Renal Cell Carcinoma in Transplant Recipients with Acquired Cystic Kidney Disease

Renal cell carcinoma and upper tract urothelial carcinoma in kidney transplant recipients

Renal cell carcinoma (RCC) is the most common solid-organ malignancy in Western countries, and upper tract urothelial carcinoma (UTUC) is the most common malignancy in Asian countries. The management of RCC/UTUC in kidney transplant recipients is complex and clinically challenging due to post-transplant modifications associated with immunosuppressive treatment. This retrospective study evaluated the incidence, risk factors, treatment outcomes, and oncological implications of RCC and UTUC in kidney transplant recipients from 2008 to 2023. Data were collected from clinical records, and follow-up calls for 20 patients diagnosed with RCC and UTUC among 2,283 kidney transplant recipients, revealing an incidence rate of 0.78% for RCC (18 patients) and 0.087% (two patients) for UTUC. Most patients presented localized disease at diagnosis. Surgical interventions included radical nephrectomy for the native kidney's RCC, radical or partial nephrectomy for allograft RCC, and radical nephroureterectomy for UTUC in the native kidney and allograft. Oncological outcomes indicated a mean follow-up of 51.29 months, during which five patients (25%) developed metastases, which achieved prolonged survival through surgical management, adjuvant therapy, and immunosuppression adjustments. The study highlights the increased cancer risk in this population and underscores the necessity for established screening protocols and individualized treatment strategies to optimize patient outcomes while preserving kidney function. These findings contribute to the ongoing research on managing malignancies in transplant recipients, with implications for further research and clinical guidelines.

Comparing surgical outcomes between robot-assisted laparoscopic and open partial nephrectomy for allograft kidney tumors: a retrospective, single-center study

BACKGROUND

Kidney transplantation is considered the best long-term option for patients with end-stage renal disease; however, immunosuppression increases the risk of developing malignancies. Approximately 0.2-0.5% of kidney transplant recipients experience renal cell carcinoma (RCC) in their allografts. Recently, nephron-sparing surgery has become widely accepted because of its favorable survival outcomes and low risk of recurrence.

METHODS

In this study, we retrospectively evaluated the peri- and postoperative outcomes of robot-assisted partial nephrectomy (RAPN) and open partial nephrectomy (OPN) for allograft RCC, analyzing five and six patients who underwent OPN and RAPN, respectively, from 1998 to 2023.

RESULTS

The estimated blood loss was significantly lower in the RAPN group than in the OPN group (6.5 mL [interquartile range (IQR): 1-15] vs. 350 mL [IQR: 139-560], P = 0.006), whereas the operative and renal arterial clamping times were similar. Additionally, the perioperative complication rate and severity were lower in the RAPN group, resulting in a significantly shorter postoperative hospital stay than the OPN group (3 days [IQR: 2-5] vs. 10 days [IQR: 8-12], P = 0.01). Postoperative renal function and oncological outcomes were similar between the two groups.

CONCLUSIONS

RAPN for allograft RCC demonstrated advantages in terms of estimated blood loss and postoperative hospital stay compared with OPN, even though the patients' backgrounds were not adjusted. Therefore, RAPN may be a viable option for managing T1 allograft tumors.

Genitourinary malignancies in kidney transplant recipients

Advances in immunosuppressive therapy and postoperative management have greatly improved the graft and patient survival rates after kidney transplantation; however, the incidence of post-transplant malignant tumors is increasing. Post-renal transplantation malignant tumors are associated with renal failure, immunosuppression, and viral infections. Moreover, the risk of developing cancer is higher in kidney transplant recipients than in the general population, and the tendency to develop cancer is affected by the background and environment of each patient. Recently, cancer after kidney transplantation has become the leading cause of death in Japan. Owing to the aggressive nature and poor prognosis of genitourinary malignancies, it is crucial to understand their epidemiology, risk factors, and best practices in kidney transplant recipients. This review has a special emphasis on the epidemiology, risk factors, and treatment protocols of genitourinary malignancies in kidney transplant recipients to enhance our understanding of the appropriate management strategies. Optimal immunosuppressive therapy and cancer management for these patients remain controversial, but adherence to the general guidelines is recommended.

Synchronous bilateral papillary renal cell carcinoma in the native kidneys after 10 Years of renal transplantation: Report of a case and review of the literature

A case of synchronous bilateral native kidneys papillary RCC is presented in a 48 year old patient who underwent a living donor kidney transplant 10 years prior. He was on regular immunosuppressant therapy. Despite the long term follow-up, bilateral cystic and exophytic masses were incidentally found on CT scan. Subsequent bilateral open radical nephrectomy revealed papillary RCC in both kidneys.

A Case of Acquired Cystic Kidney Disease From Chronic Renal Failure Without Dialysis

The kidneys play a vital role in maintaining homeostasis by filtering the blood of waste products and toxins, maintaining a delicate balance of fluids and electrolytes, and closely regulating blood pressure via the juxtaglomerular apparatus. Cystic kidney disease is a pathology of the kidneys that can be either acquired or congenital. This case report introduces a seventy-eight-year-old male with a medical history of a myocardial infarction and heart valve replacements who presented to the emergency department due to a recent fall at home unrelated to syncope. As he rose from his chair, the patient fell forward but was able to pick himself up from the ground. Upon further review, lab work revealed end-stage renal disease with a creatinine of 19.7 mg/dL (reference range: 0.6-1.2 mg/dL) and blood urea nitrogen of 186 mg/dL (reference range: 7-18 mg/dL). Potassium was 5.2 mmol/L (reference range: 3.5-5.1 mmol/L) and the electrocardiogram showed normal sinus rhythm. Urinalysis showed proteinuria of 100 mg/dL with high white blood cells 28/High-power field and red blood cells (RBCs) 3/HPF but no bacteria. Trace blood and leukocyte esterase were also noted. Microscopic analysis was significant only for epithelial cells 1/HPF. The patient also had symptomatic anemia with a hemoglobin of 6.4 g/dL, which contributed to his symptoms on presentation. Computed tomography of the abdomen and pelvis without intravenous or per oral contrast revealed numerous bilateral renal parenchymal cysts. After receiving two units of packed RBCs for severe anemia, he underwent several dialysis treatments during his stay. The patient denied a family history of polycystic kidney disease, though he had a deceased sister with unspecified "kidney problems." Acquired cystic kidney disease (ACKD) before dialysis is a rare phenomenon that prompts a careful history, physical exam, and diagnostic evaluation to avoid misdiagnosis and improper treatment. Although rare and not cited often in the literature, ACKD should be entertained in the differential diagnosis of this presentation.

Acquired Cystic Disease-Associated Renal Cell Carcinoma: A Systematic Review and Meta-analysis

Acquired cystic disease-associated renal cell carcinoma (ACD-RCC) is a common subtype of renal cell carcinoma (RCC) in end-stage renal disease (ESRD) patients. The current systematic review and meta-analysis was performed to evaluate the clinicopathological, and genetic characteristics of patients with ACD-RCC. A systematic search on three electronic databases including the Pubmed, Scopus, and Web of Science databases were performed until December 31, 2022. A meta-analysis was performed following the PRISMA 2020 Guidelines. Of 888 identified articles, full-text screening in 69 articles, there were 26 articles analyzed, with a total of 2314 tumors in 2199 patients, including 418 ACD-RCC tumors in 363 patients, 1340 clear cell RCC (ccRCC) tumors, 308 papillary RCC (pRCC) tumors. Most ACD-RCC patients were male (80.2%). All the ACD-RCC patients underwent prior dialysis with 148.2 months of mean dialysis duration. There were 8.7%, 3.4%, and 5.8% tumors at the T3-4 stage, N1 stage, and M1 stage, respectively. The mean overall survival of ACD-RCC patients was 39.6 months (95% CI, 26.6-52.5). Compared to ccRCC and pRCC, ACD-RCC patients had a longer duration of dialysis (MD: 103.5 and 31.77 months, respectively; 95% CI: [75.48; 131.53] and [0.95; 62.58], respectively), and a higher rate of multifocal tumors (MD: 3.46 and 2.45 tumors, respectively; 95% CI [1.71; 6.98] and [1.26; 4.79], respectively). Regarding genetic characteristics, chromosomes 3 and 16 were the 2 most frequent chromosomal aberrations. The missense mutation in KMT2C (25%) and TSC2 (18.75%) were the 2 most common gene mutations in ACD-RCC. In conclusion, the ACD-RCC subtype exhibited several distinct clinicopathological and genetic characteristics compared to others RCC subtypes. Further researchs are needed to assess the survival outcome and the genetic characteristics of this subtype.

How to manage renal masses in kidney transplant recipients? A collaborative review by the EAU-YAU kidney transplantation and renal cancer working groups

INTRODUCTION

Kidney transplant (KT) recipients have a four-times higher risk of renal malignancies compared to general population. As these patients frequently harbor bilateral or multifocal tumors, the management of renal masses is still under debate.

OBJECTIVE

To explore the current management of the native kidney masses in KT patients.

ACQUISITION OF EVIDENCE

We performed a literature search on MEDLINE/PubMed database. A number of 34 studies were included in the present review.

SYNTHESIS OF EVIDENCE

In frail patients with renal masses below 3 cm, active surveillance is a feasible alternative. Nephron-sparing surgery is not justified for masses in the native kidney. Radical nephrectomy is the standard treatment for post-transplant renal tumors of the native kidneys in KT recipients, with laparoscopic techniques leading to significantly less perioperative complication rates as compared to the open approach. Concurrent bilateral native nephrectomy at the time of transplantation can be considered in patients with renal mass and polycystic kidney disease, especially if no residual urinary output is present. Patients with localized disease and successful radical nephrectomy do not require immunosuppression adjustment. In metastatic cases, mTOR agents can ensure efficient antitumoral response, while maintaining proper immunosuppression in order to protect the graft.

CONCLUSIONS

Post-transplant renal cancer of the native kidneys is a frequent occurrence. Radical nephrectomy is most frequently performed for localized renal masses. A standardized and widely-approved screening strategy for malignancies of native renal units is yet to be implemented.

Wall Tension and Tubular Resistance in Kidney Cystic Conditions

The progressive formation of single or multiple cysts accompanies several renal diseases. Specifically, (i) genetic forms, such as adult dominant polycystic kidney disease (ADPKD), and (ii) acquired cystic kidney disease (ACKD) are probably the most frequent forms of cystic diseases. Adult dominant polycystic kidney disease (ADPKD) is a genetic disorder characterized by multiple kidney cysts and systemic alterations. The genes responsible for the condition are known, and a large amount of literature focuses on the molecular description of the mechanism. The present manuscript shows that a multiscale approach that considers supramolecular physical phenomena captures the characteristics of both ADPKD and acquired cystic kidney disease (ACKD) from the pathogenetic and therapeutical point of view, potentially suggesting future treatments. We first review the hypothesis of cystogenesis in ADPKD and then focus on ACKD, showing that they share essential pathogenetic features, which can be explained by a localized obstruction of a tubule and/or an alteration of the tubular wall tension. The consequent tubular aneurysms (cysts) follow Laplace's law. Reviewing the public databases, we show that ADPKD genes are widely expressed in various organs, and these proteins interact with the extracellular matrix, thus potentially modifying wall tension. At the kidney and liver level, the authors suggest that altered cell polarity/secretion/proliferation produce tubular regions of high resistance to the urine/bile flow. The increased intratubular pressure upstream increases the difference between the inside (Pi) and the outside (Pe) of the tubules (∆P) and is counterbalanced by lower wall tension by a factor depending on the radius. The latter is a function of tubule length. In adult dominant polycystic kidney disease (ADPKD), a minimal reduction in the wall tension may lead to a dilatation in the tubular segments along the nephron over the years. The initial increase in the tubule radius would then facilitate the progressive expansion of the cysts. In this regard, tubular cell proliferation may be, at least partially, a consequence of the progressive cysts' expansion. This theory is discussed in view of other diseases with reduced wall tension and with cysts and the therapeutic effects of vaptans, somatostatin, SGLT2 inhibitors, and potentially other therapeutic targets.

Multi-Scale Investigation of Human Renal Tissue in Three Dimensions

Histopathology as a diagnostic mainstay for tissue evaluation is strictly a 2D technology. Combining and supplementing this technology with 3D imaging has been proposed as one future avenue towards refining comprehensive tissue analysis. To this end, we have developed a laboratory-based X-ray method allowing for the investigation of tissue samples in three dimensions with isotropic volume information. To assess the potential of our method for micro-morphology evaluation, we selected several kidney regions from three patients with cystic kidney disease, obstructive nephropathy and diabetic glomerulopathy. Tissue specimens were processed using our in-house-developed X-ray eosin stain and investigated with a commercial microCT and our in-house-built NanoCT. The microCT system provided overview scans with voxel sizes of [Formula: see text] and the NanoCT was employed for higher resolutions including voxel sizes from [Formula: see text] to 210 nm. We present a methodology allowing for a precise micro-morphologic investigation in three dimensions which is compatible with conventional histology. Advantages of our methodology are its versatility with respect to multi-scale investigations, being laboratory-based, allowing for non-destructive imaging and providing isotropic volume information. We believe, that after future developmental work this method might contribute to advanced multi-modal tissue diagnostics.

Cystic Kidney Diseases That Require a Differential Diagnosis from Autosomal Dominant Polycystic Kidney Disease (ADPKD)

Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary cystic kidney disease, with patients often having a positive family history that is characterized by a similar phenotype. However, in atypical cases, particularly those in which family history is unclear, a differential diagnosis between ADPKD and other cystic kidney diseases is important. When diagnosing ADPKD, cystic kidney diseases that can easily be excluded using clinical information include: multiple simple renal cysts, acquired cystic kidney disease (ACKD), multilocular renal cyst/multilocular cystic nephroma/polycystic nephroma, multicystic kidney/multicystic dysplastic kidney (MCDK), and unilateral renal cystic disease (URCD). However, there are other cystic kidney diseases that usually require genetic testing, or another means of supplementing clinical information to enable a differential diagnosis of ADPKD. These include autosomal recessive polycystic kidney disease (ARPKD), autosomal dominant tubulointerstitial kidney disease (ADTKD), nephronophthisis (NPH), oral-facial-digital (OFD) syndrome type 1, and neoplastic cystic kidney disease, such as tuberous sclerosis (TSC) and Von Hippel-Lindau (VHL) syndrome. To help physicians evaluate cystic kidney diseases, this article provides a review of cystic kidney diseases for which a differential diagnosis is required for ADPKD.

Incidence, management and treatment outcomes of renal malignancy in a post-transplant recipient at a tertiary care centre: A 16-year experience

Introduction and Objective:

Although the incidence of malignancy in renal transplant recipients is on the rise owing to boom in the post-transplant immunosuppressive therapy, there is paucity of literature regarding their reporting and management. In this study, we report the incidence of de novo renal malignancies, post-renal transplantation at our centre over a 16-year period and discuss their management.

Methods:

All patients who underwent renal transplantation at our department between March 2004 and February 2020 were included and retrospectively reviewed. We analysed the incidence of renal malignancy both in the native kidney and the graft, histological subtype, time to and type of treatment.

Results:

A total of 376 patients underwent renal transplantation. Mean age of recipients was 48.2 and 52.15 years among those who developed cancer. 13 (2.93%) of 376 recipients developed urogenital malignancy, of whom 8 had renal cell carcinoma (RCC) in their native kidneys and 1 in the allograft. Transitional cell carcinoma (TCC) of renal pelvis was noted in three patients with one concomitant TCC of bladder. No treatment-related graft losses occurred in the native kidney malignancy. Patients with RCC underwent nephrectomy while TCC of renal pelvis underwent nephroureterectomy with bladder cuff excision. Transurethral resection was done for bladder tumour. All patients were followed up as per standard protocol.

Conclusion:

A rise in urological post-transplant malignancies mandates regular surveillance after renal transplantation to ensure early detection of de novo malignancies and early initiation of treatment. Goal should be to minimise adverse graft outcomes with no compromise on oncological outcomes.

Level of evidence:

Not applicable

Transplant Onconephrology in Patients With Kidney Transplants

Cancer is a leading cause of death in patients with kidney transplantation. Patients with kidney transplants are 10- to 200-times more likely to develop cancers after transplant than the general population, depending on the cancer type. Recent advances in cancer therapies have dramatically improved survival outcomes; however, patients with kidney transplants face unique challenges of immunosuppression management, cancer screening, and recurrence of cancer after transplant. Patients with a history of cancer tend to be excluded from transplant candidacy or are required to have long cancer-free wait time before wait-listing. The strategy of pretransplant wait time management may need to be revisited as cancer therapies improve, which is most applicable to patients with a history of multiple myeloma. In this review, we discuss several important topics in transplant onconephrology: the current recommendations for pretransplant wait times for transplant candidates with cancer histories, cancer screening post-transplant, post-transplant lymphoproliferative disorder, strategies for transplant patients with a history of multiple myeloma, and novel therapies for patients with post-transplant malignancies. With emerging novel cancer treatments, it is critical to have multidisciplinary discussions involving patients, caregivers, transplant nephrologists, and oncologists to achieve patient-oriented goals.

CT features of acquired cystic kidney disease-associated renal cell carcinoma

PURPOSE

Acquired cystic kidney disease-associated renal cell carcinoma (ACKD-RCC) is a relatively recently described entity with scarce literature describing its imaging appearance (1, 2). The purpose of this study was to determine typical and potentially unique features of ACKD-RCC on CT scan that could aid lesion identification.

MATERIALS AND METHODS

A retrospective review of the CT scans of 24 patients with 29 histologically proven ACKD-RCC lesions was performed. Imaging features were recorded based on consensus readings of two radiologists.

RESULTS

Tumors ranged in size from 1.2 to 5 cm. Nineteen lesions were right-sided and 10 left-sided. Nineteen lesions were exophytic. One patient had bilateral lesions and three patients had multiple lesions in the same kidney. All lesions had well-defined margins with 21 round, 7 lobulated and 1 crescentic in shape. On non-enhanced exam 4 lesions were hypodense, 16 iso-dense and 9 hyperdense; 5 had gross calcifications. Twenty two patients had contrast-enhanced CT exams, with 13 lesions demonstrating homogeneous enhancement (solid pattern) and 14 having inhomogeneous enhancement (cystic or mixed solid and cystic pattern). Only 1 patient had metastatic disease. Eight patients had a history of renal transplants.

CONCLUSION

ACKD-RCCs are well-defined lesions of variable size that are almost always rounded and most often exophytic. They occasionally have calcifications and are not uncommonly hyperdense on non-enhanced exam. They are most often iso-dense on non-enhanced exam and can be solid, cystic or mixed in attenuation on enhanced exam.

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%.

Urological Cancers and Kidney Transplantation: a Literature Review

PURPOSE OF REVIEW

The aim of this review is to provide an overview of epidemiology, risk factors, and treatment of urological malignancies in renal transplant recipients (RTR).

RECENT FINDINGS

Although optimal immunosuppressive therapy and cancer management in these patients remain controversial, adherence to general guidelines is recommended. Kidney transplantation is recognized as the standard of care for the treatment of end-stage renal disease (ESRD) as it offers prolonged survival and better quality of life. In the last decades, survival of RTRs has increased as a result of improved immunosuppressive therapy; nonetheless, the risk of developing cancer is higher among RTRs compared to the general population. Urological malignancies are the second most common after hematological cancer and often have more aggressive behavior and poor prognosis.

Incidental occurrence of papillary renal cell carcinoma in the native kidney with autosomal dominant polycystic kidney disease after renal transplantation: A case report

Autosomal dominant polycystic kidney disease (ADPKD) is one of the best-known genetic diseases. Almost half of the patients with ADPKD will develop end-stage renal disease, and the majority of patients are treated with renal transplantation. The current study presents a case that developed papillary renal cell carcinoma (PRCC) in the native right kidney 10 years after renal transplantation. PRCC is a not common malignant tumour entity (18.5% of all cases of renal cell carcinoma) compared with common clear cell renal carcinoma (65-70% of all cases of RCC).

Renal Cell Cancer and Chronic Kidney Disease

The association between chronic kidney disease (CKD) and renal cell carcinoma (RCC) is bidirectional and multifactorial. Risk factors such as hypertension, diabetes mellitus, obesity, and smoking increase the risk of both CKD and RCC. CKD can lead to RCC via an underlying cystic disease or oxidative stress. RCC can cause CKD because of the tumor itself, surgical reduction of renal mass (either partial or radical nephrectomy), and perioperative acute kidney injury. Medical therapies such as immune checkpoint inhibitors and vascular endothelial growth factor inhibitors can lead to acute kidney injury and resultant CKD. Clinicians need to be aware of the complex, bidirectional interplay between both diseases.

Malignancies after pediatric solid organ transplantation

As life expectancy among pediatric solid organ transplant recipients (SOTRs) improves, the risk of comorbid conditions such as malignancy post-transplantation has also increased. SOTRs are at elevated risks of post-transplantation lymphoproliferative disorders (PTLDs), and skin and solid cancers. PTLDs typically occur early following transplantation, while skin and solid cancers frequently arise in young adulthood (25-40 years). By 30 years following transplantation, 26-41% of pediatric SOTRs have developed cancer. Different risk factors exist for PTLD, and skin and solid cancers, which are modified by cumulative immunosuppression, infections, transplanted organ, and the underlying disease process associated with initial organ failure (e.g., kidney failure). Optimal cancer treatment strategies depend on the specific cancer type, stage, and patient comorbidities. Immunosuppression reduction may be beneficial for certain cancers but must be considered against the risks of acute and chronic rejection and allograft loss. Lifestyle counseling regarding smoking avoidance and sun protection, as well as human papillomavirus vaccination, is an important aspect of cancer prevention. Currently, no cancer screening guidelines exist specifically for pediatric SOTRs. Adult population screening guidelines have not been validated in transplant populations. Therefore, an individualized approach should be taken to cancer screening for pediatric SOTRs, accounting for other cancer risk factors.

Sex differences in cancer risk and outcomes after kidney transplantation

Kidney transplant recipients (KTRs) experience a two- to four-fold increased risk of developing and dying from cancer compared with the general population. High cancer risk results from the interaction of both modifiable and non-modifiable factors. This mapping review explores the impact of sex disparity on cancer's increased incidence and mortality after kidney transplantation (KT). In terms of age, population-based studies indicate that younger recipients of both sexes experience a higher risk of cancer, but this is more pronounced in young women. On the contrary, older men are more likely to be diagnosed with cancer, although their increased risk is not statistically significant compared with the general population. Regarding cancer type, studies show an increased risk of Kaposi sarcoma, gynecologic and lung cancer in women, and bladder and kidney cancer in men. Immune-related cancers such as pos-transplant lymphoproliferative disorders and melanoma are increased in both sexes. Mortality also shows differences between sexes. Although cancer is the second cause of death in both male and female KTRs, studies show higher overall mortality in men and elderly recipients. However, the relative risk of cancer mortality compared with the general population is higher at a younger age, with disparate results regarding sex. Female KTRs appear to die at a younger age than males when compared with the general population. Differences in cancer rates by sex after renal transplantation need further studies. A better understanding of sex-specific differences in cancer epidemiology after KT could help nephrologists to better address pre-transplant counseling, to establish early surveillance programs, and to plan modifiable risk factors such as immunosuppression.

Increased risk for renal cell carcinoma in end stage renal disease - a population-based case-control study

PURPOSE

End-stage renal disease (ESRD) is a known risk factor for the development of renal cell carcinoma (RCC). This case-control study was performed to assess the risk in a nationwide cohort and evaluate tumor characteristics and survival in the ESRD-RCC population.

METHODS

In this study, 9,299 patients with RCC identified in the National Swedish Kidney Cancer Register from 2005 until 2014 and 93,895 matched controls were linked to the Swedish Renal Registry and the National Patient Register. ESRD was defined as chronic kidney disease stage 5, kidney transplantation or kidney dialysis 0-40 years before the diagnosis of RCC.

RESULTS

A total of 117 patients with ESRD and subsequent RCC were identified and compared with 9,087 patients with RCC. There was a 4.5-times increased risk for RCC among ESRD patients (95% CI = 3.6-5.6; p < 0.001) compared to matched controls. Longer time with ESRD increased the risk of RCC (ESRD > 9 years, OR = 10.2, 95% CI = 7.0-14.8). The ESRD-RCC patients were younger (p = 0.002), had smaller tumors (p < 0.001) and had lower tumor stage (p = 0.045). The incidence of papillary and chromophobe RCC was higher and clear cell RCC lower among the ESRD patients (p < 0.001). The 5-year overall survival was 50% in ESRD-RCC patients and 63% in RCC-only patients (p < 0.05).

CONCLUSION

More than 9 years with ESRD increased the risk of developing RCC 10-times compared to individuals without ESRD and the tumors showed a different histopathological pattern. Despite a less advanced tumor stage at diagnosis, the overall survival in ESRD-RCC patients was lower compared to patients with RCC-only.

Post-transplant malignancies in pediatric organ transplant recipients

The majority of cancer diagnoses in pediatric solid organ transplant recipients (SOTRs) are post-transplantation lymphoproliferative disorders (PTLD) or skin cancers. However, pediatric SOTRs are also at significantly elevated risk for multiple other solid and hematological cancers. The risks of specific cancers vary by transplanted organ, underlying disease, and immunosuppression factors. More than one-quarter of pediatric SOTRs develop cancer within 30 years of transplantation and their risk of solid cancer is 14 times greater than the general population. Pediatric SOTRs are at significantly higher risk of cancer-associated death. Improving patient survival among pediatric SOTRs puts them at risk of adult epithelial cancers associated with environmental carcinogenic exposures. Vaccination against oncogenic viruses and avoidance of excessive immunosuppression may reduce the risk of solid cancers following transplantation. Patient and family education regarding photoprotection is an essential component of skin cancer prevention. There is significant variability in cancer screening recommendations for SOTRs and general population approaches are typically not validated for transplant populations. An individualized approach to cancer screening should be developed based on estimated cancer risk, patient life expectancy, and screening test performance.

Tubulocystic Renal Cell Carcinoma of the Native Kidney in a Renal Transplant Recipient: A Rare Case Report

Tubulocystic renal cell carcinoma (TCC) is a rare and newly recognized variant of renal cell carcinoma, which may mimic benign cystic disease of the kidney. To our knowledge, we present the first reported case of a patient who, despite standard preoperative workup, developed TCC of his native kidney soon after receiving kidney transplantation. He was appropriately treated with native nephrectomy and has had no signs of reoccurrence 7 years postoperatively. Given the significant risk of malignancy in renal transplant patients, this case emphasizes the need for close monitoring of native cystic disease before and after transplantation, with low threshold to proceed with surgical intervention.

Pathologic characterization of renal epithelial neoplasms arising in nonfunctioning kidneys

Nonfunctioning kidneys secondary to various etiologies display different histopathological features. Studies focused on incidence and types of renal neoplasms using the new World Health Organization and International Society of Urological Pathology classification system in various types of nonfunctioning kidneys are very limited. We identified 311 nephrectomies of nonfunctioning kidneys and categorized them into 5 categories: acquired cystic kidney disease (ACKD, n = 61); end-stage renal disease, nonspecific (ESRD, n = 63); adult polycystic kidney disease (APKD, n = 49); failed transplant kidney (FTK, n = 96); and those caused by obstructive conditions in the kidney (OCK, n = 42). ACKD (70%) and ESRD (43%) had higher cancer incidences than the other 3 groups (APKD = 2%, FTK = 0%, and OCK = 5%). Besides clear cell renal cell carcinoma (RCC) and papillary RCC, clear cell papillary RCC had a much higher incidence within ACKD patients (13/61) compared to other groups. ACKD-associated RCC was only identified in ACKD patients. ACKD patients had significantly longer dialysis duration compared to ESRD, APKD, and FTK. Although they had similar risk for clear cell RCC and papillary RCC, ACKD patients had a much higher risk for ACKD-associated RCC and clear cell papillary RCC than ESRD patients. Although most RCCs arising in these nonfunctioning kidneys were early pT1 stage, 6 ACKD patients and 3 ESRD patients had higher-stage diseases, which can be fatal if not treated appropriately. Therefore, precise clinicopathological classification of these nonfunctioning kidneys is important for predicting kidney cancer risk. These results indicate the need for active monitoring of the patients with high-risk nonfunctioning kidney diseases and appropriate surgical treatment when necessary.

Cancer in kidney transplant recipients

Cancer is the second most common cause of mortality and morbidity in kidney transplant recipients after cardiovascular disease. Kidney transplant recipients have at least a twofold higher risk of developing or dying from cancer than the general population. The increased risk of de novo and recurrent cancer in transplant recipients is multifactorial and attributed to oncogenic viruses, immunosuppression and altered T cell immunity. Transplant candidates and potential donors should be screened for cancer as part of the assessment process. For potential recipients with a prior history of cancer, waiting periods of 2-5 years after remission - largely depending on the cancer type and stage of initial cancer diagnosis - are recommended. Post-transplantation cancer screening needs to be tailored to the individual patient, considering the cancer risk of the individual, comorbidities, overall prognosis and the screening preferences of the patient. In kidney transplant recipients diagnosed with cancer, treatment includes conventional approaches, such as radiotherapy and chemotherapy, together with consideration of altering immunosuppression. As the benefits of transplantation compared with dialysis in potential transplant candidates with a history of cancer have not been assessed, current clinical practice relies on evidence from observational studies and registry analyses.

Renal cell carcinoma suspected at time of organ donation 2008-2016: A report of the OPTN ad hoc Disease Transmission Advisory Committee Registry

All 179 reports to the OPTN of potential renal cell carcinoma (RCC) transmission from 1/1/2008 through 12/31/2016 were reviewed. Cases were divided into those with donor tumor known or suspected at time of transplant (N = 147 donors), and those in which tumor was initially found after transplant (N = 32). We sought to understand the risk of transplanting either the affected kidney, the contralateral kidney or non-renal organs from donors with a suspected/confirmed unilateral RCC. In the case of RCC found prior to transplant, transplantation of 21 kidneys following excision of tumor, 47 contralateral kidneys and 198 non-renal organs was performed. No cases of RCC transmission were documented in this population. An additional six cases of live donor kidney transplantation involving resection of RCC were reported, also without transmission. Six of 9 other recipients in whom the diagnosis of RCC became available after implantation underwent allograft nephrectomy and 3 received tumor resection. No recurrent RCC was documented. Given the low rate of transmission and available treatment options, consideration should be given to judicious use of organs from donors with small solitary RCC.

Iatrogenic Disease of the Genitourinary Tract

Iatrogenic disease is defined as illness caused by diagnostic procedures or treatment given by health care professionals. More recently described treatment complications involving the genitourinary tract include newly recognized variants of renal carcinoma in the setting of dialysis/end-stage renal disease, treatment effect in genitourinary carcinomas, and medical renal disease caused by drug therapies, including immunotherapy. The objective of this review is to cover iatrogenic inflammatory diseases, pseudotumors and tumors of the kidney, bladder, prostate, testis and paratestis of most interest to surgical pathologists. For this reason, disease caused by the following will not be covered: iatrogenic glomerulonephritis, self-inflicted injury including the introduction of foreign bodies, surgical error, drugs of abuse and herbal medications, and iatrogenic disease in the transplant setting including ischemia/reperfusion injury. Emphasis is placed upon commonly encountered diseases in order to ensure that the review is of utility to practicing pathologists. The clinical context, pathophysiology and histopathology of each disease entity are covered.

Incidence and Mortality of Renal Cell Carcinoma after Kidney Transplantation: A Meta-Analysis

BACKGROUND

The incidence and mortality of renal cell carcinoma (RCC) after kidney transplantation (KTx) remain unclear. This study's aims were (1) to investigate the pooled incidence/incidence trends, and (2) to assess the mortality/mortality trends in KTx patients with RCC.

METHODS

A literature search was conducted using the MEDLINE, EMBASE and Cochrane databases from inception through October 2018. Studies that reported the incidence or mortality of RCC among kidney transplant recipients were included. The pooled incidence and 95% CI were calculated using a random-effect model. The protocol for this meta-analysis is registered with PROSPERO; no. CRD42018108994.

RESULTS

A total of 22 observational studies with a total of 320,190 KTx patients were enrolled. Overall, the pooled estimated incidence of RCC after KTx was 0.7% (95% CI: 0.5-0.8%, I2 = 93%). While the pooled estimated incidence of de novo RCC in the native kidney was 0.7% (95% CI: 0.6-0.9%, I2 = 88%), the pooled estimated incidence of RCC in the allograft kidney was 0.2% (95% CI: 0.1-0.4%, I2 = 64%). The pooled estimated mortality rate in KTx recipients with RCC was 15.0% (95% CI: 7.4-28.1%, I2 = 80%) at a mean follow-up time of 42 months after RCC diagnosis. While meta-regression analysis showed a significant negative correlation between year of study and incidence of de novo RCC post-KTx (slopes = -0.05, P = 0.01), there were no significant correlations between the year of study and mortality of patients with RCC (P = 0.50). Egger's regression asymmetry test was performed and showed no publication bias in all analyses.

CONCLUSIONS

The overall estimated incidence of RCC after KTX was 0.7%. Although there has been a potential decrease in the incidence of RCC post-KTx, mortality in KTx patients with RCC has not decreased over time.

Fluroine-18 fluorodeoxyglucose-positron emission tomography/computer tomography in staging of renal cell carcinoma arising from a native kidney with liver and bone metastasis in a renal transplant patient

Renal cell carcinoma (RCC) of the native kidney accounts for <5% of all malignancies found in transplant recipients. There have been only a few reported cases comprising of few renal transplant patients with RCC of native kidneys due to the relative rarity of the condition. Fluorine-18 Fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) is used in the staging of RCC. Prognosis of metastatic RCC is poor. We report the first case of 55-year-old postrenal transplant recipient diagnosed with RCC of the native kidney with liver and bone metastases imaged using F-18 FDG PET/CT.

Etiology of increased cancer incidence after solid organ transplantation

Over the past decades, there has been an encouraging increase in survival after solid organ transplantation. However, with longer life spans, more transplant recipients are at risk of dying with functioning grafts from illnesses such as cancer and cardiovascular conditions. Malignancy has emerged as an important cause of death in transplant recipients and is expected to become the leading cause of death in transplanted patients within the next decade. While it is known that solid organ transplant recipients have a three to five-fold increased risk of developing cancer compared with the general population, the mechanisms that lead to the observed excess risk in transplant recipients are less clear. This review explores the etiology of the increased cancer incidence in solid organ transplant including the effect of immunosuppressants on immunosurveillance and activation of oncogenic viruses, and carcinogenic effects of these medications; the role of chronic stimulation of the immune system on the development of cancer; and the impact of pre-existing cancer risk factors and factors related to end-stage organ disease on the cancer excess incidence in solid organ transplant recipients.

Risk factors associated with post-kidney transplant malignancies: an article from the Cancer-Kidney International Network

In kidney transplant recipients, cancer is one of the leading causes of death with a functioning graft beyond the first year of kidney transplantation, and malignancies account for 8-10% of all deaths in the USA (2.6 deaths/1000 patient-years) and exceed 30% of deaths in Australia (5/1000 patient-years) in kidney transplant recipients. Patient-, transplant- and medication-related factors contribute to the increased cancer risk following kidney transplantation. While it is well established that the overall immunosuppressive dose is associated with an increased risk for cancer following transplantation, the contributive effect of different immunosuppressive agents is not well established. In this review we will discuss the different risk factors for malignancies after kidney transplantation.

Renal Cell Carcinoma in Renal Transplantation: The Case for Surveillance

INTRODUCTION

Between January 2013 and September 2015, 135 consecutive renal transplant patients were screened prospectively with ultrasound for renal cell carcinoma (RCC).

RESULTS

Eighteen ultrasound abnormalities were identified with 4 solid lesions detected. Fifty-six other patients were screened retrospectively by referring nephrology groups, with 6 additional malignancies found.

CONCLUSION

As a result of our data, we recommend and have instituted annual ultrasound screening of native kidneys in all renal transplant patients.

Case Report: Spontaneous Hemorrhage of a Rare Renal Tumor in the Native Kidney of a Renal Transplant Recipient

Renal cancers are some of the most common solid organ malignancies found during follow-up of patients who have undergone renal transplantation (RT). In this case report, we describe a life-threatening spontaneous hemorrhage of a rare subtype of renal cell carcinoma in the native kidney of a 27-year-old man, 4 years after RT. After fluid resuscitation and stabilization, the patient underwent emergent open radical nephrectomy with the final histopathology reporting T1bN0Mx mucinous tubular and spindle cell (MTSC) carcinoma. This case report highlights the need to consider an underlying malignancy in patients who presents with spontaneous hemorrhage of native kidneys after RT.

Acquired cystic kidney disease: an under-recognized condition in children with end-stage renal disease

Acquired cystic kidney disease (ACKD) is a condition that occurs predominantly in patients with end-stage renal disease (ESRD). In contrast to hereditary cystic kidney disease, ACKD is characterized by the presence of multiple small cysts in bilaterally small kidneys. Limited pediatric data suggest a high incidence (21.6-45.8%) of ACKD in children on dialysis, comparable to that in adults, with an increased frequency associated with a longer duration of dialysis. Recent research has shed light on the pathogenesis of ACKD, such as activation of proto-oncogenes. Although most patients with ACKD are asymptomatic, the condition can be complicated by renal cell carcinoma. Routine surveillance should therefore be considered in at-risk populations.

Urologic malignancies in kidney transplantation

With advances in immunosuppression, graft and patient outcomes after kidney transplantation have improved considerably. As a result, long-term complications of transplantation, such as urologic malignancies, have become increasingly important. Kidney transplant recipients, for example, have a 7-fold risk of renal cell carcinoma (RCC) and 3-fold risk of urothelial carcinoma (UC) compared with the general population. While extrapolation of data from the general population suggest that routine cancer screening in transplant recipients would allow for earlier diagnosis and management of these potentially lethal malignancies, currently there is no consensus for posttransplantation RCC or UC screening as supporting data are limited. Further understanding of risk factors, presentation, optimal management of, and screening for urologic malignancies in kidney transplant patients is warranted, and as such, this review will focus on the incidence, surveillance, and treatment of urologic malignancies in kidney transplant recipients.

Daunting but Worthy Goal: Reducing the De Novo Cancer Incidence After Transplantation

Solid-organ transplant recipients are at increased risk of developing de novo malignancies compared with the general population, and malignancies become a major limitation in achieving optimal outcomes. The prevention and the management of posttransplant malignancies must be considered as a main goal in our transplant programs. For these patients, immunosuppression plays a major role in oncogenesis by both impairement of immunosurveillance, enhancement of chronic viral infection, and by direct prooncogenic effects. It is essential to manage the recipient with a long-term adapted screening program beginning before transplantation to use a prophylaxis to decrease infection-related cancer, to propose a viral monitoring, and to modulate the immunosuppression toward lower doses especially for calcineurin inhibitors. Indeed, strategies to induce tolerance or to allow a dramatic reduction of the immunosuppression burden are the more promising approaches for the reduction of the posttransplant malignancies.

A national study of kidney graft tumor treatments: Toward ablative therapy

BACKGROUND

Results of the conservative treatment of renal cell carcinomas arising in functional renal transplants are unknown compared to transplant nephrectomy. Only small series or case reports have been reported.

METHODS

Data were collected from 32 transplantation centers nationwide on cases of de novo tumors in functional renal transplants presumed to be malignant between January 1988 and December 2013.

RESULTS

Among 116 de novo transplant tumors, 62 were treated conservatively including: 48 by partial nephrectomy (PN) and 14 by thermal ablation (TA). These patients were compared to 30 other patients who were treated by transplant nephrectomy. The median age of the transplanted kidneys at the time of diagnosis was 43.5 years old as calculated from the donor's age. Tumors treated by transplant nephrectomy presented more often with symptoms (pain, fever, impaired condition, hematuria) than tumors treated conservatively (P = .019). After PN, final histology showed 27 (47.5%) papillary carcinomas, 19 (32.2%) clear cell carcinomas, 1 mixed carcinoma, and 2 oncocytomas. The median tumor size treated by PN was 24 mm with no difference in comparison to the TA group. Nine patients treated by PN had postoperative complications (21%), including 4 requiring operative intervention (Clavien IIIb). None of the patients treated by TA had complications. Specific survival was 100% at the time of last follow-up (median time after treatment 37 months) for patients treated by PN or TA.

CONCLUSION

PN proved to be efficient in the treatment of small tumors of transplanted kidneys with good long-term functional and oncologic outcomes, including avoiding return to dialysis. TA seems to be an alternative therapy with good results in selected patients.

Renal cell carcinoma: links and risks

This review provides an overview of the incidence of renal cell carcinoma (RCC) and a summary of the most commonly associated risk factors. A literature review was performed with a focus on recent studies with a high level of evidence (large prospective cohort studies and meta-analyses). The incidence rate of RCC varies globally, with the rate rising rapidly in more developed regions, demonstrating the effects of increased use of diagnostic imaging and prevalence of modifiable risk factors. Based on the current evidence, cigarette smoking, obesity, and hypertension are the most well-established risk factors for sporadic RCC worldwide. Acquired cystic kidney disease is also a significant risk factor, specifically in dialysis patients. There is increasing evidence for an inverse association between RCC risk and moderate alcohol consumption. Certain analgesics and occupational exposure have been linked to an increased risk of RCC, although data are limited. Diets rich in fruits and vegetables may provide a protective effect.

Management of Indeterminate Cystic Kidney Lesions: Review of Contrast-enhanced Ultrasound as a Diagnostic Tool

Indeterminate cystic kidney lesions found incidentally are an increasingly prevalent diagnostic challenge. Standard workup includes Bosniak classification with contrast-enhanced computed tomography (CT) or magnetic resonance imaging (MRI). However, these tests are costly and not without risks. Contrast-enhanced ultrasound (CEUS) is a relatively new technique with lower risk of adverse events than iodine-containing contrast or gadolinium. In our review of the evidence for characterization of cystic kidney lesions with CEUS, CEUS displayed sensitivity (89%-100%) and negative predictive value (86%-100%) comparable to contrast-enhanced CT or MRI, with no decrease in specificity compared with CT and only a slight decrease compared with MRI.

Risk of cancer in retransplants compared to primary kidney transplants in the United States

Recipients of kidney transplantation have elevated risk of developing cancer. There are limited data on cancer risk in recipients of kidney retransplantation. We used data from the Transplant Cancer Match Study, which links the U.S. transplant registry with 15 cancer registries. Cancer incidence in recipients of kidney retransplantation and primary kidney transplants was compared utilizing Poisson regression, adjusting for demographic and medical characteristics. We assessed 109 224 primary recipients and 6621 retransplants. Compared to primary recipients, retransplants were younger (median age 40 vs. 46 yr), had higher PRA, and more often received induction with polyclonal antibodies (43% vs. 25%). A total of 5757 cancers were observed in primary recipients and 245 in retransplants. Overall cancer risk was similar in retransplants compared with primary recipients (incidence rate ratio [IRR] 1.06, 95% CI 0.93-1.20, adjusted for age, gender, race/ethnicity, PRA, and use of polyclonal induction). However, renal cell carcinoma (RCC) occurred in excess among retransplants (adjusted IRR 2.03, 95% CI 1.45-2.77), based on 514 cases in primary recipients and 43 cases in retransplants. Overall cancer risk did not differ in retransplants compared to primary recipients. Increased risk of RCC may be explained by the presence of acquired cystic kidney disease, which is more likely to develop with additional time with kidney disease and time spent on dialysis waiting for retransplantation.

Renal cancer in kidney transplanted patients

Renal cancer occurs more frequently in renal transplanted patients than in the general population, affecting native kidneys in 90% of cases and the graft in 10 %. In addition to general risk factors, malignancy susceptibility may be influenced by immunosuppressive therapy, the use of calcineurin inhibitors (CNI) as compared with mammalian target of rapamycin inhibitors, and the length of dialysis treatment. Acquired cystic kidney disease may increase the risk for renal cancer after transplantation, while autosomal dominant polycystic kidney disease does not seem to predispose to cancer development. Annual ultrasound evaluation seems appropriate in patients with congenital or acquired cystic disease or even a single cyst in native kidneys, and every 2 years in patients older than 60 years if they were on dialysis for more than 5 years before transplantation. Immunosuppression should be lowered in patients who develop renal cancer, by reduction or withdrawal of CNI. Although more evidence is still needed, it seems reasonable to shift patients from CNI to everolimus or sirolimus if not already treated with one of these drugs, with due caution in subjects with chronic allograft nephropathy.

Efficacy and safety of sorafenib for treatment of Japanese metastatic renal cell carcinoma patients undergoing hemodialysis

BACKGROUND

Little information has been published on the use of tyrosine kinase inhibitors for treatment of patients undergoing hemodialysis (HD). We investigated the efficacy and safety of sorafenib for metastatic renal cell carcinoma (mRCC) patients undergoing HD.

METHODS

Twenty patients undergoing HD were treated with sorafenib as first-line therapy for mRCC at our hospital between April 2008 and August 2014. Patient medical records were retrospectively reviewed to evaluate the response to sorafenib and treatment-related toxicity.

RESULTS

Fifteen and 5 patients were classified in the intermediate and poor risk groups, respectively, of the Memorial Sloan-Kettering Cancer Center risk model. Eighteen patients had 3 or more metastatic lesions, and 7 patients had metastases in 2 or more organs. Of 16 patients who had previously undergone nephrectomy, 8 were pathologically diagnosed with non-clear-cell carcinoma. The median duration of sorafenib therapy was 4.7 months. Sorafenib was discontinued owing to progressing disease for 15 patients and because of serious adverse events (AE) (≥grade 3) for 4 patients, i.e. subarachnoid hemorrhage, cerebral hemorrhage, sepsis, and syncope for 1 patient each. Median time to progression was 6.3 months, and median overall survival was 14.2 months.

CONCLUSIONS

In this study, many patients had unfavorable clinical features, for example poor risk classification and metastases in multiple organs. Although sorafenib treatment of HD patients seems feasible, careful monitoring is needed because of the tendency for a high incidence of serious AE, even when a reduced dose is administered.