Solid-type RCC originating from native kidneys in renal transplant recipients should be monitored cautiously

Small renal masses in kidney transplantation: overview of clinical impact and management in donors and recipients

Kidney transplantation is the best replacement treatment for the end-stage renal disease. Currently, the imbalance between the number of patients on a transplant list and the number of organs available constitutes the crucial limitation of this approach. To expand the pool of organs amenable for transplantation, kidneys coming from older patients have been employed; however, the combination of these organs in conjunction with the chronic use of immunosuppressive therapy increases the risk of incidence of graft small renal tumors. This narrative review aims to provide the state of the art on the clinical impact and management of incidentally diagnosed small renal tumors in either donors or recipients. According to the most updated evidence, the use of grafts with a small renal mass, after bench table tumor excision, may be considered a safe option for high-risk patients in hemodialysis. On the other hand, an early small renal mass finding on periodic ultrasound-evaluation in the graft should allow to perform a conservative treatment in order to preserve renal function. Finally, in case of a renal tumor in native kidney, a radical nephrectomy is usually recommended.

Simultaneous Living Donor Kidney Transplant and Laparoscopic Native Nephrectomy: An Approach to Kidney Transplant Candidates with Suspected Renal-Cell Carcinoma

Introduction: Kidney transplant candidates are occasionally found during the pre-transplant evaluation to have a suspicious mass in a native kidney. Further work-up and management of such a mass may delay transplantation for several months, which may create logistic barriers to transplant, particularly if there are timing constraints of the donor. In this study, we report our experience with simultaneous living donor kidney transplant and laparoscopic native nephrectomy, where the indication for nephrectomy was a suspicious lesion. Methods: We performed a retrospective review of patients who underwent simultaneous kidney transplant and native nephrectomy using prospectively collected data. We analyzed relevant patient characteristics, surgical details, pathologic results, and long-term follow-up. Results: We identified 16 patients who underwent simultaneous living donor kidney transplantation and laparoscopic native nephrectomy at our institution between 2013 and 2018. Ten (62.5%) patients were found to have renal-cell carcinoma (RCC) on the final pathology. No patients had recurrent RCC, at a median follow-up of 4 years. Conclusion: For patients who are planning to undergo a living donor kidney transplant and are found to have a small mass that is suspicious for RCC, a simultaneous living donor kidney transplant and laparoscopic native nephrectomy is a possible approach in selected patients.

Characteristics and Graft Survival of Kidney Transplant Recipients with Renal Cell Carcinoma

BACKGROUND

The incidence of renal cell carcinoma (RCC) is higher in kidney transplant recipients (KTRs) compared to the general population. However, the risk factors and outcomes based on the diagnosis of RCC after kidney transplantation are limited.

METHODS

We analyzed risk factors for the development of RCC in KTRs transplanted at our institution between 1994 and 2016. We compared the incidence of graft failure and mortality in KTRs with RCC to matched controls using 5:1 event density sampling. Identifying the risk factors of RCC and patient and graft survival were outcomes of interest.

RESULTS

There were 4,178 KTRs performed at our institution during the study period, and 51 patients were diagnosed with RCC. Recipients were followed until graft failure or death. We did not identify commonly looked at baseline characteristics associated with the risk of RCC. Comparing KTRs with RCC to matched controls, RCC patients were younger (47.5 vs. 49.6 years, p < 0.01), received basiliximab induction more commonly (p = 0.01), had hypertension and glomerulonephritis as causes of end-stage renal disease (p = 0.01), and were more likely to be smokers (p < 0.01). RCC was significantly associated with death-censored graft failure (adjusted hazard ratio [HR]: 1.76; 95% CI: 1.02-3.03; p = 0.04) but not patient death (adjusted HR: 0.95; 95% CI: 0.50-1.83; p = 0.89).

CONCLUSION

In our experience, RCC had a detrimental impact on graft survival among KTRs, highlighting the potential benefit of early diagnosis and optimal immunosuppression management in optimizing graft survival.

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.

The Risk of Tumour Recurrence in Patients Undergoing Renal Transplantation for End-stage Renal Disease after Previous Treatment for a Urological Cancer: A Systematic Review

CONTEXT

Renal transplantation is the gold standard renal replacement therapy in end-stage renal disease owing to its superior survival and quality of life compared with dialysis. When the potential recipient has a history of cancer, the waiting period before renal transplantation is usually based on the Cincinnati Registry.

OBJECTIVE

To systematically review all available evidence on the risk of cancer recurrence in end-stage renal disease patients with a history of urological cancer.

EVIDENCE ACQUISITION

Medline, Embase, and the Cochrane Library were searched up to March 2017 for all relevant publications reporting oncologic outcomes of urological cancer in patients who subsequently received a transplantation or remained on dialysis. The primary outcome was time to tumour recurrence. Secondary outcomes included cancer-specific and overall survival. Data were narratively synthesised in light of methodological and clinical heterogeneity. The risk of bias of each included study was assessed.

EVIDENCE SYNTHESIS

Thirty-two retrospective studies enrolling 2519 patients (1733 dialysed, 786 renal transplantation) were included. For renal cell carcinomas, the risks of recurrence, cancer-specific, and overall survival were similar between transplantation and dialysis. For prostate cancer, most of the tumours had favourable prognoses consistent with nomograms. Studies dealing with urothelial carcinomas (UCs) mainly included upper urinary tract UC in the context of aristolochic acid nephropathy, for which the risks of synchronous bilateral tumour and recurrence were high. Data on testicular cancer were scarce.

CONCLUSIONS

Immunosuppression after renal transplantation does not affect the outcomes and natural history of low-risk renal cell carcinomas and prostate cancer. Therefore, the waiting time from successful treatment for these cancers to transplantation could be reduced. Except in the particular situation of aristolochic acid nephropathy, more studies are needed to standardise the waiting period after UC owing to the paucity of data.

PATIENT SUMMARY

Renal transplantation does not appear to increase the risk of recurrence of renal carcinoma or the recurrence of low-risk prostate cancer compared with dialysis. More reliable evidence is required to recommend a standard waiting period especially for urothelial and testicular carcinomas.