Acquired Cystic Kidney Disease and Renal Cell Cancer after Transplantation: Time to Rethink Screening?

Screening for renal cell carcinoma in renal transplant recipients: a single-centre retrospective study

OBJECTIVES

The primary objective of our study was to evaluate the effectiveness of renal cell carcinoma (RCC) screening in renal transplant (RT) recipients.

DESIGN

Single-centre retrospective study.

SETTING AND PARTICIPANTS

1998 RT recipients who underwent RT at Memorial Hermann Hospital (MHH) Texas Medical Center (TMC) between 1 January 1999 and 31 December 2019 were included and we identified 16 patients (0.8%) with RCC. An additional four patients with RCC who underwent RT elsewhere but received follow-up at MHH TMC were also included. Subject races included white (20%), black (50%), Hispanic (20%) and Asian (10%).

OUTCOME MEASURES

The RCC stage at diagnosis and outcomes were compared between patients who were screening versus those who were not.

RESULTS

We identified a total of 20 patients with post-RT RCC, 75% of whom were men. The median age at diagnosis was 56 years. RCC histologies included clear cell (75%), papillary (20%) and chromophobe (5%). Patients with post-RT RCC who had screening (n=12) underwent ultrasound or CT annually or every 2 years, whereas eight patients had no screening. All 12 patients who had screening had early-stage disease at diagnosis (stage I (n=11) or stage II (n=1)) and were cured by nephrectomy (n=10) or cryotherapy (n=2). In patients who had no screening, three (37.5%) had stage IV RCC at diagnosis and all of whom died of metastatic disease. There was a statistically significant difference in RCC-specific survival in patients who were screened (p=0.01) compared with those who were not screened.

CONCLUSION

All RT recipients who had RCC diagnosed based on screening had early-stage disease and there were no RCC-related deaths. Screening is an effective intervention in RT recipients to reduce RCC-related mortality.

Steady-state ferumoxytol-enhanced MRI: early observations in benign abdominal organ masses and clinical implications

INTRODUCTION

The off-label use of ferumoxytol as a vascular MR imaging agent is growing rapidly. However, the properties of ferumoxytol suggest that it may play an important role in the detection and characterization of abdominal mass lesions.

METHODS

Thirty-six patients with benign abdominal mass lesions who underwent MR angiography with ferumoxytol also had T2-weighted HASTE imaging and fat-suppressed 3D T1-weighted imaging. The T1 and T2 enhancement characteristics of the lesions were analyzed and correlated with other imaging modalities and/or surgical findings and/or clinical follow-up.

RESULTS

In all patients with benign masses in the liver (n = 22 patients), spleen (n = 6 patients), kidneys (n = 33 patients), adrenal (n = 2 patients) and pancreas (n = 4 patients), based on the enhancement characteristics with ferumoxytol, readers were confident of the benign nature of the lesions and their conclusions were consistent with correlative imaging, tissue sampling and follow-up. One patient with a suspicious enhancing 2F Bosniak renal cyst had renal cell carcinoma confirmed on biopsy.

CONCLUSION

Ferumoxytol-enhanced MRI can increase diagnostic confidence for benign abdominal masses and can increase the conspicuity of mass lesions, relative to unenhanced MRI.

Changes in cancer incidence and outcomes among kidney transplant recipients in the United States over a thirty-year period

Recipients of kidney transplants have elevated cancer risk compared with the general population. Improvements over time in transplant care and cancer treatment may have affected incidence and outcomes of cancer among recipients of kidney transplant. To evaluate this, we used linked United States transplant and cancer registry data to study 101,014 adult recipients of kidney transplants over three decades (1987-1996, 1997-2006, 2007-2016). Poisson regression was used to assess trends in incidence for cancer overall and seven common cancers. Associations of cancer with risk of death-censored graft failure (DCGF) and death with functioning graft (DWFG) were evaluated with Cox regression. We also estimated absolute risks of DCGF and graft failure following cancer for recipients transplanted in 2007-2016. There was no significant change in the incidence of cancer overall or for six common cancers in recipients across the 1987-2016 period. Only the incidence of prostate cancer significantly decreased across this period after multivariate adjustment. Among recipients of kidney transplants with non-Hodgkin lymphoma, there were significant declines over time in elevated risks for DCGF and DWFG but no significant changes for other combined cancers. For recipients transplanted in the most recent period (2007-2016), risks following cancer diagnosis remained high, with 38% experiencing DWFG and 14% graft failure within four years of diagnosis. Absolute risk of DWFG was especially high following lung cancer (78%), non-Hodgkin lymphoma (38%), melanoma (35%), and colorectal cancer (49%). Thus, across a 30-year period in the United States, there was no overall change in cancer incidence among recipients of kidney transplants. Despite improvements for non-Hodgkin lymphoma, cancer remains a major cause of morbidity and mortality.

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.

Posttransplant Malignancy

Posttransplant malignancy is a leading cause of death after solid organ transplantation (SOT). Recipients of SOT are at significantly higher risk of multiple cancers compared with the general population, most notably nonmelanoma skin cancer and posttransplant lymphoproliferative disorders. Risk factors for posttransplant malignancy include history of malignancy, immunosuppression, oncogenic viral infections, sun exposure, and disease-specific associations. Early detection and treatment of malignancies can improve survival.

Imaging of haemodialysis: renal and extrarenal findings

Electrolyte alterations and extra-renal disorders are quite frequent in patients undergoing haemodialysis or peritoneal dialysis. The native kidneys may be the site of important pathologies in patients undergoing dialysis, especially in the form of acquired renal cystic disease with frequent malignant transformation. Renal neoplasms represents an important complication of haemodialysis-associated acquired cystic kidney disease and imaging surveillance is suggested. Extra-renal complications include renal osteodistrophy, brown tumours, and thoracic and cardiovascular complications. Other important fields in which imaging techniques may provide important informations are arteriovenous fistula and graft complications.

Teaching points

• Renal neoplasms represent a dreaded complication of haemodialysis.

• In renal osteodystrophy bone resorption typically manifests along the middle phalanges.

• Brown tumours are well-defined lytic lesions radiographically, possibly causing bone expansion.

• Vascular calcifications are very common in patients undergoing haemodialysis.

• Principal complications of the AV fistula consist of thrombosis, aneurysms and pseudoaneurysms.

Epidemiology of de novo malignancies after solid-organ transplantation: immunosuppression, infection and other risk factors

Organ transplantation is an increasingly used medical procedure for treating otherwise fatal end-stage organ diseases, and a large number of anti-rejection drugs have been developed to prolong long-term survival of both the individual and the transplanted organ. However, the prolonged use of immunosuppressive drugs is well known to increase the risk of opportunistic diseases, particularly infections and virus-related malignancies. Although transplant recipients experience a nearly twofold elevated risk for all types of de novo cancers, persistent infections with oncogenic viruses are associated with up to hundredfold increased risks. Women of the reproductive age are growing in number among the recipients of solid-organ transplants, but specific data on cancer outcomes are lacking. This article updates evidences linking iatrogenic immunosuppression, persistent infections with oncogenic viruses, other risk factors and post-transplant malignancies. Epidemiological aspects, tumourigenesis related to oncogenic viruses, clinical implications, as well as primary and secondary prevention issues are discussed to offer clinicians and researchers alike an update of an increasingly important topic.

Growth hormone, insulin-like growth factor-1, and the kidney: pathophysiological and clinical implications

Besides their growth-promoting properties, GH and IGF-1 regulate a broad spectrum of biological functions in several organs, including the kidney. This review focuses on the renal actions of GH and IGF-1, taking into account major advances in renal physiology and hormone biology made over the last 20 years, allowing us to move our understanding of GH/IGF-1 regulation of renal functions from a cellular to a molecular level. The main purpose of this review was to analyze how GH and IGF-1 regulate renal development, glomerular functions, and tubular handling of sodium, calcium, phosphate, and glucose. Whenever possible, the relative contributions, the nephronic topology, and the underlying molecular mechanisms of GH and IGF-1 actions were addressed. Beyond the physiological aspects of GH/IGF-1 action on the kidney, the review describes the impact of GH excess and deficiency on renal architecture and functions. It reports in particular new insights into the pathophysiological mechanism of body fluid retention and of changes in phospho-calcium metabolism in acromegaly as well as of the reciprocal changes in sodium, calcium, and phosphate homeostasis observed in GH deficiency. The second aim of this review was to analyze how the GH/IGF-1 axis contributes to major renal diseases such as diabetic nephropathy, renal failure, renal carcinoma, and polycystic renal disease. It summarizes the consequences of chronic renal failure and glucocorticoid therapy after renal transplantation on GH secretion and action and questions the interest of GH therapy in these conditions.

Incidence, predictors, costs, and outcome of renal cell carcinoma after kidney transplantation: USRDS experience

INTRODUCTION

We carried out an analysis of the United States Renal Data System to determine the incidence, risk factors, prognosis, and costs associated with the diagnosis of renal cell carcinoma (RCC) after kidney transplantation.

METHODS

This is a retrospective cohort of 40,821 Medicare primary renal transplant recipients transplanted from January 1, 2000, to July 1, 2005, and followed up till December 31, 2005, excluding those with prior RCC or nephrectomy. Kaplan-Meier analysis was performed to determine the time of occurrence of RCC, and Cox regression was used to determine factors associated with RCC.

RESULTS

Three hundred sixty-eight patients were diagnosed with RCC within 3 years after transplant (incidence of 3.16 per 1000 person years). The 3-year incidence of RCC posttransplant was 9.29 per 1000 person years (2.3%) for those with pretransplant cysts and 3.08 per 1000 person years (0.7%) without pretransplant cysts. RCC was diagnosed disproportionately early posttransplant in patients with cysts. Cysts were independently associated with increased risk of RCC, as was male gender, older recipient, donor age, African American recipient, increased time on dialysis and acute rejection within first year posttransplant. RCC was associated with increased risk of mortality with a higher risk with pretransplant cysts. Patients who developed RCC had higher cumulative median costs ($55,456 at 2 years) than those who did not develop RCC ($40,369). There was no "clustering" of RCC in individual states or centers more than would be expected by chance.

CONCLUSION

RCC was diagnosed disproportionately early in patients with pretransplant renal cysts and was associated with a worse prognosis and increased costs.

Renal cell carcinoma

Renal Cell Carcinoma (RCC) has the highest mortality rate of the genitourinary cancers and the incidence of RCC has risen steadily. If detected early, RCC is curable by surgery although a minority are at risk of recurrence. Increasing incidental detection and an ageing population has led to active surveillance as an option for patients with small renal masses. RCC is heterogeneous and comprises several histological cell types with different genetics, biology and behavior. The identification of the genes predisposing to inherited syndromes with RCC has provided much of our knowledge of the molecular basis of early sporadic RCC. Many of the oncogenes and tumor suppressor genes that are mutated leading to pathway dysregulation in RCC remain to be elucidated. Global studies of copy number, gene sequencing, gene expression, miRNA expression and gene methylation in primary RCC will lead towards this goal. The natural history of RCC indicated by candidate precursor lesions, multifocal or bilateral disease, growth rate of small renal masses under surveillance, and high risk populations provide insight into the behavior of this disease. The use of molecular markers for early detection and prognosis merits more attention with ongoing advances in omics technologies. This review focuses on early RCC, that is disease confined within the renal capsule.

Renal cystic diseases and renal neoplasms: a mini-review

The past two decades have witnessed recognition of several new types of renal cell carcinoma, each with distinct cytogenetic abnormalities. Included are several genetic and acquired cystic kidney diseases associated with development of renal cell carcinoma, the topic of this review. The risk in patients with autosomal dominant polycystic kidney disease is not accurately known but may be slightly increased. The risk for patients with von Hippel-Lindau disease is substantial, and death from renal cancer is common. For patients with tuberous sclerosis complex, the challenge is recognition of the occasional malignancy arising in a field of many benign tumors. Patients with end-stage kidney disease and acquired cystic kidney disease may develop a variety of renal cell carcinoma types. Progress in understanding the molecular basis of renal cyst formation and neoplastic disease has fostered development of targeted therapies that now hold promise for a group of neoplasms whose cure was traditionally dependent on surgical approaches.

Features and outcomes of renal cell carcinoma of native kidneys in renal transplant recipients

OBJECTIVE

To outline the features and outcomes of renal cell carcinoma (RCC) in native kidneys of renal transplant recipients, who are at increased risk of developing this disease.

PATIENTS AND METHODS

We retrospectively studied the clinicopathological features and survival of 28 surgically treated RCCs, which developed in 24 renal transplant recipients. Features and outcomes were compared with 671 patients with RCC who had no renal transplant.

RESULTS

The median interval between renal transplantation and the occurrence of RCC was 5.6 years. Acquired cystic kidney disease was present in 83% of the transplanted patients. Compared with the patients with RCC and no renal transplant, RCCs of native kidneys in transplant recipients were more frequently incidental findings (92% vs 77%, P = 0.092), multifocal (39% vs 15%, P < 0.001), bilateral (17% vs 4%, P = 0.006), had lower T stages (P = 0.040), were smaller (P = 0.027), of lower grades (P = 0.010), were more frequently papillary (43% vs 19%, P = 0.019) and occurred at a significantly younger age (P = 0.022). After a median follow-up of 6.7 years, eight renal transplant recipients had died (33%), but only two deaths were due to RCC. Survival with metastatic RCC was only 4 months, if a full resection of all metastatic sites was not achieved. In multivariate analysis the presence of a renal transplant had no effect on survival.

CONCLUSIONS

Most RCCs in renal transplant recipients are incidental low-stage, low-grade tumours with a favourable prognosis. The outstanding pathological findings are bilateral occurrence, papillary subtype and multifocality. Prognosis of metastatic RCC is poor but might be favourable if all metastases are resected. Screening for early detection of asymptomatic RCC is advocated.