Distinguishing characteristics of urothelial carcinoma in kidney transplant recipients between China and Western countries

De novo upper tract urothelial carcinoma after renal transplantation: a single-center experience in China

BACKGROUND

Long-term prognosis and risk factors of de novo upper tract urothelial carcinoma after renal transplantation were rarely studied. Thus, the aim of this study was to investigate the clinical features, risk factors, and long-term prognosis of de novo upper tract urothelial carcinoma after renal transplantation, especially the impact of aristolochic acid on tumor, using a large sample.

METHODS

106 patients were enrolled in retrospective study. The endpoints included overall survival, cancer-specific survival, bladder or contralateral upper tract recurrence-free survival. Patients were grouped according to aristolochic acid exposure. Survival analysis was performed using Kaplan-Meier curve. Log-rank test was used to compare the difference. Multivariable cox regression was conducted to evaluate the prognostic significance.

RESULTS

Median time from transplantation to development of upper tract urothelial carcinoma was 91.5 months. Cancer-specific survival rate at 1, 5, 10 years was 89.2%, 73.2%, 61.6%. Tumor staging (≥ T2), lymph node status (N +) were independent risk factors for cancer-specific death. Contralateral upper tract recurrence-free survival rate at 1, 3, 5 years was 80.4%, 68.5%, 50.9%. Aristolochic acid exposure was independent risk factor for contralateral upper tract recurrence. The patients exposed to aristolochic acid had more multifocal tumors and higher incidence of contralateral upper tract recurrence.

CONCLUSION

Both higher tumor staging and positive lymph node status were associated with a worse cancer-specific survival in patients with post-transplant de novo upper tract urothelial carcinoma, which highlighted the importance of early diagnosis. Aristolochic acid was associated with multifocality of tumors and higher incidence of contralateral upper tract recurrence. Thus, prophylactic contralateral resection was suggested for post-transplant upper tract urothelial carcinoma, especially for patients with aristolochic acid exposure.

Aristolochic acid-containing Chinese herbal medicine and upper urinary tract urothelial carcinoma in Taiwan: a narrative review

PURPOSE

The high incidence of upper urinary tract urothelial carcinoma (UTUC) in Taiwan is largely due to exposure to aristolochic acid (AA), a principal component of Aristolochia-based herbal medicines. Here we systematically review the molecular epidemiology, clinical presentation and biomarkers associated with AA-induced UTUC.

METHODS

This is a narrative review. Medline, Embase, and Web of Science were searched from inception to December 31, 2021. Studies evaluating the association, detection, and clinical characteristics of AA and UTUC were included.

RESULTS

A nationwide database revealed 39% of the Taiwanese population had been exposed to AA-containing herbs between 1997 and 2003. Epidemiological reports revealed AA posed a significantly higher hazard for renal failure and UTUC in herbalists and the general population who ingested AA-containing herbs. The presence of aristolactam-DNA adducts and a distinctive signature mutation, A:T to T:A transversions, located predominantly on the non-transcribed DNA strand, with a strong preference for deoxyadenosine in a consensus sequence (CAG), was observed in many UTUC patients. Clinically, AA-related UTUC patients were characterized by a younger age, female gender, impaired renal function and recurrence of contralateral UTUC. To date, there are no preventive measures, except prophylactic nephrectomy, for subjects at risk of AA nephropathy or AA-related UTUC.

CONCLUSION

AA exposure via Aristolochia-based herbal medicines is a problem throughout Taiwan, resulting in a high incidence of UTUC. Aristolactam-DNA adducts and a distinctive signature mutation, A:T to T:A transversions, can be used as biomarkers to identify AA-related UTUC. AA-related UTUC is associated with a high recurrence rate of contralateral UTUC.

Native Kidney Hydronephrosis Is Associated with Upper Urinary Tract Urothelial Carcinoma in Post-Kidney Transplantation Patients

BACKGROUND

Upper urinary tract urothelial carcinoma (UTUC) is the most common malignancy occurring after kidney transplantation (KT) in Taiwan. The aim of this study was to investigate the association between native kidney hydronephrosis and UTUC in post-KT patients.

METHODS

From 2003 to 2018, we conducted a retrospective cohort study that enrolled 1005 post-KT patients, 67 of whom were subsequently diagnosed with UTUC. We divided patients into two groups based on whether or not they had UTUC. Multivariate analysis and Kaplan-Meier plot were used to evaluate if native kidney hydronephrosis was associated with post-KT UTUC.

RESULTS

The total cohort consisted of 612 men (60.9%) and 393 women (39.1%) with a mean age of 48.2 ± 12.0 at KT. The mean follow-up time was 118.6 ± 70.2 months, and mean time from KT to UTUC was 7.53 years. There was a significant gender difference with a female predominance among the UTUC patients (73.1% versus 26.9%, p < 0.001). Native kidney hydronephrosis occurred more frequently in the UTUC group (68.7% versus 4.8%, p < 0.001). Multivariate analysis showed that native kidney hydronephrosis and female gender were significantly associated with UTUC with odds ratios of 35.32 (95% CI, 17.99-69.36; p < 0.001) and 3.37 (95% CI, 1.55-7.29; p = 0.002), respectively. UTUC in the post-KT patients also showed aggressive pathological characteristics and a tendency toward bilateral lesions (41.8%).

CONCLUSIONS

Native kidney hydronephrosis is significantly associated with post-KT UTUC patients in Taiwan. Native kidney hydronephrosis may be a deciding factor for standard nephroureterectomy and bladder cuff excision in selected patients. Nevertheless, almost half of the patients with kidney hydronephrosis do not present with UTUC at the end of our study.

Diagnosis and Management of a De Novo Urothelial Carcinoma in a Kidney Allograft: A Case Report

INTRODUCTION

Following renal transplantation, the incidence of malignancies is 3-5 times higher than that of healthy individuals. Among other type of cancers, the risk of urological tumors is also elevated. However, only a few cases of de novo transitional cell carcinomas occurring in renal allografts have been reported.

CASE REPORT

A 63-year-old tertiary transplanted male patient was urgently hospitalized for a painless macroscopic hematuria. Ultrasonography revealed pyelectasis and a hematoma in the renal pelvis. A percutaneous nephrostomy tube was inserted. An anterograde pyelography was performed later, where a filling defect was still observable in the location of the previously reported hypoechoic mass. Contrast-enhanced ultrasonography showed enhancement of the lesion. An ultrasound-guided percutaneous biopsy was performed. The histologic evaluation revealed a high-grade transitional cell carcinoma. A whole-body staging computed tomography scan did not show signs of metastatic disease. The renal allograft was surgically removed. No disease progression was observed during the 21-month follow-up period.

CONCLUSIONS

Painless hematuria and asymptomatic hydronephrosis occurring after kidney transplantation should raise the possibility of urothelial carcinoma in the kidney graft. Contrast-enhanced ultrasound should be considered as a first-line diagnostic modality because it is easily accessible and does not raise concerns about nephrotoxicity or radiation burden.

Upper urinary tract urothelial carcinoma behaviors in patients with end-stage renal disease after kidney transplantation in Taiwan

PURPOSE

To determine upper urinary tract urothelial carcinoma (UT-UC) behavior in patients with end-stage renal disease (ESRD) after kidney transplantation (KT).

METHODS

From 2005 to 2012, 117 ESRD patients with localized UT-UC underwent nephroureterectomy at our institution. We divide these patients into two groups according to having had KT or not. Kaplan-Meier survival plot and multivariate analysis were used to evaluate whether kidney transplantation interfered with the UT-UC outcome.

RESULTS

The mean age was younger in ESRD with KT group (p = 0.001), but there was no difference in gender, smoking, or previous bladder cancer history between these two groups. The pathological features were more aggressive in ESRD with KT group compared to those without KT in regard to incidence of carcinoma in situ (p = 0.025) and multifocality (p = 0.001). Kidney transplantation did not interfere with the oncological outcome of UT-UC in ESRD patients. There were no differences in oncological outcome. Five-year metastasis-free survival rate was comparable.

CONCLUSION

In our sample, for patients with ESRD after kidney transplantation, the postoperative onset of UT-UC was younger and the pathological features were more aggressive. Standard surgical intervention resulted in satisfactory and similar outcome as did ESRD.

Chemotherapy for urothelial carcinoma in renal transplantation patients: Initial results from a single center

The aim of this study was to assess the safety and efficacy of gemcitabine plus cisplatin/carboplatin (GC/GCa) chemotherapy in renal transplantation (RT) patients with urothelial carcinoma (UC). We reviewed the records of 12 RT patients with metastatic or locally advanced UC who received chemotherapy at our institution since January, 2013. All the patients received intravenous gemcitabine (800 mg/m²) on days 1, 8 and 15, plus cisplatin (70 mg/m²) or carboplatin (area under the curve = 5) on day 2, every 28 days. A total of 10 patients completed all the cycles, while 1 patient discontinued treatment due to disease progression and 1 patient discontinued due to non-medical reasons. In total, 12 patients received a median of four cycles of chemotherapy. The overall response rate was 50% (4/8 cases) in patients with measurable lesions. At the time of the study, 5 patients had succumbed to the disease (overall survival, 9.2 months), while 7 patients remained alive (follow-up time, 13.3 months). The most common toxicities were myelosuppression and gastrointestinal effects. Therefore, the GC/GCa regimen was found to be effective and tolerable in RT patients with UC. However, further studies involving more patients and control groups are required to confirm our results.

Upper tract urothelial carcinomas in patients with chronic kidney disease: relationship with diagnostic challenge

Chronic kidney disease and upper tract urothelial carcinomas display a bidirectional relationship. Review of the literature indicates that early diagnosis and correct localization of upper tract urothelial carcinomas in dialysis patients and kidney transplant recipients are important but problematic. Urine cytology and cystoscopy have limited sensitivity for the diagnosis of upper tract urothelial carcinomas in dialysis patients. Enhanced computed tomography and magnetic resonance imaging could prove useful for the detection and staging of upper tract urothelial carcinomas in dialysis patients. Renal ultrasound can detect hydronephrosis caused by upper tract urothelial carcinomas in kidney transplant recipients but cannot visualize the carcinomas themselves. High detection rates for upper tract urothelial carcinomas in kidney transplant recipients have recently been demonstrated using computed tomography urography, which appears to be a promising tool. To detect carcinomas in dialysis patients and kidney transplant recipients as early as possible, regular screening in asymptomatic patients and diagnostic work-up in symptomatic patients should be performed using a combination of urological and imaging methods. Careful assessment of subsequent recurrence within the contralateral upper urinary tract and the urinary bladder is necessary for dialysis patients and kidney transplant recipients with upper tract urothelial carcinomas.