Managing cancer risk and decision making after kidney transplantation

Incidence, Risk Factors, and Outcomes of De Novo Malignancy following Kidney Transplantation

Introduction: Post-transplant malignancy is a significant cause of morbidity and mortality following kidney transplantation often emerging after medium- to long-term follow-up. To understand the risk factors for the development of de novo post-transplant malignancy (DPTM), this study aimed to assess the incidence, risk factors, and outcomes of DPTM at a single nephrology centre over two decades. Methods: This retrospective cohort study included 963 kidney transplant recipients who underwent kidney transplantation between January 2000 and December 2020 and followed up over a median follow-up of 7.1 years (IQR 3.9-11.4). Cox regression models were used to identify the significant risk factors of DPTM development, the association of DPTM with graft survival, and mortality with a functioning graft. Results: In total, 8.1% of transplant recipients developed DPTM, and the DPTM incidence rate was 14.7 per 100 patient-years. There was a higher mean age observed in the DPTM group (53 vs. 47 years, p < 0.001). The most affected organ systems were genitourinary (32.1%), gastrointestinal (24.4%), and lymphoproliferative (20.5%). Multivariate Cox analysis identified older age at transplant (aHR 9.51, 95%CI: 2.60-34.87, p < 0.001) and pre-existing glomerulonephritis (aHR 3.27, 95%CI: 1.10-9.77, p = 0.03) as significant risk factors for DPTM. Older age was significantly associated with poorer graft survival (aHR 8.71, 95%CI: 3.77-20.20, p < 0.001). When age was excluded from the multivariate Cox model, DPTM emerged as a significant risk factor for poor survival (aHR 1.76, 95%CI: 1.17-2.63, p = 0.006). Conclusion: These findings underscore the need for tailored screening, prevention, and management strategies to address DPTM in an aging and immunosuppressed kidney transplant population.

Patient preferences for cancer screening in chronic kidney disease: a best-worst scaling survey

BACKGROUND

Despite an increased cancer risk for patients with chronic kidney disease (CKD), uptake of cancer screening varies due to competing priorities and complex health-related issues. This study aimed to elicit the preferences and important attributes of cancer screening in patients with CKD.

METHODS

An on-line best-worst scaling survey was used to ascertain the relative importance of 22 screening attributes among CKD patients using an incomplete block design. Preference scores (0-1) were calculated by multinomial logistic regression. Preference heterogeneity was evaluated.

RESULTS

The survey was completed by 83 patients: 26 not requiring kidney replacement therapy, 20 receiving dialysis and 37 transplant recipients (mean age 59 years, 53% men, 75% prior to cancer screening). The five most important attributes were early detection {preference score 1.0 [95% confidence interval (CI) 0.90-1.10]}, decreased risk of cancer death [0.85 (0.75-0.94)], false negatives [0.71 (0.61-0.80)], reduction in immunosuppression if detected [0.68 (0.59-0.78)] and non-invasive interventions after positive results [0.68 (0.59-0.78)]. Preference heterogeneity reflected the stage of CKD. Immunosuppression reduction [mean difference 0.11 (95% CI 0.02-0.19)] and views of family/friends [0.10 (reference attribute)] were important for transplant recipients. Screening frequency [-0.18 (95% CI -0.26 to -0.10)] and overdiagnosis of harmless cancers [-0.14 (95% CI -0.22 to -0.10)] were important for dialysis patients.

CONCLUSION

Early detection, risk of cancer-related death, false negatives, immunosuppression reduction and non-invasive interventions following detection are important cancer screening considerations among CKD patients. Patient preferences are key to shared decision-making and individualized cancer screening.

Post‐kidney transplant cancers: Racial and ethnic differences in sun‐exposed skin versus non‐sun‐exposed anogenital skin

BACKGROUND

Transplant recipients have a 2- to 4-fold increased risk of developing malignancies over the general population. Cancer is the second most common cause of death for recipients. The magnitude of the risk depends on the cancer type and increases in viral-related malignancies. Skin cancer is the most common. However, data in most cancer registries is limited to cutaneous melanomas, thereby limiting the epidemiologic examination of cancer risk in non-melanoma skin cancer. Our goal was to evaluate post-kidney transplant cancer cases and sites in our population to guide screening recommendations.

METHODS

Between 2009 and 2015, a retrospective study of adult kidney recipients transplanted at East Carolina University was conducted. The first cancer diagnosis after transplant through February 18, 2020, was captured and analyzed. Patient demographics, cancer sites, and histological diagnoses were analyzed and compared. p16 immunohistochemistry was used as a surrogate marker for high-risk human papillomavirus (HPV) infection.

RESULTS

Retrospectively, kidney transplant recipients were analyzed (N = 439), the majority were non-Hispanic Black (NHB) individuals, 312 (71.1%), and 127 (28.9%) were non-Hispanic White (NHW) individuals. Of these, 59 (13.4%) developed a posttransplant malignancy, with the majority on sun-exposed skin found in NHW. NHB had all anogenital/mucosa skin cancers on non-sun-exposed skin. Of these detected in NHB, all were squamous cell carcinomas, with five out of six (83.3%) being positive for p16.

CONCLUSIONS

Posttransplant malignancy differed significantly by race, site, and potential source of etiology. The majority of malignancies are likely explained by acceleration of precursor lesions from prior exposure to ultraviolet rays or HPV.

De Novo Malignancies after Kidney Transplantation

Cancer is an important outcome after kidney transplantation because it is the second leading cause of death in most Western countries. The excess risk of cancer after transplantation is approximately two to three times higher than the age- and sex-matched general population, driven largely by viral- and immune-related cancers. Once cancer develops, outcomes are generally poor, particularly for those with melanoma, renal cell carcinoma, and post-transplant lymphoproliferative disease. More importantly, effective screening and treatment strategies are limited in this high-risk population. In this review, we begin with a patient's journey that maps the experience of living with a kidney transplant and understand the patient's knowledge, education, and experience of cancer in the context of transplantation. The epidemiology and burden of cancer in recipients of kidney transplants, along with the up-to-date screening and treatment strategies, are discussed. We also focus on the current understanding of optimal care for recipients of kidney transplants who are living with cancer from the patients' perspectives.

Risk factors and incidence of malignant neoplasms after kidney transplantation at a single institution in Japan

BACKGROUND

The risk of malignant neoplasms increases in kidney transplantation (KT) recipients (KTRs). However, Japanese registry studies have not been reported since 2000.

METHODS

We retrospectively reviewed the medical records of 346 patients who underwent KT at Gifu University Hospital, Japan since 2000. Patients were divided into two groups based on whether they developed malignancy after KT or not. The incidence, type of malignancy, risk factors, and prognosis for malignancy were examined.

RESULTS

In this study, 22 de novo malignant neoplasms were identified in 20 KTRs (7.3%), with a median follow-up period of 8.2 years. Cumulative incidence of any malignant neoplasms was 1.1% within 1 year and 4.4% within 5 years. The 5-year overall survival (OS) rates were 71.8% in KTRs with malignant neoplasms and 98.6% in KTRs without malignant neoplasms. Uni- and multivariate analysis revealed that age at KT and acute rejection (AR) episode were significant predictors for incidence of malignancy.

CONCLUSIONS

The development of malignant neoplasms was associated with poor OS and graft survival. We consider that appropriate screening and investigation of symptoms are important for KTRs, particularly for older KTRs at transplantation and those with AR episode.

Immunotherapy in breast cancer

The idea of using the immune system to fight cancer is over 100 years old. A new molecular approach led to a better understanding of the immune system. Checkpoint regulation, understanding the roles of Tregs, Th1, and Th2, development of Chimeric antigen receptor (CAR)-T cells, as well as regulation of dendritic cells and macrophages, are just a few examples of our understating that has also led to the discovery of immune checkpoint inhibitors (ICIs) and modulators. This led the Nobel Prize committee in 2018, to award Dr. James P. Allison the Nobel Prize in medicine for the discovery of Cytotoxic T-lymphocyte-associated antigen-4, and Dr. Tasuku Honjo for the discovery of programmed cell death-1 (PD-1)/PD-1-ligand (PDL-1). Several ICIs are already approved by the regulatory authorities, and many more are currently used in studies of several solid tumors and hematologic malignancies. Positive studies have led to the US Food and Drug Administration (FDA) and European Medicines Agency approval of a number of these compounds, but none to date are approved in breast cancer (BC). Moreover, PD-1/PDL-1, MSI high (and dMMR), and tumor mutational burden are the currently “best” predictive markers for benefit from immunotherapy. BCs have some of these markers positive only in subsets but less frequently expressed than most other solid tumors, for example, malignant melanoma or non-small cell lung cancer. To improve the potential efficacy of ICI in BC, the addition of chemotherapy was one of the strategies. Many early and large clinical trials in all phases are underway in BC. We will discuss the role of immune system in BC editing, and the potential impact of immunotherapy in BC outcomes.

Gender differences in cancer risk after kidney transplantation

Kidney transplant (KT) recipients are at greater risk of developing some cancers than the general population. Moreover, cancer is the only cause of death that is currently increasing after kidney transplantation. We analyzed incidence, risk factors and characteristics of post-transplant malignancies (solid organ tumors and lymphoproliferative disorders) at our center in 925 KT recipients (1979-2014). Sex differences were particularly assessed. One hundred and eight patients (11.7%) developed solid organ tumors (76.9%) or lymphoma (23.1%). Twenty-one percent of patients who reached 20 years after KT developed cancer, with a median post-KT time to diagnosis of 7.4 years. Most common solid organs affected were lung (30.1%), prostate (10.8%), bladder (9.6%), and native kidney (7.2%). When analyzing standardized incidence ratios (SIR) by gender compared to the general population, relative risk was increased in women (SIR = 1.81; 95%CI, 1.28-2.45) but not significantly increased in men (SIR = 1.22; 0.95-2.52). Regarding specific types, gynecological (SIR = 11.6; 4.2-22.7) and lung (SIR = 10.0; 4.3-18.2) in women, and bladder (SIR = 16.3; 5.9-32.1) in men were the most affected locations. Thymoglobulin, a polyclonal antibody that has been used as an immunosuppressive agent in kidney transplantation over the last decades, was a significant risk factor for developing cancer in adjusted regression analysis [IRR = 1.62, 1.02-2.57; p = 0.041], and was associated with lower patient survival. Compared with the general population, the incidence of post-KT non-skin cancer is almost two-fold higher in women but not significantly higher in men. Lung is the most common solid organ affected. Thymoglobulin induction therapy is associated with a greater risk.

One-Time Fecal Immunochemical Screening for Advanced Colorectal Neoplasia in Patients with CKD (DETECT Study)

BACKGROUND

In patients with CKD, the risk of developing colorectal cancer is high and outcomes are poor. Screening using fecal immunochemical testing (FIT) is effective in reducing mortality from colorectal cancer, but performance characteristics of FIT in CKD are unknown.

METHODS

To determine the detection rates and performance characteristics of FIT for advanced colorectal neoplasia (ACN) in patients with CKD, we used FIT to prospectively screen patients aged 35-74 years with CKD (stages 3-5 CKD, dialysis, and renal transplant) from 11 sites in Australia, New Zealand, Canada, and Spain. All participants received clinical follow-up at 2 years. We used a two-step reference standard approach to estimate disease status.

RESULTS

Overall, 369 out of 1706 patients who completed FIT (21.6%) tested positive; 323 (87.5%) underwent colonoscopies. A total of 1553 (91.0%) completed follow-up; 82 (4.8%) had died and 71 (4.2%) were lost. The detection rate of ACN using FIT was 6.0% (5.6%, 7.4%, and 5.6% for stages 3-5 CKD, dialysis, and transplant). Sensitivity, specificity, and positive and negative predictive values of FIT for ACN were 0.90, 0.83, 0.30, and 0.99, respectively. Of participants who underwent colonoscopy, five (1.5%) experienced major colonoscopy-related complications, including bowel perforation and major bleeding.

CONCLUSIONS

FIT appears to be an accurate screening test for patients with CKD, such that a negative test may rule out the diagnosis of colorectal cancer within 2 years. However, the risk of major complications from work-up colonoscopy are at least ten-fold higher than in the general population.

Cancer risk after renal transplantation in South Korea: a nationwide population-based study

Background

This study aimed to evaluate patterns of posttransplant malignancies among renal transplant recipients (RTRs) in South Korea using nationwide data.

Methods

The nationwide cohort assessed in this study included RTRs from January 1, 2010, to December 31, 2014. We analyzed cancer incidence during the time course after renal transplantation. Additionally, we calculated standardized incidence ratios (SIRs) to evaluate the risk of malignancies in RTRs.

Results

A total of 1343 RTRs (871 males and 472 females, mean age 48.5 ± 11.6 years) were assessed. Among them, 104 (7.7%) developed malignancies after transplantation, most commonly in the thyroid cancer (23.1%). The SIR for all cancers was 3.54; particularly, the SIRs for renal cancer, myeloma, and non-Hodgkin lymphoma were 16.31, 24.02, and 28.64, respectively. Females showed a higher risk of malignancy than males (SIRs: 4.04 for women and 3.26 for men). The median interval between transplantation and malignancy diagnosis was 27.2 months (range 12.3–54.8 months).

Conclusions

RTRs in South Korea demonstrated a high risk of malignancy after transplantation compared with the general population. This indicates that close surveillance and routine screening for cancer in RTRs are needed.

Urologic malignancies in kidney transplantation

With advances in immunosuppression, graft and patient outcomes after kidney transplantation have improved considerably. As a result, long-term complications of transplantation, such as urologic malignancies, have become increasingly important. Kidney transplant recipients, for example, have a 7-fold risk of renal cell carcinoma (RCC) and 3-fold risk of urothelial carcinoma (UC) compared with the general population. While extrapolation of data from the general population suggest that routine cancer screening in transplant recipients would allow for earlier diagnosis and management of these potentially lethal malignancies, currently there is no consensus for posttransplantation RCC or UC screening as supporting data are limited. Further understanding of risk factors, presentation, optimal management of, and screening for urologic malignancies in kidney transplant patients is warranted, and as such, this review will focus on the incidence, surveillance, and treatment of urologic malignancies in kidney transplant recipients.

[Focusing on kidney transplantation in the elderly]

Due to the increase in life expectancy and the ageing of end-stage renal disease patients, the number of patients older than 65 years receiving a kidney transplant has been continuously growing over the last fifteen years. The benefits of renal transplantation compared to dialysis in terms of survival and quality of life have been shown in selected recipients over 65, or 70 years. However, the age remains the main limiting factor for the access to the waiting list, and the reluctance of the clinicians can be explained by the multiple comorbidities of these candidates, their limited life expectancy or the shortage of grafts. The challenge is to select the candidates who can benefit from renal transplantation, thanks to rigorous cardiovascular and neoplastic evaluation before enrolment and by taking into account the specific characteristics of elderly patients. The living donor appears to be the ideal option for elderly recipients, the alternative being the extended criteria donor, allowing waiting times to be limited. The choice of immunosuppressive therapy is also crucial in these patients at high risk of infectious and cardiovascular complications in whom the occurrence of acute rejection can have severe consequences. There are currently no specific recommendations for immunosuppression in elderly recipients, and we would need large-scale randomized studies to improve the prognosis of renal transplantation in this population.

Association of Pretransplant Skin Cancer With Posttransplant Malignancy, Graft Failure and Death in Kidney Transplant Recipients

BACKGROUND

Posttransplant malignancy (PTM) is one of the leading causes of late death in kidney recipients. Those with a cancer history may be more prone to develop a recurrent or a new cancer. We studied the association between pretransplant skin cancer, PTM, death, and graft failure.

METHODS

Primary adult kidney recipients transplanted between 2005 and 2013 were included. Malignancy information was obtained from Organ Procurement Kidney Transplant Network/United Network for Organ Sharing registration and follow-up forms. Posttransplant malignancy was classified into skin cancer, solid tumor, and posttransplant lymphoproliferative disorder (PTLD). Competing risk and survival analysis with adjustment for confounders were used to calculate risk for PTM, death and graft failure in recipients with pretransplant skin cancer compared with those without cancer. Risk was reported in hazard ratios (HR) with 95% confidence interval (CI).

RESULTS

The cohort included 1671 recipients with and 102 961 without pretransplant skin malignancy. The 5-year cumulative incidence of PTM in patients with and without a pretransplant skin cancer history was 31.6% and 7.4%, respectively (P < 0.001). Recipients with pretransplant skin cancer had increased risk of PTM (sub-HR [SHR], 2.60; 95% CI, 2.27-2.98), and posttransplant skin cancer (SHR, 2.92; 95% CI, 2.52-3.39), PTLD (SHR, 1.93; 95% CI, 1.01-3.66), solid tumor (SHR, 1.44; 95% CI, 1.04-1.99), death (HR, 1.20; 95% CI, 1.07-1.34), and graft failure (HR, 1.17; 95% CI, 1.05-1.30) when compared with those without pretransplant malignancy.

CONCLUSIONS

Pretransplant skin cancer was associated with an increased risk of posttransplant skin cancer, PTLD, solid organ cancer, death and graft failure.

Daunting but Worthy Goal: Reducing the De Novo Cancer Incidence After Transplantation

Solid-organ transplant recipients are at increased risk of developing de novo malignancies compared with the general population, and malignancies become a major limitation in achieving optimal outcomes. The prevention and the management of posttransplant malignancies must be considered as a main goal in our transplant programs. For these patients, immunosuppression plays a major role in oncogenesis by both impairement of immunosurveillance, enhancement of chronic viral infection, and by direct prooncogenic effects. It is essential to manage the recipient with a long-term adapted screening program beginning before transplantation to use a prophylaxis to decrease infection-related cancer, to propose a viral monitoring, and to modulate the immunosuppression toward lower doses especially for calcineurin inhibitors. Indeed, strategies to induce tolerance or to allow a dramatic reduction of the immunosuppression burden are the more promising approaches for the reduction of the posttransplant malignancies.

Cancer Screening Recommendations for Solid Organ Transplant Recipients: A Systematic Review of Clinical Practice Guidelines

Solid organ transplant recipients (SOTRs) are at increased risk of developing and dying from cancer. However, controversies exist around cancer screening in this population owing to reduced life expectancy and competing causes of death. This systematic review assesses the availability, quality and consistency of cancer screening recommendations in clinical practice guidelines (CPGs). We systematically searched bibliographic databases and gray literature to identify CPGs and assessed their quality using AGREE II. Recommendations were extracted along with their supporting evidence. Thirteen guidelines were included in the review. CPGs for kidney recipients were the most frequent source of screening recommendations, and recommendations for skin cancer screening were most frequently presented. Some screening recommendations differed from those for the general population, based on literature demonstrating higher cancer incidence among SOTRs versus direct evidence of screening effectiveness. Relevant stakeholders such as oncology specialists, primary care providers and public health experts were not involved in the formulation of the screening recommendations. In conclusion, although several guidelines make recommendations for cancer screening in SOTRs, the availability of cancer screening recommendations varied considerably by transplanted organ. More studies are required to inform cancer screening recommendations in SOTRs, and guideline development should involve transplant patients, oncologists and cancer screening specialists.

[Chronic kidney disease and kidney transplantation]

OBJECTIVES

To report epidemiology and characteristics of end-stage renal disease (ESRD) patients and renal transplant candidates, and to evaluate access to waiting list and results of renal transplantation.

MATERIAL AND METHODS

An exhaustive systematic review of the scientific literature was performed in the Medline database (http://www.ncbi.nlm.nih.gov) and Embase (http://www.embase.com) using different associations of the following keywords: "chronic kidney disease, epidemiology, kidney transplantation, cost, survival, graft, brain death, cardiac arrest, access, allocation". French legal documents have been reviewed using the government portal (http://www.legifrance.gouv.fr). Articles were selected according to methods, language of publication and relevance. The reference lists were used to identify additional historical studies of interest. Both prospective and retrospective series, in French and English, as well as review articles and recommendations were selected. In addition, French national transplant and health agencies (http://www.agence-biomedecine.fr and http://www.has-sante.fr) databases were screened using identical keywords. A total of 3234 articles, 6 official reports and 3 newspaper articles were identified; after careful selection 99 publications were eligible for our review.

RESULTS

The increasing prevalence of chronic kidney disease (CKD) leads to worsen organ shortage. Renal transplantation remains the best treatment option for ESRD, providing recipients with an increased survival and quality of life, at lower costs than other renal replacement therapies. The never-ending lengthening of the waiting list raises issues regarding treatment strategies and candidates' selection, and underlines the limits of organ sharing without additional source of kidneys available for transplantation.

CONCLUSION

Allocation policies aim to reduce medical or geographical disparities regarding enrollment on a waiting list or access to an allotransplant.

The benefits of cancer screening in kidney transplant recipients: a single-center experience

The frequency of malignancy is increasing in kidney transplant recipients. Posttransplant malignancy (PTM) is a major cause of long-term graft survival inhibition. In this study, we evaluated the frequency and prognosis of PTM at our center and examined the efficacy of cancer screening. Between 1972 and 2013, 750 patients were followed-up at our center. Annual physical examinations and screenings were performed to detect PTM. We investigated the detail of two distinctive cancer groups: screening-detected cancers and symptom-detected cancers. Seventy-seven PTM were identified during the follow-up period. The mean age at the initial PTM detection was 43.6 ± 12.8 years. The mean interval from transplantation to cancer diagnosis was 134.5 ± 11.3 months. Among the 77 patients, posttransplant lymphoproliferative disease (PTLD) was the most common cancer (19.5%, 15/77), followed by renal cell carcinoma (15.6%, 12/77). Of the cancer cases, 46.8% (36/77) were detected via screening. The most frequently screening-detected cancer was renal cell carcinoma of the native kidney and breast cancer (22.2%, 8/36). However, it was difficult to detect PTLD, urothelial carcinoma, and colorectal cancer via screening. Interestingly, Cox proportional regression analyses revealed nonscreened recipients to be a significant prognostic factor for PTM (P < 0.001). This study is the first to report that appropriate screening tests play a key role in early PTM diagnosis and lead to reduce the mortality rate in kidney transplant recipients. These findings support the provision of long-term appropriate screening for kidney transplant recipients.

Post-transplantation malignancies: here today, gone tomorrow?

From the early days of transplantation onwards, increased cancer development in transplant recipients, who require immunosuppression to avoid graft rejection, has been recognized. Registry data indicate that approximately 10-30% of deaths are attributed to post-transplant malignancy, with an upward trend in this incidence as more patients have been exposed to chronic lifelong immunosuppression. In this Review, the overall incidence and most frequent types of cancer encountered are summarized, along with information about which transplant recipients are at the greatest risk of malignancy. Reasons for why differences exist in susceptibility to cancer in this patient population are examined, and approaches that might improve our understanding of the options available for reducing the incidence of this adverse effect of immunosuppression are described. Whether anti-rejection drugs have been successful in diminishing overall immunosuppressive burden, and consequently show any promise for decreasing post-transplant malignancies is also discussed. The topic shifts to one class of conventional anti-rejection drugs, the mammalian target of rapamycin (mTOR) inhibitors, which paradoxically have both immunosuppressive and anti-neoplastic properties. The complex activities of mTOR are reviewed in order to provide context for how these seemingly opposing effects are possible, and the latest clinical data on use of mTOR inhibitors in the clinic are discussed. The current and future perspectives on how best to normalize these unacceptably high rates of post-transplantation malignancies are highlighted.

Honey in the Prevention and Treatment of Infection in the CKD Population: A Narrative Review

Infection is a major cause of morbidity and mortality at all stages of chronic kidney disease (CKD). Multiresistant organisms are becoming increasingly common, particularly in the CKD population. Unfortunately, the rapid evolution of antibiotic resistance has not been mirrored by innovation in new antibiotic agents. Novel treatments are therefore urgently needed. Honey has garnered much interest due to its broad-spectrum antibacterial properties based on extensive experimental data. Unlike conventional antibiotics, honey has an added advantage as it appears to avoid inducing antimicrobial resistance in bacteria. This review discusses the potential mechanisms of action and role of honey in infection management in the general population, epidemiology and special challenges of infections in CKD populations, and the clinical trial evidence pertaining to the safety and efficacy of honey for the prevention and treatment of infections in CKD population.

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.

Belatacept for kidney transplant recipients

BACKGROUND

Most people who receive a kidney transplant die from either cardiovascular disease or cancer before their transplant fails. The most common reason for someone with a kidney transplant to lose the function of their transplanted kidney necessitating return to dialysis is chronic kidney transplant scarring. Immunosuppressant drugs have side effects that increase risks of cardiovascular disease, cancer and chronic kidney transplant scarring. Belatacept may provide sufficient immunosuppression while avoiding unwanted side effects of other immunosuppressant drugs. However, high rates of post-transplant lymphoproliferative disease (PTLD) have been reported when belatacept is used in particular kidney transplant recipients at high dosage.

OBJECTIVES

1) Compare the relative efficacy of belatacept versus any other primary immunosuppression regimen for preventing acute rejection, maintaining kidney transplant function, and preventing death. 2) Compare the incidence of several adverse events: PTLD; other malignancies; chronic transplant kidney scarring (IF/TA); infections; change in blood pressure, lipid and blood sugar control. 3) Assess any variation in effects by study, intervention and recipient characteristics, including: differences in pre-transplant Epstein Barr virus serostatus; belatacept dosage; and donor-category (living, standard criteria deceased, or extended criteria deceased).

SEARCH METHODS

We searched the Cochrane Renal Group's Specialised Register to 1 September 2014 through contact with the Trials' Search Co-ordinator using search terms relevant to this review.

SELECTION CRITERIA

Randomised controlled trials (RCT) that compared belatacept versus any other immunosuppression regimen in kidney transplant recipients were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data for study quality and transplant outcomes and synthesized results using random effects meta-analysis, expressed as risk ratios (RR) and mean differences (MD), both with 95% confidence intervals (CI).  Subgroup analyses and univariate meta-regression were used to investigate potential heterogeneity.

MAIN RESULTS

We included five studies that compared belatacept and calcineurin inhibitors (CNI) that reported data from a total of 1535 kidney transplant recipients. Of the five studies, three (478 participants) compared belatacept and cyclosporin and two (43 recipients) compared belatacept and tacrolimus. Co-interventions included basiliximab (4 studies, 1434 recipients); anti-thymocyte globulin (1 study, 89 recipients); alemtuzumab (1 study, 12 recipients); mycophenolate mofetil (MMF, 5 studies, 1509 recipients); sirolimus (1 study, 26 recipients) and prednisone (5 studies, 1535 recipients).Up to three years following transplant, belatacept and CNI-treated recipients were at similar risk of dying (4 studies, 1516 recipients: RR 0.75, 95% CI 0.39 to 1.44), losing their kidney transplant and returning to dialysis (4 studies, 1516 recipients: RR 0.91, 95% CI 0.61 to 1.38), and having an episode of acute rejection (4 studies, 1516 recipients: RR 1.56, 95% CI 0.85 to 2.86). Belatacept-treated kidney transplant recipients were 28% less likely to have chronic kidney scarring (3 studies, 1360 recipients: RR 0.72, 95% CI 0.55 to 0.94) and also had better graft function (measured glomerular filtration rate (GFR) (3 studies 1083 recipients): 10.89 mL/min/1.73 m², 95% CI 4.01 to 17.77; estimated GFR (4 studies, 1083 recipients): MD 9.96 mL/min/1.73 m², 95% CI 3.28 to 16.64) than CNI-treated recipients. Blood pressure was lower (systolic (2 studies, 658 recipients): MD -7.51 mm Hg, 95% CI -10.57 to -4.46; diastolic (2 studies, 658 recipients): MD -3.07 mm Hg, 95% CI -4.83 to -1.31, lipid profile was better (non-HDL (3 studies 1101 recipients): MD -12.25 mg/dL, 95% CI -17.93 to -6.57; triglycerides (3 studies 1101 recipients): MD -24.09 mg/dL, 95% CI -44.55 to -3.64), and incidence of new-onset diabetes after transplant was reduced by 39% (4 studies (1049 recipients): RR 0.61, 95% CI 0.40 to 0.93) among belatacept-treated versus CNI-treated recipients.Risk of PTLD was similar in belatacept and CNI-treated recipients (4 studies, 1516 recipients: RR 2.79, 95% CI 0.61 to 12.66) and was no different among recipients who received different belatacept dosages (high versus low dosage: ratio of risk ratios (RRR) 1.06, 95% CI 0.11 to 9.80, test of difference = 0.96) or among those who were Epstein Barr virus seronegative compared with those who were seropositive before their kidney transplant (seronegative versus seropositive; RRR 1.49, 95% CI 0.15 to 14.76, test for difference = 0.73).The belatacept dose used (high versus low), type of donor kidney the recipient received (extended versus standard criteria) and whether the kidney transplant recipient received tacrolimus or cyclosporin made no difference to kidney transplant survival, incidence of acute rejection or estimated GFR. Selective outcome reporting meant that data for some key subgroup comparisons were sparse and that estimates of the effect of treatment in these groups of recipients remain imprecise.

AUTHORS' CONCLUSIONS

There is no evidence of any difference in the effectiveness of belatacept and CNI in preventing acute rejection, graft loss and death, but treatment with belatacept is associated with less chronic kidney scarring and better kidney transplant function. Treatment with belatacept is also associated with better blood pressure and lipid profile and a lower incidence of diabetes versus treatment with a CNI. Important side effects (particularly PTLD) remain poorly reported and so the relative benefits and harms of using belatacept remain unclear. Whether short-term advantages of treatment with belatacept are maintained over the medium- to long-term or translate into better cardiovascular outcomes or longer kidney transplant survival with function remains unclear. Longer-term, fully reported and published studies comparing belatacept versus tacrolimus are needed to help clinicians decide which patients might benefit most from using belatacept.

Adipose tissue-derived stem cells suppress acute cellular rejection by TSG-6 and CD44 interaction in rat kidney transplantation

BACKGROUND

In addition to its abundance and easy accessibility, adipose tissue yields more potent immunoregulatory stem cells (adipose tissue-derived stem cells, ADSCs) than does bone marrow. However, the beneficial effects of ADSCs on alloreactivity are scarcely known. This study evaluated the beneficial effects of ADSCs in rat kidney transplantation and analyzed the underlying molecular mechanism.

METHODS

Dark Agouti rat kidneys were transplanted into Lewis rats. Autologous ADSCs (2×10) were injected through the left renal artery of the donors before the nephrectomy (ADSCs group). Graft survival, histologic changes, and the expression of several cytokines and proteins were assessed. In an in vitro experiment, the immunosuppressive capacity of ADSCs was tested in a mixed lymphocyte reaction.

RESULTS

Histologic findings of the ADSCs group revealed a reduced rejection grade, whereas the number of infiltrated CD4/CD8 T cells was also significantly decreased as compared to the control. Relative to these findings, injection of ADSCs led to a significantly prolonged mean graft survival compared with the control. In vitro, autologous ADSCs dose-dependently suppressed alloreactive lymphocytes. Moreover, ADSCs increased the level of tumor necrosis factor-inducible gene 6 protein (TSG-6) in mixed lymphocyte reaction, which has an anti-inflammatory capacity. Recombinant TSG-6 markedly suppressed alloreactive T cells through downregulating CD44, which may lead to the suppression of T-cell activation and infiltration into allografts.

CONCLUSION

Our findings clearly showed that ADSCs attenuated acute rejection by secreting TSG-6 as well as through direct cell interaction. These findings contribute to the clinical application of these cells in solid organ transplantation.

ABO incompatible renal transplants: Good or bad?

ABO incompatible kidney transplantation (ABOi-KT) was previously considered to be an absolute contraindication for patients with end-stage kidney disease (ESKD) due to hyperacute rejection related to blood type barrier. Since the first successful series of ABOi-KT was reported, ABOi-KT is performed increasingly all over the world. ABOi-KT has led to an expanded donor pool and reduced the number of patients with ESKD awaiting deceased kidney transplantation (KT). Intensified immunosuppression and immunological understanding has helped to shape current desensitization protocols. Consequently, in recent years, ABOi-KT outcome is comparable to ABO compatible KT (ABOc-KT). However, many questions still remain unanswered. In ABOi-KT, there is an additional residual immunological risk that may lead to allograft damage, despite using current diverse but usually intensified immunosuppressive protocols at the expense of increasing risk of infection and possibly malignancy. Notably, in ABOi-KT, desensitization and antibody reduction therapies have increased the cost of KT. Reassuringly, there has been an evolution in ABOi-KT leading to a simplification of protocols over the last decade. This review provides an overview of the history, outcome, protocol, advantages and disadvantages in ABOi-KT, and focuses on whether ABOi-KT should be recommended as a therapeutic option of KT in the future.

Malignancies: pre and post transplantation strategies

The overall incidence of cancer is increased 2-3 fold in solid organ transplant recipients compared to the general population. The increase in risk is not uniform for all malignancies, in all ages or in all regions of the world. Several cancers are greatly increased, many are increased 2-4 fold and others do not appear to be increased at all. The pattern of increase is similar to patients with acquired immunodeficiency syndrome and those cancers most increased are associated with viral infections. These observations support the concept that much of the increased risk is from immunosuppression. Nonetheless there are differences between specific organ groups that deserve further examination. Those with advanced organ failure are also at increased risk for certain malignancies, which suggest either organ damage per se may pre-dispose to cancers or there are exposures to carcinogens in common. The purpose of this review to examine cancer incidence and mortality in solid organ transplantation and the role of pre transplant screening and post-transplant surveillance to reduce the burden of disease and improve patient outcomes. This review will focus on cancers that are common, associated with significant case fatality rates and have potential screening strategies to reduce burden of disease.

De novo cancer-related death in Australian liver and cardiothoracic transplant recipients

Evidence is sparse on the relative mortality risk posed by de novo cancers in liver and cardiothoracic transplant recipients. A retrospective cohort study was conducted in Australia using population-based liver (n = 1926) and cardiothoracic (n = 2718) registries (1984-2006). Standardized mortality ratios (SMRs) were computed by cancer type, transplanted organ, recipient age and sex. During a median 5-year follow-up, de novo cancer-related mortality risk in liver and cardiothoracic recipients was significantly elevated compared to the matched general population (n = 171; SMR = 2.83; 95% confidence interval [95%CI], 2.43-3.27). Excess risk was observed regardless of transplanted organ, recipient age group or sex. Non-Hodgkin lymphoma was the most common cancer-related death (n = 38; SMR = 16.6; 95%CI, 11.87-22.8). The highest relative risk was for nonmelanocytic skin cancer (n = 23; SMR = 49.6, 95%CI, 31.5-74.5), predominantly in males and in recipients of heart and lung transplants. Risk of death from de novo cancer was high in pediatric recipients (n = 5; SMR = 41.3; 95%CI, 13.4-96.5), four of the five deaths were non-Hodgkin lymphoma. De novo cancer was a leading cause of late death, particularly in heart and liver transplantation. These findings support tailored cancer prevention strategies, surveillance to promote early detection, and guidelines for managing immunosuppression once cancer occurs.

A surveillance model for skin cancer in organ transplant recipients: a 22-year prospective study in an ethnically diverse population

Skin cancer is a frequent complication of organ transplantation. Current guidelines advise specialist skin surveillance but there are limited data on how these should be implemented. This study determines overall burden of cancer and relevant intervals for strategic surveillance in an ethnically diverse transplant population. Prospective data on time to first and subsequent cancers and cumulative burden with respect to defined risk factors were analyzed in a cohort of 1010 patients in a UK center over 22 years. Among 931 individuals transplanted >6 months (mean 10.3 years), 1820 skin cancers occurred in 267 (29%) individuals and were multiple in 66%. Cumulative incidence at 5, 10, 20 and 30 years was 11%, 25%, 54% and 74%, with median time to second, third and fourth cancers of 24, 14.7 and 8.4 months, respectively. Tumors were overwhelmingly squamous and basal cell carcinomas (73% and 24%, respectively). Skin phototype, ultraviolet radiation exposure, age at transplant and duration of transplant were significant risk predictors and were used to construct clinically relevant surveillance intervals. This study provides a comprehensive, prospective analysis of skin cancer morbidity and risk in an ethnically diverse transplant population from which we derive an evidence-based skin cancer surveillance program.

Foxp3+ T cells in peripheral blood of renal transplant recipients and clinical correlations

AIM

Immunophenotype peripheral blood T cells from renal transplant recipients (RTR) using cellular markers of regulatory T cells (Tregs) and flow cytometry, including Foxp3, and correlate these findings with clinical parameters.

METHODS

Expression of phenotypic markers of Tregs was assessed by flow cytometric analysis of peripheral blood lymphocytes (PBL) from (i) RTR (n = 95); (ii) patients with end-stage renal failure (ESRF) awaiting transplantation (n = 17); and (iii) normal healthy controls (n = 18).

RESULTS

The percentage of CD4(+) CD25(+) Foxp3(+) cells within the CD4(+) cell population did not significantly alter at different time points post-transplant. However, the percentage of CD4(+) CD25(+) Foxp3(+) cells within the CD4(+) population was significantly lower in RTR compared with patients with ESRF. In contrast, RTR and ESRF had a similar percentage of CD4(+) CD25(+) cells expressing Foxp3. Multivariate analysis of PBL and clinical parameters demonstrated (i) a positive linear relationship between the percentage CD4(+) CD25(+) cells expressing Foxp3 and estimated glomerular filtration rate and (ii) a higher percentage of CD4(+) CD25(+) cells in the CD4(+) cell population in patients with malignancy (the majority were skin cancers). Malignancy also correlated strongly with time post-transplant and age of the RTR.

CONCLUSION

Immune monitoring of the PBL phenotype in RTR using CD4, CD25 and Foxp3 may stratify RTR and predict graft outcome and function, and risk of complications from immunosuppression. Longitudinal and functional studies of Tregs are essential to extend the findings of the present study.

[Risk of cancer in patients following chronic dialysis and kidney graft]

BACKGROUND

A high prevalence of renal insufficiency has been observed in cancer patients as well as a high incidence of de novo cancer in dialysis or renal transplant patients.

MATERIAL AND METHODS

We aimed to determine the incidence of cancer in patients under dialysis and in kidney transplant recipients through a search of the literature.

RESULTS

Under chronic dialysis, the risk of cancer increases from 1.1 to 1.8 in comparison to the general population. These risks reach 2.5 to 3.9 in renal transplant patients, but depend on the type of tumor.

CONCLUSION

In transplant recipients, the risk of cancer induced by immunosuppressive therapy requires a specific follow-up and a screening for any medical history of cancer in the donor and the recipient.

Sun exposure may increase risk of prostate cancer in the high UV environment of New South Wales, Australia: a case-control study

Ultraviolet (UV) radiation in sunlight may influence risk of prostate cancer. In New South Wales (NSW), Australia, we examined the relationship between sun exposure at 30 and 50 years of age and risk of prostate cancer in a case-control study combining the NSW prostate cancer care and outcome study (cases) and the NSW non-Hodgkin's lymphoma study (controls). Prostate cancer risk increased with increasing estimated sun exposure (adjusted OR for highest vs. lowest quartiles of average weekly sun exposure in the warmer months 2.07 95% CI: 1.36-3.15) and this increase was most evident with weekend sun exposure (adjusted OR=5.55, 95% CI: 2.94-10.48). High sun sensitivity was also positively associated with risk for prostate cancer (adjusted OR=1.63, 95% CI: 1.09-2.44). The apparent effects of weekly sun exposure did not vary by disease aggressiveness. Our results suggest that increasing sun exposure in mid-adult years increases prostate cancer risk in a high ambient solar UV environment. Given that previous studies, conducted mainly in low solar UV environments, have generally found evidence of a negative association, our findings suggest there may be a U-shaped relationship between solar UV exposure and prostate cancer. Further studies are needed to test the hypothesis that high solar UV exposure is a risk factor for prostate cancer and to explore possible mechanisms for such an association.

Genome-wide screening for genes associated with FK506 sensitivity in fission yeast

We have been studying calcineurin signal transduction pathway in fission yeast Schizosaccharomyces pombe (S. pombe) by developing a genetic screen for mutants that show hypersensitivity to the immunosuppressive calcineurin inhibitor FK506 (tacrolimus). In the present study, to identify nonessential genes that are functionally related to the calcineurin signaling pathway, we performed a genome-wide screen of 3004 haploid deletion strains and confirmed 72 deletion strains to be FK506 sensitive. These 72 genes are classified into nine functional groups to include membrane trafficking (16 genes), signal transduction (10 genes), ubiquitination (8 genes), chromatin remodeling (6 genes), cytokinesis (4 genes), ribosomal protein (3 genes), RNA binding protein (3 genes), and a variety of other known functions (17 genes) or still unknown functions (5 genes) in the biological system. In our previous screening of FK506-sensitive mutants we isolated several membrane-trafficking mutants showing defective cell wall integrity. Here, we further examined the vacuolar fusion, the v-SNARE synaptobrevin Syb1 localization, and the sensitivity to the β-glucan synthase inhibitor micafungin in these 72 FK506-sensitive strains. Results showed that 25 deletion strains exhibited abnormal vacuole fusion, 19 deletion strains exhibited Syb1 mislocalization, and 14 deletion strains exhibited both abnormal vacuole fusion and Syb1 mislocalization, while 42 deletion strains showed both normal vacuole fusion and Syb1 localization. Likewise, 16 deletion strains showed sensitivity to micafungin. Altogether, our present study indicates that calcineurin mediates a plethora of physiological processes in fission yeast, and that calcineurin is extensively involved in cross-talk between signaling pathways.

Incidence and clinicopathologic behavior of uterine cervical carcinoma in renal transplant recipients

BACKGROUND

Renal allograft recipients are reported to have a higher incidence of malignancy than the general population. This single hospital-based study examined the incidence and clinicopathologic behavior of uterine cervical carcinoma in renal transplant recipients.

METHODS

Among 453 women receiving renal transplantation from January 1990 to December 2008, 5 patients were diagnosed with cervical carcinoma. Medical records of these 5 patients were retrospectively reviewed, and clinicopathologic data were collected and analyzed.

RESULTS

The incidence of cervical carcinoma in renal transplant recipients was 58.1 out of 100,000 per year, which is 3.5 times higher than in the general Korean population. The mean interval between the time of renal transplantation and the time of cervical carcinoma diagnosis was 80.7 months. After a median follow-up of 96.2 months, there was no recurrence of the disease or death. In 4 patients who were positive from human papillomavirus in situ hybridization (HPV ISH), high or probably high risk HPV DNA was detected in all. Punctate staining of HPV ISH was detected in 3 out of 4 patients.

CONCLUSIONS

Higher incidence of cervical carcinoma is expected in renal transplant recipients, so appropriate surveillance is needed to ensure early detection and treatment of cervical carcinoma.

High incidence and recurrence of transitional cell carcinoma in Taiwanese patients with end-stage renal disease

AIM

This study examines the epidemiology of transitional cell carcinoma (TCC) in end-stage renal disease (ESRD) population from Taiwan, the area with the highest incidence and prevalence of ESRD.

METHODS

A total of 98 out of 10,890 ESRD patients were referred for management of TCC between 2000 and 2008. Demographic, clinical and laboratory data were collected and patient mortality and tumour recurrence rates were analyzed.

RESULTS

TCC patients were aged 61.4 ± 10.2 years and 66.3% were female. The average time from initiation of dialysis to tumour detection was 51.2 ± 36.4 months. Hypertensive nephrosclerosis, diabetes mellitus, chronic glomerulonephritis and unknown aetiology accounted for 25.5%, 20.4%, 22.4% and 31.6% of the causes of renal failure, respectively. The aetiology of renal failure for the 31.6% of patients was unclear, but chronic tubulointerstitial nephritis following long-term consumption of Chinese herbs (19.4%) or analgesic compounds (3.1%) was considered in some patients. Almost all (98.0%) patients presented with gross haematuria. Most TCC were in early stage (stage 0, 3.1%; stage I, 56.1%) during diagnosis. At the end of this study, 17 of 98 (17.3%) patients died. Multivariate Cox regression analysis found that age (odds ratio =1.140, 95% confidence interval = 1.049-1.239, P = 0.002) and tumour pain (odds ratio = 0.234, 95% confidence interval = 0.057-0.961, P = 0.044) were significant risk factors for all-cause mortality. Furthermore, 35.7% of TCC recurred during follow up. The 5 year patient and tumour-free survival rates were 72.4% and 14.4%, respectively.

CONCLUSION

The data shows that Taiwanese patients with ESRD had high incidence (0.9%) and recurrence (35.7%) of TCC.

Malignancy after renal transplantation: the role of immunosuppression

Outcomes of kidney transplantation, in terms of graft and patient survival, have improved over the past few decades, partly as a result of the introduction of new immunosuppressive drugs. Many immunosuppressive agents are associated with an increased risk of cardiovascular events and an increased risk of cancer, however, which can compromise patient survival. Cancer is more common among solid-organ transplant recipients than it is in the general population or in patients on dialysis. In fact, malignancy is the third most common cause of death in renal transplant recipients. Immunosuppressive treatments used in renal transplant recipients can cause malignancy by supporting oncogenesis caused by certain viruses or by impairing immune surveillance thereby enabling faster tumor growth. In this Review, we describe the epidemiological and clinical characteristics of common tumor types occurring after kidney transplantation, and the etiopathogenetic factors that lead to their appearance, with a particular focus on the relationship between immunosuppressive treatment and malignancy. Immunosuppressive drugs associated with an increased risk of malignancy after transplantation are also discussed, as are immunosuppressive drugs that seem to have antioncogenic properties.

De novo malignancy is associated with renal transplant tourism

Despite the objections to transplant tourism raised by the transplant community, many patients continue travel to other countries to receive commercial transplants. To evaluate some long-term complications, we reviewed medical records of 215 Taiwanese patients (touring group) who received commercial cadaveric renal transplants in China and compared them with those of 321 transplant recipients receiving domestic cadaveric renal transplants (domestic group) over the same 20-year period. Ten years after transplant, the graft and patient survival rates of the touring group were 55 and 81.5%, respectively, compared with 60 and 89.3%, respectively, of the domestic group. The difference between the two groups was not statistically significant. The 10-year cumulative cancer incidence of the touring group (21.5%) was significantly higher than that of the domestic group (6.8%). Univariate and multivariate stepwise regression analyses (excluding time on immunosuppression, an uncontrollable factor) indicated that transplant tourism was associated with significantly higher cancer incidence. Older age at transplantation was associated with a significantly increased cancer risk; however, the risk of de novo malignancy significantly decreased with longer graft survival. Thus, renal transplant tourism may be associated with a higher risk of post-transplant malignancy, especially in patients of older age at transplantation.

Comparison of the incidence of malignancy in recipients of different types of organ: a UK Registry audit

An increased incidence of malignancy is an established complication of organ transplantation and the associated immunosuppression. In this study on cancer incidence in solid organ transplant recipients in Britain, we describe the incidence of de novo cancers in the allograft recipient, and compare these incidences following the transplantation of different organs. Data in the UK Transplant Registry held by NHS Blood and Transplant (NHSBT) were linked with data made available by the cancer registries in England, Scotland and Wales. Incidence rates in the transplanted population were then compared with the general population, using standardized incidence ratios matched for age, gender and time period. The 10-year incidence of de novo cancer in transplant recipients is twice that of the general population, with the incidence of nonmelanoma skin cancer being 13 times greater. Nonmelanoma skin cancer, cancer of the lip, posttransplant lymphoproliferative disease and anal cancer have the largest standardized incidence ratios, but the incidence of different types of malignancy differs according to the organ transplanted. Patterns in standardized incidence ratios over time since transplantation are different for different types of transplant recipient, as well as for different malignancies. These results have implications for a national screening program.

Topics in transplantation medicine for general nephrologists

Before transplantation, the general nephrologist is the primary resource for potential kidney transplantation recipients. After transplantation, the general nephrologist is increasingly managing transplant medications and complications. We provide evidence-based management strategies for common clinical issues. Linking our approach with the data allows the clinician to explore each subject in greater depth to tailor care to individual patients.

Chronic kidney disease and cancer: a troubling connection

Chronic kidney disease (CKD) and cancer are connected in a number of ways in both directions: cancer can cause CKD either directly or indirectly through the adverse effects of therapies; CKD may, conversely, be a risk factor for cancer; and both may be associated because they share common risk factors, often toxins. In this review, we briefly address the issue of paraneoplastic nephropathies as well as that of toxin-related cancers and CKD, including analgesic and aristolochic acid nephropathies. We then focus on the links between the various stages of CKD and cancer incidence, and critically examine major epidemiologic surveys in the field. Compared with the general population, kidney transplant recipients have a threefold to fourfold increase in overall cancer risk, and relative risks higher than 3 for about 20 specific tumors, most, but not all, of which are known or suspected to be caused by viral agents. After dialysis, cancer risk increases 10% to 80% according to studies, with relative risks significantly higher than in the general population, for about 10 cancer sites. There is emerging evidence for an excess risk of cancer in patients in early CKD stages.

Immune phenotype predicts risk for posttransplantation squamous cell carcinoma

Cutaneous squamous cell cancer (SCC) affects up to 30% of kidney transplant recipients (KTRs) within 10 years of transplantation. There are no reliable clinical tests that predict those who will develop multiple skin cancers. High numbers of regulatory T cells associate with poor prognosis for patients with cancer in the general population, suggesting their potential as a predictive marker of cutaneous SCC in KTRs. We matched KTRs with (n = 65) and without (n = 51) cutaneous SCC for gender, age, and duration of immunosuppression and assessed several risk factors for incident SCC during a median follow-up of 340 days. Greater than 35 peripheral FOXP3(+)CD4(+)CD127(low) regulatory T cells/microl, <100 natural killer cells/microl, and previous SCC each significantly associated with increased risk for new cutaneous SCC development (hazard ratio [HR] 2.48 [95% confidence interval (CI) 1.04 to 5.98], HR 5.6 [95% CI 1.31 to 24], and HR 1.33 [95% CI 1.15 to 1.53], respectively). In addition, the ratio of CD8/FOXP3 expression was significantly lower in cutaneous SCC excised from KTRs (n = 25) compared with matched SCC from non-KTRs (n = 25) and associated with development of new cutaneous SCCs. In summary, monitoring components of the immune system can predict development of cutaneous SCC among KTRs.

Cancer incidence and risk factors after solid organ transplantation

Iatrogenic immunosuppression is a unique setting for investigating immune-related mechanisms of carcinogenesis. Solid organ transplant recipients have a 3-fold excess risk of cancer relative to the age- and sex-matched general population. Population-based studies utilizing cancer registry records indicate that a wide range of cancers, mostly those with a viral etiology, occur at excess rates. To date, cancer risk has predominantly been examined in adult kidney transplant recipients in Western countries. It is yet to be established whether a similar incidence profile exists in the long-term for other solid organ, pediatric and non-Western transplant recipients. The cancer incidence profile before and after kidney transplantation strongly suggests a relatively minor contribution by both preexisting cancer risk factors and the conditions underlying end-stage kidney disease, and points to a causal role for immunosuppression. Within-cohort risk factor analyses have largely been performed on cohorts with voluntary cancer notification, and very few have incorporated biomarkers of the level of immunosuppression, the current receipt of immunosuppressive agents, or genetic risk factors. Because of their markedly high risk of certain cancers, findings from comprehensive studies in transplant recipients have the potential to raise new avenues for investigation into causal mechanisms and preventive measures against immune-related and infectious causes of cancer.

Minimizing the risk of posttransplant malignancy

Nowadays cancer represents the second main cause of death in renal transplant patients with normal function of the graft. The incidence is 10 to 20 times higher than normal population. Calcineurin inhibitor therapy contributes to the increase in the development of neoplasia. Important evidence could bring a preventive effect of mammalian target of rapamycin in skin cancer, Kaposi's sarcoma, and renal cell carcinoma.