Malignancy after renal transplantation: the role of immunosuppression

Rate differences between first and second primary cancers may outline immune dysfunction as a key risk factor

Background

Many cancers are increased in immunosuppressed patients and evidence is accumulating that immune dysfunction may be a contributing risk factor for second primary cancers (SPCs). The aim of this study was to explore the potential influence of immune mechanisms in SPC.

Methods

We used the Swedish Cancer Registry (1990‐2015) to select 13 male and 14 female first primary cancers (FPCs) that are known to be related to immune suppression. We assessed relative risks (RRs) for any of these as concordant (same first and second cancer) and discordant FPC‐SPC pairs. Hierarchical clustering of significant RRs was performed for cancers as FPC and SPC.

Results

Concordant risks for SPCs were excessive in men and women for nasal (RRs 59.3 for men and 150.6 for women), tongue/mouth (51.7 and 100.8), and lip (32.4 and 61.2) cancers. Heatmaps showed that some cancers, such as skin cancer, tongue/mouth cancers, and non‐Hodgkin lymphoma had multiple bidirectional associations as FPC and SPC. Nasal cancer and chronic lymphocytic leukemia had associations mainly as FPC while liver and kidney cancers showed most associations as SPC.

Conclusions

Immune dysfunction may be a plausible contributing factor for most of the associations, which calls for experimental verification.

Efficacy and tolerance of immune checkpoint inhibitors in transplant patients with cancer: A systematic review

Solid organ transplant (SOT) is frequently complicated by cancers, which render immunosuppression challenging. Immune checkpoint inhibitors have emerged as treatments for many cancers. Data are lacking regarding efficacy and rejection risk in the SOT population. We conducted a systematic literature review and analyzed 83 cases of immune checkpoint inhibitor use for cancer in SOT. Two thirds of these patients received anti-programmed death ligand 1 therapy, 15.7% received anti-cytotoxic T lymphocyte-associated protein 4 therapy, and 10.8% received a combination. Allograft rejection occurred in 39.8% of patients, leading to end-stage organ failure in 71.0% of cases. Outcomes were similar across organs and immunotherapy regimens. The use of immunosuppressants other than steroids, time since transplant, and prior episodes of rejection were associated with the risk of rejection. The median overall survival of patients was 36 weeks. Most of the deaths were related to cancer progression. In nonkidney recipients, graft rejection was strongly associated with worse survival. At the end of the study, 19.3% of the patients were alive, free from rejection and tumor progression. This study highlights the difficult tradeoff facing oncologists and transplant specialists managing transplant recipients with cancer, and the need for prospective data and novel biomarkers for identifying the patients likely to benefit from immunotherapy in the SOT setting.

Risk of Genitourinary Malignancy in the Renal Transplant Patient

OBJECTIVE

To better understand the risk of genitourinary malignancies in the renal transplant patient. Currently, no consensus exists regarding screening and intervention, with much of the clinical decision-making based on historical practices established before recent progress in immunosuppression protocols and in genitourinary cancer diagnosis and management.

METHODS

A database of all solid organ transplants performed at the University of Minnesota from 1984 to 2019 was queried for renal transplant recipients in whom development of subsequent urologic malignancies (prostate, bladder, renal, penile, and testicular cancer) was found.

RESULTS

Among 6172 renal transplant recipients examined, cumulative incidence of all cancers of genitourinary etiology are presented over an average follow-up time of 10 years. Kidney cancer (combined graft and native), prostate cancer, and bladder cancer each demonstrated respective 30-year incidence of 4.6%, 8.7%, and 1.5% from the time of transplant. By comparison, age-matched data from the Surveillance, Epidemiology, and End Results database demonstrated 30-year cumulative incidence of 1.1%, 11.1%, and 1.7% for kidney cancer, prostate cancer, and bladder cancer respectively. The predominant genitourinary cancer was renal cell cancer, both of the native and of the transplanted kidney (native, n = 64; transplanted, n =11), followed by prostate cancer (n = 63), and bladder cancer (n = 37).

CONCLUSION

In this closely followed cohort of renal transplant recipients, renal cancer occurs at a higher incidence rate than in the non-transplanted population, while a lower rate of prostate cancer was found, with bladder cancer demonstrating a comparable cumulative incidence between transplant patients and the national age-matched population.

Antigen-reactive regulatory T cells can be expanded in vitro with monocytes and anti-CD28 and anti-CD154 antibodies

BACKGROUND

In recent years, therapies with CD4⁺CD25^highFoxP3⁺ regulatory T cells (Tregs) have been successfully tested in many clinical trials. The important issue regarding the use of this treatment in autoimmune conditions remains the specificity toward particular antigen, as because of epitope spread, there are usually multiple causative autoantigens to be regulated in such conditions.

METHODS

Here we show a method of generation of Tregs enriched with antigen-reactive clones that potentially covers the majority of such autoantigens. In our research, Tregs were expanded with anti-CD28 and anti-CD154 antibodies and autologous monocytes and loaded with a model peptide, such as whole insulin or insulin β chain peptide 9-23. The cells were then sorted into cells recognizing the presented antigen. The reactivity was verified with functional assays in which Tregs suppressed proliferation or interferon gamma production of autologous effector T cells (polyclonal and antigen-specific) used as responders challenged with the model peptide. Finally, we analyzed clonotype distribution and TRAV gene usage in the specific Tregs.

RESULTS

Altogether, the applied technique had a good yield and allowed us to obtain a Treg product enriched with a specific subset, as confirmed in the functional tests. The product consisted of many clones; nevertheless, the content of these clones was different from that found in polyclonal or unspecific Tregs.

CONCLUSIONS

The presented technique might be used to generate populations of Tregs enriched with cells reactive to any given peptide, which can be used as a cellular therapy medicinal product in antigen-targeted therapies.

Incidence Differences Between First Primary Cancers and Second Primary Cancers Following Skin Squamous Cell Carcinoma as Etiological Clues

Background

Most literature on second primary cancers (SPCs) focuses on possible factors, which may increase the risk of these cancers, and little attention has been paid for the overall incidence differences between first primary cancers (FPCs) and same SPCs. We wanted to compare the incidence rates for all common cancers when these were diagnosed as FPCs and SPCs after invasive and in situ squamous cell carcinoma (SCC) of the skin, which are usually treated by surgery only.

Methods

Cancers were identified from the Swedish Cancer Registry from the years 1990 through to 2015, and they included, in addition to skin cancers, 20 male cancers totaling 484,850 patients and 22 female cancers totaling 452,909 patients. Standardized incidence rates and relative risks (RRs) were calculated for sex-specific common cancers as FPC and as SPC after skin SCC. Spearman rank correlations were used in the analysis of incidence ranking of FPC and SPC.

Results

Of total, 29,061 men and 23,533 women developed invasive SCC and 27,842 men and 36,383 women in situ SCC. The total number of 20 other male cancers was 484,850 and of 22 female cancers it was 452,909. Rank correlations ranged from 0.90 to 0.96 (P~5×10^-6), indicating that overall skin SCC did not interfere with SPC formation. The exceptions were increased SPC risks for melanoma, sharing risk factors with skin SCC, and non-Hodgkin and Hodgkin lymphoma, and cancers of the upper aerodigestive tract, connective tissue, and male and female genitals suggesting contribution by skin cancer initiated immune dysfunction.

Conclusion

The incidence ranking of SPCs after skin cancers largely follows the incidence ranking of FPCs indicating that overall skin SCC does not greatly interfere with the intrinsic carcinogenic process. The main deviations in incidence between FPC and SPC appeared to be due to shared risk factors or immunological processes promoting immune responsive cancer types.

Gastrointestinal Pathologies in Patients After Successful Renal Transplantation

BACKGROUND

Kidney transplantation (KT) is the most desired and cost-effective modality of renal replacement therapy for patients with chronic kidney failure. KT protects the patient from complications that may develop during chronic dialysis. Unfortunately, evidence also suggests that KT patients are more prone to developing cancer than healthy persons. Many complications after renal transplantation can be prevented if they are detected early. The aim of this study was to evaluate the prevalence of gastrointestinal pathologies in patients after KT.

METHODS

Adult patients after KT who are under the care of the Outpatient Department of Nephrology at the Medical University of Gdańsk, Poland, received alarm symptom questionnaires and referral for testing for the presence of fecal occult blood. Then, in 58 selected patients (36 men and 22 women), endoscopic examination was performed. Mean age was 57.34 ± 10.1 (range, 35-83) years.

RESULTS

Out of 940 patients after KT, resting under supervision of the Outpatient Department, 208 patients completed the questionnaire and 118 gave a stool sample for testing: 40 results were positive. After analyzing the questionnaires and stool results, 100 patients qualified for further investigation. The endoscopic examination had been performed so far in 58 patients and revealed gastritis and/or duodenitis in 49 patients, diverticular colon disease in 26, esophagitis in 8, colon polyps in 16, stomach polyps in 4, inflammatory bowel disease in 12, and cancers in 3.

CONCLUSIONS

The preliminary results indicate that patients after KT have significant risk of gastrointestinal pathologies and require detailed diagnostic endoscopy.

Chimerism, Transplant Tolerance, and Beyond

The present review discusses current developments in tolerance induction for solid organ transplantation with a particular emphasis on chimerism-based approaches. It explains the basic mechanisms of chimerism-based tolerance and provides an update on ongoing clinical tolerance trials. The concept of "delayed tolerance" is presented, and ongoing preclinical studies in the nonhuman primate setting-including current limitations and hurdles regarding this approach-are illustrated. In addition, a brief overview and update on cell-based tolerogenic clinical trials is provided. In a critical approach, advantages, limitations, and potential implications for the future of these different regimens are discussed.

Recent Advances and Clinical Outcomes of Kidney Transplantation

Recent advances in surgical, immunosuppressive and monitoring protocols have led to the significant improvement of overall one-year kidney allograft outcomes. Nonetheless, there has not been a significant change in long-term kidney allograft outcomes. In fact, chronic and acute antibody-mediated rejection (ABMR) and non-immunological complications following kidney transplantation, including multiple incidences of primary kidney disease, as well as complications such as cardiovascular diseases, infections, and malignancy are the major factors that have contributed to the failure of kidney allografts. The use of molecular techniques to enhance histological diagnostics and noninvasive surveillance are what the latest studies in the field of clinical kidney transplant seem to mainly focus upon. Increasingly innovative approaches are being used to discover immunosuppressive methods to overcome critical sensitization, prevent the development of anti-human leukocyte antigen (HLA) antibodies, treat chronic active ABMR, and reduce non-immunological complications following kidney transplantation, such as the recurrence of primary kidney disease and other complications, such as cardiovascular diseases, infections, and malignancy. In the present era of utilizing electronic health records (EHRs), it is strongly believed that big data and artificial intelligence will reshape the research done on kidney transplantation in the near future. In addition, the utilization of telemedicine is increasing, providing benefits such as reaching out to kidney transplant patients in remote areas and helping to make scarce healthcare resources more accessible for kidney transplantation. In this article, we discuss the recent research developments in kidney transplants that may affect long-term allografts, as well as the survival of the patient. The latest developments in living kidney donation are also explored.

Changing pattern and safety of pretransplant malignancy in kidney transplant recipients

Background

Cancer rates are increasing not only in the general population but also in patients with end-stage renal disease. We investigated the changing pattern of pretransplant malignancy in kidney transplant recipients over 5 decades.

Methods

We reviewed 3,748 kidney transplant recipients between 1969 and 2016. We divided patients into three groups (1969-1998, 1999-2006, 2007-2016) based on the era of the cancer screening system used throughout the nation. We analyzed the incidence and pattern of pretransplant malignancy among the three groups. We also evaluated recurrent and de novo malignancy in these patients compared to patients without pretransplant malignancy.

Results

A total of 72 patients exhibited pretransplant malignancy (1.9%). There were no cases of pretransplant cancer until 1998, but the rate of pretransplant malignancy gradually increased to 1.1% during 1999-2006 and further increased to 4.3% thereafter. The most frequent types of pretransplant malignancy changed from the bladder, liver, and stomach cancers to thyroid cancer and renal cell carcinoma. There were no de novo cases, but there were three cases of recurrent cancer in patients with pretransplant malignancy; the recurrence rate among kidney transplant recipients with pretransplant malignancy was not significantly different from the incidence rate of de novo malignancy among kidney transplant recipients without pretransplant malignancy (4.2% vs. 6.9%, P = 0.48).

Conclusion

The incidence of pretransplant malignancy in kidney transplantation candidates is gradually increasing, and recent increases were accompanied by changes in cancer types. Pretransplant malignancy may not be a hindrance to kidney transplantation because of the low incidence of posttransplant recurrence and de novo malignancy.

Comparison of Familial Clustering of Anogenital and Skin Cancers Between In Situ and Invasive Types

Literature on familial risk of carcinomas in situ (CISs) is limited because many cancer registries do not collect information on CIS. In Sweden CISs are collected, and we used these data to analyze familial relative risks (RRs) for concordant (CIS-CIS) types of anogenital (cervical, other female and male genital and anal) and skin squamous cell CIS; additionally RRs were assessed between CIS types and between CIS and invasive forms. RRs were calculated for the offspring generations when family members were diagnosed CIS. Case numbers for CIS ranged from 330 in anal to 177,285 in cervical CIS. Significant concordant CIS-CIS RRs were 2.74 for female genital, 1.77 for cervical and 2.29 for SCC skin CISs. The CIS forms associated also with each other, except for cervical and skin CIS types. RRs for concordant CIS-invasive cancer associations were lower than CIS-CIS associations. Cervical CIS associated with non-Hodgkin CIS which may suggest immune dysfunction as a contributing factors. The results for anogenital CIS types suggest that life style related human papilloma virus infections contributed to the observed familial associations. Lower risks for CIS-invasive cancer than CIS-CIS suggest that CIS and invasive cancers share only partially risk factors that underlie familial clustering.

Immunosuppression following organ transplantation. Part 2: complications and their management

Advances in the care of patients who have had a solid organ transplant has led to a growing population of post-transplant patients, who are also living for longer. As a result of their longer life expectancy, transplant recipients often face a multitude of challenges, including optimising their immunosuppressive regimens and managing potential complications. Life-threatening infections, malignancies, and organ-specific toxicities are the complications post-transplant patients commonly encounter and these complications are often associated with increased morbidity and mortality, adverse graft functioning and survival, profound impairment in the patient's quality of life, and significant healthcare burden. This article, the second of two parts, gives an overview of the issues involved in the care of patients who are receiving immunosuppressants. The common complications encountered by post-transplant patients are discussed and their assessment, management, prevention and treatment explored.

Kidney transplantation for the primary care provider

Advancement in kidney transplantation has led to prolonged survival in our population with kidney disease. Newer agents of immunosuppression have made this possible with less rejections and lesser opportunistic infections and transplant related deaths. Preventative care like timely vaccines, cancer screenings, aggressive blood pressure, blood sugar, lipid control, timely referral to consultants is required in these patient population to provide quality care and to prolong their survival. Primary care physicians are the best advocate for our transplant populations. To care for these complex transplant patients, it is vital for primary care physicians to be familiar with the overall approach on our patients.

Risk of malignancy in patients with psoriasis: a 15-year nationwide population-based prospective cohort study in Korea

BACKGROUND

The association between psoriasis and risk of malignancy has not been thoroughly evaluated in a large longitudinal cohort of Asian population.

OBJECTIVE

To determine the long-term risk of malignancy in Korean adult patients with psoriasis.

METHODS

We conducted a nationwide population-based prospective cohort study with a 15-year observational period. During the baseline period (1997-2000), total 1 773 786 Korean subjects who received health insurance from the National Health Insurance System were enrolled and 5788 subjects were defined as a psoriasis group. The number of new-onset malignancy was collected during the observational period (2001-2015).

RESULTS

Patients with psoriasis had a higher adjusted hazard ratio (aHR) for development of overall malignancy [aHR 1.08, 95% confidence interval (CI) 1.00-1.18] and gastric cancer (aHR 1.31, 95% CI 1.08-1.58) compared to controls. The risks of non-Hodgkin lymphoma and non-melanoma skin cancer were significantly increased only in patients with psoriasis who received systemic treatments (aHR 2.86, 95% CI 1.07-7.61 and aHR 3.93, 95% CI 1.47-10.47, respectively).

CONCLUSION

Psoriasis is associated with long-term risk for overall malignancy in Koreans, which was primarily driven by the increased risk of gastric cancer.

Second Primary Cancers in Patients with Invasive and In Situ Squamous Cell Skin Carcinoma, Kaposi Sarcoma, and Merkel Cell Carcinoma: Role for Immune Mechanisms?

Second primary cancers (SPCs) are becoming a common cancer entity, which may interfere with survival in relatively benign first primary cancers. We examined the hypothesis that immune dysfunction may contribute to SPCs by assessing SPCs associated with known immune responsive skin cancers, invasive and in situ squamous cell carcinoma, Kaposi sarcoma, and Merkel cell carcinoma. Cancers were identified from the Swedish Cancer Registry from the year 1958 to 2015. Standardized relative risks were calculated bidirectionally for any SPC after skin cancer and for skin cancer as SPC. Over 80,000 first primary cancers were identified for each invasive and in situ squamous cell carcinoma of the skin. Bidirectional increased risks were observed for 26 cancers associated with invasive skin cancer; the Spearman rank correlation was 0.72 (P = 4.6 × 10^-5). The highest bidirectional relative risks were for invasive and in situ skin cancer as SPCs (14.59 and 16.71, respectively). Remarkably high risks for second in situ squamous cell carcinoma of the skin were found after Kaposi sarcoma (685.68) and Merkel cell carcinoma (117.23). The high systematic bidirectional risks between immune responsive skin cancers and most other cancers suggest that immune suppression is a key mechanism contributing to an increased risk of SPCs.

Mesenchymal Stromal Cells for Transplant Tolerance

In solid organ transplantation lifelong immunosuppression exposes transplant recipients to life-threatening complications, such as infections and malignancies, and to severe side effects. Cellular therapy with mesenchymal stromal cells (MSC) has recently emerged as a promising strategy to regulate anti-donor immune responses, allowing immunosuppressive drug minimization and tolerance induction. In this review we summarize preclinical data on MSC in solid organ transplant models, focusing on potential mechanisms of action of MSC, including down-regulation of effector T-cell response and activation of regulatory pathways. We will also provide an overview of available data on safety and feasibility of MSC therapy in solid organ transplant patients, highlighting the issues that still need to be addressed before establishing MSC as a safe and effective tolerogenic cell therapy in transplantation.

Diagnosis and Management of a De Novo Urothelial Carcinoma in a Kidney Allograft: A Case Report

INTRODUCTION

Following renal transplantation, the incidence of malignancies is 3-5 times higher than that of healthy individuals. Among other type of cancers, the risk of urological tumors is also elevated. However, only a few cases of de novo transitional cell carcinomas occurring in renal allografts have been reported.

CASE REPORT

A 63-year-old tertiary transplanted male patient was urgently hospitalized for a painless macroscopic hematuria. Ultrasonography revealed pyelectasis and a hematoma in the renal pelvis. A percutaneous nephrostomy tube was inserted. An anterograde pyelography was performed later, where a filling defect was still observable in the location of the previously reported hypoechoic mass. Contrast-enhanced ultrasonography showed enhancement of the lesion. An ultrasound-guided percutaneous biopsy was performed. The histologic evaluation revealed a high-grade transitional cell carcinoma. A whole-body staging computed tomography scan did not show signs of metastatic disease. The renal allograft was surgically removed. No disease progression was observed during the 21-month follow-up period.

CONCLUSIONS

Painless hematuria and asymptomatic hydronephrosis occurring after kidney transplantation should raise the possibility of urothelial carcinoma in the kidney graft. Contrast-enhanced ultrasound should be considered as a first-line diagnostic modality because it is easily accessible and does not raise concerns about nephrotoxicity or radiation burden.

Survival associated with chronic obstructive pulmonary disease among SEER-Medicare beneficiaries with non-small-cell lung cancer

Objective: We investigated the impact of preexisting COPD and its subtypes, chronic bronchitis and emphysema, on overall survival among Medicare enrollees diagnosed with non-small-cell lung cancer (NSCLC).

Methods: Using SEER-Medicare data, we included patients ≥66 years of age diagnosed with NSCLC at any disease stage between 2006 and 2010 and continuously enrolled in Medicare Parts A and B in the 12 months prior to diagnosis. Preexisting COPD in patients with NSCLC were identified using ICD-9 codes. Kaplan–Meier method and log-rank tests were used to examine overall survival by COPD status and COPD subtype. Multivariable Cox proportional hazards models were fit to assess the risk of death after cancer diagnosis.

Results: We identified 66,963 lung cancer patients. Of these, 22,497 (33.60%) had documented COPD before NSCLC diagnosis. For each stage of NSCLC, median survival was shorter in the COPD compared to the non-COPD group (Stage I: 692 days vs 1,130 days, P<0.0001; Stage II: 473 days vs 627 days, P<0.0001; Stage III: 224 days vs 229 days; P<0.0001; Stage IV: 106 days vs 112 days, P<0.0001). For COPD subtype, median survival for patients with preexisting chronic bronchitis was shorter compared to emphysema across all stages of NSCLC (Stage I: 672 days vs 811 days, P<0.0001; Stage II 582 days vs 445 days, P<0.0001; Stage III: 255 days vs 229 days, P<0.0001; Stage IV: 105 days vs 112 days, P<0.0001). In Cox proportional hazard model, COPD patients exhibited 11% increase in risk of death than non-COPD patients (HR: 1.11, 95%CI: 1.09–1.13).

Conclusion: NSCLC patients with preexisting COPD had shorter survival with marked differences in early stages of lung cancer. Chronic bronchitis demonstrated a greater association with time to death than emphysema.

Therapy with CD4+CD25+ T regulatory cells - should we be afraid of cancer?

This review focuses on the role of regulatory T cells (Tregs) in the process of carcinogenesis. The controversy of this issue arose due to the increasing therapeutic use of Tregs in humans (inter alia, in the treatment of autoimmune diseases). It is mainly due to potential dangers related to immunosuppressive activity of these cells, especially regarding cancer. The natural function of regulatory T cells (which is the suppression of excessive activity of the immune system) is purportedly linked to an increased risk of cancer initiation. This work brings together and summarizes the most important reports of researchers dealing with this problem and attempts to explain doubts and fears related to Tregs and their uncertain connection with cancer initiation and progression. It is clearly shown that regulatory T cells are associated with acceleration of existing tumors (they are attracted by microenvironments created by cancer cells) but cannot initiate them on their own.

Recurrence of Renal Cell Cancer After Renal Transplantation in a Multicenter French Cohort

BACKGROUND

Renal cancer accounts for 3% of adult malignancies; renal cell carcinoma (RCC) represents 80% of all renal cancers, and is characterized by late recurrences. Recurrences after kidney transplantation are associated with a high mortality rate. We aimed to determine if recurrences are linked to tumor characteristics and to delays between diagnosis and transplantation.

METHODS

We retrospectively analyzed data from French kidney-transplanted patients with medical histories of pretransplant renal cancer, focusing on the most common histological subtypes: clear cell and papillary cancers. Characteristics of the tumors, patients, and kidney transplantations were documented, and posttransplant patient survival was analyzed.

RESULTS

Of 143 patients, 13 experienced cancer recurrence after kidney transplantation. The mean delay in recurrence was 3 ± 2.3 years posttransplantation, and the cumulative incidences of recurrence were 7.7% at 5 years and 14.9% at 10 years. The risk of recurrence was higher in patients with clear cell RCC (13% vs 0%, P = 0.015). There was no correlation between posttransplant recurrence and the interval before transplantation. Factors associated with a higher risk of cancer recurrence were histological clear cell RCC (P = 0.025), tumor stage pT2 (P = 0.002), and Fuhrman grade IV (P < 0.001). Recurrences were associated with a high mortality rate; 76.9% of patients with recurrences had died by the end of the follow-up period.

CONCLUSIONS

Recurrences of clear cell RCC are not uncommon after kidney transplantation and are associated with very poor prognoses. These results should be considered before listing patients with a history of renal cancer for transplantation.

High-dimensional single-cell proteomics analysis identifies immune checkpoint signatures and therapeutic targets in ulcerative colitis

Immune checkpoints are regulators of immune cells and play key roles in the modulation of immune responses. The role of checkpoints in autoimmune disease is poorly understood but likely to be central since checkpoint inhibition during cancer treatment can cause autoimmunity. We generated a high-dimensional single-cell proteomics data set from PBMCs of healthy individuals and patients with ulcerative colitis (UC) by mass cytometry, enabling systems-wide analyses of immune cell frequencies and cell type-specific expression patterns of 12 immune checkpoints. Subtle but significant changes in immune cell frequencies and checkpoint expression were observed between UC patients on different treatment regimens and between patients and healthy controls. Most strikingly, UC patients showed a reduced number of peripheral NK-cells and those cells showed an altered phenotype including increased TIGIT expression. Based on these results, we modulated NK-cell function ex vivo through targeting of TIGIT pathway members. In summary, we describe a pattern of changes in immune cell abundance and checkpoint expression as a basis for UC patient stratification and we show modulation of a corresponding immune cell subset through checkpoint targeting. Our approach can be used for the identification of pathogenic immune cell subsets and guide target selection in autoimmunity and chronic inflammation.

Induction of Tolerance Towards Solid Organ Allografts Using Hematopoietic Cell Transplantation in Large Animal Models

Background

The application of hematopoietic cell transplantation for induction of immune tolerance has been limited by toxicities associated with conditioning regimens and to graft-versus-host disease (GVHD). Decades of animal studies have culminated into sufficient control of these two problems, making immune tolerance a viable alternative to life-long application of immunosuppressive drugs to prevent allograft rejection.

Methods

Studies in mice have paved the way for the application of HCT with limited toxicity in large animal models. Resultant studies in the pig, dog, and ultimately the nonhuman primate have led to appropriate methods for achieving nonmyeloablative irradiation protocols, dose, and timing of post-grafting immunosuppressive drugs, monoclonal antibody therapy, and biologicals for costimulatory molecule blockade. The genetics field has been extensively evaluated in appreciation of the ultimate need to obtain organs from MHC-mismatched unrelated donors.

Results

Nonmyeloablative conditioning regimens have been shown to be successful in inducing immune tolerance across all three animal models. Postgrafting immunosuppression is also important in assuring sustained donor hematopoiesis for tolerance. Donor chimerism need not be permanent to establish stable engraftment of donor organs, thereby essentially eliminating the risk of GVHD. Using nonmyeloablative HCT with monoclonal antibody immunosuppression, the kidney has been successfully transplanted in MHC-mismatched nonhuman primates.

Conclusions

Nonmyeloablative HCT for the establishment of temporary mixed chimerism has led to the establishment of stable tolerance against solid organ allografts in large animal models. The kidney, considered a tolerogenic organ, has been successfully transplanted in the clinic. Other organs such as heart, lung, and vascularized composite allografts (face and hands), remain distant possibilities. Further study in large animal models will be required to improve tolerance against these organs before success can be attained in the clinic.

Ex vivo expanded natural regulatory T cells from patients with end-stage renal disease or kidney transplantation are useful for autologous cell therapy

Novel concepts employing autologous, ex vivo expanded natural regulatory T cells (nTreg) for adoptive transfer has potential to prevent organ rejection after kidney transplantation. However, the impact of dialysis and maintenance immunosuppression on the nTreg phenotype and peripheral survival is not well understood, but essential when assessing patient eligibility. The current study investigates regulatory T-cells in dialysis and kidney transplanted patients and the feasibility of generating a clinically useful nTreg product from these patients. Heparinized blood from 200 individuals including healthy controls, dialysis patients with end stage renal disease and patients 1, 5, 10, 15, 20 years after kidney transplantation were analyzed. Differentiation and maturation of nTregs were studied by flow cytometry in order to compare dialysis patients and kidney transplanted patients under maintenance immunosuppression to healthy controls. CD127 expressing CD4⁺CD25^highFoxP3⁺ nTregs were detectable at increased frequencies in dialysis patients with no negative impact on the nTreg end product quality and therapeutic usefulness of the ex vivo expanded nTregs. Further, despite that immunosuppression mildly altered nTreg maturation, neither dialysis nor pharmacological immunosuppression or previous acute rejection episodes impeded nTreg survival in vivo. Accordingly, the generation of autologous, highly pure nTreg products is feasible and qualifies patients awaiting or having received allogenic kidney transplantation for adoptive nTreg therapy. Thus, our novel treatment approach may enable us to reduce the incidence of organ rejection and reduce the need of long-term immunosuppression.

Successful multidisciplinary treatment of uterine serous carcinoma in a patient who had previously undergone renal transplantation

OBJECTIVE

Renal transplantation is a risk factor for premalignant and malignant changes of the endometrium. Thus, prompt and aggressive treatment of postoperative complications remains a major issue. We report the case of an asymptomatic postmenopausal woman with a history of renal transplantation who underwent surgery for uterine serous carcinoma (USC).

CASE REPORT

An asymptomatic 59-year-old woman who had undergone renal transplantation presented with elevated serum CA-125 levels. Cancer screening revealed uterine serous carcinoma, for which she underwent total hysterectomy and bilateral salpingo-oophorectomy. Unfortunately, the postoperative course was complicated by cardiogenic shock and decompensated heart failure. The complexities of the cardiac problems and renal transplantation required a multidisciplinary approach involving different specialists. She was successfully discharged 48 days after the surgery.

CONCLUSION

Gynecologic cancer screening in asymptomatic postmenopausal women after renal transplantation is warranted. If postoperative complications occur in this population, a multidisciplinary approach is recommended.

Importance of Timed and Detailed Evaluation of Kidney Transplantation Candidates

Kidney transplant recipients are at increased risk of cardiovascular morbidity and malignant neoplasm, and meticulous evaluation of potential recipients is needed to minimize risks of complications after transplantation. The purpose of this study was to analyze the results of preoperative assessments and document the importance of timed and detailed examinations.

METHODS

Medical records of patients evaluated as kidney transplant candidates from January 2015 to September 2017 were retrospectively collected and analyzed.

RESULTS

Of the 216 patients evaluated during the study period, 135 (62.5%) were male, 112 (51.9%) had diabetes mellitus, 163 (75.5%) had hypertension, 31 (14.4%) had a cardiovascular event history, and 7 (3.2%) had previous history of malignant neoplasms. Mean (SD) patient age was 50.7 (10.8) years. All 216 recipient candidates underwent echocardiography. Mean (SD) ejection fraction was 57.8% (5.9%), and 48 candidates (22.2%) showed regional wall motional abnormality. Coronary angiography was performed on 81 candidates, and in 57 (70.4%) of these, coronary artery disease was detected. Malignant neoplasms were detected in 10 (4.6%) candidates. Kidney transplantation was performed on 55 candidates. One recipient died of Pneumocystis jirovecii pneumonia at 15 months after kidney transplant, but there was no death-censored graft failure, newly detected malignant neoplasm, or cardiovascular event over a mean (SD) follow-up duration of 15.5 (8.6) months.

CONCLUSION

Evaluation of kidney transplant candidates resulted in diagnoses of malignant neoplasms in 4.6% of patients and coronary artery disease in 26.4% of patients. The results of this study demonstrate candidates for kidney transplant should undergo detailed preoperative evaluation.

Occurrence and regression of BK polyomavirus associated carcinoma: a clinical and next-generation sequencing study

Low-level BK polyomavirus (BKPyV) shedding is seen in at least 10% of seropositive immunocompetent adults. Moreover, BKPyV infection is highly prevalent amongst immunocompromised populations, yet little is known on its relationship with malignancy. We studied a female patient with BKPyV-associated and donor-derived de novo high-grade sarcomatoid urothelial carcinoma developed 8 years after kidney transplantation from a male donor. Through whole-genome sequencing, we discovered integration of genotype IV BKPyV genome into the non-coding RNA (ncRNA) intronic region of human chromosome 18. The two breakpoints in the virus genome were located at the non-coding control region (NCCR) and large T antigen (TAg) coding region, respectively. Nevertheless, the TAg was overexpressed. We, therefore, inferred that the BKPyV was clonally integrated into the human genome in the form of concatemers, facilitating the expression of the TAg. The patient presented with multiorgan metastases, which were reduced in size and number throughout the body after removal of the graft and cessation of immunosuppressants. The few remaining lesions located in the liver were identified, through biopsy to be necrotic tumor tissue with TAg detected; additionally, genomic sequencing of the liver mass found Y chromosome. In conclusion, we propose that integration of the BKPyV genome is closely related to oncogenesis in this patient; while oncogenesis occurred when host immunity was impaired, recovery of the patient's native immunity effectively curbed viral replication and eliminated the metastatic lesions.

Immune-checkpoint inhibitors to treat cancers in specific immunocompromised populations: a critical review

INTRODUCTION

Because of their efficacy against numerous cancers, immune-checkpoint inhibitors (ICIs), anti-cytotoxic T-lymphocyte antigen-4, and anti-programmed cell death monoclonal antibodies are being used ever more often in oncology. However, some patients were excluded from clinical trials because of their comorbidities despite their potentially higher cancer frequencies, as is the case for immunocompromised patients. Areas covered: We analyzed reported preclinical and clinical information and evaluated the risk/benefit ratio for four immunocompromised populations: people living with human immunodeficiency virus (PLHs), solid-organ transplant recipients, recipients of hematopoietic stem-cell allografts, and patients with autoimmune diseases. Expert commentary: Information available in the literature is fragmentary and scarce, making it difficult to evaluate the risk/benefit ratio. It can, nonetheless, be noted that ICI use in PLHs seems possible. For solid-organ transplant recipients, the risk for the graft seems elevated. For the other two populations, it is difficult to conclude at this time.

Considerations for Pharmacoepidemiological Studies of Drug-Cancer Associations

In this MiniReview, we provide general considerations for the planning and conduct of pharmacoepidemiological studies of associations between drug use and cancer development. We address data sources, study design, assessment of drug exposure, ascertainment of cancer outcomes, confounder adjustment and future perspectives. Aspects of data sources include assessment of complete history of drug use and data on dose and duration of drug use, allowing estimates of cumulative exposure. Outcome data from formal cancer registries are preferable, but cancer data from other sources, for example, patient or pathology registries, medical records or claims are also suitable. The two principal designs for observational studies evaluating drug-cancer associations are the cohort and case-control designs. A key challenge in studies of drug-cancer associations is the exposure assessment due to the typically long period of cancer development. We present methods to examine early and late effects of drug use on cancer development and discuss the need for employing 'lag-time' in order to avoid reverse causation. We emphasize that a new-user study design should always be considered. We also underline the need for 'dose-response' analyses, as drug-cancer associations are likely to be dose-dependent. Generally, studies of drug-cancer associations should explore risk of site-specific cancer, rather than cancer overall. Additional differentiation may also be crucial for organ-specific cancer with various distinct histological subtypes (e.g., lung or ovary cancer). We also highlight the influence of confounding factors and discuss various methods to address confounding, while emphasizing that the choices of methods depend on the design and specific objectives of the individual study. In some studies, use of active comparator(s) may be preferable. Pharmacoepidemiological studies of drug-cancer associations are expected to evolve considerably in the coming years, due to the increasing availability of long-term data on drug exposures and cancer outcomes, the increasing conduct of multinational studies, allowing studies of rare cancers and subtypes of cancer, and methodological improvements specifically addressing cancer and other long-term outcomes.

Survival in children requiring chronic renal replacement therapy

Survival in the pediatric end-stage renal disease (ESRD) population has improved substantially over recent decades. Nonetheless, mortality remains at least 30 times higher than that of healthy peers. Patient survival is multifactorial and dependent on various patient and treatment characteristics and degree of economic welfare of the country in which a patient is treated. In this educational review, we aim to delineate current evidence regarding mortality risk in the pediatric ESRD population and provide pediatric nephrologists with up-to-date information required to counsel affected families.

Squamous Cell Carcinoma of Skin after 20 Years of Renal Transplantation

Solid organ transplant recipients are at high risk of developing malignancies due to the prolonged use of immunosuppressant drugs. Squamous cell carcinoma of skin can occur in these patients even after decades of organ transplant. A 45-year-old male underwent renal transplant for end-stage renal disease 23 years ago and was on immunosuppressive drugs since then. The patient was on regular follow-up. Three years back, he developed squamous cell carcinoma of both forearms and hands, which was treated with radiation therapy using 8 MeV electrons, by parallel opposed fields to a dose of 60 Gy/30 fractions. Complete response to treatment was achieved at 3 months posttreatment. The patient is currently on follow-up and asymptomatic for skin lesions. Hence, these patients require longer follow-up, active surveillance, and screening for early diagnosis and prompt treatment of the premalignant and malignant conditions.

Treatment options and predictive factors for recurrence and cancer-specific mortality in bladder cancer after renal transplantation: A multi-institutional analysis

OBJECTIVES

Bladder cancer (BC) in the transplanted population can represent a challenge owing to the immunosuppressed state of patients and the higher rate of comorbidities. The objective was to analyze the treatment of BC after renal transplant (RT), focusing on the mode of presentation, diagnosis, treatment options and predictive factors for recurrence.

MATERIAL AND METHODS

We conducted an observational prospective study with a retrospective analysis of 88 patients with BC after RT at 10 European centers. Clinical and oncologic data were collected, and indications and results of adjuvant treatment reviewed. The Kaplan-Meier method and uni- and multivariate Cox regression analyses were performed.

RESULTS

A total of 10,000 RTs were performed. Diagnosis of BC occurred at a median of 73 months after RT. Median follow-up was 126 months. Seventy-one patients (81.6%) had non-muscle invasive bladder cancer, of whom 29 (40.8%) received adjuvant treatment; of these, six (20.6%) received bacillus Calmette-Guérin and 20 (68.9%) mitomycin C. At univariate analysis, patients who received bacillus Calmette-Guérin had a significantly lower recurrence rate (P=.043). At multivariate analysis, a switch from immunosuppression to mTOR inhibitors significantly reduced the risk of recurrence (HR 0.24, 95% CI: 0.053-0.997, P=.049) while presence of multiple tumors increased it (HR 6.31, 95% CI: 1.78-22.3, P=.004). Globally, 26 patients (29.88%) underwent cystectomy. No major complications were recorded. Overall mortality (OM) was 32.2% (28 patients); the cancer-specific mortality was 13.8%.

CONCLUSIONS

Adjuvant bacillus Calmette-Guérin significantly reduces the risk of recurrence, as does switch to mTOR inhibitors. Multiple tumors increase the risk.

Clinical Translation of Mesenchymal Stromal Cell Therapies in Nephrology

Mesenchymal stromal cells have emerged as potential candidates for cell-based therapies to modulate the immune response in organ transplantation and repair tissues after acute or chronic injury. Preclinical studies have shown convincingly in rodent models that mesenchymal stromal cells can prolong solid organ graft survival and that they can induce immune tolerance, accelerate recovery from AKI, and promote functional improvement in chronic nephropathies. Multiple complex properties of the cells, including immunomodulatory, anti-inflammatory, and proregenerative effects, seem to contribute. The promising preclinical studies have encouraged investigators to explore the safety, tolerability, and efficacy of mesenchymal stromal cell-based therapy in pilot clinical trials, including those for bone marrow and solid organ transplantation, autoimmune diseases, and tissue and organ repair. Here, we review the available data on culture-expanded mesenchymal stromal cells tested in renal transplantation, AKI, and CKD. We also briefly discuss the relevant issues that must be addressed to ensure rigorous assessment of the safety and efficacy of mesenchymal stromal cell therapies to allow the translation of this research into the practice of clinical nephrology.

Chemotherapy and Transplantation: The Role of Immunosuppression in Malignancy and a Review of Antineoplastic Agents in Solid Organ Transplant Recipients

It is estimated that solid organ transplant recipients have a two- to fourfold greater overall risk of malignancy than the general population. Some of the most common malignancies after transplant include skin cancers and posttransplant lymphoproliferative disorder. In addition to known risk factors such as environmental exposures, genetics, and infection with oncogenic viruses, immunosuppression plays a large role in the development of cancer through the loss of the immunosurveillance process. The purpose of this article is to explain the role of immunosuppression in cancer and to review the classes of chemotherapeutics. The field of anticancer drugs is continually expanding and developing, with limited data on use in transplant recipients. This article aims to provide information on class review, adverse effects, dose adjustments, and drug interactions that are pertinent to the care of transplant recipients.

Gastrointestinal Pathologies in Patients After Successful Renal Transplantation-A Pilot Study

BACKGROUND

The beneficial effect of kidney transplantation in patients requiring continuous renal replacement therapy owing to chronic kidney disease is well known and accepted. Kidney transplantation protects the patient from complications that may develop during chronic dialysis. Unfortunately, there is also evidence that kidney transplant patients are more prone to developing cancer than healthy persons. The aim of this study was to evaluate the prevalence of gastrointestinal pathologies in patients after kidney transplantation.

METHODS

Adult patients after kidney transplantation, who are under the care of the Outpatient Department of Nephrology in Gdańsk, received alarm symptom questionnaires and referral for testing for the presence of fecal occult blood. Then, in 45 selected patients (29 men and 16 women) endoscopic examination was performed. Mean age was 57.6 ± 10.1 (range, 35-83) years.

RESULTS

Out of ∼940 patients after kidney transplantation, resting under supervision of outpatient department, 181 patients completed the questionnaire and 100 gave a stool sample for testing: 32 results were positive. After analyzing the questionnaires and stool results, 88 patients were qualified for further investigation. The endoscopic examination had been performed so far in 45 patients and revealed gastritis and/or duodenitis in 33 patients, diverticular colon disease in 18, esophagitis in 8, colon polyps in 14, stomach polyps in 3, inflammatory bowel disease in 7, and cancers in 3.

CONCLUSIONS

The preliminary results indicate that patients after kidney transplantation have significant risk of gastrointestinal pathologies and require detailed diagnostic endoscopy.

Modification of immunosuppressive therapy as risk factor for complications after liver transplantation

Management of complications post-liver transplantation (LT) includes immunosuppressive manipulations with the aim to reduce the overall burden of immunologic suppression and compensate for renal, cardiovascular, metabolic toxicities, and for the increased oncologic risk. Two approaches can be implemented to reduce immunosuppression-related adverse events: upfront schedules tailored to the pretransplant individual patient's risk profile versus downstream modifications in the event of immunosuppression-related complications. Upfront strategies are supported by evidence originating from prospective randomized trials and consist of triple/quadruple schedules whereby calcineurin inhibitors (CNI)-exposure is reduced with combination of anti-CD25 monoclonal antibodies, antimetabolites and corticosteroids. Quadruple regimens allow for staggering of CNI introduction and higher renal function in the early term, but their superiority in the long term has not yet been established. A more recent upfront schedule contemplates early (4 weeks) introduction of mammalian target of rapamycin inhibitor (mTORi) everolimus and allows for reduction of CNI up to 4 years posttransplantation. Incorporation of mTORi has the potential to prolong time to recurrence for patients with hepatocellular carcinoma. However, as suggested by the available evidence, downstream immunosuppressive manipulations are more frequently adopted in clinical practice. These encompass CNI replacement and immunosuppression withdrawal. Switching CNI to mTORi monotherapy is the option most commonly adopted to relieve renal function and compensate for posttransplant malignancies. Its impact is dependent on interval from transplantation and underlying severity of renal impairment. Introduction of mTORi is associated with longer overall survival for patients with extrahepatic posttransplant malignancies, but results are awaited for recurrences of hepatocellular carcinoma. Immunosuppression withdrawal seems feasible (70%) in very long term survivors (>10 years), but is not associated with reversal of immunosuppression-related complications. Awaiting novel immunosuppressive drug categories, integration of upfront strategies with the aim to reduce CNI-exposure and a low threshold for adjustment in the posttransplant course are both advisable to improve long-term outcomes of LT.

Everolimus and Malignancy after Solid Organ Transplantation: A Clinical Update

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