Long-Term Risk of Cancer in Survivors of Pediatric ESRD

BACKGROUND AND OBJECTIVES

ESRD is associated with an increased risk of malignancies. We analyzed the incidence of cancer in patients with pediatric ESRD after long-term follow-up.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

All Dutch patients born before 1979 who were transplanted at age <15 years old in 1972-1992 were followed until 2010. We explored type and incidence of malignancies in patients compared with the general population using the National Cancer Registry.

RESULTS

After a median of 25.3 years (1.3-37.8) of transplantation and at a median age of 33.5 years old (11.0-49.0), 105 primary malignancies had occurred in 54 of 249 patients. Among them, cutaneous squamous cell carcinoma was most frequent. Patients ages 25-30 years old had developed 16.5 times (95% confidence interval, 7.9 to 34.6) as many de novo tumors and 991 times (95% confidence interval, 313 to 3137) as many de novo cutaneous squamous cell carcinomas as their general population counterparts; in survivors ages 45-50 years old, these numbers were 81.5 (95% confidence interval, 50.7 to 131.1) and 2610 (95% confidence interval, 1596 to 4267), respectively. Cumulative incidence competing risk analysis showed that, after 30 years of transplantation, 41% of the survivors had developed cancer; 31% had developed a second de novo cancer <1 year after initial cancer diagnosis.

CONCLUSIONS

Cancer is highly prevalent among patients with pediatric ESRD after 25.3 years of transplantation, with a high rate of recurrence.

A randomized trial of everolimus and low-dose cyclosporine in renal transplantation: with or without steroids?

This multicenter, randomized, prospective, controlled trial (EVIDENCE study) aimed to determine short-term effects of early steroid withdrawal in renal transplant patients initially treated with everolimus, low-dose cyclosporine (CsA), and steroids. Patients were randomized to standard triple therapy with CsA, everolimus twice daily and steroids (group A), steroid-free immunosuppression (group B), or triple therapy once daily (group C). However, since patient enrollment was slower than expected, group C randomization was prematurely discontinued. The primary end point was treatment failure rate (composite end point of death, graft loss, biopsy-proven acute rejection, and loss to follow-up) between randomization and month 12. Patients evaluable for the primary end point included 139 randomized patients. According to intention-to-treat analysis, 2.8% of patients in group A and 14.7% in group B experienced treatment failure (95% upper confidence limit 19.7%). As this was higher than the predefined noninferiority limit of 10%, noninferiority could not be proved. No conclusive statements can be made on noninferiority of the steroid withdrawal regimen vs the standard regimen in these patients. Additional studies with longer follow-up are required to determine the efficacy of steroid-free immunosuppression in renal transplant recipients receiving everolimus.

Histiocytic sarcoma; case report of a rare disease in a kidney transplant recipient

BACKGROUND

Histiocytic sarcoma (HS) is a rare hematologic neoplasm with a few hundred cases having been described to date.

CASE PRESENTATION

We report the case of a 56-year-old woman with a history of hepatitis C infection and chronic kidney disease (CKD), submitted to a kidney transplant in 1984, under maintenance immunosuppression with prednisone and azathioprine. Patient presented with a relentlessly growing mass on her right front thorax. It was painless, smooth, and adherent to the deep muscle. Laboratory studies were unremarkable. Ultrasonography and computerized tomography (CT) scan revealed a highly vascularized heterogeneous mass (8×9 cm), with a necrotic centre. Positron emission tomography (PET) scan demonstrated multiple thoracic, abdominal, and pelvic nodules. Histology revealed a highly undifferentiated HS (vimentin, CD68, CD99, and CD4 positive). In spite of having started treatment with etoposide and thalidomide, no clinical response was achieved and the patient died three months later.

CONCLUSIONS

To the authors' knowledge, this is the first described case of HS in a solid organ transplant patient.

Diagnosis and management of ureteral complications following renal transplantation

When compared with maintenance dialysis, renal transplantation affords patients with end-stage renal disease better long-term survival and a better quality of life. Approximately 9% of patients will develop a major urologic complication following kidney transplantation. Ureteral complications are most common and include obstruction (intrinsic and extrinsic), urine leak and vesicoureteral reflux. Ureterovesical anastomotic strictures result from technical error or ureteral ischemia. Balloon dilation or endoureterotomy may be considered for short, low-grade strictures, but open reconstruction is associated with higher success rates. Urine leak usually occurs in the early postoperative period. Nearly 60% of patients can be successfully managed with a pelvic drain and urinary decompression (nephrostomy tube, ureteral stent, and indwelling bladder catheter). Proximal, large-volume, or leaks that persist despite urinary diversion, require open repair. Vesicoureteral reflux is common following transplantation. Patients with recurrent pyelonephritis despite antimicrobial prophylaxis require surgical treatment. Deflux injection may be considered in recipients with low-grade disease. Grade IV and V reflux are best managed with open reconstruction.

Post-transplant lymphoproliferative disorders: from epidemiology to pathogenesis-driven treatment

Post-transplant lymphoproliferative disorders (PTLDs) represent the most severe complication of both solid organ and hematopoietic stem cell transplantation. The Epstein-Barr Virus (EBV) is the main driver of PTLD, particularly those occurring early after transplantation. EBV-driven malignancies are associated with selective expression of latent viral proteins, but uncontrolled lytic replication may favor early phases of cell transformation. Besides immunodepression, persistent immune activation and chronic inflammation play an important role in both virus reactivation and expansion of EBV-infected B cells. EBV-induced immortalization requires the expression of telomerase. TERT, the rate-limiting component of the telomerase complex, is central in the switch from the lytic to the latent viral program, and TERT inhibition induces the EBV lytic cycle and cell death. Immunotherapy and combination of EBV lytic cycle inducers with antiviral drugs are promising strategies to improve the treatment of PTLD patients. This review is aimed at providing an update on the intriguing association between EBV and PTLD, mainly focusing on cases arising after kidney and liver transplantation, which account for the vast majority of transplants.

Renal cancer in kidney transplanted patients

Renal cancer occurs more frequently in renal transplanted patients than in the general population, affecting native kidneys in 90% of cases and the graft in 10 %. In addition to general risk factors, malignancy susceptibility may be influenced by immunosuppressive therapy, the use of calcineurin inhibitors (CNI) as compared with mammalian target of rapamycin inhibitors, and the length of dialysis treatment. Acquired cystic kidney disease may increase the risk for renal cancer after transplantation, while autosomal dominant polycystic kidney disease does not seem to predispose to cancer development. Annual ultrasound evaluation seems appropriate in patients with congenital or acquired cystic disease or even a single cyst in native kidneys, and every 2 years in patients older than 60 years if they were on dialysis for more than 5 years before transplantation. Immunosuppression should be lowered in patients who develop renal cancer, by reduction or withdrawal of CNI. Although more evidence is still needed, it seems reasonable to shift patients from CNI to everolimus or sirolimus if not already treated with one of these drugs, with due caution in subjects with chronic allograft nephropathy.

Management and prevention of post-transplant malignancies in kidney transplant recipients

The central issue in organ transplantation remains suppression of allograft rejection. Thus, the development of immunosuppressive drugs has been the key to successful allograft function. The increased immunosuppressive efficiency obtained in the last two decades in kidney transplantation dramatically reduced the incidence of acute rejection. However, the inevitable trade-off was an increased rate of post-transplant infections and malignancies. Since the incidence of cancer in immunosuppressed transplant recipients becomes greater over time, and the introduction of new immunosuppressive strategies are expected to extend significantly allograft survival, the problem might grow exponentially in the near future. Thus, cancer is becoming a major cause of morbidity and mortality in patients otherwise successfully treated by organ transplantation. There are at least four distinct areas requiring consideration, which have a potentially serious impact on recipient outcome after transplantation: (i) the risk of transmitting a malignancy to the recipient within the donor organ; (ii) the problems of previously diagnosed and treated malignancy in the recipient; (iii) the prevention of de novo post-transplant malignant diseases and (iv) the management of these complex and often life-threatening clinical problems. In this scenario, the direct and indirect oncogenic potential of immunosuppressive therapy should be always carefully considered.

Immunosuppression and Multiple Primary Malignancies in Kidney-Transplanted Patients: A Single-Institute Study

Immunodeficiency is associated with higher cancer incidence. However, it is unknown whether there is a link between immunodeficiency and development of multiple primary malignancies. In the present study we analyse this link focusing on kidney-transplanted patients, as they are at higher risk of developing cancer due to the chronic assumption of immunosuppressants. We followed up 1200 patients who underwent kidney transplantation between 1980 and 2012. A total of 77/1200 kidney-transplanted patients developed cancer and 24 of them developed multiple cancers. Most multiple cancers were synchronous with a nonsignificant association between cancer and rejection episodes. In the general cancer population, one-ninth of patients are at higher risk of developing a second tumor over a lifetime; hence it would be reasonable to conclude that, from a merely theoretical and statistical viewpoint, long-term transplanted patients potentially have a higher risk of developing MPMs. However, data did not confirm this assumption, probably because these patients die before a second primary malignancy appears. Despite many observations on the increased incidence of different tumor types in immunodeficient patients and despite immunosuppression certainly being a predisposing factor for the multicancer syndrome, data so far are not robust enough to justify a correlation between immunodeficiency and multiple primary malignancies in transplanted patients.

Early diagnosis and treatment of breast cancer in Japanese kidney transplant recipients: a single center experience

Background

The incidence of malignancies in kidney transplant recipients is increasing. Breast cancer is a common malignancy after kidney transplantation and can be more aggressive in kidney transplant recipients than in the general population. In this study, we evaluated the incidence and prognosis of breast cancer in kidney transplant recipients.

Findings

Between 1993 and 2013, 750 kidney transplant patients were followed-up at our center. Since 1999, annual physical examination, mammography, and breast ultrasonography have been performed for such patients. Diagnostic studies, including core needle or mammotome biopsy, were performed for suspected malignancies. Patients with malignant neoplasm were administered the appropriate treatment and followed-up to assess tumor response and symptoms.

Nine patients were diagnosed with breast cancer during the follow-up period. The mean age at the initial detection of the breast cancer was 47.7 ± 8.4 years. The mean interval from transplantation to diagnosis was 148.7 ± 37.1 months. Of the 9 patients, 8 were detected through the screening test; 7 were treated with breast conservative surgery and 1 was treated with modified radical mastectomy. The cancer stages were 0 (n = 2), I (n = 6), and II (n = 1). The incidence of breast cancer tended to be unchanged with time between transplantation and diagnosis, inconsistent with the increase in the duration of immunosuppression.

Conclusion

Annual screening tests are crucial in the early diagnosis of breast cancer. Early treatment of breast cancer can result in an excellent prognosis in kidney transplant recipients.

Clinical and Genetic Factors Associated with Cutaneous Squamous Cell Carcinoma in Kidney and Heart Transplant Recipients

BACKGROUND

Cutaneous squamous cell carcinoma (cSCC) occurs with higher frequency and recurrence rates, increased morbidity and mortality, and more aggressive metastasis in kidney and heart transplant recipients compared to the general population but all transplant recipients do not develop cSCC. In addition, the phenotypic expression of cSCC among transplant recipients can vary between mild disease to extensive recurrent metastatic disease. These clinically observed differences in occurrence and severity of cSCC among transplant recipients suggest the possibility that an underlying genetic component might modify risk.

METHODS

We identified 88 white post-transplant cSCC cases (71 kidney and 17 heart) and 300 white post-transplant controls (265 kidney and 35 heart) using a DNA biobank linked with de-identified electronic medical records. Logistic regression was used to determine adjusted odds ratios (OR) for clinical characteristics and single nucleotide polymorphisms (SNP) associated with cSCC in both a candidate SNP and genome wide analysis.

RESULTS

Age (OR 1.08 [1.05-1.11], p<0.001) and azathioprine exposure (OR 8.64 [3.92-19.03], p<0.001) were significantly associated while gender, smoking tobacco use, dialysis duration and immunosuppression duration were not. Ten candidate SNPs previously associated with non-melanoma skin cancer in the general population were significantly associated with cSCC in transplant recipients. Genome wide association analysis implicated SNPs in genes previously associated with malignancy, CSMD1 (OR 3.14 [1.90-5.20]) and CACNA1D (OR 2.67 [1.73-4.10]).

CONCLUSIONS

This study shows an association of increasing age and azathioprine exposure with cSCC and confirms a genetic contribution for cSCC development in kidney and heart transplant recipients.

The effects of drugs with immunosuppressive or immunomodulatory activities on xenobiotics-metabolizing enzymes expression in primary human hepatocytes

In this paper we investigated the effects of several drugs used in transplant medicine, i.e. cyclosporine A, tacrolimus, rapamycin, everolimus, mycophenolate mofetil, fluvastatin and rosuvastatin, on the expression of major drug-metabolizing enzymes in human hepatocytes. Moreover, we tested the ability of these drugs to affect transcriptional activity of glucocorticoid (GR) and aryl hydrocarbon receptor (AhR). We found that most of tested compounds did not induce expression of CYP1A1/1A2/3A4/2A6/2B6/2C9 mRNAs in human hepatocytes. Slight induction was observed for CYP2A6/2C9 mRNAs and CYP2A6 protein in the rapamycin-treated hepatocytes. Decrease of CYP2A6 and CYP2B6 proteins was observed in rosuvastatin-treated cells. Mycophenolate mofetil antagonized the effects of dexamethasone on GR but it potentiated the action of dioxin on AhR. Induction of CYP1A1 mRNA in HepG2 cells by dioxin was modestly antagonized by mycophenolate mofetil, while the induction by benzo[a]pyren or S-omeprazole was significantly potentiated by this drug. In general, tested compounds can be considered safe in the terms of possible drug-drug interaction caused by induction of drug-metabolizing cytochromes P450. Nevertheless, mycophenolate mofetil is of possible concern and its combination with drugs, environmental pollutants or food constituents, which activate AhR, may represent a significant toxicological risk.

Epidemiology of head and neck cancer

This article discusses risk factors, incidence trends, and prognostic considerations for head and neck cancer (HNC). The primary causes of HNC are tobacco and alcohol use, and human papillomavirus (HPV). Tobacco-related HNC incidence rates are decreasing in countries where tobacco use has declined. HPV-HNC, which occurs primarily in the oropharynx and is associated with sexual behaviors, has been increasing over the past several decades, among white men in particular. The prognosis for HNC overall has improved slightly since the 1990s, and is influenced by site, stage, and HPV status. Prognosis for HPV-HNC is significantly better than for HPV-negative disease.

[Management of side effects of targeted therapies in renal cancer: sexual disorders]

Since sexual disorders were not specifically studied in the principal series, epidemiological data is scarce. Nevertheless, in practice, when sexuality is dealt with during the monitoring of patients undergoing targeted therapies, more than half of the patients questioned say that they attach importance to their quality of sex life, despite the severity of their metastatic renal cancer. At the start of treatment, it is therefore important to inform patients of the possible occurrence of problems and to encourage them to report them. During treatment, screening for sexual disorders by questioning is desirable: desire, lubrication, dyspareunia, erectile dysfunction. In the event of the onset of a sexual disorder during treatment, it is not usually necessary to stop or modify the treatment. Therapeutic measures depend on the discomfort felt and are under the control of the specialist: erectile dysfunction, male libido disorders, vaginal dryness and vulvovaginitis. A consultation with an oncology psychologist and/or sex therapist is useful, if possible with the partner, based on the impact of the sexual problems.

Preconditioning donor livers with cromolyn or compound 48/80 prolongs recipient survival in a rat orthotopic liver transplantation model

BACKGROUND

Acute rejection (AR) remains a challenge in organ transplantation. Preconditioning donor organs can reduce AR and prolong survival. Whether preconditioning with cromolyn (CRM), a mast cell (MC) stabilizer, or compound 48/80 (CMP 48/80), a MC degranulator, can alleviate AR and prolong survival has not been studied.

METHODS

We used the male-DA-to-female-Lewis-rat orthotopic liver transplantation (OLT) model. Donors were preconditioned with CRM in a MC stabilizing way (CRM group) or CMP 48/80 in a MC depleting way (CMP 48/80 group). Rats preconditioned with phosphate-buffered saline were used as controls (PBS group). After preconditioning, OLT surgeries were carried out. OLT male-Lewis-to-female-Lewis-rats were used as the syngeneic group (syngeneic group).

RESULTS

Rats in the PBS group developed AR rapidly and died at 7.40 ± 1.14 days. Rats in the CRM and CMP 48/80 groups had significantly slower rejections and died at day 17.40 ± 1.67 or 14.20 ± 2.28, respectively (P < .05). Rats in the syngeneic group survived more than 60 days. Rejection activity indexes (RAIs) and liver functions were all alleviated through CRM or CMP 48/80 preconditioning. Interferon-γ messenger RNA (mRNA) expressions were reduced and interleukin-10 mRNA levels were higher in allografts in the CRM and CMP 48/80 groups, compared with the PBS group. These were confirmed by testing serum interferon-γ and interlerkin-10.

CONCLUSION

Preconditioning donor livers with CRM or CMP 48/80 can reduce AR and prolong survival of recipients after OLT.

Onco-nephrology: an appraisal of the cancer and chronic kidney disease links

A bidirectional relationship has been observed for kidney disease and cancer. On the one hand, cancer is an important complication noted in kidney disease as well as a major cause of morbidity and mortality in this group. On the other hand, improved cancer treatment has prolonged survival, but also increased the development of acute and chronic kidney disease. The combination of cancer and kidney disease makes it challenging for clinicians to provide comprehensive and safe therapies for this group of patients. As such, clinicians caring for this group must develop expertise and become competent in the practice of a newly evolving subspecialty of nephrology known as 'onco-nephrology'. This brief narrative review will focus on the cancer risk in patients with underlying kidney disease, the therapies such as erythropoiesis-stimulating agents on cancer progression and other outcomes, and the appropriate dosing of anti-cancer agents in patients with underlying kidney disease.

Prevalence and outcome of lung cancer in lung transplant recipients

BACKGROUND

Lung transplant is the only available therapy for patients with advanced lung disease. The goal of this study was to examine the prevalence, origin, management and outcome of lung cancer in recipients of lung transplant at our institution.

METHODS

After institutional review board approval, we conducted a retrospective chart review of all lung transplantations in our institution from January 1990 until June 2012.

RESULTS

The prevalence of lung cancer in the explanted lung was 6 (1.2%) of 462 and all cases were in subjects with lung fibrosis. All 4 subjects with lymph node involvement died of causes related to the malignancy. Nine (1.9%) of 462 patients were found to have bronchogenic carcinoma after lung transplant. The most common location was in the native lung in recipients of a single lung transplant (6 out of 9 patients). In one case, the tumor originated in the allograft and was potentially donor related. The median time to diagnosis after lung transplant was 28 months with a range from 9 months to 10 years. Median survival was 8 months, with tumors involving lymph nodes or distant metastases associated with a markedly worse prognosis (median survival 7 months) than stage I disease (median survival 27 months).

CONCLUSIONS

The prevalence of lung cancer in lung transplant recipients is low. Using accepted donor screening criteria, donor derived malignancy is exceptionally rare. While stage I disease is associated with improved survival in this cohort, survival is still not comparable to that of the general population, likely influenced by the need for aggressive immune suppression.

Implementation of guidelines for metabolic syndrome control in kidney transplant recipients: results at a single center

BACKGROUND

Cardiovascular disease is a leading cause of death among kidney transplant recipients. Metabolic syndrome increases the risk for cardiovascular events and decreases graft survival. Lately, guidelines for management of the metabolic syndrome, primarily hypertension, diabetes mellitus (DM) and hypercholesterolemia have dramatically changed in an attempt to decrease cardiovascular risks among kidney transplant recipients. In the present study we examined whether these guideline changes had impact on our management of post-transplantation patients and the subsequent treatment outcomes for these diseases.

METHODS

Data were obtained from kidney transplant clinic files from two follow-up (FU) periods-between 1994-1997 and between 2008-2011. Demographic data, monitoring and screening frequency for cardiovascular risk factors, immunosuppression regimen, treatment for hypertension, diabetes and hyperlipidemia, treatment outcomes and graft function changes were compared between the two follow-up periods.

RESULTS

There was a significant increase in the percentage of patients undergoing transplantation due to renal failure secondary to diabetes and/or hypertension. Patient monitoring and screening during the second FU period were less frequent, but more targeted, reflecting changes in clinic routines. Blood pressure was better controlled in the second FU period (p < 0.01), as was hypercholesterolemia (p < 0.001). High fasting glucose levels were more prevalent among patients in the second group (p < 0.005), although more patients received treatment for DM (p < 0.001). Significantly, fewer patients experienced deterioration of kidney functions during the second FU period (p < 0.001).

CONCLUSIONS

We found that guideline changes had impact on clinical practice, which translated to better control of the metabolic syndrome. DM control is challenging. Overall, stability of kidney function improved.

Conversion from calcineurin inhibitor-based immunosuppression to mammalian target of rapamycin inhibitors or belatacept in renal transplant recipients

The calcineurin inhibitors (CNIs) remain the standard of care for maintenance immunosuppression following renal transplantation. CNIs have demonstrated their effectiveness in reducing acute cellular rejection; however, some evidence suggests that these compounds negatively affect native renal function and are associated with allograft injury in renal transplant recipients. CNIs have also been linked with hypertension, new-onset diabetes after transplantation, tremor, and thrombotic microangiopathy, which have significant consequences for long-term allograft function and patient health overall. Thus, converting patients to a non-CNI-based regimen may improve renal function and also provide extrarenal benefits. A number of studies have been conducted that explore CNI conversion strategies in renal transplant recipients in an effort to improve long-term allograft function and survival. These include converting to alternative, non-nephrotoxic, maintenance immunosuppressants, such as the mammalian target of rapamycin inhibitors (sirolimus and everolimus) and the costimulation blocker belatacept. In this review of literature, evidence for the potential renal and extrarenal benefits of conversion to these non-CNI-based regimens is evaluated. Clinical challenges, including the adverse event profiles of non-CNI-based regimens and the selection of candidates for conversion, are also examined.

Inhibition of mammalian target of rapamycin signaling pathway decreases retinoic acid stimulated gene 8 expression in adult mouse testis

OBJECTIVE

To evaluate the expression of mammalian target of rapamycin (mTOR) pathway molecules in mouse spermatogenesis and as well as its role during proliferation and meiotic initiation of spermatogenic cells.

DESIGN

Experimental animal study.

SETTING

University.

ANIMAL(S)

C57Balb-C adult male mice.

INTERVENTION(S)

Expressions of mTOR signaling pathway proteins in adult testis were evaluated. Then the effect of inhibition of this pathway on proliferation and differentiation of spermatogonial stem cells was investigated using seminiferous tubule culture.

MAIN OUTCOME MEASURE(S)

Immunohistochemistry was performed to evaluate the expressions of mTOR signaling pathway proteins. To inhibit mTOR signaling pathway by rapamycin, seminiferous tubule culture was done. Viability assay and terminal deoxynucleotidyl transferase dUTP nick end labeling was performed to evaluate the culture conditions and to examine cell death, respectively. Western blot was used to determine the expressions of the PCNA, STRA8, and VASA proteins.

RESULT(S)

Our results showed that spermatogonial stem cells and preleptotene spermatocytes express total mTOR, p-mTOR, total p70S6K, p-p70S6K, and p-4EBP1. Expressions of p-p70S6K, p-4EBP1, PCNA, and STRA8 decreased significantly in the rapamycin-treated group, where no difference was observed in VASA expression. Cell viability and the number of apoptotic cells were similar for all groups.

CONCLUSION(S)

Our findings suggest that the mTOR signaling pathway may have role in the proliferation and stimulation of meiotic initiation of spermatogonial stem cells. To the best of our knowledge, this is the first ex vivo study that reports the function of the mTOR pathway in adult mouse spermatogenesis.

Malignancies after pediatric kidney transplantation: more than PTLD?

Post-transplant lymphoproliferative disease (PTLD) is the most frequent malignant complication of transplantation in childhood. Even with modern post-transplant immunosuppressive strategies, 1-2% of all kidney transplant recipients will develop PTLD within the first 5 years after transplantation, and the risk remains high even thereafter as long as immunosuppression is required. In addition to PTLD, adult kidney transplant recipients have an increased incidence of other immunosuppression-related malignancies, such as non-melanoma skin cancer or Kaposi's sarcoma. It is foreseeable that pediatric transplant recipients will face similar complications during their adult life. Not only immunosuppression but also other risk factors have been identified for some of these malignancies. Strategies addressing these risk factors during childhood may contribute to life-long cancer prevention. Furthermore, early recognition and regular screening may facilitate early diagnosis and treatment, thereby reducing transplant-related morbidity. In this review we focus on malignant complications after renal transplantation and discuss known risk factors. We also review current screening strategies for malignancies during post-transplant follow-up.

Epidemiology of de novo malignancies after solid-organ transplantation: immunosuppression, infection and other risk factors

Organ transplantation is an increasingly used medical procedure for treating otherwise fatal end-stage organ diseases, and a large number of anti-rejection drugs have been developed to prolong long-term survival of both the individual and the transplanted organ. However, the prolonged use of immunosuppressive drugs is well known to increase the risk of opportunistic diseases, particularly infections and virus-related malignancies. Although transplant recipients experience a nearly twofold elevated risk for all types of de novo cancers, persistent infections with oncogenic viruses are associated with up to hundredfold increased risks. Women of the reproductive age are growing in number among the recipients of solid-organ transplants, but specific data on cancer outcomes are lacking. This article updates evidences linking iatrogenic immunosuppression, persistent infections with oncogenic viruses, other risk factors and post-transplant malignancies. Epidemiological aspects, tumourigenesis related to oncogenic viruses, clinical implications, as well as primary and secondary prevention issues are discussed to offer clinicians and researchers alike an update of an increasingly important topic.

Management of pregnancy in the post-cardiac transplant patient

Over the past 10 years, heart transplantation survival has increased among transplant recipients. Because of improved outcomes in both congenital and adult transplant recipients, the number of male and female patients of childbearing age who desire pregnancy has also increased within this population. While there have been many successful pregnancies in post-cardiac transplant patients reported in the literature, long-term outcome data is limited. Decisions regarding the optimal timing and management of pregnancy in male and female post-cardiac transplant patients are challenging and should be coordinated by a multidisciplinary team of healthcare providers. Pregnant patients will need to be counseled and monitored carefully for complications including rejection, graft dysfunction, and infection. This review focuses on preconception counseling for both male and female cardiac transplant recipients. The maternal and fetal risks during pregnancy and the postpartum period, including risks to the fetus fathered by a male cardiac transplant recipient will be reviewed. It also provides a brief summary of our own transplant experience and recommendations for overall management of pregnancy in the post-cardiac transplant recipient.

Improved detection reveals active β-papillomavirus infection in skin lesions from kidney transplant recipients

The aim of this study was to determine whether detection of β-HPV gene products, as defined in epidermodysplasia verruciformis skin cancer, could also be observed in lesions from kidney transplant recipients alongside the viral DNA. A total of 111 samples, corresponding to 79 skin lesions abscised from 17 kidney transplant recipients, have been analyzed. The initial PCR analysis demonstrated that β-HPV-DNA was highly present in our tumor series (85%). Using a combination of antibodies raised against the E4 and L1 proteins of the β-genotypes, we were able to visualize productive infection in 4 out of 19 actinic keratoses, and in the pathological borders of 1 out of 14 squamous cell carcinomas and 1 out of 31 basal cell carcinomas. Increased expression of the cellular proliferation marker minichromosome maintenance protein 7 (MCM7), that extended into the upper epithelial layers, was a common feature of all the E4-positive areas, indicating that cells were driven into the cell cycle in areas of productive viral infections. Although the present study does not directly demonstrate a causal role of these viruses, the detection of E4 and L1 positivity in actinic keratosis and the adjacent pathological epithelium of skin cancer, clearly shows that β-HPV are actively replicating in the intraepidermal precursor lesions of kidney transplant recipients and can therefore cooperate with other carcinogenic agents, such as UVB, favoring skin cancer promotion.

De novo malignancies following liver transplantation: results from a multicentric study in central and southern Italy, 1990-2008

OBJECTIVE

The objective of this study was to quantify incidence rates (IR) and risks of de novo tumors (except nonmelanoma skin cancers) in patients who underwent orthotopic liver transplantation (OLT) in central and southern Italy.

METHODS

Data were collected on 1675 patients (75.5% males) who underwent OLT in six Italian transplantation centers in central and southern Italy (1990-2008). The time at risk of cancer (person years [PY]) was computed from OLT to the date of cancer diagnosis, death, or last follow-up, whichever occurred first. The number of observed cancer cases were compared with the expected one using data from population-based cancer registries. We computed gender- and age-standardized incidence ratios (SIRs) and 95% confidence intervals (CIs).

RESULTS

During 10,104.3 PYs (median follow-up, 5.2 years), 98 patients (5.9% of the total) were diagnosed with a de novo malignancy (for a total of 100 diagnoses). Twenty-two of these cancers were post-transplantation lymphoproliferative disorders (PTLD; 18 non-Hodgkin lymphoma [NHL] and 2 Hodgkin's lymphoma [HL]), 6 were Kaposi's sarcoma (KS), and 72 were solid tumors (19 head and neck [H&N], 13 lung, 11 colon-rectum, 6 bladder, and 4 melanoma). The overall incidence was 9.9 cases/10(3) PYs, with a 1.4-fold significantly increased SIR (95% CI, l.2-1.7). Significantly increased SIRs were observed for KS (37.3), PTLD (3.9), larynx (5.7), melanoma (3.1), tongue (7.1), and H&N (4.5) cancers.

CONCLUSIONS

These results confirmed that OLT patients are at greater risk for cancer, mainly malignancies either virus-associated or related to pre-existent factors (eg, alcohols). These observations point to the need to improve cancer surveillance after OLT. The on-going enrollment of patients in the present cohort study will help to elucidate the burden of cancer after OLT and better identify risk factors associated with its development.

mTOR inhibitors in pediatric kidney transplantation

The mammalian target of the rapamycin (mTOR) inhibitors sirolimus and everolimus are increasingly being used in pediatric kidney transplantation in different combinations and doses. Several studies have shown beneficial effects of using mTOR inhibitors in children after pediatric renal transplantation. A switch to a low-dose calcineurin inhibitor (CNI) and mTOR inhibitor has been proven to stabilize the glomerular filtration rate. Additionally, de novo studies using a low-dose CNI and an mTOR inhibitor have shown good graft survival and a low number of rejections. Side effects of mTOR inhibitors, such as hyperlipidemia, wound healing problems, and proteinuria, mainly occur if high doses are given and if treatment is not combined with a CNI. Lower doses of mTOR inhibitors do not result in growth impairment or reduced testosterone levels. Treatment with mTOR inhibitors is also associated with a lower number of viral infections, especially cytomegalovirus. Due to their antiproliferative effect, mTOR inhibitors could theoretically reduce the risk of post-transplant lymphoproliferative disease. mTOR inhibitors, especially in combination with low-dose CNIs, can safely be used in children after kidney transplantation as de novo therapy or for conversion from CNI- and mycophenolate mofetil-based regimens.

A prospective study in male recipients of kidney transplantation reveals divergent patterns for inhibin B and testosterone secretions

Background

Male patients with chronic kidney disease often exhibit the biological and clinical hallmarks of an abnormal hypothalamo–pituitary–gonadal axis. It is known that dialysis does not reverse this impaired endocrine status; however, the impact of kidney transplantation (KT) is still controversial. The aim of our study was to investigate the levels of serum gonadotropins, testosterone, and inhibin B during dialysis and after KT.

Methods

A longitudinal and prospective single center study was led in an academic setting. Blood hormones levels were assayed by immunoassays in 53 men (mean age: 37 years) receiving dialysis (T₀) and at 6 months post-KT (T₁₈₀). These data were compared with those from 46 fertile semen donors (mean age: 37 years). The main outcome measure was the between-groups differences in hormones levels. A second criterion was the comparison of T₀ and T₁₈₀ hormones levels according to the immunosuppressive regimen.

Results

For patients ongoing dialysis, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) mean levels were high, whereas testosterone and inhibin B mean levels remained normal. After KT, LH levels returned to normal whereas FSH was significantly increased. Testosterone levels remained normal whereas inhibin B levels significantly decreased. We found that the combination tacrolimus plus mycophenolic acid significantly decreased post-KT inhibin B levels. Moreover, we found that pre-graft inhibin-B level was independent of testosterone and could predict low post-operative inhibin B level with a sensitivity of 77% and a specificity of 92%.

Conclusions

Our study suggests that endocrine secretions of Leydig and Sertoli cells are differently impacted by dialysis, KT and immunosuppressive regimen raising new issues to explore.

mTOR inhibitors and renal allograft: Yin and Yang

Mammalian target of rapamycin inhibitors (mTOR-I), everolimus and sirolimus, are immunosuppressive drugs extensively used in renal transplantation. Their main mechanism of action is the inhibition of cell signaling through the PI3 K/Akt/mTOR pathway. This interesting mechanism of action confers to these medications both great immunosuppressive potential and important anti-neoplastic properties. Although the clinical utility of this drug category, as with other antineoplastic/immunosuppressants, is clear, the use of mTOR-I commonly results in the development of several complications. In particular, these agents may determine severe renal toxicity that, as recent studies report, seems clearly correlated to dose and duration of drug use. The mTOR-I-induced renal allograft spectrum of toxicity includes the enhanced incidence of delayed graft function, nephrotoxicity in particular when co-administered with calcineurin inhibitors (CNI) and onset of proteinuria. The latter effect appears highly frequent in patients undergoing mTOR-I treatment and significantly associated with a rapid graft lost. The damage leading to this complication interests both the glomerular and tubular area. mTOR-I cause an inhibition of proliferation in podocytes and the epithelial-to-mesenchymal transition in tubular cells. Interestingly, all these side effects are mostly reversible and dose related. Therefore, it is unquestionable that these particular drugs should be administered at the lowest dose able to maintain relatively low trough levels, in order to maximize their important and specific therapeutic effects while minimizing or avoiding drug toxicities. Utilization of low dosages of mTOR-I should be encouraged not only in CNI-combined schemas, but also when administered alone in a CNI-free immunosuppressive protocol.

[The management of lung transplantation candidates. A case series]

INTRODUCTION

Lung transplantation (LT) is associated with an increased risk of infection, cancer, chronic renal failure, cardiovascular disease and osteoporosis. Some risk factors precede transplantation and could benefit for early diagnosis and optimised care.

METHODS

The incidence of comorbidities and their treatment before referral were assessed in 157 consecutive lung transplant candidates between 2008 and 2011.

RESULTS

The median age was 37years [25; 51]. Fifty-six percent had a body mass index below 19kg/m(2). In the COPD group, only 50 % had undergone a pulmonary rehabilitation program in the preceding 2 years. Osteoporosis was present in 42 %, of whom 36 % were on bisphophonate therapy. Vitamin D deficiency was present in 65 %. Previously undiagnosed cardiovascular risk factors were discovered during LT assessment: hypertension in one patient, hypercholesterolemia in 6 % and diabetes in 4 %. Poor dental condition necessitating extractions were found in 41 % of patients. Protective anti-HBs antibodies levels were present in 50 % of the patients at the time of referral.

CONCLUSION

The assessment and early treatment of nutritional disorders, osteoporosis and risk factors for infection as well as addressing associated cardiovascular risk factors should be optimised in the care of patients with chronic respiratory insufficiency. The potential for becoming a lung transplant candidate in the future should be kept in mind early in the global management of those patients.

Checking whether there is an increased risk of post-transplant lymphoproliferative disorder and other cancers with specific modern immunosuppression regimens in renal transplantation: protocol for a network meta-analysis of randomized and observational studies

BACKGROUND

Patients undergoing renal transplant procedures require multi-agent immunosuppressive regimens both short term (induction phase) and long term (maintenance phase) to minimize the risk of organ rejection. There are several drug classes and agents for immunosuppression. Use of these agents may increase the risk of different harms including not only infections, but also malignancies including post-transplant lymphoproliferative disorder. There is a need to identify which regimens minimize the risk of such outcomes. The objective of this systematic review and network meta-analysis of randomized and observational studies is to explore whether certain modern regimens of immunosuppression used to prevent organ rejection in renal transplant patients are associated with an increased risk of post-transplant lymphoproliferative disorder and other malignancies.

METHODS/DESIGN

'Modern' regimens were defined to be those evaluated in controlled studies beginning in 1990 or later. An electronic literature search of Medline, Embase and the Cochrane Central Register of Controlled Trials has been designed by an experienced information specialist and peer reviewed by a second information specialist. Study selection and data collection will be performed by two reviewers. The outcomes of interest will include post-transplant lymphoproliferative disorder and other incident forms of malignancy occurring in adult renal transplant patients. Network meta-analyses of data from randomized and observational studies will be performed where judged appropriate based on a review of the clinical and methodological features of included studies. A sequential approach to meta-analysis will be used to combine data from different designs.

DISCUSSION

Our systematic review will include both single-agent and multi-agent modern pharmacotherapy regimens in patients undergoing renal transplantation. It will synthesize malignancy outcomes. Our work will also add to the development of methods for network meta-analysis across study designs to assess treatment safety.

TRIAL REGISTRATION

PROSPERO Registration Number: CRD42013006951.

Radical retropubic and perineal prostatectomy for clinically localised prostate cancer in renal transplant recipients

Objective

To analyse the functional and oncological outcome of consecutive renal-transplant recipients (RTRs) with clinically localised prostate cancer who underwent radical retropubic (RRP) or perineal (RPP) prostatectomy.

Patients and methods

Between January 2000 and July 2011 16 patients underwent RRP (group 1) and seven RPP (group 2). In all, 200 consecutive non-RTRs served as the control group, of whom 100 each underwent RRP and RPP, respectively. The mean (range) interval between renal transplantation and RP was 95 (24–206) months, the PSA at the time of diagnosis was 4.5 (3.0–17.5) ng/mL, and the mean patient age was 64 (59–67) years.

Results

The mean follow-up was 39 (RRP) and 48 months (RPP). There was no deterioration in graft function. In group 1, 13 and three patients had pT2a-cpN0 and pT3a-bpN0 prostate cancer, respectively, with a Gleason score of 6, 7 and 8 in 11, three and one patients, respectively. In group 2, three and four patients had pT2a-c and pT3a-b disease, respectively, with a Gleason score of 6 and 7 in two and five, respectively. In both groups one patient had a positive surgical margin and was followed expectantly, and all patients have no evidence of disease. Wound infections developed more often in the RPP group (29% vs. 7%), but there were no Clavien grade III–V complications. All patients achieved good continence, and two need one pad/day.

Conclusions

RRP and RPP are suitable surgical treatments for prostate cancer in RTRs. RRP might be preferable, as it has the advantage of simultaneous pelvic lymphadenectomy and a lower risk of infectious complications.

Clinical and pathological outcomes of renal cell carcinoma (RCC) in native kidneys of patients with end-stage renal disease: a long-term comparative retrospective study with RCC diagnosed in the general population

PURPOSE

Patients with end-stage renal disease (ESRD) have an increased risk of developing renal cell carcinoma (RCC). This retrospective study compared clinical and pathological outcomes of RCC occurring in native kidneys of patients with ESRD (whether they underwent kidney transplantation or not) with those of renal tumors diagnosed in the general population.

METHODS

The study included a total of 533 patients with RCC. The ESRD cohort included 92 patients with RCC in native kidneys. Of these, 58 and 34 cases were identified before (pre-Tx group) and after kidney transplantation (post-Tx group), respectively. The control group was composed of 441 RCCs diagnosed in the general population. Variables were compared by chi-square and Student's t tests. Cancer-specific survival was assessed by Kaplan-Meier and Cox methods.

RESULTS

The ESRD groups had smaller (P = 0.001), lower-grade, and lower-stage tumors than the non-ESRD group (P = 0.001). The papillary RCC rate was higher in the ESRD groups (P = 0.01). Ten-year cancer-specific survivals were 94.5, 87.9, and 74.6 % in pre-Tx, post-Tx, and non-ESRD patients, respectively (P = 0.003). Mean follow-up was 90.2 months. At multivariate analysis, tumor size (HR = 1.10), pathological stage (HR = 1.46), presence of nodal (HR = 2.22) and visceral metastases (HR = 3.49), and Fuhrman grade (HR = 1.48) were independent adverse prognostic factors for cancer-specific survival.

CONCLUSIONS

Native kidney RCCs arising in ESRD patients are lower stage and lower grade as compared to RCCs diagnosed in the general population, and these tumors exhibit favorable clinical and outcome features.

Risk of bladder cancer in renal transplant recipients: a meta-analysis

Background:

Renal transplantation has been associated with a significantly increased risk of developing cancers during long-term follow-up, but for bladder cancer, this risk is less clear. We therefore performed a meta-analysis to determine whether bladder cancer risk in renal transplant recipients was increased.

Methods:

Eligible studies were identified through searches of PubMed and other public resources. Random-effects meta-analyses were used to pool overall estimates for standardised incidence ratios (SIRs). Heterogeneity test, sensitivity analysis, and assessment of publishing bias were also performed.

Results:

We identified a 3.18-fold higher SIR (95% confidence intervals (CI): 1.34–7.53, P=0.008) of bladder cancer in patients following renal transplantation compared with the general population, based on data from 79 988 patients with a total follow-up of 308 458 patient-years. When stratified by ethnicity, the SIRs for bladder cancer were 2.00 (95% CI: 1.51–2.65, P=0.001) and 14.74 (95% CI: 3.66–59.35, P<0.001) between European and Asian renal transplant recipients, respectively.

Conclusions:

Our study demonstrated that the risk of developing bladder cancer in transplant populations was increased. Such association suggests that physicians should be more vigilant in checking for bladder cancer in transplantation recipient population.

Solid tumors following kidney transplantation in children

Kidney transplant recipients have an increased risk of cancer. Data on non-LPD malignancies (solid tumors) in pediatric renal transplant recipients are limited. We performed a cohort study using the NAPRTCS transplant registry to describe the incidence of non-LPD malignancy compared with the general pediatric population. The observed incidence rate of non-LPD malignancy in the NAPRTCS transplant registry was 72.1 per 100,000 person-years (SIR 6.7; 95% CI, 5.3, 8.5); a 6.7-fold increased risk compared with the general pediatric population (10.7 cases per 100,000 person-years). Non-LPD malignancy was diagnosed in 35 subjects at a median of 726 days post-transplant. The most common type of malignancy was renal cell carcinoma. The increased risk of non-LPD malignancy was seen in all patients regardless of age, gender, race, etiology of end-stage kidney disease, and transplant era. The specific type of immunosuppression was not identified as a risk factor. In this first large-scale study of North American pediatric renal transplant recipients, we observed a 6.7-fold increased risk of non-LPD malignancy compared with the general pediatric population. Further examination of this unique patient population may provide greater insight into the impact of transplant and immunosuppression on malignancy risk.

eRapa restores a normal life span in a FAP mouse model

Mutation of a single copy of the adenomatous polyposis coli (APC) gene results in familial adenomatous polyposis (FAP), which confers an extremely high risk for colon cancer. Apc(Min/+) mice exhibit multiple intestinal neoplasia (MIN) that causes anemia and death from bleeding by 6 months. Mechanistic target of rapamycin complex 1 (mTORC1) inhibitors were shown to improve Apc(Min/+) mouse survival when administered by oral gavage or added directly to the chow, but these mice still died from neoplasia well short of a natural life span. The National Institute of Aging Intervention Testing Program showed that enterically targeted rapamycin (eRapa) extended life span for wild-type genetically heterogeneous mice in part by inhibiting age-associated cancer. We hypothesized that eRapa would be effective in preventing neoplasia and extend survival of Apc(Min/+) mice. We show that eRapa improved survival of Apc(Min/+) mice in a dose-dependent manner. Remarkably, and in contrast to previous reports, most of the Apc(Min/+) mice fed 42 parts per million eRapa lived beyond the median life span reported for wild-type syngeneic mice. Furthermore, chronic eRapa did not cause detrimental immune effects in mouse models of cancer, infection, or autoimmunity, thus assuaging concerns that chronic rapamycin treatment suppresses immunity. Our studies suggest that a novel formulation (enteric targeting) of a well-known and widely used drug (rapamycin) can dramatically improve its efficacy in targeted settings. eRapa or other mTORC1 inhibitors could serve as effective cancer preventatives for people with FAP without suppressing the immune system, thus reducing the dependency on surgery as standard therapy.

Tumor necrosis factor receptor 2: its contribution to acute cellular rejection and clear cell renal carcinoma

Tumor necrosis factor receptor 2 (TNFR2) is a type I transmembrane glycoprotein and one of the two receptors that orchestrate the complex biological functions of tumor necrosis factor (TNF, also designed TNF-α). Accumulating experimental evidence suggests that TNFR2 plays an important role in renal disorders associated with acute cellular rejection and clear cell renal carcinoma but its exact role in these settings is still not completely understood. This papers reviews the factors that may mediate TNFR2 induction in acute cellular rejection and clear cell renal carcinoma and its contribution to these conditions and discusses its therapeutic implications. A greater understanding of the function of TNFR2 may lead to the development of new anti-TNF drugs.

Growing experience with mTOR inhibitors in pediatric solid organ transplantation

Controlled trials of mTOR inhibitors in children following solid organ transplantation are scarce, although evidence from prospective single-arm studies is growing. Everolimus with reduced CNI therapy has been shown to be efficacious and safe in de novo pediatric kidney transplant patients in prospective trials. Prospective and retrospective data in children converted from CNI therapy to mTOR inhibition following kidney, liver, or heart transplantation suggest preservation of immunosuppressive efficacy. Good renal function has been maintained when mTOR inhibitors are used de novo in children following kidney transplantation or after conversion to mTOR inhibition with CNI minimization. mTOR inhibition with reduced CNI exposure is associated with a low risk for developing infection in children. Growth and development do not appear to be impaired during low-dose mTOR inhibition, but more studies are required. No firm conclusions can be drawn as to whether mTOR inhibitors should be discontinued in children requiring surgical intervention or whether mTOR inhibition delays progression of hepatic fibrosis after pediatric liver transplantation. In conclusion, current evidence suggests that use of mTOR inhibitors in children undergoing solid organ transplantation is efficacious and safe, but a number of issues remain unresolved and further studies are required.

Ambulatory arterial stiffness index in children after kidney transplantation

Given the increase in CV morbidity after RTx and the scarcity of CV events in pediatrics, surrogate markers should be assessed to characterize CV damage in this population. AASI is a marker of arterial stiffness in adults, predicting cardio- and cerebrovascular morbidity. Our aim was to assess the determinants of AASI in RTx children (n = 54, 15.5 ± 3.5 yr) and to examine its relationship to central PWV. AASI was calculated from 24 h ABPM. PWV was determined by applanation tonometry, body composition by multifrequency bioimpedance measurement. The dipping state, volume overload, and time on dialysis were the main predictors of AASI (p < 0.05). Children with established HT (n = 34) had increased AASI, extracellular body water, and BNP (p < 0.05). In contrast to AASI, PWV did not differ between HT and normotensive RTx patient groups. There was no correlation between AASI and PWV. PWV was increased in children who spent more than one yr on dialysis prior to RTx. In conclusion, increased AASI in HT RTx children better characterizes the actual volume- and pressure-dependent arterial rigidity rather than long-term morphological changes in large arteries as reflected by PWV.

Systemic and nonrenal adverse effects occurring in renal transplant patients treated with mTOR inhibitors

The mammalian target of rapamycin inhibitors (mTOR-I), sirolimus and everolimus, are immunosuppressive drugs largely used in renal transplantation. The main mechanism of action of these drugs is the inhibition of the mammalian target of rapamycin (mTOR), a regulatory protein kinase involved in lymphocyte proliferation. Additionally, the inhibition of the crosstalk among mTORC1, mTORC2, and PI3K confers the antineoplastic activities of these drugs. Because of their specific pharmacological characteristics and their relative lack of nephrotoxicity, these inhibitors are valid option to calcineurine inhibitors (CNIs) for maintenance immunosuppression in renal transplant recipients with chronic allograft nephropathy. However, as other immunosuppressive drugs, mTOR-I may induce the development of several adverse effects that need to be early recognized and treated to avoid severe illness in renal transplant patients. In particular, mTOR-I may induce systemic nonnephrological side effects including pulmonary toxicity, hematological disorders, dysmetabolism, lymphedema, stomatitis, cutaneous adverse effects, and fertility/gonadic toxicity. Although most of the adverse effects are dose related, it is extremely important for clinicians to early recognize them in order to reduce dosage or discontinue mTOR-I treatment avoiding the onset and development of severe clinical complications.