Cancer in kidney transplant recipients

Elucidating the nexus between onco-immunology and kidney transplantation: An insight from precision medicine perspective

The interplay of onco-immunology and kidney transplantation heralds a transformative era in medical science. This integration, while promising, presents significant challenges. Chief among these is the dichotomy of immunosuppression-boosting immunity against malignancies while suppressing it for graft survival. Additionally, limited clinical data on novel therapies, genetic variations influencing responses, economic concerns, and the narrow therapeutic window for post-transplant malignancies necessitate strategic addressal. Conversely, opportunities abound, including personalized immune monitoring, targeted therapies, minimized immunosuppression, and improved patient quality of life. Emphasizing collaborative research and interdisciplinary cooperation, the merging of these fields offers the potential for enhanced graft survival and reduced post-transplant malignancy risks. As we harness modern technology and promote patient-centric care, the vision for the future of kidney transplantation becomes increasingly hopeful, paving the way for more personalized and effective treatments. The article aims to elucidate the critical challenge of balancing immunosuppression to simultaneously combat malignancies and ensure graft survival. It addresses the scarcity of clinical data on novel therapies, the impact of genetic variations on treatment responses, and the economic and therapeutic concerns in managing post-transplant malignancies. Furthermore, it explores the opportunities precision medicine offers, such as personalized immune monitoring, targeted therapies, and reduced immunosuppression, which could significantly improve patient outcomes. Highlighting the importance of collaborative research and interdisciplinary efforts, the article seeks to demonstrate the potential for enhanced graft survival and reduced post-transplant malignancy risks. By leveraging modern technology and prioritizing patient-centric care, it envisions a future where kidney transplantation is more personalized and effective, offering hope for advancements in this field.

Incidence and clearance of cervical and anal high-risk human papillomavirus in kidney transplant recipients: Results from a Danish prospective clinical study

This study investigates the incidence and clearance of cervical and anal high-risk human papillomavirus (hrHPV) infection in kidney transplant recipients (KTRs) compared to immunocompetent controls. During 2016-2017, we enrolled 125 female KTRs and 125 female controls. Liquid-based cervical and anal cytology samples collected at enrollment and follow-up were tested for human papillomavirus (HPV) DNA using the CLART HPV2 test. All participants answered a questionnaire on lifestyle and sexual behavior at both examinations. KTRs had an increased age-adjusted risk of incident cervical hrHPV infection compared to controls (hazard ratio [HR] = 3.6, 95% CI = 1.2-11.2). Probability of cervical hrHPV clearance at 18 months was lower among KTRs (8.3%) than controls (66.7%). There was no statistically significant difference in anal hrHPV incidence between KTRs and controls (HR = 0.9, 95% CI = 0.4-2.0). Clearance of anal hrHPV was similar between KTRs and controls at 18 months. During the total follow-up, a lower anal hrHPV clearance, although not statistically significant, was observed among KTRs (HR = 0.3, 95% CI = 0.06-1.2). KTRs had higher incidence of cervical hrHPV and lower probability of clearance, especially of cervical hrHPV infections, than controls. Our findings support that KTRs are at increased risk of HPV infection and point to the need for targeted HPV prevention strategies, such as cervical cancer screening.

Homoharringtonine promotes heart allograft acceptance by enhancing regulatory T cells induction in a mouse model

BACKGROUND

Homoharringtonine (HHT) is an effective anti-inflammatory, anti-viral, and anti-tumor protein synthesis inhibitor that has been applied clinically. Here, we explored the therapeutic effects of HHT in a mouse heart transplant model.

METHODS

Healthy C57BL/6 mice were used to observe the toxicity of HHT in the liver, kidney, and hematology. A mouse heart transplantation model was constructed, and the potential mechanism of HHT prolonging allograft survival was evaluated using Kaplan-Meier analysis, immunostaining, and bulk RNA sequencing analysis. The HHT-T cell crosstalk was modeled ex vivo to further verify the molecular mechanism of HHT-induced regulatory T cells (Tregs) differentiation.

RESULTS

HHT inhibited the activation and proliferation of T cells and promoted their apoptosis ex vivo . Treatment of 0.5 mg/kg HHT for 10 days significantly prolonged the mean graft survival time of the allografts from 7 days to 48 days ( P <0.001) without non-immune toxicity. The allografts had long-term survival after continuous HHT treatment for 28 days. HHT significantly reduced lymphocyte infiltration in the graft, and interferon-γ-secreting CD4 + and CD8 + T cells in the spleen ( P <0.01). HHT significantly increased the number of peripheral Tregs (about 20%, P <0.001) and serum interleukin (IL)-10 levels. HHT downregulated the expression of T cell receptor (TCR) signaling pathway-related genes ( CD4 , H2-Eb1 , TRAT1 , and CD74 ) and upregulated the expression of IL-10 and transforming growth factor (TGF)-β pathway-related genes and Treg signature genes ( CTLA4 , Foxp3 , CD74 , and ICOS ). HHT increased CD4 + Foxp3 + cells and Foxp3 expression ex vivo , and it enhanced the inhibitory function of inducible Tregs.

CONCLUSIONS

HHT promotes Treg cell differentiation and enhances Treg suppressive function by attenuating the TCR signaling pathway and upregulating the expression of Treg signature genes and IL-10 levels, thereby promoting mouse heart allograft acceptance. These findings may have therapeutic implications for organ transplant recipients, particularly those with viral infections and malignancies, which require a more suitable anti-rejection medication.

Immunosuppression and cancer risk in kidney transplant recipients: A retrospective cohort study

We assessed whether contemporary immunosuppression agents were associated with cancer among kidney transplant recipients (KTR), and if this association varied by age and sex. We studied a retrospective province-wide cohort of primary KTR (1997-2016). Employing multivariable Cox models, we estimated associations of cumulative doses of prednisone, mycophenolate and tacrolimus administered over the past 10 years, lagged by 2 years, with the incidence of primary malignant neoplasms (PMN). We assessed interactions with age and sex. To assess the impact of exposure recency, we used weighted cumulative exposure (WCE) modeling. Among 1064 KTR, 108 (10.2%) developed PMN over median follow-up of 73 months (interquartile range: 32-120). Adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) of 0.96 (0.64-1.43), 1.34 (0.96-1.86), and 1.06 (0.88-1.29) were estimated for cumulative daily doses of prednisone (5 mg), mycophenolate (1000 mg), and tacrolimus (2 mg) administered continuously over the past 10 years, respectively. PMN risk associated with cumulative tacrolimus exposure was modified by age (interaction p = .035) and was more pronounced in 15-year and 30-year-old KTR (aHRs of 1.57 [1.08-2.28] and 1.31 [1.03-1.66], respectively) in comparison to older KTR. PMN risk increase associated with higher cumulative mycophenolate dose was more pronounced in females (aHR = 1.86 [1.15-3.00]) than in males (aHR = 1.16 [0.74-1.81]; interaction p = .131). WCE analyses suggested increased PMN risk the higher the mycophenolate doses taken 5-10 years ago. A trend toward increased PMN risk with long-term mycophenolate exposure, particularly in females, and more pronounced risk with long-term tacrolimus exposure in younger KTR, identify opportunities for tailored immunosuppression to mitigate cancer risk.

Late Treatment With Autologous Expanded Regulatory T-cell Therapy After Alemtuzumab Induction Is Safe and Facilitates Immunosuppression Minimization in Living Donor Renal Transplantation

BACKGROUND

The TWO Study (Transplantation Without Overimmunosuppression) aimed to investigate a novel approach to regulatory T-cell (Treg) therapy in renal transplant patients, using a delayed infusion protocol at 6 mo posttransplant to promote a Treg-skewed lymphocyte repopulation after alemtuzumab induction. We hypothesized that this would allow safe weaning of immunosuppression to tacrolimus alone. The COVID-19 pandemic led to the suspension of alemtuzumab use, and therefore, we report the unique cohort of 7 patients who underwent the original randomized controlled trial protocol. This study presents a unique insight into Treg therapy combined with alemtuzumab and is therefore an important proof of concept for studies in other diseases that are considering lymphodepletion.

METHODS

Living donor kidney transplant recipients were randomized to receive autologous polyclonal Treg at week 26 posttransplantation, coupled with weaning doses of tacrolimus, (Treg therapy arm) or standard immunosuppression alone (tacrolimus and mycophenolate mofetil). Primary outcomes were patient survival and rejection-free survival.

RESULTS

Successful cell manufacturing and cryopreservation until the 6-mo infusion were achieved. Patient and transplant survival was 100%. Acute rejection-free survival was 100% in the Treg-treated group at 18 mo after transplantation. Although alemtuzumab caused a profound depletion of all lymphocytes, including Treg, after cell therapy infusion, there was a transient increase in peripheral Treg numbers.

CONCLUSIONS

The study establishes that delayed autologous Treg therapy is both feasible and safe, even 12 mo after cell production. The findings present a new treatment protocol for Treg therapy, potentially expanding its applications to other indications.

Prevalence of cervical human papillomavirus in kidney transplant recipients: A systematic review and meta-analysis

OBJECTIVE

This systematic review and meta-analysis aims to investigate the prevalence of cervical high-risk human papillomavirus (hrHPV) among kidney transplant recipients (KTRs) and, furthermore to compare it to that in immunocompetent controls.

METHODS

A systematic literature search was conducted in PubMed, EMBASE, and Cochrane Library databases from January 2000 to February 2023, to identify studies investigating the prevalence of cervical hrHPV in KTRs. Pooled cervical hrHPV prevalences, odds ratios (ORs) comparing KTRs to controls and corresponding confidence intervals (CIs) were estimated using random effects logistic regression models. Heterogeneity between studies was assessed through the I2 statistic, and the significance was evaluated by the Cochrane's Q test.

RESULTS

Altogether, 16 studies covering >1200 KTRs were included. The prevalence of cervical hrHPV in KTRs was 27.7% (95% CI 21.3-35.1) with substantial interstudy heterogeneity. Stratification indicated a higher prevalence in recent years (2019-2023) and in Asia (39% (95% CI 11.2-61.4)). The prevalence of HPV16 and HPV18 in KTRs was 8.0% (95% CI 3.9-15.9) and 1.7% (95% CI 0.8-3.7), respectively. Comparing hrHPV prevalence in KTRs and controls based on six studies including >500 KTRs and 1000 controls, the OR for hrHPV was 2.0 (95% CI 1.1-3.6).

CONCLUSIONS

This meta-analysis establishes an increased cervical hrHPV prevalence in KTRs compared to controls. The increased risk may be associated with immunosuppressive therapy post-transplantation. Further research is needed to explore the potential benefits of HPV vaccination, including potential revaccination strategies in KTRs.

Fine-tuning tumor- and allo-immunity: advances in the use of immune checkpoint inhibitors in kidney transplant recipients

Cancer is a common complication after kidney transplantation. Kidney transplant recipients (KTR) have a 2- to 4-fold higher risk of developing cancer compared to the general population and post-transplant malignancy is the third most common cause of death in KTR. Moreover, it is well known that certain cancer types are overrepresented after transplantation, especially non-melanoma skin cancer. Immune checkpoint inhibitors (ICI) have revolutionized the treatment of cancer, with remarkable survival benefit in a subgroup of patients. ICI are monoclonal antibodies that block the binding of specific co-inhibitory signaling molecules. Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4), programmed cell death protein 1 (PD-1), and its ligand programmed cell death ligand 1 (PD-L1) are the main targets of ICI. Solid organ transplant recipients (SOTR) have been excluded from clinical trials owing to concerns about tumor response, allo-immunity, and risk of transplant rejection. Indeed, graft rejection has been estimated as high as 48% and represents an emerging problem. The underlying mechanisms of organ rejection in the context of treatment with ICI are poorly understood. The search for restricted antitumoral responses without graft rejection is of paramount importance. This review summarizes the current knowledge of the use of ICI in KTR, the potential mechanisms involved in kidney graft rejection during ICI treatment, potential biomarkers of rejection, and how to deal with rejection in clinical practice.

Impact of Immunosenescence in Older Kidney Transplant Recipients: Associated Clinical Outcomes and Possible Risk Stratification for Immunosuppression Reduction

The number of older individuals receiving a kidney transplant as replacement therapy has significantly increased in the past decades and this increase is expected to continue. Older patients have a lower rate of acute rejection but an increased incidence of death with a functioning graft. Several factors, including an increased incidence of infections, post-transplant malignancy and cardiovascular comorbidity and mortality, contribute to this increased risk. Notwithstanding, kidney transplantation is still the best form of kidney replacement therapy in all patients with chronic kidney disease, including in older individuals. The best form of immunosuppression and the optimal dose of these medications in older recipients remains a topic of discussion. Pharmacological studies have usually excluded older patients and when included, patients were highly selected and their numbers insignificant to draw a reasonable conclusion. The reduced incidence of acute rejection in older recipients has largely been attributed to immunosenescence. Immunosenescence refers to the aging of the innate and adaptive immunity, accumulating in phenotypic and functional changes. These changes influences the response of the immune system to new challenges. In older individuals, immunosenescence is associated with increased susceptibility to infectious pathogens, a decreased response after vaccinations, increased risk of malignancies and cardiovascular morbidity and mortality. Chronic kidney disease is associated with premature immunosenescent changes, and these are independent of aging. The immunosenescent state is associated with low-grade sterile inflammation termed inflammaging. This chronic low-grade inflammation triggers a compensatory immunosuppressive state to avoid further tissue damage, leaving older individuals with chronic kidney disease in an immune-impaired state before kidney transplantation. Immunosuppression after transplantation may further enhance progression of this immunosenescent state. This review covers the role of immunosenescence in older kidney transplant recipients and it details present knowledge of the changes in chronic kidney disease and after transplantation. The impact of immunosuppression on the progression and complications of an immunosenescent state are discussed, and the future direction of a possible clinical implementation of immunosenescence to individualize/reduce immunosuppression in older recipients is laid out.

Cancer mortality after kidney transplantation: A multicenter cohort study in Italy

Kidney transplant (KT) recipients are known to be at risk of developing several cancer types; however, cancer mortality in this population is underinvestigated. Our study aimed to assess the risk of cancer death among Italian KT recipients compared to the corresponding general population. A cohort study was conducted among 7373 individuals who underwent KT between 2003 and 2020 in 17 Italian centers. Date and cause of death were retrieved until 31 December 2020. Indirect standardization was used to estimate standardized mortality ratios (SMRs) and corresponding 95% confidence intervals (CIs). Cancer was the most common cause of death among the 7373 KT recipients, constituting 32.4% of all deaths. A 1.8-fold excess mortality (95% CI: 1.59-2.09) was observed for all cancers combined. Lymphomas (SMR = 6.17, 95% CI: 3.81-9.25), kidney cancer (SMR = 5.44, 95% CI: 2.97-8.88) and skin melanoma (SMR = 3.19, 95% CI: 1.03-6.98) showed the highest excess death risks. In addition, SMRs were increased about 1.6 to 3.0 times for cancers of lung, breast, bladder and other hematopoietic and lymphoid tissues. As compared to the general population, relative cancer mortality risk remained significantly elevated in all age groups though it decreased with increasing age. A linear temporal increase in SMR over time was documented for all cancers combined (P < .01). Our study documented significantly higher risks of cancer death in KT recipients than in the corresponding general population. Such results support further investigation into the prevention and early detection of cancer in KT recipients.

Incidence of De Novo Post-Transplant Malignancies in Thai Adult Kidney Transplant Recipients: A Single-Center, Population-Controlled, Retrospective Cohort Study at the Highest Volume Kidney Transplant Center in Thailand

Kidney transplant recipients (KTRs) are at increased risk of developing de novo post-transplant malignancies (PTMs), with regional differences in types with excess risk compared to the general population. A single-center, population-controlled, retrospective cohort study was conducted at a tertiary care center in Thailand among all adults who underwent their first kidney transplant from 1986 to 2018. Standardized incidence ratios (SIRs) of malignancy by age, sex, and place of residence were obtained using data from the National Cancer Registry of Thailand as population control. There were 2,024 KTRs [mean age, 42.4 years (SD 11.4); female patients, 38.6%] during 16,495 person-years at risk. Of these, 125 patients (6.2%) developed 133 de novo PTMs. The SIR for all PTMs was 3.85 (95% CI 3.22, 4.56), and for pooled solid and hematologic PTMs, it was 3.32 (95% CI 2.73, 3.99). Urothelial malignancies had the largest excess risk, especially in women [female SIR 114.7 (95% CI 66.8, 183.6); male SIR 17.5 (95% CI 8.72, 31.2)]. The next two most common cancers were non-Hodgkin's lymphoma and skin cancer [SIR 20.3 (95% CI 13.6, 29.1) and 24.7 (95% CI 15.3-37.8), respectively]. Future studies are needed to identify the risk factors and assess the need for systematic screening among PTMs with excess risk in KTRs.

Bronchiectasis in renal transplant patients: a cross-sectional study

BACKGROUND

Bronchiectasis is a chronic airway disease characterized by permanent and irreversible abnormal dilatation of bronchi. Several studies have reported the development of bronchiectasis after renal transplantation (RT), but no prospective study specifically assessed bronchiectasis in this population. This study aimed to compare features of patients with bronchiectasis associated with RT to those with idiopathic bronchiectasis.

METHODS

Nineteen patients with bronchiectasis associated with RT (RT-B group) and 23 patients with idiopathic bronchiectasis (IB group) were prospectively included in this monocentric cross-sectional study. All patients underwent clinical, functional, laboratory, and CT scan assessments. Sputum was collected from 25 patients (n = 11 with RT-B and n = 14 with IB) and airway microbiota was analyzed using an extended microbiological culture.

RESULTS

Dyspnea (≥ 2 on mMRC scale), number of exacerbations, pulmonary function tests, total bronchiectasis score, severity and prognosis scores (FACED and E-FACED), and quality of life scores (SGRQ and MOS SF-36) were similar in the RT-B and IB groups. By contrast, chronic cough was less frequent in the RT-B group than in the IB group (68% vs. 96%, p = 0.03). The prevalence and diversity of the airway microbiota in sputum were similar in the two groups.

CONCLUSION

Clinical, functional, thoracic CT scan, and microbiological characteristics of bronchiectasis are overall similar in patients with IB and RT-B. These results highlight that in RT patients, chronic respiratory symptoms and/or airway infections should lead to consider the diagnosis of bronchiectasis. Further studies are required to better characterize the pathophysiology of RT-B including airway microbiota, its incidence, and impact on therapeutic management.

Incidence of renal cell carcinoma after solid organ transplantation: a systematic review and meta-analysis

BACKGROUND

The incidence rate of malignant tumors after solid organ transplantation is higher than the normal population. The aim of our study is to identify the risk of renal cell carcinoma (RCC) after liver, kidney, heart and lung transplantation, respectively, and suggest that transplant patients can be screened early for tumors to avoid risk.

METHODS

PubMed, Embase and the Cochrane Library from their inception until August 16,2023. Retrospective and cohort studies which focus on the statistical data of standardized incidence ratios (SIRs) of RCC after solid organ transplantation (SOT) more than one year have been included and extracted. The study was registered with PROSPERO, CRD4202022343633.

RESULTS

Sixteen original studies have been included for meta-analysis. Liver transplantation could increase the risk of RCC (SIR = 0.73, 95%CI: 0.53 to 0.93) with no heterogeneity(P = 0.594, I2 = 0.0%). And kidney transplantation could increase the risk of RCC(8.54, 6.68 to 10.40; 0.000,90.0%). Besides, heart and lung transplantation also could increase the risk of RCC(SIR = 0.73, 95%CI: 0.53 to 0.93; SIR = 1.61, 95%CI:0.50 to 2.71). Moreover, significance could also be found in most subgroups, especially the European group and retrospective study group. What's more, after removing studies which have a greater impact on the overall outcome in RCC rate after kidney transplantation, heterogeneity did not solve and significant different was also observed in the European group (7.15, 5.49 to 8.81; 0.000, 78.6%).

CONCLUSION

Liver, kidney, heart and lung transplantation patients have an increased risk of processing RCC compared to the general population and most subgroups, especially in geographic location of European subgroup, which suggested that patients should be screened frequently after transplantation.

Effectiveness and safety of immunosuppressive regimens used as maintenance therapy in kidney transplantation: The CESIT study

Maintenance immunosuppressive therapy used in kidney transplantation typically involves calcineurin inhibitors, such as tacrolimus or cyclosporine, in combination with mycophenolate or mechanistic target of rapamycin (mTORi) with or without corticosteroids. An Italian retrospective multicentre observational study was conducted to investigate the risk-benefit profile of different immunosuppressive regimens. We identified all subjects who underwent kidney transplant between 2009 and 2019, using healthcare claims data. Patients on cyclosporine and tacrolimus-based therapies were matched 1:1 based on propensity score, and effectiveness and safety outcomes were compared using Cox models (HR; 95%CI). Analyses were also conducted comparing mTORi versus mycophenolate among tacrolimus-treated patients. Patients treated with cyclosporine had a higher risk of rejection or graft loss (HR:1.69; 95%CI:1.16-2.46) and a higher incidence of severe infections (1.25;1.00-1.55), but a lower risk of diabetes (0.66;0.47-0.91) compared to those treated with tacrolimus. Among tacrolimus users, mTORi showed non-inferiority to MMF in terms of mortality (1.01;0.68-1.62), reject/graft loss (0.61;0.36-1.04) and severe infections (0.76;0.56-1.03). In a real-life setting, tacrolimus-based immunosuppressive therapy appeared to be superior to cyclosporine in reducing rejection and severe infections, albeit with an associated increased risk of diabetes. The combination of tacrolimus and mTORi may represent a valid alternative to the combination with mycophenolate, although further studies are needed to confirm this finding.

Adoptive Immune Effector Cell Therapies in Cancer and Solid Organ Transplantation: A Review

Cancer is one of the most devastating complications of kidney transplantation and constitutes one of the leading causes of morbidity and mortality among solid organ transplantation (SOT) recipients. Immunosuppression, although effective in preventing allograft rejection, inherently inhibits immune surveillance against oncogenic viral infections and malignancy. Adoptive cell therapy, particularly immune effector cell therapy, has long been a modality of interest in both cancer and transplantation, though has only recently stepped into the spotlight with the development of virus-specific T-cell therapy and chimeric antigen receptor T-cell therapy. Although these modalities are best described in hematopoietic cell transplantation and hematologic malignancies, their potential application in the SOT setting may hold tremendous promise for those with limited therapeutic options. In this review, we provide a brief overview of the development of adoptive cell therapies with a focus on virus-specific T-cell therapy and chimeric antigen receptor T-cell therapy. We also describe the current experience of these therapies in the SOT setting as well as the challenges in their application and future directions in their development.

Epidemiology of Cancer in Kidney Transplant Recipients

Kidney transplantation is the ideal treatment modality for patients with end-stage kidney disease, with excellent outcomes post-transplant compared with dialysis. However, kidney transplant recipients are at increased risk of infections and cancer because of the need for immunosuppression. Kidney transplant recipients have approximately two to three times greater risk of developing cancer than the general population, and cancer is a major contributor to morbidity and mortality. Most of the increased risk is driven by viral-mediated cancers such as post-transplant lymphoproliferative disorder, anogenital cancers, and Kaposi sarcoma. Nonmelanoma skin cancer is the most frequent type of cancer in kidney transplant recipients, likely due to an interaction between ultraviolet radiation exposure and decreased immune surveillance. Occurrence of the more common types of solid organ cancers seen in the general population, such as breast, prostate, lung, and colorectal cancers, is not, or is only mildly, increased post-transplant. Clinical care and future research should focus on prevention and on improving outcomes for important immunosuppression-related malignancies, and treatment options for other cancers occurring in the transplant setting.

Access to Cancer Care: Prevention and Screening for Females Post Kidney Transplantation Around the World

Kidney transplantation offers recipients superior outcomes and improved quality of life compared with dialysis. However, the need for ongoing immunosuppression places recipients at increased risk of certain forms of cancer. Screening and early detection of precancerous lesions are one of the few proven ways to lower the risk of cancer morbidity and mortality in the transplant population. Women have additional barriers to cancer screening services globally, especially in low- and middle-income countries as well as within certain disadvantaged groups in high-income countries. There is a dearth of published data on screening guidelines and policies on post-transplant malignancy in female recipients. It is vital that health care providers and patients are educated regarding the risks of cancer at all post-transplant stages and that the recommended screening policies are adhered to in order to reduce associated morbidity and mortality in this at-risk group.

Patient-Centered Research and Outcomes in Cancer and Kidney Transplantation

Cancer has been identified by kidney transplant recipients as a critically important outcome. The co-occurrence of cancer and kidney transplantation represents a complex intersection of diseases, symptoms, and competing priorities for treatments. Research that focuses on biochemical parameters and clinical events may not capture the priorities of patients. Patient-centered research can improve the relevance and efficiency of research and is particularly pertinent in the setting of cancer and kidney transplantation to facilitate shared decision-making in complex clinical situations. In addition, patient-reported outcomes can facilitate the assessment of patients' experiences, symptom burden, treatment side effects, and quality of life. This review discusses patient-centered research in the context of kidney transplantation and cancer, including consumer involvement in research and patient-centered outcomes and their measures and inclusion in core outcome sets.

Renal Cell Carcinoma in End-Stage Kidney Disease and the Role of Transplantation

Kidney transplant patients have a higher risk of renal cell carcinoma (RCC) compared to non-transplanted end-stage kidney disease (ESKD) patients. This increased risk has largely been associated with the use of immunosuppression; however, recent genetic research highlights the significance of tissue specificity in cancer driver genes. The implication of tissue specificity becomes more obscure when addressing transplant patients, as two distinct metabolic environments are present within one individual. The oncogenic potential of donor renal tissue is largely unknown but assumed to pose minimal risk to the kidney transplant recipient (KTR). Our review challenges this notion by examining how donor and recipient microenvironments impact a transplant recipient's associated risk of renal cell carcinoma. In doing so, we attempt to encapsulate how ESKD-RCC and KTR-RCC differ in their incidence, pathogenesis, outcome, and approach to management.

RapaLink-1 outperforms rapamycin in alleviating allogeneic graft rejection by inhibiting the mTORC1-4E-BP1 pathway in mice

Inhibition of mammalian target of rapamycin (mTOR), which is a component of both mTORC1 and mTORC2, leads to clinical benefits for organ transplant recipients. Pathways to inhibit mTOR include strengthening the association of FKBP12-mTOR or competing with ATP at the active site of mTOR, which have been applied to the design of first- and second-generation mTOR inhibitors, respectively. However, the clinical efficacy of these mTOR inhibitors may be limited by side effects, compensatory activation of kinases and attenuation of feedback inhibition of receptor expression. A new generation of mTOR inhibitors possess a core structure similar to rapamycin and covalently link to mTOR kinase inhibitors, resulting in moderate selectivity and potent inhibition of mTORC1. Since the immunosuppressive potential of this class of compounds remains unknown, our goal is to examine the therapeutic efficacy of a third-generation mTOR inhibitor in organ transplantation. In this study, RapaLink-1 outperformed rapamycin in inhibiting T-cell proliferation and significantly prolonged graft survival time. Mechanistically, the ameliorated rejection induced by RapaLink-1 is associated with a reduction in p-4E-BP1 in T cells, resulting in an elevation in Treg cells alongside a decline in Th1 and Th17 cells. For the first time, these studies demonstrate the effectiveness of third-generation mTOR inhibitors in inhibiting allograft rejection, highlighting the potential of this novel class of mTOR inhibitors for further investigation.

Prior cancer history and suitability for kidney transplantation

Kidney transplantation is the optimal treatment for most patients with kidney failure. For patients with a prior history of treated cancers, listing and transplant eligibility decisions are complex. Patients and health professionals are obliged to consider the time-periods between cancer cure and transplantation, the risk of cancer recurrence under the influence of immunosuppression and anti-cancer treatment options if the disease recurs. Cancer recurrence is associated with a high mortality rate, thus potentially reduces the projected survival benefit of transplantation, and dampens the utility of scarce organs. In view of the uncertain risk of harms, clinicians may consider transplantation for candidates with prior cancer history only after an extended period of cancer-free interval, as the fear of disease recurrence and shortened life expectancy may outweigh the benefits of receiving a kidney transplant compared with dialysis. Over the past decade, the evolution of novel anti-cancer therapies coupled with improved understanding of cancer genomics have led to considerable improvement in cancer-free survival. It is therefore justifiable to make individualized transplant suitability decisions based the joint effects of cancer biology, available therapeutic options and prognostic covariates on clinical outcomes. In this review, we first summarized the cancer epidemiology in kidney transplant recipients. We then explored how the probability of cancer cure, risk of recurrence and outcomes in candidates with a prior cancer history may influence the decisions to transplant. Finally, the role of shared decision-making between health professionals and patients regarding the optimal management options, and considerations of patients' preferences and values are discussed.

Müllerian-Type Clear Cell Carcinoma of Donor Origin in a Male Patient with a Kidney Transplant: Ascertained by Molecular Testing

Clear cell carcinomas of Müllerian origin have a strong female predominance and only extremely rarely will arise within the kidney, presumably due to ectopic Müllerian embryogenesis. Herein, we report a unique case of metastatic Müllerian type clear cell carcinoma in a 37-year-old patient who had previously received a transplanted kidney from his father at age 11 (due to severe bilateral vesicoureteral reflux) and remained on chronic immunosuppression. The tumor was highly aggressive and demonstrated somatic mutations in NF2 and SETD2. Imaging of the transplanted kidney did not reveal any clear evidence of malignancy. However, targeted multigene sequencing and short tandem repeat testing revealed that the cancer was of donor origin, presumably from ectopic Müllerian tissue transplanted to the patient along with the kidney graft. The tumor was resistant to first-line therapy with a triple combination of carboplatin plus paclitaxel plus bevacizumab, as well as to second-line immunotherapy with nivolumab plus ipilimumab after tapering down the patient's immunosuppression. Despite the tumor being genetically distinct from the host, the use of immune checkpoint therapy with nivolumab plus ipilimumab did not yield a response. This unique case showcases the value of molecular testing in determining the tumor origin in patients with solid organ transplants who present with cancers of unknown primary. This can prompt the potential investigation of other recipients from the same donor.

Role of standard HLA mismatch in modifying associations between non-pharmacologic risk factors and solid organ malignancy after kidney transplantation

BACKGROUND

Human leukocyte antigen mismatch(es) (HLA-mm) between donors and recipients has not been extensively studied either as a risk factor for solid organ malignancy (SOM) or as a modifier of associations between nonpharmacologic risk factors and SOM in kidney transplant recipients (KTRs).

METHODS

In a secondary analysis from a previous study, 166,256 adult KTRs in 2000-2018 who survived the first 12 months post-transplant free of graft loss or malignancy were classified into 0, 1-3, and 4-6 standard HLA-mm cohorts. Multivariable cause-specific Cox regressions analyzed the risks of SOM and all-cause mortality (ac-mortality) in 5 years following the first KT year. Comparisons of associations between SOM and risk factors in HLA mismatch cohorts were made by estimating the ratios of adjusted hazard ratios.

RESULTS

Compared with 0 HLA-mm, 1-3 HLA-mm was not associated, and 4-6 HLA-mm was equivocally associated with increased risk of SOM [hazard ratio, (HR) = 1.05, 95%, confidence interval (CI) = 0.94-1.17 and HR = 1.11, 95% CI = 1.00-1.34, respectively]. Both 1-3 HLA-mm and 4-6 HLA-mm were associated with increased risk of ac-mortality compared with 0 HLA mm [hazard ratio (HR) = 1.12, 95%, Confidence Interval (CI) = 1.08-1.18) and (HR = 1.16, 95% CI = 1.09-1.22), respectively]. KTR's history of pre-transplant cancer, age 50-64, and >/=65 years were associated with increased risks of SOM and ac-mortality in all HLA mismatch cohorts. Pre-transplant dialysis >2 years, diabetes as the primary renal disease, and expanded or standard criteria deceased donor transplantation were risk factors for SOM in the 0 and 1-3 HLA-mm cohorts and of ac-mortality in all HLA-mm cohorts. KTRs male sex or history of previous kidney transplant was a risk factor for SOM in the 1-3 and 4-6 HLA-mm cohorts and of ac-mortality in all HLA-mm cohorts.

CONCLUSION

Direct association between SOM and the degree of HLA mismatching is equivocal and limited to the 4-6 HLA-mm stratum; however, the degree of HLA mismatching has significant modifying effects on the associations between specific nonpharmacologic risk factors and SOM in KTRs.

Temporal trends of de novo urological malignancy in renal transplant recipients without a cancer history: A longitudinal cohort study

BACKGROUND

The incidence of malignancies after successful kidney transplantation has historically been higher than in the general population, with adverse impact on clinical outcomes. However, uncertainty remains as to which cancers occur at what time points after kidney transplantation.

METHODS

We conducted a longitudinal cohort study to investigate the temporal trends and topographic patterns of de novo malignancies to optimize surveillance protocols and improve transplant outcome in renal transplant recipients. Measurement of death and cancer events was performed to calculate the cumulative risk of events of interest.

RESULTS

Between 2000 and 2013, 3169 renal transplant recipients were retrospectively screened; 3035 (96%) of them met eligibility criteria and were evaluated with a follow-up of 27612 person-years. There was suboptimal overall survival and malignancy-free survival in renal transplant recipients compared to reference groups (HR: 1.65; 95% CI: 1.50-1.82; p < .001; HR: 2.33; 95% CI: 2.04-2.66; p < .001, respectively). Among renal transplant recipients, urological malignancies were predominant (57.5%), followed by digestive tract malignancies (21.4%). The cancer risks of the urinary bladder and upper urinary tract were lower in male subjects (HR: .48; 95% CI: .33-.72; p < .001; HR: .34; 95% CI: .20-.59; p < .001, respectively). The temporal trends of urological malignancies among renal transplant recipients were expressed in a bimodal pattern, with M-shaped peaks at 3 and 9 years, with gender disparity.

CONCLUSIONS

In renal transplant recipients, cancer occurrences are shown as M-shaped twin peaks. Our study highlights that specific customized 'targeted' strategies for cancer surveillance programs are required to optimize posttransplant care.

Variations in Risk of Cancer and Death From Cancer According to Kidney Allograft Function, Graft Loss, and Return to Dialysis

BACKGROUND

Cancer incidence and mortality may change with varying kidney allograft function and after graft loss. We aimed to quantify cancer incidence and mortality during periods with a functioning graft and after graft loss.

METHODS

We included all adult Australians aged 20 and above who commenced kidney replacement therapy between 1982 and 2014 using data from Australia and New Zealand Dialysis and Transplant Registry. We calculated the standardized incidence ratios and standardized mortality ratios (standardized against the Australian general population) for dialysis patients and transplant recipients during periods with a functioning graft and after graft loss.

RESULTS

A total of 44 765 dialysis patients without transplants, 13 443 with first kidney transplants, 2951 after first graft loss, 1010 with second transplants, and 279 after second graft loss were followed for 274 660 patient-years. Cancer incidence and mortality (per 100 000 patient-years) were 1564 and 760 in dialysis patients, 1564 and 689 in recipients of first transplants, 1188 and 390 after first graft loss, 1525 and 693 after second transplants, and 1645 and 779 after second graft loss. Cancer standardized incidence ratios and standardized mortality ratios (95% confidence intervals) were 1.15 (1.11-1.20) and 1.29 (1.21-1.36) for dialysis patients, 2.03 (1.94-2.13) and 2.50 (2.33-2.69) for recipients following their first transplant, 1.55 (1.29-1.85) and 1.40 (1.00-1.90) after first graft loss, 2.18 (1.79-2.63) and 3.00 (2.23-3.96) for second transplants, 2.59 (1.56-4.04) and 3.82 (1.75-7.25) after second graft loss.

CONCLUSIONS

In kidney transplant recipients, cancer incidence and mortality are highest during periods with a functioning graft and remained higher than in the general population even after graft loss.

Machine learning does not outperform traditional statistical modelling for kidney allograft failure prediction

Machine learning (ML) models have recently shown potential for predicting kidney allograft outcomes. However, their ability to outperform traditional approaches remains poorly investigated. Therefore, using large cohorts of kidney transplant recipients from 14 centers worldwide, we developed ML-based prediction models for kidney allograft survival and compared their prediction performances to those achieved by a validated Cox-Based Prognostication System (CBPS). In a French derivation cohort of 4000 patients, candidate determinants of allograft failure including donor, recipient and transplant-related parameters were used as predictors to develop tree-based models (RSF, RSF-ERT, CIF), Support Vector Machine models (LK-SVM, AK-SVM) and a gradient boosting model (XGBoost). Models were externally validated with cohorts of 2214 patients from Europe, 1537 from North America, and 671 from South America. Among these 8422 kidney transplant recipients, 1081 (12.84%) lost their grafts after a median post-transplant follow-up time of 6.25 years (Inter Quartile Range 4.33-8.73). At seven years post-risk evaluation, the ML models achieved a C-index of 0.788 (95% bootstrap percentile confidence interval 0.736-0.833), 0.779 (0.724-0.825), 0.786 (0.735-0.832), 0.527 (0.456-0.602), 0.704 (0.648-0.759) and 0.767 (0.711-0.815) for RSF, RSF-ERT, CIF, LK-SVM, AK-SVM and XGBoost respectively, compared with 0.808 (0.792-0.829) for the CBPS. In validation cohorts, ML models' discrimination performances were in a similar range of those of the CBPS. Calibrations of the ML models were similar or less accurate than those of the CBPS. Thus, when using a transparent methodological pipeline in validated international cohorts, ML models, despite overall good performances, do not outperform a traditional CBPS in predicting kidney allograft failure. Hence, our current study supports the continued use of traditional statistical approaches for kidney graft prognostication.

Sebaceous carcinoma in solid organ transplant recipients: The elegant path from epidemiology to etiology

Sebaceous carcinoma (SC) is a rare skin cancer associated with rapid progression and relatively poor survival, particularly in solid organ transplant recipients (SOTRs). Immunosuppressive regimens place SOTRs at substantially increased risk of a variety of skin cancers; recent research has shown a 25-fold increase in SC in the SOTR population, especially among lung recipients, older males, those with longer time since transplant, and patients undergoing induction therapy with thymoglobulin. The potential etiologic mechanisms underlying SC are multifaceted and complex. Immunosuppression creates a microcosm through which to view causative factors for carcinogenesis which has implications in elucidating mechanistic etiologies for SC far beyond the SOTR population, since not all cancers are more common in immunosuppressed patients. Research integrating the role of oncogenic viruses, underlying medical conditions, genetic risk factors, toxicity of prophylactic medications, drug-induced photosensitization, and T-cell deficiency/dysfunction is needed to better elucidate the factors underlying SC in immunosuppressed hosts. In this report, we integrate current research regarding SC in SOTR patients using the causal pie/sufficient-component cause model. In doing so, we provide a paradigm through which to view future research regarding the etiology of SC.

P32: a sex- and gender-sensitive model for evidence-based precision medicine: from knowledge generation to implementation in the field of kidney transplantation

Precision medicine emerged as a promising approach to identify suitable interventions for individual patients with a particular health concern and at various time points. Technology can enable the acquisition of increasing volumes of clinical and "omics" data at the individual and population levels and support advanced clinical decision making. However, to keep pace with evolving societal realities and developments, it is important to systematically include sex- and gender-specific considerations in the research process, from the acquisition of knowledge to implementation. Building on the foundations of evidence-based medicine and existing precision medicine frameworks, we propose a novel evidence-based precision medicine framework in the form of the P3²model, which considers individual sex-related (predictive [P1], preventive [P2], and personalized [P3] medicine) and gender-related (participatory [P4], psychosocial [P5], and percipient [P6] medicine) domains and their intersection with ethnicity, geography, and other demographic and social variables, in addition to population, community, and public dimensions (population-informed [P7], partnered with community [P8], and public-engaging [P9] medicine, respectively). Through its ability to contextualize and reflect on societal realities and developments, our model is expected to promote consideration of diversity, equity, and inclusion principles and, thus, enrich science, increase reproducibility of research, and ensure its social impact.

Clonal dynamics of alloreactive T cells in kidney allograft rejection after anti-PD-1 therapy

Kidney transplant recipients are at particular risk for developing tumors, many of which are now routinely treated with immune checkpoint inhibitors (ICIs); however, ICI therapy can precipitate transplant rejection. Here, we use TCR sequencing to identify and track alloreactive T cells in a patient with melanoma who experienced kidney transplant rejection following PD-1 inhibition. The treatment was associated with a sharp increase in circulating alloreactive CD8+ T cell clones, which display a unique transcriptomic signature and were also detected in the rejected kidney but not at tumor sites. Longitudinal and cross-tissue TCR analyses indicate unintended expansion of alloreactive CD8+ T cells induced by ICI therapy for cancer, coinciding with ICI-associated organ rejection.

Metabolic determinants of tumour initiation

Tumours exhibit notable metabolic alterations compared with their corresponding normal tissue counterparts. These metabolic alterations can support anabolic growth, enable survival in hostile environments and regulate gene expression programmes that promote malignant progression. Whether these metabolic changes are selected for during malignant transformation or can themselves be drivers of tumour initiation is unclear. However, intriguingly, many of the major bottlenecks for tumour initiation - control of cell fate, survival and proliferation - are all amenable to metabolic regulation. In this article, we review evidence demonstrating a critical role for metabolic pathways in processes that support the earliest stages of tumour development. We discuss how cell-intrinsic factors, such as the cell of origin or transforming oncogene, and cell-extrinsic factors, such as local nutrient availability, promote or restrain tumour initiation. Deeper insight into how metabolic pathways control tumour initiation will improve our ability to design metabolic interventions to limit tumour incidence.

De novo upper tract urothelial carcinoma after renal transplantation: a single-center experience in China

BACKGROUND

Long-term prognosis and risk factors of de novo upper tract urothelial carcinoma after renal transplantation were rarely studied. Thus, the aim of this study was to investigate the clinical features, risk factors, and long-term prognosis of de novo upper tract urothelial carcinoma after renal transplantation, especially the impact of aristolochic acid on tumor, using a large sample.

METHODS

106 patients were enrolled in retrospective study. The endpoints included overall survival, cancer-specific survival, bladder or contralateral upper tract recurrence-free survival. Patients were grouped according to aristolochic acid exposure. Survival analysis was performed using Kaplan-Meier curve. Log-rank test was used to compare the difference. Multivariable cox regression was conducted to evaluate the prognostic significance.

RESULTS

Median time from transplantation to development of upper tract urothelial carcinoma was 91.5 months. Cancer-specific survival rate at 1, 5, 10 years was 89.2%, 73.2%, 61.6%. Tumor staging (≥ T2), lymph node status (N +) were independent risk factors for cancer-specific death. Contralateral upper tract recurrence-free survival rate at 1, 3, 5 years was 80.4%, 68.5%, 50.9%. Aristolochic acid exposure was independent risk factor for contralateral upper tract recurrence. The patients exposed to aristolochic acid had more multifocal tumors and higher incidence of contralateral upper tract recurrence.

CONCLUSION

Both higher tumor staging and positive lymph node status were associated with a worse cancer-specific survival in patients with post-transplant de novo upper tract urothelial carcinoma, which highlighted the importance of early diagnosis. Aristolochic acid was associated with multifocality of tumors and higher incidence of contralateral upper tract recurrence. Thus, prophylactic contralateral resection was suggested for post-transplant upper tract urothelial carcinoma, especially for patients with aristolochic acid exposure.

Variation in Post-Transplant Cancer Incidence among Italian Kidney Transplant Recipients over a 25-Year Period

This cohort study examined 25-year variations in cancer incidence among 11,418 Italian recipients of kidney transplantation (KT) from 17 Italian centers. Cancer incidence was examined over three periods (1997-2004; 2005-2012; and 2013-2021) by internal (Incidence rate ratio-IRR) and external (standardized incidence ratios-SIR) comparisons. Poisson regression was used to assess trends. Overall, 1646 post-transplant cancers were diagnosed, with incidence rates/1000 person-years ranging from 15.5 in 1997-2004 to 21.0 in 2013-2021. Adjusted IRRs showed a significant reduction in incidence rates across periods for all cancers combined after exclusion of nonmelanoma skin cancers (IRR = 0.90, 95% confidence interval-CI: 0.76-1.07 in 2005-2012; IRR = 0.72, 95% CI: 0.60-0.87 in 2013-2021 vs. 1997-2004; P_trend < 0.01). In site-specific analyses, however, significant changes in incidence rates were observed only for Kaposi's sarcoma (KS; IRR = 0.37, 95% CI: 0.24-0.57 in 2005-2012; IRR = 0.09, 95% CI: 0.04-0.18 in 2013-2021; P_trend < 0.01). As compared to the general population, the overall post-transplant cancer risk in KT recipients was elevated, with a decreasing magnitude over time (SIR = 2.54, 95% CI: 2.26-2.85 in 1997-2004; SIR = 1.99, 95% CI: 1.83-2.16 in 2013-2021; P_trend < 0.01). A decline in SIRs was observed specifically for non-Hodgkin lymphoma and KS, though only the KS trend retained statistical significance after adjustment. In conclusion, apart from KS, no changes in the incidence of other cancers over time were observed among Italian KT recipients.

Diabetic Kidney Disease in Post-Transplant Diabetes Mellitus: Causes, Treatment and Outcomes

Kidney transplant recipients are a unique subgroup of chronic kidney disease patients due to their single functioning kidney, immunosuppressive agent usage, and long-term complications related to transplantation. Post-transplant diabetes mellitus (PTDM) has a significant adverse effect on renal outcomes in particular. As transplantations enable people to live longer, cardiovascular morbidity and mortality become more prevalent, and PTDM is a key risk factor for these complications. Although PTDM results from similar risk factors to those of type 2 diabetes, the conditions differ in their pathophysiology and clinical features. Transplantation itself is a risk factor for diabetes due to chronic exposure to immunosuppressive agents. Considering current evidence, this article describes the risk factors, pathogenesis, diagnostic criteria, prevention strategies, and management of PTDM. The therapeutic options are discussed regarding their safety and potential drug-drug interactions with immunosuppressive agents.

Changes over time in the causes of death with a functioning graft in kidney transplantation recipients

INTRODUCTION

Death with a functioning graft (DWFG) is the most frequent cause of loss of kidney transplantation (KT).

OBJECTIVE

To analyze the evolution of the causes of DWFG and the frequency of the types of cancer causing DWFG.

METHODS

Retrospective study of KT in Andalusia from 1984 to 2018. We analyzed the evolution according to eras (1984-1995; 1996-2007; 2008-2018) and according to post-transplant period (early death: first year post-KT; late death: after first year post-KT).

RESULTS

A total of 9905 KT were performed, registering 1861 DWFG. The most frequent causes were cardiovascular disease (25.1%), infections (21.5%) and cancer (19.9%). In early death we did not observe changes, and infections were always the main cause. In late death, cardiovascular death decreased (1984-1995: 35.2%, 1996-2007: 22.6%, 2008-2018: 23.9%), but infections (1984-1995: 12.5%, 1996-2007: 18.3%, 2008-2018: 19.9%) and, above all, cancer-related deaths increased (1984-1995: 21.8%, 1996-2007: 29%, 2008-2018: 26.8%) (P < .001). In the multivariable analysis for late death due to cardiovascular disease, recipient age, retransplantation, diabetes, and the first period were risk factors, while the risk of late death due to cancer and infections was associated with recent eras. In the first year after transplantation, the most frequent neoplasia causing DWFG was post-transplant lymphoproliferative disease, and after the first year, it was lung cancer, without differences when it was analyzed by eras.

CONCLUSIONS

Despite the greater comorbidity of the recipients, cardiovascular deaths have decreased. Cancer has been the main cause of late death in recent years. Lung cancer is the most frequent malignancy that causes DWFG in our transplant patients.

Immune-related mechanisms and immunotherapy in extragonadal germ cell tumors

Purpose of review

Extragonadal germ cell tumors (EGCTs) are relatively rare tumors, accounting for 1%-5% of all GCTs. In this review, we summarize the current research progress regarding the pathogenesis, diagnosis, and treatment of EGCTs from an immunology perspective.

Recent findings

The histological origin of EGCTs is related to a gonadal origin, but they are located outside the gonad. They show great variation in morphology and can occur in the cranium, mediastinum, sacrococcygeal bone, and other areas. The pathogenesis of EGCTs is poorly understood, and their differential diagnosis is extensive and challenging. EGCT behavior varies greatly according to patient age, histological subtype, and clinical stage.

Summary

This review provides ideas for the future application of immunology in the fight against such diseases, which is a hot topic currently.

Solid Organ Transplantation Is Associated with an Increased Rate of Mismatch Repair Deficiency and PIK3CA Mutations in Colorectal Cancer

Solid organ transplants are associated with a modestly increased risk of colorectal cancers (CRC). However, the molecular profile of these cancers has not been described. We hypothesized that transplant-related immunosuppression may promote development of more immunogenic tumors as suggested by a high tumor mutation burden or mismatch repair deficiency. We performed an electronic medical record search for patients seen in the Johns Hopkins University Health System (JHHS) between 2017 and 2022 who developed CRC following solid organ transplantation. A comparator cohort of patients treated for CRC at JHHS with molecular profiling data was also identified. In this case, 29 patients were identified that developed post-transplant CRC (renal transplant, n = 18; liver transplant, n = 8; kidney-liver transplantation, n = 3). Compared to the JHHS general population CRC cohort, patients who developed post-transplant CRC had a higher rate of mismatch repair deficiency (41% versus 12%, p-value = 0.0038), and elevated tumor mutation burden (median of 22 mut/Mb versus 3.5 mut/Mb, p-value = 0.033) (range 3.52-53.65). Post-transplant tumors were enriched for PIK3CA mutations (43% versus 24%, p-value = 0.042). Post-Transplant CRCs are associated with clinical and molecular features of immune sensitivity, supporting a potential role for impaired immune surveillance in shaping the landscape of CRCs. These results may help inform the management of patients with post-transplant CRC.

Skin cancer outcomes and risk factors in renal transplant recipients: Analysis of organ procurement and transplantation network data from 2000 to 2021

Purpose

Posttransplant skin cancer is the most common malignancy after patients have undergone renal transplantation. Through comprehensive observation with a large sample size nationwide, understanding the risk factors and outcome of posttransplant skin cancer will help to develop appropriate patient surveillance and disease prevention strategies.

Materials and methods

This retrospective population-based cohort study was based on Organ Procurement and Transplantation Network data released in March 2021. Characteristics and outcomes, including patient survival and graft survival of recipients, were compared. Risk factors for posttransplant skin cancer, cancer onset momentum, and mortality were determined.

Results

A total of 199,564 renal transplant recipients were included. After renal transplantation, 7,334 (3.68%), 6,093 (3.05%), and 936 (0.47%) were diagnosed with squamous cell carcinoma, basal cell carcinoma, and melanoma, respectively. Skin cancer was the major cause of death (squamous cell carcinoma: 23.8%, basal cell carcinoma: 18%, and melanoma: 41.6%). Five-year survival rates ranked from best to worst were as follows: basal cell carcinoma (96.7 [95% confidence interval: 96.3-97.2]%), squamous cell carcinoma (94.1 [93.5-94.6]%), melanoma (89.7 [87.7-91.6]%), and cancer-free (87.4 [87.2-87.5]%) (p < 0.001 for all except melanoma vs. cancer-free, p = 0.534). Regarding graft survival, death-censored graft survival, posttransplant skin cancer, and melanoma were significantly better than the cancer-free group (p < 0.001). Independent risk factors for developing posttransplant skin cancer included older age, male sex, Caucasian race, pretransplant malignancy, polycystic kidney disease-induced end-stage renal disease (ESRD), retransplantation, private health insurance, T-cell depletion induction, and tacrolimus/mycophenolic acid use. Caucasian race and pretransplant malignancy were independent risk factors for posttransplant skin cancer onset momentum. Male sex, Caucasian race, pretransplant malignancy, hypertension- or diabetes-induced ESRD, retransplantation, diabetes history, deceased donor, cyclosporin, and mTOR inhibitor use were independent risk factors for posttransplant skin cancer mortality.

Conclusion

Although posttransplant skin cancer is a major cause of recipient death, information regarding its impact on patient and graft survival is limited. Given the differences regarding risk factors for posttransplant skin cancer incidence, onset momentum, and mortality, personalized approaches to screening may be appropriate to address the complex issues encountered by kidney transplant recipients.

Comparison of artificial intelligence and human-based prediction and stratification of the risk of long-term kidney allograft failure

BACKGROUND

Clinical decisions are mainly driven by the ability of physicians to apply risk stratification to patients. However, this task is difficult as it requires complex integration of numerous parameters and is impacted by patient heterogeneity. We sought to evaluate the ability of transplant physicians to predict the risk of long-term allograft failure and compare them to a validated artificial intelligence (AI) prediction algorithm.

METHODS

We randomly selected 400 kidney transplant recipients from a qualified dataset of 4000 patients. For each patient, 44 features routinely collected during the first-year post-transplant were compiled in an electronic health record (EHR). We enrolled 9 transplant physicians at various career stages. At 1-year post-transplant, they blindly predicted the long-term graft survival with probabilities for each patient. Their predictions were compared with those of a validated prediction system (iBox). We assessed the determinants of each physician's prediction using a random forest survival model.

RESULTS

Among the 400 patients included, 84 graft failures occurred at 7 years post-evaluation. The iBox system demonstrates the best predictive performance with a discrimination of 0.79 and a median calibration error of 5.79%, while physicians tend to overestimate the risk of graft failure. Physicians' risk predictions show wide heterogeneity with a moderate intraclass correlation of 0.58. The determinants of physicians' prediction are disparate, with poor agreement regardless of their clinical experience.

CONCLUSIONS

This study shows the overall limited performance and consistency of physicians to predict the risk of long-term graft failure, demonstrated by the superior performances of the iBox. This study supports the use of a companion tool to help physicians in their prognostic judgement and decision-making in clinical care.

Scope and Consistency of Cancer Outcomes Reported in Randomized Trials in Kidney Transplant Recipients

Introduction

Cancer is an important outcome in kidney transplantation, but the scope and consistency of how cancer is defined and reported in trials involving kidney transplant recipients has not been evaluated. This study aimed to assess the range and variability of cancer outcomes in trials involving kidney transplant recipients.

Methods

The ClinicalTrials.gov database was searched from February 2000 to July 2021 to identify all randomized controlled trials (RCTs) in adult kidney transplant recipients, and which included cancer as a specified outcome. The definition of cancer, types of cancer (if any), timepoint(s) of measurement and method of aggregation were extracted for each cancer outcome.

Results

Of the 819 trials in kidney transplantation, only 84 (10%) included 1 or more cancer outcomes. Of these, 72 of 84 (86%) trials included cancer as a secondary outcome and 12 of 84 (14%) considered cancer as a primary outcome. The most frequent description of cancer was "malignancy" (n = 44, 43%), without reference to diagnostic criteria, histology, grade, or stage. The 2 most common cancer types were posttransplant lymphoproliferative disorder (PTLD) (n = 20, 20%) and nonmelanoma skin cancer (n = 10, 10%). Several methods of aggregation were identified, including incidence or rate (n = 47, 46%), frequency or proportion (n = 30, 29%), and time to event (n = 5, 5%). Approximately half the cancer outcomes were measured at a single time point (n = 44, 52%).

Conclusion

Cancer is an infrequently reported outcome and is inconsistently defined in trials of kidney transplant recipients. Consistent reporting of cancer outcomes using standardized definitions would provide important information on the impact of cancer in patients after kidney transplantation.

Post-transplant diabetes mellitus and renal cell cancer after renal transplantation

Background

Diabetes is a risk factor for cancer in the general population. However, few data are available on the association between post-transplant diabetes mellitus (PTDM) and cancer after transplantation.

Methods

We analyzed this issue in a Spanish cohort of patients without diabetes before transplantation. PTDM was diagnosed with consensus criteria at 12 months after transplantation and 12 months before the diagnosis of cancer. The association between PTDM and cancer (overall and specific types) was evaluated with regression analysis.

Results

During a follow-up of 12 years (interquartile range 8–14), 85 cases of 603 developed cancer (829/100 000/year) and 164 (27%) PTDM. The most frequent cancers were renal cell cancer (RCC) n = 15, 146/cases/100 000/year), lung (n = 12, 117/cases/100 000/year), colon (n = 9, 88/cases/100 000/year) and prostate (n = 9, 88/cases/100 000/year). In logistic regression, PTDM was not associated with cancer. Eight of the 164 patients with PTDM (4.9%) vs 7 of the 439 without PTDM developed RCC (1.6%) (P = .027). In multivariate analysis, PTDM was independently associated with RCC [odds ratio (OR) 2.92, confidence interval (CI) 1.03–8.27], adjusting for smoking (OR 4.020, 95% CI 1.34–12.02) and other covariates. PTDM was not associated with other types of cancer.

Conclusions

Patients with PTDM must be considered a population at risk for RCC and accordingly, the subject of active surveillance.

Transplant Onconephrology: An Update

Transplant onconephrology is a growing specialty focused on the health care of kidney transplant recipients with cancer. Given the complexities associated with the care of transplant patients, along with the advent of novel cancer therapies such as immune checkpoint inhibitors and chimeric antigen-receptor T cells, there is a dire need for the subspecialty of transplant onconephrology. The management of cancer in the setting of kidney transplantation is best accomplished by a multidisciplinary team, including transplant nephrologists, oncologists, and patients. This review addresses the current state and future opportunities for transplant onconephrology, including the roles of the multidisciplinary team, and related scientific and clinical knowledge.

Cemiplimab for advanced cutaneous squamous cell carcinoma in kidney transplant recipients

Background

Kidney transplant recipients (KTR) are at increased risk of cancer due to chronic immunosuppression. Non-melanoma skin cancer has an excess risk of approximately 250 times higher than the general population. Moreover, in solid organ transplant recipients (SOTR) these cancers have a more aggressive behavior, with an increased risk of metastasis and death. Cemiplimab, a human monoclonal IgG4 antibody against programmed cell death (PD-1) has shown considerable clinical activity in metastatic and locally advanced cutaneous squamous cell carcinoma (cSCC) in patients for whom no widely accepted standard of care exists. Cemiplimab has therefore been approved since 2018 for the treatment of advanced cSCC. However, data regarding the use of cemiplimab in SOTR and particularly in KTR are scarce and based on published case reports and small case series. In this study, we report on the real-life outcome of cemiplimab use in a Belgian cohort of seven KTR suffering from advanced cSCC.

Objective

To report on the overall response rate (ORR) and safety of cemiplimab in KTR in Belgium.

Results

Seven patients suffering from advanced cSCC, treated with cemiplimab, between 2018 and 2022, in Belgium were identified. Three patients were on corticosteroid monotherapy, one patient on tacrolimus monotherapy and three patients were on at least 2 immunosuppressants at start of cemiplimab. The ORR was 42.8%, stable disease was seen in 14.3% and progressive disease was found in 42.8% of the patients, respectively. The median administered number of cycles was 12, interquartile range (IQR) 25-75 [3.5 - 13.5]. All patients were treated with surgery before administration of cemiplimab, 71.4% received additional radiotherapy and only 1 patient was treated with chemotherapy prior to receiving cemiplimab. Biopsy-proven acute renal allograft rejection was observed in one patient, who eventually lost his graft function but showed a complete tumor response to treatment. Low grade skin toxicity was seen in one patient of the cohort.

Conclusion

The present case series shows that the use of cemiplimab in KTR with advanced cSCC who failed to respond to previous surgery, chemo - and/or radiotherapy treatment is associated with an ORR of 42.8% with minimal risk of graft rejection (14.3%) and good tolerance.

Causal effect of autoimmune liver diseases on cancer: Meta-analyses of cohort studies and Mendelian randomization study

BACKGROUND AND AIMS

Prior studies suggested that patients with autoimmune liver diseases (AiLDs) had an increased risk of cancer, whereas the causal effect remained unclear.

METHODS

Meta-analyses concerning the relationship between AiLD and cancer risk were performed to calculate the pooled relative risk (RR) and corresponding 95% confidence intervals (CIs). Then, the associations with a p value of <.05 were further validated by two-sample Mendelian randomization studies.

RESULTS

A total of 37 cohort studies covering more than 34 558 patients were included, and we observed an increased risk of overall cancers (pooled RR = 3.64, 95% CI: 2.64-5.03, p < .001) and cancer-related death (pooled RR = 2.48, 95% CI: 1.73-3.53, p < .001) for patients with AiLD. Besides, overall and several site-specific cancers risk were found in patients with primary biliary cholangitis (PBC), autoimmune hepatitis (AIH), and primary sclerosing cholangitis (PSC) (p < .05). However, associations between genetically predisposed AIH, PBC, and PSC and the risk of specific cancers did not reach a significant level, except for PBC and gastric cancer (OR = 0.96, 95% CI: 0.93-0.99; p = .02).

CONCLUSIONS

In addition to hepatobiliary cancer, results from the meta-analyses suggest that patients with AiLD might have an increased risk of several extrahepatobiliary cancers. However, the causal role of AiLD in cancer development needs to be further investigated.

Alteraciones neoplásicas en el paciente trasplantado renal. Una revisión sistemática

Introducción: El trasplante renal se ha destacado como la mejor terapia renal sustitutiva para la enfermedad renal crónica terminal, aunque conlleva una serie de riesgos entre los que el cáncer se destaca cada vez más, por lo que parece importante determinar el impacto que tiene en esta población.Objetivo: Conocer y sintetizar la evidencia científica acerca de la incidencia de neoplasias en pacientes trasplantados renales, así como las variables relacionadas con las mismas.Metodología: Se realizó una revisión sistemática en la que se incluyeron 14 artículos procedentes de las bases de Pubmed, Scopus, Scielo, WOS y Google Académico. Como términos MeSH se utilizaron: neoplasias (neoplasms), trasplante de riñón (kidney transplantation), incidencia (incidence), riesgo (risk), factores de riesgo (risk factors). Se incluyeron artículos originales en inglés y español, en población trasplantada adulta.Resultados: Se incluyeron 14 artículos de diseño observacional. De la revisión emergieron como principales variables: incidencia general, datos demográficos y tratamientos previos, otras características asociadas, tumores más frecuentes y medidas preventivas.Conclusiones: La incidencia de neoplasias en el paciente trasplantado es alta, sobre todo en la edad avanzada y pacientes con tratamiento inmunosupresor con ciclosporina y azatioprina siendo este último, junto al trasplante procedente de cadáver, los principales factores de riesgo encontrados. Los cánceres de piel no melanoma son los más prevalentes y como medidas de prevención se destaca llevar a cabo un cribado rutinario, fomento de una vida saludable, y promoción y potenciación de la vacunación de la hepatitis B.

Immune checkpoint inhibitors and kidney disease

PURPOSE OF REVIEW

Immune checkpoint inhibitors (ICIs) have changed the landscape of cancer treatment. However, use of ICIs can be limited by inflammatory toxicities referred to as immune-related adverse events (irAEs). ICI-associated acute kidney injury (ICI-associated AKI) affects 3-5% of ICI users.

RECENT FINDINGS

With the rapidly growing indication of ICI, knowledge of ICI-associated kidney toxicity has also expanded from case series to large multicentre cohort studies. In this review, we discuss the clinical features, risk factors, clinicopathological correlations and prognosis of ICI-associated AKI from the most recent rigorously conducted retrospective cohort studies. We also discuss recent advances in diagnostic biomarker investigation, treatment and the unique challenge faced in the kidney transplant population.

SUMMARY

With more comprehensive understanding of the clinical features and risk factors, ICI-associated AKI is commonly diagnosed clinically, especially given the inherent challenges performing a kidney biopsy in the cancer population; however, this highlights the urgent need for improved noninvasive diagnostic biomarkers to aid diagnosis and prognosis. Prospective studies are needed to better define the optimal treatment of ICI-associated AKI and to minimize the risk of graft loss in patients with kidney transplant who require ICIs.

Malignancies in adult kidney transplant candidates and recipients: current status

Posttransplant malignancies, particularly recurrent and de novo, in solid organs including kidney transplant recipients (KTRs) are a significant complication associated with substantial mortality, largely attributed to long-term immunosuppression necessary to maintain allograft tolerance. Older age at transplantation and oncogenic virus infection along with pretransplant malignancies are among the main factors contributing to the risk of cancer in this population. As the mean age of transplant candidates rises, the rate of transplant recipients with pretransplant malignancies also increases. The eligibility criteria for transplantation in patients with prior cancer have recently changed. The overall risk of posttransplant malignancies is at least double after transplantation including KTRs relative to the general population, most pronounced for skin cancers associated with UV radiation and virally-mediated tumors. The risk of renal cell carcinoma is specifically increased in the kidney transplant population. The therapy of cancer in transplant patients is associated with risk of higher toxicity, and graft rejection and/or impairment, which poses a unique challenge in the management. Reduction of immunosuppression and the use of mTOR inhibitors are common after cancer diagnosis, although optimal immunosuppression for transplant recipients with cancer remains undefined. Suboptimal cancer treatment contributing to a worse prognosis has been reported for malignancies in this population. In this article, we focus on the prevalence and outcomes of posttransplant malignancies, cancer therapy including a short overview of immunotherapy, cancer screening and prevention strategies, and immunosuppression as a cancer risk factor. The 2020/2021 recommendations of the Kidney Diseases Improving Global Outcome (KDIGO) and American Society of Transplantation (AST) for transplant candidates with a history of cancer are presented.

Whole-exome sequencing identified mutational profiles of urothelial carcinoma post kidney transplantation

Kidney transplantation is a lifesaving option for patients with end-stage kidney disease. In Taiwan, urothelial carcinoma (UC) is the most common de novo cancer after kidney transplantation (KT). UC has a greater degree of molecular heterogeneity than do other solid tumors. Few studies have explored genomic alterations in UC after KT. We performed whole-exome sequencing to compare the genetic alterations in UC developed after kidney transplantation (UCKT) and in UC in patients on hemodialysis (UCHD). After mapping and variant calling, 18,733 and 11,093 variants were identified in patients with UCKT and UCHD, respectively. We excluded known single-nucleotide polymorphisms (SNPs) and retained genes that were annotated in the Catalogue of Somatic Mutations in Cancer (COSMIC), in the Integrative Onco Genomic cancer mutations browser (IntOGen), and in the Cancer Genome Atlas (TCGA) database of genes associated with bladder cancer. A total of 14 UCKT-specific genes with SNPs identified in more than two patients were included in further analyses. The single-base substitution (SBS) profile and signatures showed a relative high T > A pattern compared to COMSIC UC mutations. Ingenuity pathway analysis was used to explore the connections among these genes. GNAQ, IKZF1, and NTRK3 were identified as potentially involved in the signaling network of UCKT. The genetic analysis of posttransplant malignancies may elucidate a fundamental aspect of the molecular pathogenesis of UCKT.