Cancer Screening in End-Stage Kidney Disease

Tumor characteristics in immunosuppressed and renal dysfunction populations

PURPOSE

Renal transplantation and end-stage renal disease are increasingly common. Renal dysfunction and immunosuppression are two risk factors in the development of renal cell carcinoma. Carcinomas in these patients are thought to be more indolent, however data are limited and mixed. Our objective was to describe the histology of resected tumors from the transplant and renal dysfunction population and compare them to a control population.

MATERIALS AND METHODS

This was a single-center retrospective cohort study of all patients who had a nephrectomy for a renal mass from 2009 to 2019. All transplant status and end-stage renal disease diagnoses were identified by diagnostic or procedural coding and confirmed by chart review. Our primary endpoint was the pathology for each patient's tumor. Tumors were classified into aggressive or nonaggressive categories based on their histology and grade.

RESULTS

We identified 1,150 radical and partial nephrectomies, of which 1,057 met inclusion criteria. Of these, 68 patients (6.4%) had renal dysfunction or a kidney transplant on immunosuppression at time of nephrectomy. After pathologic review, 270 (25%) tumors were classified as aggressive, and 673 (64%) tumors were pT1a or pT1b. On multivariable logistic regression controlling for age and gender, renal dysfunction was not associated with having an aggressive tumor (OR 1.24, 95%CI 0.72-2.15; P = 0.44).

CONCLUSIONS

We did not observe a relationship between renal dysfunction status and aggressive pathology. These data suggest that renal dysfunction and transplant patients are at similar risk for aggressive pathology as the general population and should be managed according to the same clinical guidelines.

Cancer Incidence and Mortality Patterns in Hemodialysis Patients: A Descriptive Study

Background End-stage renal disease (ESRD) is a condition where the kidneys cease functioning, requiring renal replacement therapy such as dialysis. ESRD patients face numerous health challenges, including an elevated risk of developing malignancies. Factors contributing to this increased cancer risk include immune suppression, chronic inflammation, DNA repair deficiencies, and chronic viral infections. Objective This study aimed to describe the incidence and characteristics of malignancies, as well as associated risk factors, in patients undergoing hemodialysis. Methods This retrospective descriptive study included all patients receiving dialysis at the dialysis unit of our institution between 2012 and 2022 who were diagnosed with cancer. Cancer incidence and clinical characteristics were analyzed within this patient group. Results Out of 584 patients who underwent dialysis, 11 patients (2%) were diagnosed with cancer. The mean age of cancer patients was 76.5 years. Males accounted for 73% (n=8) of cancer cases. The most common malignancies identified were colorectal carcinoma (28%, n=3) and lung carcinoma (27%, n=3). Conclusion This study highlights the incidence of malignancies among ESRD patients on hemodialysis. Regular monitoring and early detection of malignancies in this high-risk population are crucial for improving outcomes.

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.

Association of estimated glomerular filtration rate with prostate cancer risk in a cross-ethnic population: a Mendelian randomization study

OBJECTIVE

To investigate whether a causal relationship exists between the estimated glomerular filtration rate (EGFR) and the occurrence of prostate cancer in East Asian and European populations and to determine if genetic factors influence the association between the EGFR and prostate cancer risk.

METHODS

In this Mendelian randomization study, the existence of a causal relationship between the EGFR and prostate cancer occurrence was assessed using five analytical techniques, including Mendelian randomization-Egger regression (MR-Egger), calculation of the weighted median estimator (WME), the maximum likelihood ratio method, the linear median weighting method and the random-effects inverse-variance weighting (IVW) method.

RESULTS

In the IVW model, no causal relationship was observed between the EGFR and prostate cancer in either the East Asian or European populations.

CONCLUSIONS

After excluding confounding factors and reverse causal associations using two-sample Mendelian randomization, unbiased estimates were obtained, and there was no causal relationship between prostate cancer and the EGFR in the East Asian or European populations. Therefore, for patients with suspected prostate cancer, it is considered unnecessary to improve the detection of glomerular filtration rate, which will effectively reduce the economic burden of patients.

The potential association between influenza vaccination and lower incidence of renal cell carcinoma

It is well-established that kidney cancer or renal cell carcinoma (RCC) occurs more commonly in chronic kidney disease (CKD) than in the general population, although the underlying mechanisms are incompletely understood. Beyond hereditary RCC syndromes; smoking, obesity and hypertension are widely known risk factors for RCC, irrespective of CKD. Kidney-specific factors such as episodes of acute kidney injury, nephrolithiasis and cyst formation have also been shown to be associated with RCC development. One potential and less explored factor is the role of viruses in the development of kidney cancer. In this issue of Clinical Kidney Journal, Lin et al. raise the interesting hypothesis that influenza vaccination may be associated with lower incidence of RCC in adults with CKD. We discuss potential mechanisms underlying this interesting observation in the context of immune dysregulation in CKD.

Investigation of XPD, miR-145 and miR-770 expression in patients with end-stage renal disease

BACKGROUND

The effective maintenance of genome integrity and fidelity is vital for the normal function of our tissues and organs, and the prevention of diseases. DNA repair pathways maintain genome stability, and the adequacy of genes acting in these pathways is essential for disease suppression and direct treatment responses. Chronic kidney disease is characterized by high levels of genomic damage. In this study, we examined the expression levels of the xeroderma pigmentosum group D (XPD) gene, which plays a role in the nucleotide excision repair (NER) repair mechanism, and the expression levels of miR-145 and miR-770 genes, which play a role in the regulation of the expression of the XPD gene, in hemodialysis patients with (n = 42) and without malignancy (n = 9) in pre- and post-dialysis conditions. We also evaluated these values with the clinical findings of the patients.

METHODS & RESULTS

Gene expression analysis was performed by real-time polymerase chain reaction (qRT-PCR). Compared to the individuals with normal kidney function (2.06 ± 0.32), the XPD gene expression was lower in the pre-dialysis condition both in hemodialysis patients without cancer (1.24 ± 0.18; p = 0.02) and in hemodialysis patients with cancer (0.82 ± 0.114; p = 0.001). On the other hand, we found that miR-145 and miR-770 expression levels were high in both groups. We also found that expression levels were affected by dialysis processes. A statistically significant positive correlation was found between miR-145 and mir770 expression levels in the pre-dialysis group of patients with (r=-0.988. p = 0.0001) and without (r=-0.934. p = 0.0001) malignancy.

CONCLUSIONS

Studies on DNA damage repair in the kidney will help develop strategies to protect kidney function against kidney diseases.