Renal effects of targeted anticancer therapies

Hypertension in Childhood Cancer Survivors: Causes, Screening, and Management

PURPOSE OF REVIEW

Survivors of childhood cancer and hematopoietic cell transplant are at risk for developing chronic health conditions, including hypertension. Studies have identified hypertension as an influential risk factor for late kidney dysfunction and cardiovascular disease in childhood cancer survivors. The overall risk of hypertension depends on the specific cancer treatment, from chemotherapy to surgery to radiation. In this report, we aim to review the main causes of hypertension in childhood cancer survivors, with a focus on newer therapies, as well as the current recommendations for screening and management of hypertension in this patient population.

RECENT FINDINGS

Novel targeted therapies and immunotherapies are being increasingly used in pediatric cancer treatment, with unclear impact on long-term health. Screening guidelines for hypertension in the survivor population have been issued by various childhood cancer cooperative groups based on best available evidence and expert opinion. Newer studies have focused on individual risk prediction, which may help improve the diagnosis and management of hypertension, particularly in higher-risk individuals. Despite the importance of hypertension as one of the few modifiable risk factors for cardiovascular and renal health, studies have yet to define optimal blood pressure targets, screening parameters, or management strategies in childhood cancer survivors. Additionally, further studies are needed to demonstrate improvement in outcomes following interventions for hypertension specifically in this patient population.

Cancer therapy in patients with reduced kidney function

Chronic kidney disease (CKD) and cancer constitute two major public health burdens, and both are on the rise. Moreover, the number of patients affected simultaneously by both conditions is growing. The potential nephrotoxic effect of cancer therapies is particularly important for patients with CKD, as they are also affected by several comorbidities. Therefore, administering the right therapy at the right dose for patients with decreased kidney function can represent a daunting challenge. We review in detail the renal toxicities of anticancer therapies, i.e. conventional chemotherapy, targeted therapy, immune checkpoint inhibitors and radioligand therapies, issue recommendations for patient monitoring along with guidance on when to withdraw treatment and suggest dosage guidelines for select agents in advanced stage CKD. Various electrolytes disturbances can occur as the result of the administration of anticancer agents in the patient with decreased kidney function. These patients are prone to developing hyponatremia, hyperkalemia and other metabolic abnormalities because of a decreased glomerular filtration rate. Therefore, all electrolytes, minerals and acid base status should be checked at baseline and before each administration of chemotherapeutic agents. Moreover, studies on patients on kidney replacement therapy are very limited and only single cases or small case series have been published. Therefore, clinical therapeutical decisions in cancer patients with decreased function should be made by multidisciplinary teams constituted of medical oncologists, nephrologists and other specialists. Onconephrology is an evolving and expanding subspecialty. It is crucial to consider anticancer drug treatment in these patients and offer them a chance to be treated effectively.

Artificial Intelligence and Machine Learning Models for Predicting Drug-Induced Kidney Injury in Small Molecules

BACKGROUND/OBJECTIVES

Drug-Induced Kidney Injury (DIKI) presents a significant challenge in drug development, often leading to clinical-stage failures. The early prediction of DIKI risk can improve drug safety and development efficiency. Existing models tend to focus on physicochemical properties alone, often overlooking drug-target interactions crucial for DIKI. This study introduces an AI/ML (artificial intelligence/machine learning) model that integrates both physicochemical properties and off-target interactions to enhance DIKI prediction.

METHODS

We compiled a dataset of 360 FDA-classified compounds (231 non-nephrotoxic and 129 nephrotoxic) and predicted 6064 off-target interactions, 59% of which were validated in vitro. We also calculated 55 physicochemical properties for these compounds. Machine learning (ML) models were developed using four algorithms: Ridge Logistic Regression (RLR), Support Vector Machine (SVM), Random Forest (RF), and Neural Network (NN). These models were then combined into an ensemble model for enhanced performance.

RESULTS

The ensemble model achieved an ROC-AUC of 0.86, with a sensitivity and specificity of 0.79 and 0.78, respectively. The key predictive features included 38 off-target interactions and physicochemical properties such as the number of metabolites, polar surface area (PSA), pKa, and fraction of Sp3-hybridized carbons (fsp3). These features effectively distinguished DIKI from non-DIKI compounds.

CONCLUSIONS

The integrated model, which combines both physicochemical properties and off-target interaction data, significantly improved DIKI prediction accuracy compared to models that rely on either data type alone. This AI/ML model provides a promising early screening tool for identifying compounds with lower DIKI risk, facilitating safer drug development.

Acute Kidney Injury Associated with Anticancer Therapies: Small Molecules and Targeted Therapies

Molecular targeted therapy has revolutionized cancer treatment by significantly improving patient survival compared with standard conventional chemotherapies. The use of these drugs targets specific molecules or targets, which block growth and spread of cancer cells. Many of these therapies have been approved for use with remarkable success in breast, blood, colorectal, lung, and ovarian cancers. The advantage over conventional chemotherapy is its ability to deliver drugs effectively with high specificity while being less toxic. Although known as "targeted," many of these agents lack specificity and selectivity, and they tend to inhibit multiple targets, including those in the kidneys. The side effects usually arise because of dysregulation of targets of the inhibited molecule in normal tissue. The off-target effects are caused by drug binding to unintended targets. The on-target effects are associated with inhibition toward the pathway reflecting inappropriate inhibition or activation of the intended drug target. Early detection and correct management of kidney toxicities is crucial to preserve kidney functions. The knowledge of these toxicities helps guide optimal and continued utilization of these potent therapies. This review summarizes the different types of molecular targeted therapies used in the treatment of cancer and the incidence, severity, and pattern of nephrotoxicity caused by them, with their plausible mechanism and proposed treatment recommendations.

Global epidemiology of kidney cancer

Kidney cancer (KC) is a disease with a rising worldwide incidence estimated at 400 000 new cases annually, and a worldwide mortality rate approaching 175 000 deaths per year. Current projections suggest incidence continuing to increase over the next decade, emphasizing the urgency of addressing this significant global health trend. Despite the overall increases in incidence and mortality, striking social disparities are evident. Low- and middle-income countries bear a disproportionate burden of the disease, with higher mortality rates and later-stage diagnoses, underscoring the critical role of socioeconomic factors in disease prevalence and outcomes. The major risk factors for KC, including smoking, obesity, hypertension and occupational exposure to harmful substances, must be taken into account. Importantly, these risk factors also often contribute to kidney injury, a condition that the review identifies as a significant, yet under-recognized, precursor to KC. Finally, the indispensable role of nephrologists is underscored in managing this complex disease landscape. Nephrologists are at the forefront of detecting and managing kidney injuries, and their role in mitigating the risk of KC is becoming increasingly apparent. Through this comprehensive analysis, we aim to facilitate a more nuanced understanding of KC's epidemiology and determinants providing valuable insights for researchers, clinicians and policymakers alike.

How to deal with renal toxicities from immune-based combination treatments in metastatic renal cell carcinoma. A nephrological consultation for Oncologists

We are witnessing a revolution in the treatment of metastatic renal cell carcinoma (mRCC). Indeed, several immune-based combinations (ICI [immune checkpoint inhibitor] + ICI, or ICI + antiangiogenic agents) have been approved as first-line therapy for mRCC after demonstrating superior efficacy over the previous standard. Despite all the improvements made, safety remains a critical issue, adverse events (AEs) being the main reason for drug discontinuations or dose reductions, ultimately resulting in an increased risk of losing efficacy. Thus, a good understanding of the AEs associated with the use of immune-based combinations, their prevention, and management, are key in order to maximize therapeutic effectiveness. Among these AEs, renal ones are relatively frequent, but always difficult to be diagnosed, not to take into account that it is often difficult to determine which drug is to blame for such toxicities. Chronic kidney disease (CKD) is a common finding in patients with RCC, either as a pre-existing condition and/or as a consequence of cancer and its treatment; furthermore, CKD, especially in advanced stages and in patients undergoing dialysis, may influence the pharmacokinetics and pharmacodynamics properties of anticancer agents. Finally, managing cancer therapy in kidney transplanted patients is another challenge. In this review, we discuss the therapy management of immune-based combinations in patients with CKD, on dialysis, or transplanted, as well as their renal toxicities, with a focus on their prevention, detection and practical management, taking into account the crucial role of the consulting nephrologist within the multidisciplinary care of these patients.

Pharmacotherapy considerations in patients who develop acute kidney injury during anti-cancer therapy

INTRODUCTION

Acute kidney injury (AKI) frequently develops in patients receiving cancer therapy and requires a wide differential diagnosis due to possible role of unique cancer and drug-related factors, in addition to common pre- and post-renal causes. Rapid development of new molecular targeted anti-cancer drugs and immunotherapies has opened unprecedented possibilities of treatment at the price of an increased spectrum of renal side effects.

AREAS COVERED

The present review aims at providing a state-of-the-art picture of AKI in cancer patient (PubMed and Embase libraries were searched from inception to January 2024), with a focus on differential diagnosis and management of diverse clinical settings. Reports of parenchymal AKI due to glomerular, microvascular, tubular and interstitial damage have been constantly increasing. Complex electrolyte and acid-base disorders can coexist. The role of renal biopsy and possible therapeutic approaches are also discussed.

EXPERT OPINION

Onconephrology has become an important subspecialty of clinical nephrology, requiring constantly updated skills and a high degree of interdisciplinary integration to tackle diagnostic challenges and even therapeutic and ethical dilemmas. Integrated onconephrological guidelines and availability of biomarkers may provide new tools for management of this unique type of patients in the near future.

Case report: Successful treatment of a patient undergoing haemodialysis with multifocal hepatocellular carcinoma using atezolizumab and bevacizumab

In the last five years, the advent of combination immune checkpoint inhibitor atezolizumab and anti-angiogenic agent bevacizumab has transformed treatment of unresectable hepatocellular carcinoma. As patient outcomes improve, healthcare professionals will more frequently encounter patients with concomitant hepatocellular cancer and end stage kidney disease on haemodialysis. We present the first case in the literature of a 58-year-old male with multifocal hepatocellular carcinoma undertaking regular haemodialysis who was successfully treated with atezolizumab and bevacizumab with a partial response and stable disease for two years, who suffered grade 1 fatigue, grade 2 hypertension and eventually grade 3 wound infection leading to cessation of bevacizumab. After disease progression on atezolizumab monotherapy, all chemotherapy was stopped. We embed this case in a review of the current literature of atezolizumab and bevacizumab use in patients undertaking haemodialysis and conclude that both targeted therapies may be safely used in these patients. We recommend joint close management of these patients between oncology and nephrology teams, with initial cardiovascular risk stratification before commencing atezolizumab and bevacizumab therapy. During therapy, there should be regular monitoring of blood pressure, or proteinuria if the patient is oliguric under guidance of the dialysis team if preservation of residual renal function is required.

The Influence of Betulin Derivatives EB5 and ECH147 on the Expression of Selected TGFβ Superfamily Genes, TGFβ1, GDF15 and BMP2, in Renal Proximal Tubule Epithelial Cells

Betulin derivatives are proposed to serve as an alternative to the drugs already established in oncologic treatment. Drug-induced nephrotoxicity leading to acute kidney injury frequently accompanies cancer treatment, and thus there is a need to research the effects of betulin derivatives on renal cells. The objective of our study was to assess the influence of the betulin derivatives 28-propynylobetulin (EB5) and 29-diethoxyphosphoryl-28-propynylobetulin (ECH147) on the expression of TGFβ1, BMP2 and GDF15 in renal proximal tubule epithelial cells (RPTECs) cultured in vitro. The changes in mRNA expression and copy numbers were assessed using real-time reverse transcription quantitative polymerase chain reaction (RT-qPCR) and the standard curve method, respectively. An enzyme-linked immunosorbent assay (ELISA) was used to evaluate the effect of the betulin derivatives on the protein concentration in the culture media's supernatant. The assessment of the betulin derivatives' influence on gene expression demonstrated that the mRNA level and protein concentration did not always correlate with each other. Each of the tested compounds affected the mRNA expression. The RT-qPCR analyses showed that EB5 and ECH147 induced effects similar to those of betulin or cisplatin and resulted in a decrease in the mRNA copy number of all the analyzed genes. The ELISA demonstrated that EB5 and ECH147 elevated the protein concentration of TGFβ1 and GDF15, while the level of BMP2 decreased. The concentration of the derivatives used in the treatment was crucial, but the effects did not always exhibit a simple linear dose-dependent relationship. Betulin and its derivatives, EB5 and ECH147, influenced the gene expression of TGFβ1, BMP2 and GDF15 in the renal proximal tubule epithelial cells. The observed effects raise the question of whether treatment with these compounds could promote the development of renal fibrosis.

Development and Validation of a Prediction Model for Kidney Failure in Long-Term Survivors of Childhood Cancer

PURPOSE

Kidney failure is a rare but serious late effect following treatment for childhood cancer. We developed a model using demographic and treatment characteristics to predict individual risk of kidney failure among 5-year survivors of childhood cancer.

METHODS

Five-year survivors from the Childhood Cancer Survivor Study (CCSS) without history of kidney failure (n = 25,483) were assessed for subsequent kidney failure (ie, dialysis, kidney transplantation, or kidney-related death) by age 40 years. Outcomes were identified by self-report and linkage with the Organ Procurement and Transplantation Network and the National Death Index. A sibling cohort (n = 5,045) served as a comparator. Piecewise exponential models accounting for race/ethnicity, age at diagnosis, nephrectomy, chemotherapy, radiotherapy, congenital genitourinary anomalies, and early-onset hypertension estimated the relationships between potential predictors and kidney failure, using area under the curve (AUC) and concordance (C) statistic to evaluate predictive power. Regression coefficient estimates were converted to integer risk scores. The St Jude Lifetime Cohort Study and the National Wilms Tumor Study served as validation cohorts.

RESULTS

Among CCSS survivors, 204 developed late kidney failure. Prediction models achieved an AUC of 0.65-0.67 and a C-statistic of 0.68-0.69 for kidney failure by age 40 years. Validation cohort AUC and C-statistics were 0.88/0.88 for the St Jude Lifetime Cohort Study (n = 8) and 0.67/0.64 for the National Wilms Tumor Study (n = 91). Risk scores were collapsed to form statistically distinct low- (n = 17,762), moderate- (n = 3,784), and high-risk (n = 716) groups, corresponding to cumulative incidences in CCSS of kidney failure by age 40 years of 0.6% (95% CI, 0.4 to 0.7), 2.1% (95% CI, 1.5 to 2.9), and 7.5% (95% CI, 4.3 to 11.6), respectively, compared with 0.2% (95% CI, 0.1 to 0.5) among siblings.

CONCLUSION

Prediction models accurately identify childhood cancer survivors at low, moderate, and high risk for late kidney failure and may inform screening and interventional strategies.

Malignancy diseases and kidneys: A nephrologist prospect and updated review

Acute kidney injury (AKI), chronic renal failure, and tubular abnormalities represent the kidney disease spectrum of malignancy. Prompt diagnosis and treatment may prevent or reverse these complications. The pathogenesis of AKI in cancer is multifactorial. AKI affects outcomes in cancer, oncological therapy withdrawal, increased hospitalization rate, and hospital stay. Renal function derangement can be recovered with early detection and targeted therapy of cancers. Identifying patients at higher risk of renal damage and implementing preventive measures without sacrificing the benefits of oncological therapy improve survival. Multidisciplinary approaches, such as relieving obstruction, hydration, etc., are required to minimize the kidney injury rate. Different keywords, texts, and phrases were used to search Google, EMBASE, PubMed, Scopus, and Google Scholar for related original and review articles that serve the article's aim well. In this nonsystematic article, we aimed to review the published data on cancer-associated kidney complications, their pathogenesis, management, prevention, and the latest updates. Kidney involvement in cancer occurs due to tumor therapy, direct kidney invasion by tumor, or tumor complications. Early diagnosis and therapy improve the survival rate. Pathogenesis of cancer-related kidney involvement is different and complicated. Clinicians' awareness of all the potential causes of cancer-related complications is essential, and a kidney biopsy should be conducted to confirm the kidney pathologies. Chronic kidney disease is a known complication in malignancy and therapies. Hence, avoiding nephrotoxic drugs, dose standardization, and early cancer detection are mandatory measures to prevent renal involvement.

The Onco-Nephrology Field: The Role of Personalized Chemotherapy to Prevent Kidney Damage

In recent years, the onco-nephrology field has acquired a relevant role in internal medicine due to the growing number of cases of renal dysfunction that have been observed in cancer patients. This clinical complication can be induced by the tumor itself (for example, due to obstructive phenomena affecting the excretory tract or by neoplastic dissemination) or by chemotherapy, as it is potentially nephrotoxic. Kidney damage can manifest as acute kidney injury or represent a worsening of pre-existing chronic kidney disease. In cancer patients, physicians should try to set preventive strategies to safeguard the renal function, avoiding the concomitant use of nephrotoxic drugs, personalizing the dose of chemotherapy according to the glomerular filtration rate (GFR) and using an appropriate hydration therapy in combination with nephroprotective compounds. To prevent renal dysfunction, a new possible tool useful in the field of onco-nephrology would be the development of a personalized algorithm for the patient based on body composition parameters, gender, nutritional status, GFR and genetic polymorphisms.

Onconephrology 2022: An Update

Onconephrology is an upcoming and expanding subspecialty that deals with the intersections between hematology/oncology and nephrology. With the paradigm shift in the understanding of cancer immunobiology and mechanisms of oncotherapeutic drug toxicities, it is important for a nephrologist to have a sound understanding of this field. Over the last 5 years, there have been immense developments in our understanding of kidney-related adverse events from various targeted, immuno- and cellular-based therapies. Pathogenic mechanisms of electrolyte imbalance, hypertension (oncohypertension), and AKI from multiple forms of cancer therapies have been explored. Significant research has also been conducted in the field of transplant onconephrology. In this review, we have tried to assimilate the most recent updates in the last 2 years in this ever-growing and fascinating field.

Onconephrology: Update in Anticancer Drug-Related Nephrotoxicity

The relation that connects cancer and renal damage is bidirectional and this renal damage worsens quality of life and increases morbidity in high-complexity patients such as patients with cancer and kidney injury. Strikingly, in the last decade, the treatment of advanced cancer has clearly advanced in terms of new therapeutic strategies with the ability to transform the advanced metastatic cancer in a chronic condition. In this new era of cancer therapies, cancer treatment including conventional chemotherapy, targeted cancer agents and immunotherapies among others are significantly associated with kidney injury. Renal toxicity that is currently seen in onconephrology departments is in part related to the new therapies such as immunotherapy, and to the prolonged survival achieved at the expense of increasing therapy lines, and a combination of different drugs. In this review, we will discuss in a practical way, nephrotoxicity caused by the main oncospecific treatments such as classical chemotherapy agents, targeted therapies, and immunotherapy. In addition, strategies for prevention and management recommendations in patients with malignancies and kidney disease will also be addressed.

Chronic kidney disease in cancer patients, the analysis of a large oncology database from Eastern Europe

Introduction

Kidney dysfunction is prevalent in oncology patients and has an impact on their treatment and quality of life. The aim of our study was to analyze the prevalence of CKD in a large cohort of several types of cancer patients in an East European Region.

Material and methods

We conducted an observational retrospective cohort study on 5831 consecutive, biopsy-diagnosed cancer patients between January 2019 –December 2020 in the largest oncology hospital and outpatient clinic in Western Romania. 4342 subjects were included in the statistical analysis.

Results and discussion

From the 24 cancer types, the most prevalent cancers were represented by: breast (22.02%), lung (10.18%) and colonic cancer (9.51%). The prevalence of CKD (G3 –G5) was 12.27% after the first year of follow-up and 13.42 after the second year. The prevalence of CKD was higher in patients with renal (50%), urinary tract (33.6%) and pancreatic cancers (19.6%) and lower in patients with colonic cancers (5.3%) and brain tumors (2.5%). At the end of our 2-year survey period, 0,7% of the CKD cases had an eGFR around 6 ml/min/1.73m2 –an indication for renal replacement therapy.

Conclusion

Oncology patients have a significantly higher prevalence of CKD compared to the general population, dependent of the age of the patients and the type of cancer. The prevalence of advanced CKD was surprisingly high (stages G4-G5 Pre-Dialysis 22.15%) one third of the CKD- G5 patients having indication for initiation of renal replacement therapy. An onco- nephrology team should be needed for the best medical care of these patients.

Pegylated Liposomal Doxorubicin and Kidney-Limited Thrombotic Microangiopathy in a Kidney Transplant Recipient: A Case Report

A 64-year-old man with Kaposi sarcoma in clinical remission after treatment with pegylated liposomal doxorubicin and a history of deceased-donor kidney transplantation 4 years prior presented with a slowly progressive increase in his serum creatinine level, well-controlled hypertension, stable subnephrotic-range proteinuria, and bland urinary sediment. An allograft kidney biopsy demonstrated thrombotic microangiopathy, without clinical or laboratory features of systemic involvement. Based on the timing of drug initiation preceding thrombotic microangiopathy, complete recovery after drug withdrawal, and the absence of other etiologies, it was concluded that pegylated liposomal doxorubicin was the likely cause of kidney-limited thrombotic microangiopathy. When pegylated liposomal doxorubicin was resumed, the patient developed hypertension and kidney allograft dysfunction. A new kidney biopsy was not performed because of the overall risk benefit. The case highlights the importance of recognizing novel etiologies of thrombotic microangiopathy in kidney transplant patients with malignancy. Although Kaposi sarcoma has not been linked to thrombotic microangiopathy, pegylated liposomal doxorubicin has been increasingly associated with drug-induced thrombotic microangiopathy. To our knowledge, this is the first case report that etiologically links pegylated liposomal doxorubicin to kidney-limited thrombotic microangiopathy in a kidney transplant patient.

Stage at Diagnosis and Prognosis of Colorectal, Stomach, Lung, Liver, Kidney, and Bladder Cancers in Dialysis Patients: A Multicenter Retrospective Study Using Cancer Registry Data and Administrative Data

<b><i>Background:</i></b> Cancer is an important comorbidity that can affect survival in dialysis patients. However, it is unclear if dialysis patients who develop cancer are disadvantaged by later detection and poorer prognosis. This study comparatively examined the stage at diagnosis and prognosis of several common cancer types in dialysis and nondialysis patients. <b><i>Methods:</i></b> In this retrospective cohort study, cancer registry data were linked with administrative data to identify dialysis and nondialysis patients with any new diagnosis of cancer between 2010 and 2015 at 36 hospitals in Osaka Prefecture, Japan. In these patients, we identified the cancer stage at diagnosis for patients with colorectal, stomach, lung, liver, kidney, and bladder cancers. The association between dialysis and survival time (up to 3 years of follow-up) was examined for each cancer type using Cox proportional hazards models that adjusted for age, sex, and cancer stage. <b><i>Results:</i></b> We analyzed 2,161 dialysis patients and 158,964 nondialysis patients with cancer. Dialysis patients had a higher prevalence of colorectal, liver, and kidney cancers than nondialysis patients. Colorectal, stomach, lung, liver, and kidney cancers were diagnosed earlier in dialysis patients, whereas bladder cancer was diagnosed at an advanced stage. The Cox proportional hazards models revealed that mortality was significantly higher in dialysis patients with colorectal, stomach, lung, and bladder cancers than in nondialysis patients (all <i>p</i> &#x3c; 0.05). <b><i>Conclusions:</i></b> Dialysis patients had higher mortality for several common cancers despite their earlier detection. This poorer prognosis may be influenced by the unavailability and complications of cancer treatment for these patients.

Prediction and Clinically Important Factors of Acute Kidney Injury Non-recovery

OBJECTIVE

This study aimed to identify phenotypic clinical features associated with acute kidney injury (AKI) to predict non-recovery from AKI at hospital discharge using electronic health record data.

METHODS

Data for hospitalized patients in the AKI Recovery Evaluation Study were derived from a large healthcare delivery system in Taiwan between January 2011 and December 2017. Living patients with AKI non-recovery were used to derive and validate multiple predictive models. In total, 64 candidates variables, such as demographic characteristics, comorbidities, healthcare services utilization, laboratory values, and nephrotoxic medication use, were measured within 1 year before the index admission and during hospitalization for AKI.

RESULTS

Among the top 20 important features in the predictive model, 8 features had a positive effect on AKI non-recovery prediction: AKI during hospitalization, serum creatinine (SCr) level at admission, receipt of dialysis during hospitalization, baseline comorbidity of cancer, AKI at admission, baseline lymphocyte count, baseline potassium, and low-density lipoprotein cholesterol levels. The predicted AKI non-recovery risk model using the eXtreme Gradient Boosting (XGBoost) algorithm achieved an area under the receiver operating characteristic (AUROC) curve statistic of 0.807, discrimination with a sensitivity of 0.724, and a specificity of 0.738 in the temporal validation cohort.

CONCLUSION

The machine learning model approach can accurately predict AKI non-recovery using routinely collected health data in clinical practice. These results suggest that multifactorial risk factors are involved in AKI non-recovery, requiring patient-centered risk assessments and promotion of post-discharge AKI care to prevent AKI complications.

Renal Cell Carcinoma and Kidney Transplantation: A Narrative Review

Kidney transplant recipients (KTRs) are at increased risk of developing renal cell carcinoma (RCC). The cancer can be encountered at different steps in the transplant process. RCC found during work-up of a transplant candidate needs treatment and to limit the risk of recurrence usually a mandatory observation period before transplantation is recommended. An observation period may be omitted for candidates with incidentally discovered and excised small RCCs (<3 cm). Likewise, RCC in the donor organ may not always preclude usage if tumor is small (<2 to 4 cm) and removed with clear margins before transplantation. After transplantation, 90% of RCCs are detected in the native kidneys, particularly if acquired cystic kidney disease has developed during prolonged dialysis. Screening for RCC after transplantation has not been found cost-effective. Treatment of RCC in KTRs poses challenges with adjustments of immunosuppression and oncologic treatments. For localized RCC, excision or nephrectomy is often curative. For metastatic RCC, recent landmark trials in the nontransplanted population demonstrate that immunotherapy combinations improve survival. Dedicated trials in KTRs are lacking. Case series on immune checkpoint inhibitors in solid organ recipients with a range of cancer types indicate partial or complete tumor response in approximately one-third of the patients at the cost of rejection developing in ~40%.

The Role of Circulating Biomarkers in the Oncological Management of Metastatic Renal Cell Carcinoma: Where Do We Stand Now?

Renal cell carcinoma (RCC) is an increasingly common malignancy that can progress to metastatic renal cell carcinoma (mRCC) in approximately one-third of RCC patients. The 5-year survival rate for mRCC is abysmally low, and, at the present time, there are sparingly few if any effective treatments. Current surgical and pharmacological treatments can have a long-lasting impact on renal function, as well. Thus, there is a compelling unmet need to discover novel biomarkers and surveillance methods to improve patient outcomes with more targeted therapies earlier in the course of the disease. Circulating biomarkers, such as circulating tumor DNA, noncoding RNA, proteins, extracellular vesicles, or cancer cells themselves potentially represent a minimally invasive tool to fill this gap and accelerate both diagnosis and treatment. Here, we discuss the clinical relevance of different circulating biomarkers in metastatic renal cell carcinoma by clarifying their potential role as novel biomarkers of response or resistance to treatments but also by guiding clinicians in novel therapeutic approaches.

Treatment of Acute Kidney Injury in Cancer Patients

Acute kidney injury (AKI), either of pre-renal, renal or post-renal origin, is an important complication in cancer patients, resulting in worse prognosis, withdrawal from effective oncological treatments, longer hospitalizations and increased costs. The aim of this article is to provide a literature review of general and cause-specific treatment strategies for AKI, providing a helpful guide for clinical practice. We propose to classify AKI as patient-related, cancer-related and treatment-related in order to optimize therapeutic interventions. In the setting of patient-related causes, proper assessment of hydration status and avoidance of concomitant nephrotoxic medications is key. Cancer-related causes mainly encompass urinary compression/obstruction, direct tumoural kidney involvement and cancer-induced hypercalcaemia. Rapid recognition and specific treatment can potentially restore renal function. Finally, a pre-treatment comprehensive evaluation of risks and benefits of each treatment should always be performed to identify patients at high risk of treatment-related renal damage and allow the implementation of preventive measures without losing the potentialities of the oncological treatment. Considering the complexity of this field, a multidisciplinary approach is necessary with the goal of reducing the incidence of AKI in cancer patients and improving patient outcomes. The overriding research goal in this area is to gather higher quality data from international collaborative studies.

Dual sEH/COX-2 Inhibition Using PTUPB-A Promising Approach to Antiangiogenesis-Induced Nephrotoxicity

Kidney injury from antiangiogenic chemotherapy is a significant clinical challenge, and we currently lack the ability to effectively treat it with pharmacological agents. Thus, we set out to investigate whether simultaneous soluble epoxide hydrolase (sEH) and cyclooxygenase-2 (COX-2) inhibition using a dual sEH/COX-2 inhibitor PTUPB could be an effective strategy for treating antiangiogenic therapy-induced kidney damage. We used a multikinase inhibitor, sorafenib, which is known to cause serious renal side effects. The drug was administered to male Sprague-Dawley rats that were on a high-salt diet. Sorafenib was administered over the course of 56 days. The study included three experimental groups; 1) control group (naïve rats), 2) sorafenib group [rats treated with sorafenib only (20 mg/kg/day p.o.)], and 3) sorafenib + PTUPB group (rats treated with sorafenib only for the initial 28 days and subsequently coadministered PTUPB (10 mg/kg/day i.p.) from days 28 through 56). Blood pressure was measured every 2 weeks. After 28 days, sorafenib-treated rats developed hypertension (161 ± 4 mmHg). Over the remainder of the study, sorafenib treatment resulted in a further elevation in blood pressure through day 56 (200 ± 7 mmHg). PTUPB treatment attenuated the sorafenib-induced blood pressure elevation and by day 56, blood pressure was 159 ± 4 mmHg. Urine was collected every 2 weeks for biochemical analysis. After 28 days, sorafenib rats developed pronounced proteinuria (9.7 ± 0.2 P/C), which intensified significantly (35.8 ± 3.5 P/C) by the end of day 56 compared with control (2.6 ± 0.4 P/C). PTUPB mitigated sorafenib-induced proteinuria, and by day 56, it reduced proteinuria by 73%. Plasma and kidney tissues were collected on day 56. Kidney histopathology revealed intratubular cast formation, interstitial fibrosis, glomerular injury, and glomerular nephrin loss at day 56 in sorafenib-treated rats. PTUPB treatment reduced histological features by 30%-70% compared with the sorafenib-treated group and restored glomerular nephrin levels. Furthermore, PTUPB also acted on the glomerular permeability barrier by decreasing angiotensin-II-induced glomerular permeability to albumin. Finally, PTUPB improved in vitro the viability of human mesangial cells. Collectively, our data demonstrate the potential of using PTUPB or dual sEH/COX-2 inhibition as a therapeutic strategy against sorafenib-induced glomerular nephrotoxicity.

Outcomes of kidney injury including dialysis and kidney transplantation in pediatric oncology and hematopoietic cell transplant patients

Pediatric oncology and hematopoietic cell transplant (HCT) patients are susceptible to both acute kidney injury (AKI) and chronic kidney disease (CKD). The etiologies of AKI vary but include tumor infiltration, radiation, drug-induced toxicity, and fluid and electrolyte abnormalities including tumor lysis syndrome. HCT patients can also have additional complications such as sinusoidal obstructive syndrome, graft-versus-host disease, or thrombotic microangiopathy. For patients with severe AKI requiring dialysis, multiple modalities can be used successfully, although continuous kidney replacement therapy (CKRT) is often the principal modality for critically ill patients. While increasing numbers of pediatric cancer and HCT patients are now surviving long term, they remain at risk for a number of chronic medical conditions, including CKD. Certain high-risk patients, due to underlying risk factors or treatment-related complications, eventually develop kidney failure and may require kidney replacement therapies. Management of co-morbidities and complications associated with kidney failure, including use of erythropoietin for anemia and potential need for ongoing cancer-related treatment while on dialysis, is an additional consideration in this patient population. Kidney transplantation can be successfully performed in pediatric cancer survivors, although additional features such as specific cancer diagnosis and duration of remission should be considered.

The basics of onco-nephrology in the renal clinic

Onconephrology is a rapidly evolving subspecialty that covers all areas of renal involvement in cancer patients. The complexity of the field may benefit from well-defined multidisciplinary management by a dedicated team. Patients with cancer frequently suffer from concurrent chronic kidney disease (CKD), with a prevalence ranging from 12% to 53% at the time of cancer diagnosis. Taking into account the incidence of cancer and the prevalence of CKD in the Italian population, we estimate that about 44,000 patients suffered from both diseases in 2020. Since there is an increasing necessity to address the needs of this population in dedicated outpatient clinics, it is critical to highlight some basic characteristics and to suggest areas of development. Our experience in the nephrological management of cancer patients clearly suggests the need to implement dedicated multidisciplinary teams and to create onconephrology clinics (at least within larger, referral, hospitals). Furthermore, it must be kept in mind that not only is CKD common in cancer patients, but also that the concomitant presence of these two conditions too often excludes cancer patients from clinical trials, thus limiting their access to therapies that could potentially improve their outcomes. Indeed, the Renal Insufficiency and Cancer Medications (IRMA) study found that cancer patients with CKD or on dialysis are often undertreated, or are exposed to either ineffective or toxic anticancer agents. Finally, the aim of this article is to initiate a debate about what an onconephrology outpatient clinic might look like, in order to ensure the highest quality of care for this growing patient population.

The Link Between Conventional and Novel Anti-Cancer Therapeutics with Thrombotic Microangiopathy

BACKGROUND

Kidney disease associated with cancer and anti-cancer therapies has been increasingly recognized in the field of onco-nephrology. In particular, drug-induced nephrotoxicity has important implications since most chemotherapeutic agents have a nephrotoxic potential. Also, standard creatinine clearance methods used for the measurement of kidney function have been questioned in cancer patients due to factors like low muscle mass and poor nutritional status. Overestimations of the glomerular filtration rate, not only can increase the nephrotoxic potential of different agents, but also further limit the use of first-line therapies.

OBJECTIVE

This review covers specifically the drug-induced thrombotic microangiopathy and its two pathophysiologic mechanisms which include immune or idiosyncratic reactions, and non-immune or dose-dependent ones.

CONCLUSION

As novel cancer therapies are developed, it is paramount to pursue a better understanding of conventional and novel chemotherapeutic agents and their role in kidney disease.

Renal toxicity of targeted therapies for renal cell carcinoma in patients with normal and impaired kidney function

The introduction of novel targeted therapies during the last 2 decades has led to a significant improvement in patients' clinical outcomes with renal cell carcinoma. However, this improvement came at the price of a whole new spectrum of adverse events, including renal toxicity. Systemic treatment of patients with kidney neoplasms who often present with impairment of kidney function, even prior to treatment, poses an increasing diagnostic and therapeutic challenge for clinicians. Common lifestyle-related comorbidities, i.e., hypertension and diabetes, may contribute to further impairment of kidney function. The lack of official guidelines and the exclusion of patients with reduced kidney function from the clinical trials of recently approved drugs complicate the issue even further. Early detection and correct management of renal toxic effects are crucial to preserve kidney function and ensure the optimal administration of life-prolonging therapies. This review presents detailed information on the renal toxicities of three groups of drugs commonly used in renal cell carcinoma treatment: tyrosine kinase inhibitors, mammalian target of rapamycin inhibitors, and immune checkpoint inhibitors. We outline the incidence and underlying mechanisms of renal adverse effects with a focus on patients on renal replacement therapy, as well as present suggestions for their management.

Lenvatinib-related renal microangiopathy: a case series

Tyrosine kinase inhibitors play an important role in the armamentarium against cancer. Lenvatinib is a multiple kinase inhibitor approved by the Food and Drugs Administration (FDA) for the treatment of advanced and radioresistant thyroid carcinomas and, in combination with everolimus, for renal cell carcinoma and unresectable hepatocellular carcinoma. The anti-tumoral activity is largely dependent on inhibition of neo-angiogenesis, and established side effects of anti-angiogenetic therapeutics include renal thrombotic microangiopathy (TMA). Here, we describe three cases of biopsy-proven renal TMA clinically presenting with proteinuria and stable serum creatinine in patients receiving lenvatinib for thyroid cancer. Microangiopathic lesions included glomerular basement membrane reduplication with segmental cellular interposition, mesangiolysis, and focal intracapillary and arteriolar thrombi. Drug-dose reduction or withdrawal was effective in renal function preservation, but cancer progressed in all patients. The management of lenvatinib-induced renal TMA remains a challenge. The best therapy in these patients is still uncertain. Earlier and more precise measurement of urine protein levels, allowing for early dose adjustment, could be effective in preventing further damage and drug discontinuation.

Therapeutic Potentials of Selected Antihypertensive Agents and Their Fixed-Dose Combinations Against Trastuzumab-Mediated Cardiotoxicity

Trastuzumab (TZM) is useful in the clinical management of HER2-positive metastatic breast, gastric, and colorectal carcinoma but has been limited by its off-target cardiotoxicity. This study investigates the therapeutic potentials of 0.25 mg/kg/day amlodipine, 0.035 mg/kg/day lisinopril, 5 mg/kg/day valsartan, and their fixed-dose combinations in TZM-intoxicated Wistar rats that were randomly allotted into 10 groups of 6 rats for each group. Group I rats were treated with 10 ml/kg/day sterile water orally and 1 ml/kg/day sterile water intraperitoneally; Groups II, III, and IV rats were orally gavaged with 5 mg/kg/day valsartan and 1 ml/kg/day sterile water intraperitoneally, 0.25 mg/kg/day amlodipine and 1 ml/kg/day sterile water via the intraperitoneal route, 0.035 mg/kg/day lisinopril and 1 ml/kg/day sterile water administered intraperitoneally, respectively. Group V rats were orally treated with 10 ml/kg/day of sterile water prior to intraperitoneal administration of 2.25 mg/kg/day of TZM. Groups VI–VIII rats were equally pretreated with 5 mg/kg/day valsartan, 0.25 mg/kg/day amlodipine, and 0.035 mg/kg/day lisinopril before intraperitoneal 2.25 mg/kg/day TZM treatment, respectively; Groups IX and X rats were orally pretreated with the fixed-dose combinations of 0.25 mg/kg/day amlodipine +0.035 mg/kg/day lisinopril and 5 mg/kg/day valsartan +0.035 mg/kg/day lisinopril, respectively, before TZM treatment. Cardiac injury and tissue oxidative stress markers, complete lipids profile, histopathological, and immunohistochemical assays were the evaluating endpoints. Results showed that repeated TZM treatments caused profound increases in the serum TG and VLDL-c levels, serum cTnI and LDH levels, and cardiac tissue caspase-3 and -9 levels but decreased BCL-2 expression. TZM also profoundly attenuated CAT, SOD, GST and GPx activities, and increased MDA levels in the treated tissues. In addition, TZM cardiotoxicity was characterized by marked vascular and cardiomyocyte congestion and coronary artery microthrombi formation. However, the altered biochemical, histopathological, and immunohistochemical changes were reversed with amlodipine, lisinopril, valsartan, and fixed-dose combinations, although fixed-dose valsartan/lisinopril combination was further associated with hyperlipidemia and increased AI and CRI values and coronary artery cartilaginous metaplasia. Thus, the promising therapeutic potentials of amlodipine, lisinopril, valsartan and their fixed-dose combinations in the management of TZM cardiotoxicity, majorly mediated via antiapoptotic and oxidative stress inhibition mechanisms were unveiled through this study.

Acylated ghrelin protects against doxorubicin-induced nephropathy by activating silent information regulator 1

This study investigated the nephroprotective role of acylated ghrelin (AG) against DOX-induced nephropathy and examined whether the protection involves silent information regulator 1 (SIRT1). Rats were divided into control, control + AG, DOX, DOX + AG, DOX + AG + [D-Lys3]-GHRP-6 (a ghrelin receptor antagonist), and DOX + AG + EX-527 (a sirt1 inhibitor). DOX was given over the first 2 weeks. AG (10 ng/kg) and both inhibitors were given as 3 doses/wk for 5 weeks. AG improved the structure and the function of the kidneys; down-regulated the renal expression of TGF-β1, collagen 1A1 and α-SMA; and inhibited the renal collagen deposition in the kidneys of DOX-treated rats. Concomitantly, it reduced the renal levels of ROS, MDA, TNF-α, and IL-6 and protein levels of cytochrome-c, TGF-β1, Smad3 and α-SMA in these rats. In both the control and DOX-treated rats, AG significantly increased the renal levels of SOD and GSH, decreased the expression of cleaved caspase-3 and Bax, increased the total levels and the nuclear activity of SIRT1 and reduced the deacetylation of p53, NF-κB and FOXO-31. All the effects were abolished by the concurrent administration of EX-527 and [D-Lys3]-GHRP-6. In conclusion, AG prevents DOX-induced nephropathy in SIRT1 and GSHRa1-dependent mechanism.

Clinical Significance of Acute Kidney Injury in Lung Cancer Patients

Purpose

Acute kidney injury (AKI) in cancer patients is associated with increased morbidity and mortality. The incidence of AKI in lung cancer seems to be relatively higher compared with other solid organ malignancies, although its impact on patient outcomes remains unclear.

Materials and Methods

The patients newly diagnosed with lung cancer from 2004 to 2013 were enrolled in this retrospective cohort study. The patients were categorized according to the presence and severity of AKI. We compared all-cause mortality and long-term renal outcome according to AKI stage.

Results

A total of 3,202 patients were included in the final analysis. AKI occurred in 1,783 (55.7%) patients during the follow-up period, with the majority having mild AKI stage 1 (75.8%). During the follow-up of 2.6±2.2 years, total 1,251 patients (53.7%) were died and 5-year survival rate was 46.9%. We found that both AKI development and severity were independent risk factors for all-cause mortality in lung cancer patients, even after adjustment for lung cancer-specific variables including the stage or pathological type. In addition, patients suffered from more severe AKI tend to encounter de novo chronic kidney disease development, worsening kidney function, and end-stage kidney disease progression.

Conclusion

In this study, more than half of the lung cancer patients experienced AKI during their diagnosis and treatment period. Moreover, AKI occurrence and more advanced AKI were associated with a higher mortality risk and adverse kidney outcomes.

Onconephrology: The intersections between the kidney and cancer

Onconephrology is a new subspecialty of nephrology that recognizes the important intersections of kidney disease with cancer. This intersection takes many forms and includes drug-induced nephrotoxicity, electrolyte disorders, paraneoplastic glomerulonephritis, and the interactions of chronic kidney disease with cancer. Data clearly demonstrate that, when patients with cancer develop acute or chronic kidney disease, outcomes are inferior, and the promise of curative therapeutic regimens is lessened. This highlights the imperative for collaborative care between oncologists and nephrologists in recognizing and treating kidney disease in patients with cancer. In response to this need, specific training programs in onconephrology as well as dedicated onconephrology clinics have appeared. This comprehensive review covers many of the critical topics in onconephrology, with a focus on acute kidney injury, chronic kidney disease, drug-induced nephrotoxicity, kidney disease in stem cell transplantation, and electrolyte disorders in patients with cancer.

Kidney Involvement in Patients With Chronic Myelomonocytic Leukemia or BCR-ABL-Negative Myeloproliferative Neoplasms

Introduction

The identification of specific molecular signatures and the development of new targeted drugs have changed the paradigm of onco-nephrology, now allowing a multiscale approach of kidney involvement related to hematologic malignancies relying on combined hematologic and molecular assessments. In this study, we aimed to refine the spectrum of kidney disorders associated with chronic myelomonocytic leukemia (CMML) or BCR-ABL–negative myeloproliferative neoplasms (MPNs), 2 very rare conditions scarcely described.

Methods

Case series. Patients with myeloid neoplasms who were referred to Toulouse University Hospital Nephrology Unit and were diagnosed with acute kidney injury (AKI), chronic kidney disease (CKD), or urine abnormalities were retrospectively included.

Results

Eighteen patients (males n=13, CMML n=8, essential thrombocytosis [ET] n=7, polycythemia vera [PV] n=1, and myelofibrosis n=2) developed kidney disease 7.7±2 years after the diagnosis of the malignancy. Twelve patients had AKI at presentation. Eight patients had glomerular presentation (high-range proteinuria 33%, microscopic hematuria 56%). Kidney biopsy (n=14) showed various patterns, including pauci-immune glomerulosclerosis (n=5), extramedullary hematopoiesis (n=6), or tubular atrophy and interstitial fibrosis with polymorphic inflammation (n=8). Immunostaining of CD61 confirmed the infiltration of megakaryocytes within glomeruli or interstitium in 5 of 8 patients. Other pictures of glomerulopathy were identified in 3 patients (IgA nephropathy n=2, AA amyloidosis n=1). Massive kidney infiltration by CMML was identified in 1 patient. After a mean follow-up of 24±6 months, malignancy was considered as stable in 11 patients (61%), but 22% of patients had progressed to end-stage renal failure. The remaining had persistently reduced kidney function. No correlation between the malignancy and the renal presentation and outcomes could be identified.

Conclusions

Kidney complications of CMML/MPN are heterogenous, and kidney biopsy may help to identify new molecular targets to prevent the development of kidney fibrosis.

Renal and Hepatic Health After Childhood Cancer

Childhood cancer survivors (CCSs) are at risk for renal and hepatic complications related to curative cancer treatments. Although acute renal and hepatic toxicities of cancer treatments are well described, data regarding long-term and late-occurring sequelae or their associations with acute sequelae are less robust. This article highlights the literature on the prevalence of and risk factors for late renal and hepatic toxicity in CCSs. Studies investigating these outcomes are needed to inform surveillance practices and the development of future frontline cancer treatment protocols.

Preventive strategies for acute kidney injury in cancer patients

Acute kidney injury (AKI) is a common complication of cancer that occurs in up to 50% of neoplastic patients during the natural history of their disease; furthermore, it has a huge impact on key outcomes such as overall prognosis, length of hospitalization and costs. AKI in cancer patients has different causes, either patient-, tumour- or treatment-related. Patient-related risk factors for AKI are the same as in the general population, whereas tumour-related risk factors are represented by compression, obstruction, direct kidney infiltration from the tumour as well by precipitation, aggregation, crystallization or misfolding of paraprotein (as in the case of multiple myeloma). Finally, treatment-related risk factors are the most common observed in clinical practice and may present also with the feature of tumour lysis syndrome or thrombotic microangiopathies. In the absence of validated biomarkers, a multidisciplinary clinical approach that incorporates adequate assessment, use of appropriate preventive measures and early intervention is essential to reduce the incidence of this life-threatening condition in cancer patients.

KDIGO Controversies Conference on onco-nephrology: understanding kidney impairment and solid-organ malignancies, and managing kidney cancer

The association between kidney disease and cancer is multifaceted and complex. Persons with chronic kidney disease (CKD) have an increased incidence of cancer, and both cancer and cancer treatments can cause impaired kidney function. Renal issues in the setting of malignancy can worsen patient outcomes and diminish the adequacy of anticancer treatments. In addition, the oncology treatment landscape is changing rapidly, and data on tolerability of novel therapies in patients with CKD are often lacking. Caring for oncology patients has become more specialized and interdisciplinary, currently requiring collaboration among specialists in nephrology, medical oncology, critical care, clinical pharmacology/pharmacy, and palliative care, in addition to surgeons and urologists. To identify key management issues in nephrology relevant to patients with malignancy, KDIGO (Kidney Disease: Improving Global Outcomes) assembled a global panel of multidisciplinary clinical and scientific expertise for a controversies conference on onco-nephrology in December 2018. This report covers issues related to kidney impairment and solid organ malignancies as well as management and treatment of kidney cancer. Knowledge gaps, areas of controversy, and research priorities are described.

Impact of acute kidney injury on anticancer treatment dosage and long-term outcomes: a pooled analysis of European Organisation for Research and Treatment of Cancer trials

BACKGROUND

The impact of kidney dysfunction on long-term outcomes of patients with advanced cancer remains unclear.

METHODS

Patients with advanced cancer included in trials conducted by the European Organisation for Research and Treatment of Cancer were eligible for this retrospective analysis. Acute kidney injury (AKI) was identified using serum creatinine levels and using adverse events reported by investigators. The impact of baseline estimated glomerular filtration rates (eGFRs) on progression-free survival (PFS) and overall survival (OS) was investigated. Pooled estimates of the impact of AKI on dose intensity, treatment duration, PFS and OS were obtained following a meta-analytic process.

RESULTS

Nine trials were included in this study, totalling 2872 metastatic patients with various tumour types and various systemic treatment types. Baseline eGFR had homogeneously no impact on PFS or OS. Most Risk, Injury, Failure, Loss of kidney function and End-stage kidney disease (RIFLE) events occurred early during the course of the treatment. AKI was not associated with an increased rate of treatment discontinuation, while it decreased the study treatment dose intensity. Occurrence of a first RIFLE event significantly and homogeneously reduced PFS (pooled hazard ratio = 1.18, 95% confidence interval 1.07-1.30; P = 0.0012), while its impact on OS was more heterogeneous across trials.

CONCLUSION

AKI is associated with reduced treatment dose intensity and reduced PFS. Therefore, close monitoring of the kidney function during the first months of treatment should be included in clinical trial protocols and probably also in daily practice to enable early AKI diagnosis and management. Collaboration between oncologists and nephrologists is needed to reduce the risk of undertreatment of patients experiencing AKI.

Acute kidney injury from contrast-enhanced CT procedures in patients with cancer: white paper to highlight its clinical relevance and discuss applicable preventive strategies

Patients with cancer are subjected to several imaging examinations which frequently require the administration of contrast medium (CM). However, it has been estimated that acute kidney injury (AKI) due to the injection of iodinated CM accounts for 11% of all cases of AKI, and it is reported in up to 2% of all CT examinations. Remarkably, the risks of developing AKI are increased in the elderly, in patients with chronic kidney disease or diabetes, and with dehydration or administration of nephrotoxic chemotherapeutics. Given the common occurrence of postcontrast acute kidney injury (PC-AKI) in clinical practice, primary care physicians and all specialists involved in managing patients with cancer should be aware of the strategies to reduce the risk of this event. In 2018, a panel of four experts from the specialties of radiology, oncology and nephrology were speakers at the annual meeting of the Italian Society of Medical Radiology (Società Italiana di Radiologia Medica e Interventistica), with the aim of commenting on existing evidence and providing their experience on the incidence and management of PC-AKI in patients with cancer. The discussion represented the basis for this white paper, which is intended to be a practical guide organised by statements describing methods to reduce renal injury risks related to CM-enhanced CT examinations in patients with cancer.

Acute kidney injury in cancer patients

The increasing prevalence of neoplasias is associated with new clinical challenges, one of which is acute kidney injury (AKI). In addition to possibly constituting a clinical emergency, kidney failure significantly interferes with the choice and continuation of antineoplastic therapy, with prognostic implications in cancer patients. Some types of neoplasia are more susceptible to AKI, such as multiple myeloma and renal carcinoma. In cancer patients, AKI can be divided into pre-renal, renal (intrinsic), and post-renal. Conventional platinum-based chemotherapy and new targeted therapy agents against cancer are examples of drugs that cause an intrinsic renal lesion in this group of patients. This topic is of great importance to the daily practice of nephrologists and even constitutes a subspecialty in the field, the onco-nephrology.

Targeted therapy for solid tumors and risk of hypertension: a meta-analysis of 68077 patients from 93 phase III studies

Objective: Hypertension is a common adverse event with targeted agents in cancer patients and can lead to serious and sometimes lethal cardiovascular complications. The authors performed a meta-analysis of clinical trials aiming to evaluate the incidence and Relative Risk (RR) of developing all-grade and high-grade Hypertension Events (HE) in patients with solid tumors receiving targeted therapy.Methods: A review of citations from PubMed was performed and studies were selected based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The search was limited to randomized phase III trials published in English focused on the efficacy and safety of targeted agents in cancer patients, reporting data on HE. Incidence, RR and relative 95% CIs were analyzed using random or fixed-effects models. Overall incidences were calculated and further compared with the chi-squared test for proportions.Results: Ninety-three phase III trials were included, with a total of 68,077 patients. Prostate cancer was the most represented (18.9%), followed by breast cancer (17.3%) and colorectal cancer (16.4%). The incidence of all- and high-grade HE was 23.47% and 8.57%, respectively, with the highest incidence of serious HE reported by adjuvant Sunitib/Sorafenib (29.03%). The highest RR of high-grade HE was observed with Bevacizumab in patients with advanced cervical cancer. By drug category, the highest RR of high-grade HE was reported by VEGFR/EGFR TKIs.Conclusion: According to these data, monitoring this class of toxicities is of primary importance to avoid hypertension worsening and, thus, the risk of major cardiovascular events.

Acute kidney injury in the patient with cancer

Dramatic advances in the care of patients with cancer have led to significant improvement in outcomes and survival. However, renal manifestations of the underlying cancer as well as the effects of anti-neoplastic therapies leave patients with significant morbidity and chronic kidney disease risks. The most common renal manifestations associated with cancer include acute kidney injury (AKI) in the setting of multiple myeloma, tumor lysis syndrome, post-hematopoietic stem cell therapy, and AKI associated with chemotherapy. Knowledge of specific risk factors, modification of risk and careful attention to rapid AKI diagnosis are critical for improving outcomes.

Endothelial ERK1/2 signaling maintains integrity of the quiescent endothelium

The endothelial ERK1/2 pathway plays a crucial role in the maintenance of endothelial homeostasis. Its suppression results in activation of TGFβ signaling, leading to hypertension, renal failure, fibrosis, and sudden death, findings similar to those observed in patients treated with anti-VEGF agents.

To define the role of ERK1/2 signaling in the quiescent endothelium, we induced endothelial Erk2 knockout in adult Erk1^−/− mice. This resulted in a rapid onset of hypertension, a decrease in eNOS expression, and an increase in endothelin-1 plasma levels, with all mice dying within 5 wk. Immunostaining and endothelial fate mapping showed a robust increase in TGFβ signaling leading to widespread endothelial-to-mesenchymal transition (EndMT). Fibrosis affecting the cardiac conduction system was responsible for the universal lethality in these mice. Other findings included renal endotheliosis, loss of fenestrated endothelia in endocrine organs, and hemorrhages. An ensemble computational intelligence strategy, comprising deep learning and probabilistic programing of RNA-seq data, causally linked the loss of ERK1/2 in HUVECs in vitro to activation of TGFβ signaling, EndMT, suppression of eNOS, and induction of endothelin-1 expression. All in silico predictions were verified in vitro and in vivo. In summary, these data establish the key role played by ERK1/2 signaling in the maintenance of vascular normalcy.

Oncology in nephrology comes of age: A focus on chronic dialysis patients

Dialysis is the commonest modality of renal replacement therapy for patients suffering from end-stage kidney disease. Different registry studies showed that the risks of overall cancer occurrence were significantly higher in chronic dialysis patients than in the age-matched general population. However, the frequency and pattern of different cancers may vary among different geographical areas. Since chronic dialysis patients tend to have multiple comorbidities and a shorter life expectancy, routine cancer screening in all dialysis patients may not be cost-effective; rather screening should be personalized according to the patient's expected survival, candidacy for kidney transplant together with patient preferences.

Bacteriocins: perspective for the development of novel anticancer drugs

Antimicrobial peptides (AMPs) from prokaryotic source also known as bacteriocins are ribosomally synthesized by bacteria belonging to different eubacterial taxonomic branches. Most of these AMPs are low molecular weight cationic membrane active peptides that disrupt membrane by forming pores in target cell membranes resulting in cell death. While these peptides known to exhibit broad-spectrum antimicrobial activity, including antibacterial and antifungal, they displayed minimal cytotoxicity to the host cells. Their antimicrobial efficacy has been demonstrated in vivo using diverse animal infection models. Therefore, we have discussed some of the promising peptides for their ability towards potential therapeutic applications. Further, some of these bacteriocins have also been reported to exhibit significant biological activity against various types of cancer cells in different experimental studies. In fact, differential cytotoxicity towards cancer cells as compared to normal cells by certain bacteriocins directs for a much focused research to utilize these compounds as novel therapeutic agents. In this review, bacteriocins that demonstrated antitumor activity against diverse cancer cell lines have been discussed emphasizing their biochemical features, selectivity against extra targets and molecular mechanisms of action.

Proteinuria and Renal Dysfunction after Intravitreal Injection of Bevacizumab in Patients with Diabetic Nephropathy: A Prospective Observational Study

Background:

Proliferative diabetic retinopathy (PDR) is one of the most important microvascular complications among the patients with diabetes. Intravitreal anti-vascular endothelial growth factor (anti-VEGF) agent enacts a key role in PDR. Some studies have dealt with the systemic exposure to these agents after intravitreal administration. However, renal dysfunction following this therapy has scarcely been reported. Hence, this study aimed to determine the effect of intravitreal bevacizumab treatment on the deterioration of renal function and proteinuria.

Materials and Methods:

This present prospective observational study was performed on 40 patients with diabetic nephropathy and PDR and/or significant diabetic macular edema as the candidates for receiving intravitreal injection of bevacizumab. To evaluate renal function, changes in the urinary albumin-to-creatinine ratio (UACR), serum creatinine (SCr), and estimated glomerular filtration rate (eGFR) one month after injection were measured. Also, changes in systolic and diastolic blood pressures (BPs), plasma VEGF level, platelet, white blood cell (WBC) counts, and hemoglobin (Hb) level were measured at the baseline and one month after treatment.

Results:

The mean age of the patients was 60.3 ± 9.2 years, and 33 patients were female. The decrease in the plasma VEGF level and platelet count, as well as the increase in diastolic BP, and Hb level were significant. However, systolic BP and WBC count remained unchanged. There were no significant changes in UACR, SCr, and eGFR after the injection as compared to baseline (P>0.05).

Conclusion:

Our study indicated that intravitreal bevacizumab injection was not associated with renal dysfunction and proteinuria in patients with diabetic nephropathy. Nevertheless, diastolic BP and Hb level could increase after one month.

Nephrotoxicity of Cancer Immunotherapies: Past, Present and Future

Nephrotoxicity from cancer therapies is common and increasingly encountered in clinical practice, such that the subfield of "onco-nephrology" has emerged. Conventional chemotherapeutic drugs and novel agents targeting specific genes/proteins are effective cancer therapies but suffer from a number of adverse kidney effects. An effective avenue of cancer treatment is immunotherapy, which uses drugs that augment immune system-mediated recognition and targeting of tumor cells. As such, leveraging the immune system to target malignant cells represents an important modality in eradicating cancer. IFN and high-dose IL-2 are older immunotherapies used in clinical practice to treat various malignancies, whereas new cancer immunotherapies have emerged over the past decade that offer even more effective treatment options. The immune checkpoint inhibitors are an exciting addition to the cancer immunotherapy armamentarium. Chimeric antigen receptor T cells are also a new immunotherapy used to treat various hematologic malignancies. However, as with the conventional and targeted cancer agents, the immunotherapies are also associated with immune-related adverse effects, which includes nephrotoxicity.