should confirm this finding by conducting a larger cohort study.

Canadian Cardiovascular Society/Canadian Cardiac Transplant Network Position Statement on Heart Transplantation: Patient Eligibility, Selection, and Post-Transplantation Care

Significant practice-changing developments have occurred in the care of heart transplantation candidates and recipients over the past decade. This Canadian Cardiovascular Society/Canadian Cardiac Transplant Network Position Statement provides evidence-based, expert panel recommendations with values and preferences, and practical tips on: (1) patient selection criteria; (2) selected patient populations; and (3) post transplantation surveillance. The recommendations were developed through systematic review of the literature and using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. The evolving areas of importance addressed include transplant recipient age, frailty assessment, pulmonary hypertension evaluation, cannabis use, combined heart and other solid organ transplantation, adult congenital heart disease, cardiac amyloidosis, high sensitization, and post-transplantation management of antibodies to human leukocyte antigen, rejection, cardiac allograft vasculopathy, and long-term noncardiac care. Attention is also given to Canadian-specific management strategies including the prioritization of highly sensitized transplant candidates (status 4S) and heart organ allocation algorithms. The focus topics in this position statement highlight the increased complexity of patients who undergo evaluation for heart transplantation as well as improved patient selection, and advances in post-transplantation management and surveillance that have led to better long-term outcomes for heart transplant recipients.

Mammalian target of rapamycin (mTOR) inhibitors and skin cancer risk in nonrenal solid organ transplant recipients: systematic review and meta-analysis

BACKGROUND

Solid organ transplant recipients have an increased risk of malignancy compared with the general population. Mammalian target of rapamycin (mTOR) inhibitors have been used as immunosuppressants in transplant recipients. There remains a lack of evidence of this treatment in nonrenal solid organ transplantation. We aimed to perform a systematic review and meta-analysis to assess the effects of mTOR inhibitors on secondary nonmelanoma skin cancer (NMSC) malignancies in nonrenal transplant recipients.

METHODS

A systematic review and meta-analysis was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Eligible studies for the present systematic review and meta-analysis included those in which patient cohorts underwent heart, liver, lung, and pancreas (i.e. nonrenal solid organ) transplantation, with treatment group being those treated with an mTOR inhibitor such as sirolimus or everolimus, and control group being placebo, or alternative non-mTOR inhibitor treatment such as calcineurin inhibitors or as per standard treatment protocol.

RESULTS

From the six included studies, we found no significant difference in the odds of either primary or secondary NMSC (OR 0.73, 95% CI 0.41-1.29, P = 0.28). Pooled analysis of patients with secondary NMSC demonstrated a trend toward significant benefit with mTOR inhibitor treatment (OR 0.61, 95% CI 0.37-1.02, P = 0.06) but no protective effect for primary NMSC (OR 0.53, 95% CI 0.03-9.96, P = 0.67).

CONCLUSIONS

Our results suggest that in nonrenal transplant recipients, mTOR inhibitors may have a protective effect against secondary NMSC but not primary NMSC posttransplantation. Extrapolating the findings of reduced NMSC in renal transplant populations to nonrenal transplant cases should be cautioned.

Temporal Trends of De Novo Malignancy Development After Heart Transplantation

BACKGROUND

Malignancy is a concern in cardiac transplant recipients, but the temporal trends of de novo malignancy development are unknown.

OBJECTIVES

The goal of this study was to describe the temporal trends of the incidence, types, and predictors of de novo malignancy in cardiac transplant recipients.

METHODS

The authors analyzed the temporal trends of post-transplant incidence, types, and predictors of malignancy using 17,587 primary adult heart-only transplant recipients from the International Society for Heart and Lung Transplantation registry. The main study outcomes included the incidence of, types of, and time to de novo malignancy.

RESULTS

The risk of any de novo solid malignancy between years 1 and 5 after transplantation was 10.7%. The cumulative incidence by malignancy type was: skin cancer (7.0%), non-skin solid cancer (4.0%), and lymphoproliferative disorders (0.9%). There was no temporal difference in the time to development according to malignancy type. However, the cumulative incidence of de novo solid malignancy increased from 2000 to 2005 vs. 2006 to 2011 (10.0% vs. 12.4%; p < 0.0001). Survival in patients after de novo malignancy was markedly lower than in patients without malignancy (p < 0.0001). Older recipients and patients who underwent transplantation in the recent era had a higher risk of de novo malignancy.

CONCLUSIONS

More than 10% of adult heart transplant recipients developed de novo malignancy between years 1 and 5 after transplantation, and this outcome was associated with increased mortality. The incidence of post-transplant de novo solid malignancy increased temporally, with the largest increase in skin cancer. Individualized immunosuppression strategies and enhanced cancer screening should be studied to determine whether they can reduce the adverse outcomes of post-transplantation malignancy.

Cancer incidence and mortality after heart transplantation - A population-based national cohort study

Background: Cancer is currently one of the most important factors affecting the long-term health and survival of heart transplant patients. Material and methods: We calculated the standardized incidence ratios (SIR) for different cancer sites and the cancer-specific standardized mortality ratio (SMR) by linking a cohort of 479 adult heart transplant recipients transplanted in 1985-2014 (4491.6 person-years of follow-up) with data from the national Finnish Cancer Registry until the end of 2015, and with the data from the Statistics Finland's national registry of causes of death. Results: A total of 267 cancers occurred in 143 patients (SIR 6.0; 95% confidence interval (CI) 5.3-6.7). The SIR for overall cancer was considerably higher for men (SIR 6.7; 95% CI 5.9-7.5) than for women (1.4; 95% CI 0.6-2.6). Most frequent cancers were non-melanoma skin cancers (basal cell carcinoma 83 cases, squamous cell skin cancer (SCC) 56 cases), followed by Non-Hodgkin lymphoma (NHL) (36 cases), lung cancer (17), cancer of prostate (16) and cancer of kidney (12). SIRs were highest for SCC (51.9; 95% CI 39.2-67.4), lip cancer (47.4; 95% CI 19.1-97.7), cancer of tongue (26.3; 95% CI 7.2-67.4), and NHL (25.7; 95% CI 18.0-35.6). For most cancers, SIRs increased steadily by time since transplantation. Cancer mortality was three times higher for heart transplant recipients than for the population (SMR 3.1; 95% CI 2.1-4.1). Conclusions: Both cancer incidence and mortality are remarkably increased after heart transplantation, with the relative incidence most elevated for SCC, lip and other oral cancers, and for NHL.

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.

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.

Long-term use of amiodarone before heart transplantation significantly reduces early post-transplant atrial fibrillation and is not associated with increased mortality after heart transplantation

Background

Amiodarone is a frequently used antiarrhythmic drug in patients with end-stage heart failure. Given its long half-life, pre-transplant use of amiodarone has been controversially discussed, with divergent results regarding morbidity and mortality after heart transplantation (HTX).

Aim

The aim of this study was to investigate the effects of long-term use of amiodarone before HTX on early post-transplant atrial fibrillation (AF) and mortality after HTX.

Methods

Five hundred and thirty patients (age ≥18 years) receiving HTX between June 1989 and December 2012 were included in this retrospective single-center study. Patients with long-term use of amiodarone before HTX (≥1 year) were compared to those without long-term use (none or <1 year of amiodarone). Primary outcomes were early post-transplant AF and mortality after HTX. The Kaplan–Meier estimator using log-rank tests was applied for freedom from early post-transplant AF and survival.

Results

Of the 530 patients, 74 (14.0%) received long-term amiodarone therapy, with a mean duration of 32.3±26.3 months. Mean daily dose was 223.0±75.0 mg. Indications included AF, Wolff–Parkinson–White syndrome, ventricular tachycardia, and ventricular fibrillation. Patients with long-term use of amiodarone before HTX had significantly lower rates of early post-transplant AF (P=0.0105). Further, Kaplan–Meier analysis of freedom from early post-transplant AF showed significantly lower rates of AF in this group (P=0.0123). There was no statistically significant difference between patients with and without long-term use of amiodarone prior to HTX in 1-year (P=0.8596), 2-year (P=0.8620), 5-year (P=0.2737), or overall follow-up mortality after HTX (P=0.1049). Moreover, Kaplan–Meier survival analysis showed no statistically significant difference in overall survival (P=0.1786).

Conclusion

Long-term use of amiodarone in patients before HTX significantly reduces early post-transplant AF and is not associated with increased mortality after HTX.

Review on immunosuppression in liver transplantation

The optimal level of immunosuppression in solid organ transplantation, in particular for the liver, is a delicate balance between the benefit of preventing rejection and the adverse side effects of immunosuppression. There is uncertainty about when this level is achieved in any individual recipient. Immunosuppression regimens vary between individual centers and changes with time as new agents and data are available. Presently concerns about the adverse side effects of calcineurin inhibitor, the main class of immunosuppressive agents used in liver transplantation (LT), has led to consideration of the use of antibody induction therapies for patients at higher risk of developing adverse side effects. The longevity of the transplanted organ is potentially improved by better management of rejection episodes and special consideration for tailoring of immunosuppression to the individual with viral hepatitis C, hepatocellular carcinoma or pregnancy. This review provides an overview of the current strategies for post LT immunosuppression and discusses modifications to consider for special patient populations.

Analysis of malignancies in patients after heart transplantation with subsequent immunosuppressive therapy

Objective

The aim of this study was to analyze the distribution of malignancies in patients after heart transplantation (HTX) and to evaluate the risk factors including immunosuppressive therapy with regard to the development of malignancies and survival. Special emphasis was placed on the effects of a mammalian target of rapamycin (mTOR) containing immunosuppressive regimen.

Methods

A total of 381 patients (age ≥18 years) receiving HTX were included in the present analysis. All patients were followed-up at the University of Heidelberg Heart Center, Heidelberg, Germany. Data were retrieved from the Heidelberg Registry for Heart Transplantation being collected between 1989 and 2014. According to center standard, all patients received induction therapy with anti-thymocyte globulin guided by T-cell monitoring since 1994. The initial immunosuppressive regimen consisting of cyclosporine A (CsA) and azathioprine (AZA) was replaced by CsA and mycophenolate mofetil (MMF) in 2001 and by tacrolimus (TAC) and MMF in 2006. Additionally, mTOR inhibitors (everolimus/sirolimus) were applied since 2003.

Results

Mean recipient age at HTX was 51.2±10.5 years and the mean follow-up period after HTX was 9.7±5.9 years. During follow-up, 130 patients developed a neoplasm (34.1% of total). Subgroup analysis revealed 58 patients with cutaneous malignancy only (15.2%), 56 patients with noncutaneous malignancy only (14.7%), and 16 patients with both cutaneous and noncutaneous malignancy (4.2%). Statistically significant risk factors associated with an increased risk of malignancy after HTX were older age (P<0.0001), male recipients (P=0.0008), dyslipidemia (P=0.0263), diabetes mellitus (P=0.0003), renal insufficiency (P=0.0247), and >1 treated rejection episode (TRE) in the first year after HTX (P=0.0091). Administration of CsA (P=0.0195), AZA (P=0.0008), or steroids (P=0.0018) for >1 year after HTX was associated with increased development of malignancy, whereas administration of MMF (P<0.0001) or mTOR inhibitors (P<0.0001) was associated with a lower risk for development of malignancy. Additionally, 5-year follow-up of cutaneous malignancy recurrence (P=0.0065) and noncutaneous malignancy mortality (P=0.0011) was significantly lower in patients receiving an mTOR inhibitor containing therapy after the development of a malignancy.

Conclusion

This study highlights the complexity of risk factors including immunosuppression with regard to the development of malignancies after HTX. mTOR-inhibitor-based immunosuppression is associated with a better outcome after HTX, particularly in cases with noncutaneous malignancy.

Coronary microvasculopathy in heart transplantation: Consequences and therapeutic implications

Despite the progress made in the prevention and treatment of rejection of the transplanted heart, cardiac allograft vasculopathy (CAV) remains the main cause of death in late survival transplanted patients. CAV consists of a progressive diffuse intimal hyperplasia and the proliferation of vascular smooth muscle cells, ending in wall thickening of epicardial vessels, intramyocardial arteries (50-20 μm), arterioles (20-10 μm), and capillaries (< 10 μm). The etiology of CAV remains unclear; both immunologic and non-immunologic mechanisms contribute to endothelial damage with a sustained inflammatory response. The immunological factors involved are Human Leukocyte Antigen compatibility between donor and recipient, alloreactive T cells and the humoral immune system. The non-immunological factors are older donor age, ischemia-reperfusion time, hyperlipidemia and CMV infections. Diagnostic techniques that are able to assess microvascular function are lacking. Intravascular ultrasound and fractional flow reserve, when performed during coronary angiography, are able to detect epicardial coronary artery disease but are not sensitive enough to assess microvascular changes. Some authors have proposed an index of microcirculatory resistance during maximal hyperemia, which is calculated by dividing pressure by flow (distal pressure multiplied by the hyperemic mean transit time). Non-invasive methods to assess coronary physiology are stress echocardiography, coronary flow reserve by transthoracic Doppler echocardiography, single photon emission computed tomography, and perfusion cardiac magnetic resonance. In this review, we intend to analyze the mechanisms, consequences and therapeutic implications of microvascular dysfunction, including an extended citation of relevant literature data.

Pharmacology and toxicology of mycophenolate in organ transplant recipients: an update

This review aims to provide an update of the literature on the pharmacology and toxicology of mycophenolate in solid organ transplant recipients. Mycophenolate is now the antimetabolite of choice in immunosuppressant regimens in transplant recipients. The active drug moiety mycophenolic acid (MPA) is available as an ester pro-drug and an enteric-coated sodium salt. MPA is a competitive, selective and reversible inhibitor of inosine-5'-monophosphate dehydrogenase (IMPDH), an important rate-limiting enzyme in purine synthesis. MPA suppresses T and B lymphocyte proliferation; it also decreases expression of glycoproteins and adhesion molecules responsible for recruiting monocytes and lymphocytes to sites of inflammation and graft rejection; and may destroy activated lymphocytes by induction of a necrotic signal. Improved long-term allograft survival has been demonstrated for MPA and may be due to inhibition of monocyte chemoattractant protein 1 or fibroblast proliferation. Recent research also suggested a differential effect of mycophenolate on the regulatory T cell/helper T cell balance which could potentially encourage immune tolerance. Lower exposure to calcineurin inhibitors (renal sparing) appears to be possible with concomitant use of MPA in renal transplant recipients without undue risk of rejection. MPA displays large between- and within-subject pharmacokinetic variability. At least three studies have now reported that MPA exhibits nonlinear pharmacokinetics, with bioavailability decreasing significantly with increasing doses, perhaps due to saturable absorption processes or saturable enterohepatic recirculation. The role of therapeutic drug monitoring (TDM) is still controversial and the ability of routine MPA TDM to improve long-term graft survival and patient outcomes is largely unknown. MPA monitoring may be more important in high-immunological recipients, those on calcineurin-inhibitor-sparing regimens and in whom unexpected rejection or infections have occurred. The majority of pharmacodynamic data on MPA has been obtained in patients receiving MMF therapy in the first year after kidney transplantation. Low MPA area under the concentration time from 0 to 12 h post-dose (AUC0-12) is associated with increased incidence of biopsy-proven acute rejection although AUC0-12 optimal cut-off values vary across study populations. IMPDH monitoring to identify individuals at increased risk of rejection shows some promise but is still in the experimental stage. A relationship between MPA exposure and adverse events was identified in some but not all studies. Genetic variants within genes involved in MPA metabolism (UGT1A9, UGT1A8, UGT2B7), cellular transportation (SLCOB1, SLCO1B3, ABCC2) and targets (IMPDH) have been reported to effect MPA pharmacokinetics and/or response in some studies; however, larger studies across different ethnic groups that take into account genetic linkage and drug interactions that can alter a patient's phenotype are needed before any clinical recommendations based on patient genotype can be formulated. There is little data on the pharmacology and toxicology of MPA in older and paediatric transplant recipients.

The Role of mTOR Inhibitors in Liver Transplantation: Reviewing the Evidence

Despite the success of liver transplantation, long-term complications remain, including de novo malignancies, metabolic syndrome, and the recurrence of hepatitis C virus (HCV) and hepatocellular carcinoma (HCC). The current mainstay of treatment, calcineurin inhibitors (CNIs), can also worsen posttransplant renal dysfunction, neurotoxicity, and diabetes. Clearly there is a need for better immunosuppressive agents that maintain similar rates of efficacy and renal function whilst minimizing adverse effects. The mammalian target of rapamycin (mTOR) inhibitors with a mechanism of action that is different from other immunosuppressive agents has the potential to address some of these issues. In this review we surveyed the literature for reports of the use of mTOR inhibitors in adult liver transplantation with respect to renal function, efficacy, safety, neurological symptoms, de novo tumors, and the recurrence of HCC and HCV. The results of our review indicate that mTOR inhibitors are associated with efficacy comparable to CNIs while having benefits on renal function in liver transplantation. We also consider newer dosing schedules that may limit side effects. Finally, we discuss evidence that mTOR inhibitors may have benefits in the oncology setting and in relation to HCV-related allograft fibrosis, metabolic syndrome, and neurotoxicity.

Rejection after conversion to a proliferation signal inhibitor in chronic heart transplantation

We sought to determine the incidence, risk factors, and consequences of acute rejection (AR) after conversion from a calcineurin inhibitor (CNI) to a proliferation signal inhibitor (PSI) in maintenance heart transplantation. Relevant clinical data were retrospectively obtained for 284 long-term heart transplant recipients from nine centers in whom CNIs were replaced with a PSI (sirolimus or everolimus) between October 2001 and March 2009. The rejection rate at one yr was 8.3%, stabilizing to 2% per year thereafter. The incidence rate after conversion (4.9 per 100 patient-years) was significantly higher than that observed on CNI therapy in the pre-conversion period (2.2 per 100 patient-years). By multivariate analysis, rejection risk was associated with a history of late AR prior to PSI conversion, early conversion (<5 yr) after transplantation and age <50 yr at the time of conversion. Use of mycophenolate mofetil was a protective factor. Post-conversion rejection did not significantly influence the evolution of left ventricular ejection fraction, renal function, or mortality during further follow-up. Conversion to a CNI-free immunosuppression based on a PSI results in an increased risk of AR. Awareness of the clinical determinants of post-conversion rejection could help to refine the current PSI conversion strategies.

HLA compatibility index: does it have a role in patients after heart transplantation?

AIMS

To determine the impact of HLA compatibility measured by the Compatibility Index, on survival, rate of rejections, malignancies and infections in patients after heart transplantation (HTx).

METHODS

We carried out a retrospective analysis of 182 consecutive patients who underwent heart transplantation in our center from January 2001 to April 2010. According to degree of HLA-A, B and DR matching (Compatibility Index, CI) the patients were divided in two groups, Group A (n=83) with an IC 0-17 and group B (n=99) with an IC 18-26. There was no significant difference in demographic parameters between recipients and donors.

RESULTS

We found no difference in rates of rejections or infections between Group A and Group B (AR: 22 (26.5%) vs. 34 (34.3%), P=0.2539; infections: 21 (25.3%) vs. 27 (27%) P=0.7637). The distribution of infections in terms of type (bacterial, viral, fungal, including Aspergillus) was similar in both groups. The incidence of malignant tumours was infrequent (3 (3.6%) vs. 4 (4.0%), P=0.8817). We found trend toward lower level of tacrolimus in Group A. Long term survival was similar in both groups.

CONCLUSIONS

Based on the results of our single-center trial, we found no impact of higher degree of HLA-A,-B, and -DR matching on survival, rejection episodes or infection. Further large studies are necessary to confirm our hypothesis that subjects with better HLA compatibility could require lower dose immunosuppression.

Management of non-melanoma skin cancer in immunocompromised solid organ transplant recipients

The management of non-melanoma skin cancers (NMSCs) in solid organ transplant recipients (OTRs) presents a variety of clinical challenges for physicians. OTRs are at a 65-fold increased risk for developing cutaneous squamous cell carcinomas (SCC), the most common NMSC that develops after transplantation. Risk factors contributing to the development of NMSCs in OTRs include a past medical history of any previous skin cancer, a personal history of significant sun exposure and a fair skin complexion or phototype. Further, greater immunosuppressive medication levels lead to an increased risk of NMSCs. Among immunosuppressants, specific older agents such as azathioprine and cyclosporine may increase the risk of developing NMSCs in contrast to newer agents such as sirolimus. Early skin biopsy and treatment of premalignant and malignant lesions are essential for treating these patients successfully. In this regard, the concept of field cancerization has been instructive in broadening treatments to include entire affected areas rather than individual lesions given that the areas with significant ultraviolet irradiation will continue to develop numerous individual precancerous and cancerous lesions. Field therapy with photodynamic therapy or topical 5-fluorouracil, imiquimod or diclofenac is often used in OTRs according to individual patient tolerability. Prompt excision or Mohs micrographic surgery is the standard of care of primary, uncomplicated squamous cell and basal cell carcinomas. For patients with in-transit or metastatic squamous cell carcinomas, adjuvant radiation, chemotherapy, and staging by sentinel lymph node dissection may be employed. For patients who develop numerous SCC per year, chemoprophylaxis can be effective in limiting the burden of disease. In consultation with the multidisciplinary transplant team, the immunosuppressive regimen can be revised to lower overall immunosuppression or altered to include newer drugs that have decreased oncogenic potential in OTRs. The greatest impact may be made by the prevention of NMSCs through simple, but rigorous, patient education on the benefits of UV protection, periodic self-skin examinations, and regular follow-ups. Accordingly, vitamin D and calcium supplementation should also be incorporated in transplant recipients. Management of OTRs requires patient education, frequent motivation for vigilance, regular follow-up, and interdisciplinary collaboration between transplant surgeons, nephrologists, hepatologists, cardiologists, transplant nurses, dermatologists, oncologists, pharmacists, and other relevant physicians ideally orchestrated by the essential transplant coordinators.

Proliferation signal inhibitors and post-transplant malignancies in heart transplantation: practical clinical management questions

Although malignancy is a major threat to long-term survival of heart transplant (HT) recipients, clear strategies to manage immunosuppression in these patients are lacking. Several lines of evidences support the hypothesis of an anticancer effect of proliferation signal inhibitors (PSIs: mammalian target of rapamycin [mTOR] inhibitors) in HT recipients. This property may arise from PSI's ability to replace immunosuppressive therapies that promote cancer progression, such as calcineurin inhibitors or azathioprine, and/or through their direct biological actions in preventing tumor development and progression. Given the lack of randomized studies specifically exploring these issues in the transplant setting, a collaborative group reviewed current literature and personal clinical experience to reach a consensus aimed to provide practical guidance for the clinical conduct in HT recipients with malignancy, or at high risk of malignancy, with a special focus on advice relevant to potential role of PSIs.