Genitourinary malignancies in solid organ transplant recipients

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.

De Novo Urological Malignancies After Renal Transplantation: An Asian 30-Year Experience

BACKGROUND

As the incidence of urological malignancies after renal transplantation (RT) is observed to be greater than in the general population, a better understanding of them is important. We present our experience with urological tumors in RT recipients at our transplant center, and analyze their incidence, management and outcomes.

MATERIALS AND METHODS

A retrospective analysis of 2177 RT recipients on follow-up at our center between 1990 and 2022 was conducted for de novo genitourinary malignancy. Patients diagnosed with malignancy before transplantation were excluded. Clinicopathological data at diagnosis and follow-up were collected and analyzed. Kaplan-Meier estimates were used to evaluate overall survival (OS) and cancer-specific survival (CSS). Statistical analysis was performed using IBM SPSS v.24 (IBM Corp., Armonk, NY, USA).

RESULTS

The overall incidence of Urological malignancies was 3.9%, with 89 cancers diagnosed in 85 patients. Renal cell carcinoma was most common (n = 61, 68.5%), followed by prostate cancer (n = 10, 11.2%), urothelial carcinoma (n = 10, 11.2%), squamous cell carcinoma of the penis/scrotum (n = 7, 7.9%), and testicular cancer (n = 1, 1.1%). Mean duration between transplantation and diagnosis of malignancy was 9.9 (0.4-20.7) years. At a median follow-up of 4.6 (018.2) years, 27 deaths were seen; 7(25.9%) were due to urological malignancy. CSS rates were 86% and 78% at five and ten years, respectively, after diagnosis.

CONCLUSION

We present one of the largest series of de novo urological malignancies observed over an extended 30-year follow-up of RT recipients, demonstrating an elevated risk in line with other studies. Regular surveillance for malignancies is advised, in order to ensure early diagnosis and management.

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.

Management of Urological Malignancy in Heart and Lung Transplant Recipients: An Irish National Cohort Study

OBJECTIVES

Following the first hearttransplantin Ireland in 1985, there have been almost 700 deceased donor heart and lung transplants carried out in Ireland at a single institution. In this retrospective study, our aim was to assess the incidence and management of urological malignancies arising in this national cohort.

MATERIALS AND METHODS

Our retrospective analysis included all heart and lung transplant recipients identified as having a urological malignancy. Primary outcome variables included incidence, management, and clinical outcomes following cancer diagnosis.

RESULTS

A total of 28 patients (4.1%) had radiologically or histologically confirmed urological malignancies. Fourteen patientswere diagnosedwith prostate cancer, with 13 who underwent radical treatment. Eight renal cell carcinomas were diagnosed in heart transplant recipients, with 5 who underwent nephrectomies. Two bladder cancers and 1 uppertract urothelial carcinoma were diagnosed and managed with endoscopic resection, radiotherapy, and nephroureterectomy, respectively. Two patients were diagnosed with penile squamous cell carcinoma and managed with radical surgery and lymph node dissection/sampling, with 1 patient receiving adjuvant chemoradiotherapy.

CONCLUSIONS

Urological malignancies are not common in heart and lung transplant recipients; however, standard management options can be safely used, including radical surgery. Prospective monitoring of these patients and potential considerations for screening should be maintained.

Detection and Characterization of Atypical Renal Cysts and Solid Renal Masses in Kidney Transplant Patients by Use of Dual-Energy CT Iodine Maps

OBJECTIVE. The purpose of this study was to evaluate whether dual-energy CT follow-up of kidney transplant recipients performed with only two contrast-enhanced phases and reconstructed material maps has the same diagnostic efficiency as triphasic conventional CT in detection and characterization of atypical renal cysts and renal masses. MATERIALS AND METHODS. In a retrospective study, 175 renal transplant patients underwent dual-energy CT as part of their follow-up (monoenergetic unenhanced, late contrast-enhanced, and tubular contrast-enhanced dual-energy phases). An unenhanced virtual series and material separation maps were reconstructed. ROIs were marked on theses lesions, the bladder, and the psoas muscle. Material suppressed iodine was used to record attenuation measurements on the unenhanced and virtual unenhanced series in the tubular and late phases, and material concentration measurements were obtained on the iodine density images. The delivered doses for each series were registered. RESULTS. One hundred one renal lesions (spontaneous attenuation > 20 HU, size > 10 mm) were detected. An iodine concentration threshold greater than 1500 μg/mL was associated with excellent diagnostic performance (sensitivity, 100%; specificity, 92.55%; positive predictive value, 50%; negative predictive value, 100%) for detection of suspect lesions (enhancement > 20 HU). The two lesions with an iodine concentration greater than 5000 μg/mL corresponded to the only two histologically proven cancers. CONCLUSION. Iodine concentration maps obtained with dual-energy CT perform as well as enhanced images obtained at conventional CT in the detection and characterization of tissue and atypical cystic renal lesions in kidney transplant recipients. Use of this method could reduce radiation dose, especially by avoiding the unenhanced series.

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.

Incidence and treatment of malignant tumors of the genitourinary tract in renal transplant recipients

Purpose:

To provide data of the incidence and management of common urological malignancies in renal transplant recipients.

Materials and Methods:

We conducted a retrospective analysis of a prospective database from August 1967 to August 2015. A descriptive analysis of the sample was performed.

Results:

Among 1256 consecutive RTR a total of 88 patients developed malignancies (7%). There were 18 genitourinary tumors in the 16 patients (20.45 % of all malignant neoplasms), incidence of 1.27%. The most common neoplasm encounter was renal cancer (38.8%), followed by urothelial carcinoma (33.3%). Median follow-up of transplantation was 197 months (R, 36-336). Mean time from RT to cancer diagnosis 89±70 months (R, 12-276). CsA and AZA was the most common immunosuppression regimen in 68.75%. Mean follow-up after diagnosis was 103±72 months (R 10-215). Recurrence free survival rate of 100%. Overall survival of 89.5% of the sample; there were two non-related cancer deaths during follow-up.

Conclusions:

The incidence of neoplasms in RTR was lower than in other series, with favorable functional and oncologic results after treatment. This suggests that actions to reduce the risk of these malignancies as well as a strict follow-up are mandatory for an early detection and treatment.

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.

Treatment options and predictive factors for recurrence and cancer-specific mortality in bladder cancer after renal transplantation: A multi-institutional analysis

OBJECTIVES

Bladder cancer (BC) in the transplanted population can represent a challenge owing to the immunosuppressed state of patients and the higher rate of comorbidities. The objective was to analyze the treatment of BC after renal transplant (RT), focusing on the mode of presentation, diagnosis, treatment options and predictive factors for recurrence.

MATERIAL AND METHODS

We conducted an observational prospective study with a retrospective analysis of 88 patients with BC after RT at 10 European centers. Clinical and oncologic data were collected, and indications and results of adjuvant treatment reviewed. The Kaplan-Meier method and uni- and multivariate Cox regression analyses were performed.

RESULTS

A total of 10,000 RTs were performed. Diagnosis of BC occurred at a median of 73 months after RT. Median follow-up was 126 months. Seventy-one patients (81.6%) had non-muscle invasive bladder cancer, of whom 29 (40.8%) received adjuvant treatment; of these, six (20.6%) received bacillus Calmette-Guérin and 20 (68.9%) mitomycin C. At univariate analysis, patients who received bacillus Calmette-Guérin had a significantly lower recurrence rate (P=.043). At multivariate analysis, a switch from immunosuppression to mTOR inhibitors significantly reduced the risk of recurrence (HR 0.24, 95% CI: 0.053-0.997, P=.049) while presence of multiple tumors increased it (HR 6.31, 95% CI: 1.78-22.3, P=.004). Globally, 26 patients (29.88%) underwent cystectomy. No major complications were recorded. Overall mortality (OM) was 32.2% (28 patients); the cancer-specific mortality was 13.8%.

CONCLUSIONS

Adjuvant bacillus Calmette-Guérin significantly reduces the risk of recurrence, as does switch to mTOR inhibitors. Multiple tumors increase the risk.

Incidental Eosinophilic Chromophobe Renal Cell Carcinoma in Renal Allograft

The incidence of renal cell carcinoma (RCC) in renal allograft in transplant recipients is 0.22-0.25%. De novo clear cell, papillary, and chromophobe RCCs and RCCs with sarcomatoid differentiation originating in renal allograft have been reported. Routine surveillance for graft tumours is not routinely practiced and these tumours are commonly asymptomatic and incidentally discovered. We describe a case of incidental, eosinophilic chromophobe RCC in a 31-year-old, long-term renal transplant male recipient, who presented with acute gastroenteritis 11 years after transplantation. The graft was nonfunctional at the time of presentation. Abdominal ultrasound and computed tomography scan demonstrated 1.8 cm well-defined, round enhancing lesion, confined to the renal allograft and suspicious for malignancy. Pathological examination of graft nephrectomy specimen showed gross, histopathological, and immunohistochemical features of eosinophilic chromophobe RCC. Fifty-five months after surgery, the patient was alive and free of malignancy. To the best of our knowledge, only five chromophobe RCCs originating in a renal allograft were previously described in English literature. We suggest that chromophobe RCC should be considered in the differential diagnosis of renal allograft mass, including eosinophilic tumours, and emphasise the importance of periodic screening of renal allograft in all renal transplant recipients.

Polyomavirus Replication and Smoking Are Independent Risk Factors for Bladder Cancer After Renal Transplantation

BACKGROUND

Solid organ transplant recipients are at increased risk for developing malignancies. Polyomaviruses (PV) have been historically associated with experimental tumor development and recently described in association with renourinary malignancies in transplant patients. The aim of this study was to investigate the relationship between PV replication and smoking, and the development of malignant neoplasms in kidney transplant recipients.

METHODS

A retrospective case-control study was conducted for PV replication in all kidney biopsies and urine cytologies performed between 1998 and 2014 from kidney transplant recipients at the University of Maryland Medical Center. Polyomavirus-positive patients (n = 943) were defined as having any of the following: a kidney biopsy with PV associated nephropathy, any urine cytology demonstrating "decoy" cells, and/or significant polyomavirus BK viremia. Polyomavirus-negative matched patients (n = 943) were defined as lacking any evidence of PV replication. The incidence of malignancy (excluding nonmelanoma skin tumors) was determined in these 1886 patients and correlated with demographic data and history of smoking.

RESULTS

There was a 7.9% incidence of malignant tumors after a mean posttransplant follow-up of 7.9 ± 5.4 years. Among all cancer subtypes, only bladder carcinoma was significantly associated with PV replication. By multivariate analysis, only PV replication and smoking independently increased the risk of bladder cancer, relative risk, 11.7 (P = 0.0013) and 5.6 (P = 0.0053), respectively.

CONCLUSIONS

The findings in the current study indicate that kidney transplant recipients with PV replication and smoking are at particular risk to develop bladder carcinomas and support the need for long-term cancer surveillance in these patients.

Cancer and mTOR Inhibitors in Transplant Recipients

Malignancy is the second most common single cause of death observed in organ transplant recipients. The excess cancer risk is related to intensity and duration of immunosuppressive therapy and inversely to recipient age. Immunodeficiency and (chronic/oncogenic) viral infections together constitute a major risk. Nonmelanoma skin cancer, Kaposi sarcoma, and posttransplant lymphoproliferative disease have standardized incidence ratios exceeding 10- or 50-fold. The mammalian target of rapamycin (mTOR) inhibitors, sirolimus and everolimus, are increasingly used after organ transplantation with potential advantages in virus-associated posttransplant malignancies as well as anti-cancer properties. Despite a seemingly clear mechanism of action and solid rationale for their use in cancer therapy, mTORis have met only modest success rates in clinical trials with advanced malignancies except for specific tumors, such as Kaposi sarcoma and mantle cell lymphoma. Because mTORis are primarily cytostatic, not cytotoxic, the observed clinical efficacy is a reflection of disease stabilization rather than tumor regression. Nonmelanoma skin cancers, in particular cutaneous squamous cell carcinoma, have the highest standardized incidence ratios in transplant recipients. Recent meta-analyses and randomized trials on secondary prevention of squamous cell carcinoma observed a reduction in cumulative tumor load, suggesting most benefit to be gained by early conversion to an mTOR inhibitor-based maintenance regime. There is ongoing debate on the mechanisms involved including withdrawal of the carcinogenic effects of calcineurin inhibitors and/or their impact on chronic (oncogenic) viral infections. At present, there is, however, insufficient evidence for the primary use of mTORis as protective agents against most other cancer types.

TCC in Transplant Ureter--When and When Not to Preserve the Transplant Kidney

We present four cases of transitional cell carcinoma of the transplant ureter (TCCtu). In three cases, localized tumor resection and a variety of reconstructive techniques were possible. Transplant nephrectomy with cystectomy was performed as a secondary treatment in one locally excised case. Transplant nephroureterectomy was performed as primary treatment in one case. The role of oncogenic viruses and genetic fingerprinting to determine the origin of TCCtu are described. Our cases and a systematic literature review illustrate the surgical, nephrological, and oncological challenges of this uncommon but important condition.

Iodine-125 prostate seed brachytherapy in renal transplant recipients: an analysis of oncological outcomes and toxicity profile

Purpose

Prostate cancer is among the most common non-cutaneous neoplasms affecting renal transplant recipients (RTRs). Available treatments including radical prostatectomy and external beam radiotherapy carry a risk of damage to the transplanted kidney, ureters, or bladder. We assessed the safety and efficacy of Iodine-125 (¹²⁵I) prostate seed brachytherapy as an alternative to surgery and radiotherapy in these individuals.

Material and methods

We retrospectively reviewed our brachytherapy database to identify patients with a prior history of renal transplantation, who had undergone seed implantation for localized prostate cancer. Long term PSA control and treatment related toxicity, including graft dysfunction, urinary, rectal, and sexual complications, were assessed and compared with published outcomes for surgery and external beam radiotherapy.

Results

Of 1054 patients treated with permanent seed implantation from 2002-2012, we identified four who had a prior history of renal transplantation. Mean time from renal transplantation to prostate cancer diagnosis was 13 years. Mean follow-up after seed implantation was 44 months (range 12-60 months). All four patients remain free of PSA progression. No peri-operative complications were experienced following seed implantation, and all four patients continued to have normal graft function. Long term urinary and rectal function scores were comparable to reported outcomes for seed brachytherapy in the non-transplant population.

Conclusions

¹²⁵I prostate seed brachytherapy is associated with high rates of biochemical control and minimal toxicity to the renal graft in RTRs. This treatment should be considered as an alternative to surgery in managing RTRs with localized prostate cancer.

Renal cell carcinoma in the native and allograft kidneys of renal transplant recipients

PURPOSE

Renal cell carcinoma develops in renal transplant recipients 30 or more times more commonly than in the general population. We assessed the prevalence, histology and outcome of renal cell carcinoma in a large, single center recipient population.

MATERIALS AND METHODS

We examined outcomes in patients who underwent renal transplantation at our center to determine the prevalence, histology and outcome of those in whom renal cell carcinoma developed.

RESULTS

A total of 3,568 patients received a renal allograft at our institution between 1966 and 2009. A total of 45 renal cell carcinomas were diagnosed in the native kidney of 39 patients (1.1%) and in 8 (0.2%) renal cell carcinoma developed in the allograft kidney. Mean age at diagnosis was 51.6 and 48.2 years in patients with native kidney and allograft tumors, respectively. The mean interval between transplantation and the native or allograft renal cell carcinoma diagnosis was 10.6 and 12.1 years, respectively. Clear cell renal cell carcinoma was the most common tumor histology in native kidneys, diagnosed in 21 cases, while papillary renal cell carcinoma was diagnosed in 20. Five allograft tumors were papillary renal cell carcinoma and 3 were clear cell renal cell carcinoma. Native kidney tumors were managed by radical nephrectomy in 44 or by observation after biopsy. Allograft tumors were managed by transplant nephrectomy in 3 cases, radio frequency ablation in 3 and partial nephrectomy in 2. At a mean 6.6-year followup 32 patients with native kidney renal cell carcinoma were alive while 7 with allograft tumors were alive at a mean 3.6-year followup.

CONCLUSIONS

Renal cell carcinoma is more prevalent in patients with renal transplantation than the general population, although the subtype distribution differs. Excellent survival is seen at more than 6 years after treatment.

Management of Bladder Cancer following Solid Organ Transplantation

Objective. Present our experience managing bladder cancer following liver and renal transplantation. Methods. Single institution retrospective review of patients diagnosed with bladder urothelial carcinoma (BUC) following solid organ transplantation between January 1992 and December 2007. Results. Of the 2,925 renal and 2,761 liver transplant recipients reviewed, we identified eleven patients (0.2%) following transplant diagnosed with BUC. Two patients with low grade T1 TCC were managed by TURBT. Three patients with CIS and one patient with T1 low grade BUC were treated by TURBT and adjuvant BCG. All four are alive and free of recurrence at a mean follow-up of 51 ± 22 months. One patient with T1 high grade BUC underwent radical cystectomy and remains disease free with a follow-up of 98 months. Muscle invasive TCC was diagnosed in four patients at a median of 3.6 years following transplantation. Two patients are recurrence free at 24 and 36 months following radical cystectomy. Urinary diversion and palliative XRT were performed in one patient with un-resectable disease. Conclusions. Bladder cancer is uncommon following renal and liver transplantation, but it can be managed successfully with local and/or extirpative therapy. The use of intravesical BCG is possible in select immunosuppressed patients.

Urological involvement in renal transplantation

Historically, urologists were the primary surgeons in renal transplantation. Specialization and increased complexity of the field of transplantation, coupled with a de-emphasis of vascular surgical training in urology, has created a situation where many renal transplants are carried out by surgeons with a general surgery background. Because of its genitourinary nature, however, urological input in renal transplantation is still vital. For living donors, a urologist should be involved to help evaluate and prepare certain patients for eventual donation. This could involve both medical and surgical intervention. Additionally, urologists who carry out living donor nephrectomy maintain a sense of ownership in the renal transplant process and provide a unique opportunity to the trainees of that particular program. For renal transplant recipients, preoperative evaluation of voiding dysfunction and other genitourinary anomalies might be necessary before the transplant. Also, occasional surgical intervention to prepare a patient for renal transplant might be necessary, such as in a patient with a small renal mass that is detected by a screening pretransplant ultrasound. Intraoperatively, for patients with complex urological reconstructions that might be related to the etiology of the renal failure (urinary diversion, bladder augmentation), a urologist who is familiar with the anatomy should be available. Postoperatively, urological evaluation and intervention might be necessary for patients who had a pre-existing urological condition or who might have developed something de novo after the transplant. Although renal transplant programs could consult an on-call urologist for particular issues on an as-needed basis, having a urologist, who has repeated exposure to the particular issues and procedures that are involved with renal transplantation, and who is part of a dedicated multidisciplinary renal transplant team, provides optimal quality of care to these complex patients.

Development of urological cancers in renal transplant recipients: 30-year experience at the Frankfurt Transplant Center

Fatal post-transplant malignancies with a high proportion of genitourinary neoplasms represent a serious long-term challenge. With continuous improvement of the allograft and patient survival, cancer development after renal transplantation may soon turn to the leading morbidity cause. In a retrospective single-center study of 1990 renal transplant recipients between November 1979 and November 2009, records of patients with urological neoplasms including epidemiological, clinical and survival parameters were accessed. Sixty-six de novo urological malignancies in 58 recipients were recorded in the study period, being most common after skin cancers (15.6% of enregistered tumors). From these, 29 were renal cell cancers, including five neoplasms of transplanted kidney, 24 transitional cell carcinomas, 11 prostate carcinomas, and two germ cell carcinomas with incidence rates of 1.5%, 1.2%, 0.9% and 0.2%, respectively. The patient follow up was virtually complete. Tumor-related death was found in 44% of cases. By multivariate analysis, no influence of either duration of dialysis, mode or duration of immunosuppression, gender or age at transplantation on overall patient survival could be demonstrated. This study, documenting a 30-year single center experience, emphasizes the increased risk for urological neoplasms occuring after renal transplantation. Screening strategies for urological cancers should be optimized.

Urological issues in pediatric renal transplantation

PURPOSE OF REVIEW

The pediatric patient with end-stage renal disease provides a great opportunity for the involvement of the pediatric urologist because of the high incidence of associated urologic anomalies.

RECENT FINDINGS

Renal transplant remains the procedure of choice in the child with end-stage renal disease. The durability of survival of the graft is impacted by successful management of the genitourinary tract.

SUMMARY

Preoperative, intraoperative, and postoperative evaluation is critical for the child with associated urologic disease and end-stage renal disease. Early and appropriate management may stabilize renal function and prolong the time to transplant. Due to the relatively long life expectancy of children compared with adults with end-stage renal disease, appropriate management may be of benefit to avoid the morbidity associated with renal replacement therapy. In certain children, the appropriate management and reconstruction of the genitourinary tract may allow for a planned and preemptive renal transplant, thus avoiding dialysis.

Prostate cancer in renal transplant recipients

BACKGROUND

We conducted a retrospective multi-centre study to determine the characteristics of prostate cancer in renal transplant recipients (RTR) and to analyse the relation with immunosuppressive maintenance therapies.

METHODS

Patients from 19 French transplant centres diagnosed with prostate cancer at least 1 year after kidney transplantation were included in this study. Data regarding demographics, kidney transplantation, prostate cancer and immunosuppressive treatment were analysed.

RESULTS

Sixty-two patients met the eligibility criteria for this study. Thirty-eight patients (61.3%) received calcineurin inhibitors (CNI) and azathioprine (AZA) with or without steroids, twenty received CNI with or without steroids (32.2%) and four received CNI and mycophenolate mofetil (6.5%). Patients with CNI and AZA immunosuppressive therapy presented more high-stage cancer (T3 and T4) when compared to patients receiving CNI alone (47.5% versus 15%, respectively, P = 0.03). A non-significant increase in lymph node invasion was found in patients receiving CNI and AZA compared to patients receiving CNI alone (21% versus 5%, P = 0.16). In the multivariate analysis, the immunosuppressive regimen with CNI and AZA was the only independent risk factor for locally advanced disease (P = 0.007).

CONCLUSION

Our results showed that RTR are at risk for early occurrence and for locally advanced prostate cancer, especially when they received a CNI and AZA maintenance immunosuppressive therapy.

Management of solid tumours in organ-transplant recipients

Malignancy is a well-recognised complication of transplantation and can occur de novo, as a recurrence of a pre-existing malignancy, or from transmission of malignancy from the donor. Common de-novo malignancies are those of the skin and the lymphoreticular system. Various solid-organ cancers have also been reported in transplant recipients and each poses a unique management challenge in view of the unusual setting. We review solid-organ cancers in transplant recipients and their management, including surveillance and prevention.

Renal Cell Carcinoma in Renal Transplant Patients

OBJECTIVES

To report our experience with renal cell carcinoma in patients with end-stage renal failure receiving dialysis at two institutions that perform a large number of transplantations. Renal cell carcinoma is more frequent in patients with end-stage renal failure treated with dialysis and in renal transplant patients than in the population at large.

METHODS

We reviewed the case histories of 1375 consecutive patients who had transplanted kidneys functioning for more than 1 year.

RESULTS

Eleven renal tumors were found in 10 patients (1.37%); 10 of the tumors (90%) were in the native kidney (9 unilateral and 1 bilateral) and 1 (10%) was in the transplanted kidney. The tumors in the native kidneys were discovered incidentally. Three were in organs removed for treatment of arterial hypertension and the other seven were found by ultrasonography. The tumor in the transplanted kidney was found after nephrectomy for the treatment of hematuria. The tumor types were clear cell in six, papillary in four, and chromophobe in one. Of the 9 patients who were treated with radical nephrectomy, 7 were alive with no evidence of the disease and 2 had died of other causes, also with no evidence of the disease. One patient who already had metastases at the diagnosis did not undergo surgery and died 4 months later.

CONCLUSIONS

The native kidneys of renal transplant patients should be examined by ultrasonography annually because they are at greater risk of renal cell carcinoma. Radical nephrectomy cures those cases in which the tumors are clinically localized and 6 cm or less in size.

Cell therapy and the safety of embryonic stem cell-derived grafts

Recent developments in the identification, in vitro culture and differentiation of stem cells point to the unprecedented potential of these cells, or their derivatives, to cure degenerative disorders. Human embryonic stem cells (hESC) offer the particular advantage of prolonged proliferative capacity and great versatility in the lineages that can be formed in culture. Translating these advantages into clinical benefits faces many challenges, including efficient differentiation into the desired cell type(s), maintaining genetic stability during long-term culture and, finally, ensuring the absence of potentially tumorigenic hESC from the final product. It is this final safety issue that will form the focus of this review.