[Cancer imaging and prevention of renal failure]

The risk of acute renal failure (ARF) following iodinated contrast media injection has long been overestimated because of the previous use of more toxic ICPs and uncontrolled studies. Nowadays, this concept is being questioned. Patients with severe renal failure and/or ARF are the only group still considered at risk. In these patients, it is necessary to discuss an alternative without an iodinated contrast agent. Contrast-enhanced ultrasound, MRI, spectral CT or PET-CT scan can be used instead of contrast-enhanced CT. Preventive measures should be applied when appropriate substitute to CT is not available or not diagnosed (minimum necessary dose of ICP, interruption of some treatments and prior hydration). These recommendations formalized by the European Society of Urogenital Radiology (ESUR) in 2018 address most situations faced by clinicians. In complex situations, an opinion from a nephrologist remains necessary after asking the radiologist about the availability of acceptable substitutes.

Long-Term Response of Pembrolizumab in a Patient with Metastatic Squamous Non-Small Cell Lung Cancer on Hemodialysis: Case Report and Review of the Literature

In patients with renal failure and hemodialysis, there are difficulties in drug selection and dose adjustment for cancer treatment. The use of immune checkpoint inhibitors (ICIs), including pembrolizumab, approved by the U.S. Food and Drug Administration (FDA) for patients with metastatic non-small cell lung cancer (NSCLC) in 2015, has become an important option for the treatment of metastatic NSCLC. However, data regarding the dosage and schedule for long-term use of ICIs, especially pembrolizumab, in hemodialysis patients are limited. We present the case of a patient with metastatic squamous NSCLC who demonstrated a long-term partial response to pembrolizumab monotherapy for 45 months during hemodialysis and showed no immune-related adverse events (irAEs). To our knowledge, this is the longest remission to be reported without irAEs after discontinuation of pembrolizumab in a NSCLC patient undergoing HD. In addition, we reviewed previously reported lung cancer patients who used ICI during dialysis, comparing them with our case in clinical aspect. We believe that this report will provide clinical insights into the long-term efficacy and safety of pembrolizumab in lung cancer patients undergoing hemodialysis.

Cancer Risk and Mortality in Patients With Kidney Disease: A Population-Based Cohort Study

RATIONALE & OBJECTIVE

Patients with chronic kidney disease (CKD) may be at increased risk for cancer. CKD may also be associated with worse cancer outcomes. This study examined cancer incidence and mortality across the spectrum of CKD.

STUDY DESIGN

Population-based cohort study.

SETTING & PARTICIPANTS

All adult Ontario residents with data on estimated glomerular filtration rate (eGFR) or who were receiving maintenance dialysis or had received a kidney transplant (2007-2016).

EXPOSURE

Patients were categorized as of the first date they had 2 eGFR assessments or were registered as receiving maintenance dialysis or having received a kidney transplant. eGFR levels were further categorized as ≥60, 45-59, 30-44, 15-29, and <15 mL/min/1.73 m²; the latter 4 groups are consistent with KDIGO (Kidney Disease: Improving Global Outcomes) CKD categories G3a, G3b, G4, and G5, respectively.

OUTCOMES

Overall and site-specific cancer incidence and mortality.

ANALYTICAL APPROACH

Fine and Gray subdistribution hazard models.

RESULTS

Among 5,882,388 individuals with eGFR data, 29,809 receiving dialysis, and 4,951 having received a kidney transplant, there were 325,895 cancer diagnoses made during 29,993,847 person-years of follow-up. The cumulative incidence of cancer ranged between 10.8% and 15.3% in patients with kidney disease. Compared with patients with eGFR ≥60 mL/min/1.73 m², adjusted hazard ratios (AHRs) for a cancer diagnosis among patients with CKD G3a, G3b, G4, and G5 were 1.08 (95% CI, 1.07-1.10), 0.99 (95% CI, 0.97-1.01), 0.85 (95% CI, 0.81-0.88), and 0.81 (95% CI, 0.73-0.90), respectively. The AHRs for patients receiving dialysis and who had received a transplant were 1.01 (95% CI, 0.96-1.07) and 1.25 (95% CI, 1.12-1.39), respectively. Patients with kidney disease had higher proportions of stage 4 cancers at diagnosis. Patients with CKD G3a, G3b, and G4 and transplant recipients had increased risks of cancer-specific mortality (AHRs of 1.27 [95% CI, 1.23-1.32], 1.29 [95% CI, 1.24-1.35], 1.25 [95% CI, 1.18-1.33], and 1.48 [95% CI, 1.18-1.87], respectively). The risks of bladder and kidney cancers and multiple myeloma were particularly increased in CKD, and mortality from these malignancies increased with worsening kidney function.

LIMITATIONS

Possible unmeasured confounding and limited ability to infer causal associations.

CONCLUSIONS

Cancer incidence in the setting of kidney disease is substantial. Cancer risk was increased in mild to moderate CKD and among transplant recipients, but not in advanced kidney disease. Cancer-related mortality was significantly higher among patients with kidney disease, particularly urologic cancers and myeloma. Strategies to detect and manage these cancers in the CKD population are needed.

Improving Cancer Care for Patients With CKD: The Need for Changes in Clinical Trials

Chemotherapeutic agents used to treat cancer generally have narrow therapeutic indices along with potentially serious adverse toxicities. Many cancer drugs are at least partially excreted through the kidney and, thus, the availability of accurate data on safe and effective dosing of these drugs in patients with chronic kidney disease (CKD) is essential to guide treatment decisions. Typically, during drug development, initial clinical studies only include patients with normal or only mildly impaired kidney function. In subsequent preregistration studies, a limited number of patients with more severe kidney dysfunction are included. Data obtained from patients with either severe kidney dysfunction (here defined as an estimated glomerular filtration rate [eGFR] < 30 ml/min or stage 4G CKD) or end-stage kidney disease (ESKD) requiring kidney replacement treatment are particularly limited before drug registration and only a minority of new drug applications to the US Food and Drug Administration (FDA) include data from this population. Unfortunately, limited data and/or other safety concerns may result in a manufacturer statement that the drug is contraindicated in patients with advanced kidney disease, which hinders access to potentially beneficial drugs for these patients. This systemic exclusion of patients with CKD from cancer drug trials remains an unsolved problem, which prevents provision of optimal clinical care for these patients, raises questions of inclusion, diversity, and equity. In addition, with the aging of the population, there are increasing numbers of patients with CKD and cancer who face these issues. In this review, we evaluate the scientific basis to exclude patients with CKD from cancer trials and propose a comprehensive strategy to address this problem.

Cancer Drug Dosing in Chronic Kidney Disease and Dialysis

Patients with malignancies have a high prevalence of kidney disease and are often treated with antineoplastic agents that undergo kidney metabolism or excretion or clearance via renal replacement therapies. Thus, the dosing of these agents, including classic chemotherapeutic drugs, targeted therapies, and immunotherapy, must take into account patients' kidney function. In this review, we will discuss the pitfalls of accurate measurement of kidney function and how kidney disease affects both pharmacodynamic and pharmacokinetic properties of drugs. Lastly, we will discuss specific agents and summarize current dosing strategies for use in patients with chronic kidney disease and end-stage kidney disease.

Kidney function and cancer risk: An analysis using creatinine and cystatin C in a cohort study

BACKGROUND

We examined whether an increased risk of cancer incidence and death is associated with kidney function and albuminuria and whether the risk is more readily identified when kidney function is estimated using cystatin C.

METHODS

Participants were from UK Biobank (recruitment spanning 2007-2010), excluding those with a prior diagnosis of cancer. Estimated glomerular filtration rate (ml/min/1.73m2) was calculated using creatinine (eGFRcr), cystatin C (eGFRcys) and creatinine-cystatin C (eGFRcr-cys). Cox proportional hazards models tested associations between eGFR, urinary albumin:creatinine ratio (uACR) and cancer incidence and death.

FINDINGS

In 431,263 participants over median follow-up of 11.3 (IQR 10.6-12.0) years, there were 41,745 incident cancers and 11,764 cancer deaths. eGFRcys was most strongly associated with cancer incidence and death (HR 1.04 (95% CI 1.03-1.04) and 1.06 (1.05-1.07) per 10 ml/min/1.73m2 decline, respectively). eGFRcr was not associated with either outcome (incidence: HR 1.00 (1.00-1.01); death: HR 0.99 (0.98-1.01) per 10 ml/min/1.73m2 decline). Relative to eGFRcys>90 or uACR<3 mg/mmol, eGFRcys60-89 (HR 1.04 (95% CI 1.02-1.07)), eGFRcys<60 (HR 1.19 (1.14-1.24)) and uACR≥3 mg/mmol (HR 1.09 (1.06-1.12)) were associated with higher risk of incident cancer. eGFRcys60-89 (HR 1.15 (1.10-1.21)); eGFRcys<60 (HR 1.48 (1.38-1.59)) and uACR≥3 mg/mmol (HR 1.17 (1.11-1.24)) were associated with cancer death.

INTERPRETATION

Excess risk of cancer incidence and cancer death is more readily captured in early chronic kidney disease by eGFRcys than by current measures. The association between kidney function, uACR and cancer death in particular is concerning and warrants further scrutiny.

FUNDING

Chief Scientist Office; ANID Becas Chile; Medical Research Council; British Medical Association; British Heart Foundation.

Defining cisplatin eligibility in patients with muscle-invasive bladder cancer

The current treatment paradigm for muscle-invasive bladder cancer (MIBC) consists of cisplatin-based neoadjuvant chemotherapy followed by local definitive therapy, or local definitive therapy alone for cisplatin-ineligible patients. Given that MIBC has a high propensity for distant relapse and is a chemotherapy-sensitive disease, under-utilization of chemotherapy is associated with suboptimal cure rates. Cisplatin eligibility criteria are defined for patients with metastatic bladder cancer by the Galsky criteria, which include creatinine clearance ≥60 ml/min. However, consensus is still lacking regarding cisplatin eligibility criteria in the neoadjuvant, curative MIBC setting, which continues to represent a substantial barrier to the standardization of patient care and clinical trial design. Jiang and colleagues accordingly suggest an algorithm for assessing cisplatin eligibility in patients with MIBC. Instead of relying on an absolute renal function threshold, their algorithm emphasizes a multidisciplinary and patient-centred approach. They also propose mitigation strategies to minimize the risk of cisplatin-induced nephrotoxicity in selected patients with impaired renal function. This new framework is aimed at reducing the inappropriate exclusion of some patients from cisplatin-based neoadjuvant chemotherapy (which leads to under-treatment) and harmonizing clinical trial design, which could lead to improved overall outcomes in patients with MIBC.

Drug dosing in cancer patients with decreased kidney function: A practical approach

Correct drug dosing of anticancer agents is essential to obtain optimal outcomes. Overdosing will result in increased toxicity, treatment interruption and possible cessation of anticancer treatment. Underdosing may result in suboptimal anti-cancer effects and may increase the risk of cancer-related mortality. As it is practical nor feasible to perform therapeutic drug monitoring for all anti-cancer drugs, kidney function is used to guide drug dosing for those drugs whose primary mode of excretion is through the kidney. However, it is not well-established what method should be utilized to measure or estimate kidney function and the choice of method does influence treatment decisions regarding eligibility for anti-cancer drugs and their dose. In this review, we will provide an overview regarding the importance of drug dosing, the preferred method to determine kidney function and a practical approach to drug dosing of anticancer drugs.

Administration of iodinated contrast: What is the risk in cancer patients?

OBJECTIVE

Despite the association between intravenous contrast and kidney injury, few studies exist in oncology. Our objective was to estimate kidney outcomes following iodinated contrast-enhanced computed tomography (CECT) in cancer patients, and to evaluate whether self-assessment questionnaires can identify kidney injury risk factors.

METHODS

This prospective observational study included 289 patients who underwent a CECT scan between March and May 2017 in a hospital setting. All patients completed the modified European Society of Urogenital Radiology (ESUR) questionnaire and had an estimated glomerular filtration rate (eGFR) >30 ml/min/1.73 m² on the day of the examination. Outcomes were followed for 4 months. Univariate and logistic regression analyses were carried out.

RESULTS

In the logistic regression analysis, the only variables statistically associated with deterioration in the eGFR were age, (odds ratio (OR) = 1.091, p = 0.003), female sex, (OR 0.22, p = 0.020) and arterial hypertension (AH), (OR = 3.57, p = 0.019). Regarding exitus, only the group with a worse eGFR was close to predictive statistical significance (OR = 2.48, p = 0.09).

CONCLUSIONS

The administration of iodinated contrast in cancer patients was not associated with an increase in kidney outcomes. Risk factors in these patients were age, sex and AH.

How to determine kidney function in cancer patients?

A precise and efficient method for estimating kidney function in cancer patients is important to determine their eligibility for clinical trials and surgery and to allow for appropriate dose adjustment of anti-cancer drugs, especially toxic drugs with a narrow therapeutic index. Since direct measurement of glomerular filtration rate (GFR) is cumbersome, several formulae have been developed to estimate kidney function. Most of these are based on serum creatinine concentration. Though the CKD-EPI formula is recognised as being the most accurate, there is an ongoing debate on which is the optimal formula for cancer patients. In this review, we provide an overview of different GFR estimating equations for kidney function and the advantages and disadvantages of each method and compare their performance in cancer patients. We discuss the importance of body surface area-indexing and propose a framework for evaluating kidney function in cancer patients.