Higher risk of urothelial carcinoma in the upper urinary tract than in the urinary bladder in hemodialysis patients

Liquid biopsy in urothelial carcinoma: Detection techniques and clinical applications

The types of urothelial carcinoma (UC) include urothelial bladder cancer and upper tract urothelial carcinoma. Current diagnostic techniques cannot meet the needs of patients. Liquid biopsy is an accurate method of determining the molecular profile of UC and is a cutting-edge and popular technique that is expected to complement existing detection techniques and benefit patients with UC. Circulating tumor cells, cell-free DNA, cell-free RNA, extracellular vesicles, proteins, and metabolites can be found in the blood, urine, or other bodily fluids and are examined during liquid biopsies. This article focuses on the components of liquid biopsies and their clinical applications in UC. Liquid biopsies have tremendous potential in multiple aspects of precision oncology, from early diagnosis and treatment monitoring to predicting prognoses. They may therefore play an important role in the management of UC and precision medicine.

New Hydronephrosis in the Native Kidney Is Associated with the Development of De Novo Urinary Bladder Urothelial Carcinoma in Patients with Post-Kidney Transplantation

Increased malignancy after kidney transplantation (KT) is by far the most troublesome issue. Among these malignancies, urothelial carcinoma (UC) incidence is uniquely high in Taiwan. We want to know whether routine sonography to detect native hydronephrosis is associated with the development of de novo urinary bladder urothelial carcinoma (UBUC) in post-KT recipients. From 2003 to 2018, we retrospectively analyzed 1005 KT patients, 58 of whom were subsequently diagnosed with UBUC. The association between new native hydronephrosis and post-KT UBUC was analyzed with univariate and multivariate logistic regression analyses and a Kaplan-Meier plot. We excluded cases of people who had upper urinary tract urothelial carcinoma (UTUC) and were diagnosed prior to UBUC. There were 612 males (60.9%) and 393 females (39.1%), with a mean age of 48.2 ± 12.0 years old at KT. The mean follow-up period was 118.6 ± 70.2 months, and the diagnosis of UBUC from KT to UBUC was 7.0 ± 5.1 years. New native kidney hydronephrosis occurred more frequently in the UBUC group (56.4% versus 6.4%, p < 0.001) than the non-UBUC group. Multivariate analysis disclosed that native hydronephrosis is the only statistically significant factor for UBUC, with an odds ratio of 16.03 (95% CI, 8.66-29.68; p < 0.001). UBUC in post-KT patients with native hydronephrosis also showed a tendency toward multifocal lesions upon presentation (47.8%). Post-KT UBUC is characterized by pathologically aggressive and multiple foci lesions. Native kidney hydronephrosis may be a deciding factor of post-KT UBUC.

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.

Copy Number Signatures and Clinical Outcomes in Upper Tract Urothelial Carcinoma

Tumor staging of upper tract urothelial carcinomas (UTUCs) is relatively difficult to assert accurately before surgery. Here, we used copy number (CN) signatures as a tool to explore their clinical significance of molecular stratification in UTUC. CN signatures were extracted by non-negative matrix factorization from the whole-genome sequencing (WGS) data of 90 Chinese UTUC primary tumor samples. A validation UTUC cohort (n = 56) and a cohort from urinary cell-free DNA (cfDNA) of urothelial cancer patients (n = 94) and matched primary tumors were also examined. Survival analyses were measured using the Kaplan–Meier, and Cox regression was used for multivariate analysis. Here, we identified six CN signatures (Sig1–6). Patients with a high contribution of Sig6 (Sig6high) were associated with higher microsatellite instability level and papillary architecture and had a favorable outcome. Patients with a low weighted genome integrity index were associated with positive lymph node and showed the worst outcome. Sig6high was identified to be an independently prognostic factor. The predictive significance of CN signature was identified by a validation UTUC cohort. CN signatures retained great concordance between primary tumor and urinary cfDNA. In conclusion, our results reveal that CN signature assessment for risk stratification is feasible and provides a basis for clinical studies that evaluate therapeutic interventions and prognosis.

The incidence and prevalence of upper tract urothelial carcinoma: a systematic review

BACKGROUND

Upper tract urothelial carcinoma (UTUC) is a rare urological cancer that is still an important public health concern in many areas around the world. Although UTUC has been linked to a number of risk factors, to our knowledge no systematic review has been published on the overall incidence and prevalence of de-novo UTUC. This review aimed to examine the global epidemiology of UTUC to provide clinicians and public health specialists a better understanding of UTUC.

METHODS

A systematic search was conducted on MEDLINE, Embase, and the Web of Science using a detailed search strategy. Observational epidemiological studies describing the incidence and prevalence of de-novo UTUC in adults were included, and the Joanna Briggs Institute checklist was used for critical appraisal and data extraction of the studies selected.

RESULTS

The systematic search identified 3506 papers, of which 59 papers were included for qualitative synthesis. The studies selected included data ranging from the years 1943 to 2018. A comprehensive qualitative synthesis of the data was performed. UTUC incidence generally varied according to age (higher with increasing age), sex (unclear), race (unclear), calendar time (increased, stable, or decreased according to region), geographical region (higher in Asian countries), occupation (higher in seamen and printers), and other population characteristics. Prevalence was only reported by one study, which showed UTUC to have the highest incidence of the rare urogenital cancers in Europe.

CONCLUSION

This systematic review highlights an increased incidence of UTUC in certain groups, including increasing age and certain occupations such as seamen. The incidence of UTUC also varies between certain geographical regions. The trend of UTUC incidence for sex, race, and calendar time is less clear due to a wide variety of metrics used by the studies identified. More studies are also required on the prevalence of UTUC to understand its disease burden. Trial registration This review was registered on PROSPERO (registration number CRD42019134255).

Urothelial Carcinoma Detection Based on Copy Number Profiles of Urinary Cell-Free DNA by Shallow Whole-Genome Sequencing

BACKGROUND

Current noninvasive assays for urothelial carcinoma (UC) lack clinical sensitivity and specificity. Given the utility of plasma cell-free DNA (cfDNA) biomarkers, the development of urinary cfDNA biomarkers may improve the diagnostic sensitivity.

METHODS

We assessed copy number alterations (CNAs) by shallow genome-wide sequencing of urinary cfDNA in 95 cancer-free individuals and 65 patients with UC, 58 with kidney cancer, and 45 with prostate cancer. We used a support vector machine to develop a diagnostic classifier based on CNA profiles to detect UC (UCdetector). The model was further validated in an independent cohort (52 patients). Genome sequencing data of tumor specimens from 90 upper tract urothelial cancers (UTUCs) and CNA data for 410 urothelial carcinomas of bladder (UCBs) from The Cancer Genome Atlas were used to validate the classifier. Genome sequencing data for urine sediment from 32 patients with UC were compared with cfDNA. To monitor the treatment efficacy, we collected cfDNA from 7 posttreatment patients.

RESULTS

Urinary cfDNA was a more sensitive alternative to urinary sediment. The UCdetector could detect UC at a median clinical sensitivity of 86.5% and specificity of 94.7%. UCdetector performed well in an independent validation data set. Notably, the CNA features selected by UCdetector were specific markers for both UTUC and UCB. Moreover, CNA changes in cfDNA were consistent with the treatment effects. Meanwhile, the same strategy could localize genitourinary cancers to tissue of origin in 70.1% of patients.

CONCLUSIONS

Our findings underscore the potential utility of urinary cfDNA CNA profiles as a basis for noninvasive UC detection and surveillance.

Aristolochic acid mutational signature defines the low-risk subtype in upper tract urothelial carcinoma

Rationale: Dietary exposure to aristolochic acids and similar compounds (collectively, AA) is a significant risk factor for nephropathy and subsequent upper tract urothelial carcinoma (UTUC). East Asian populations, who have a high prevalence of UTUC, have an unusual genome-wide AA-induced mutational pattern (COSMIC signature 22). Integrating mutational signature analysis with clinicopathological information may demonstrate great potential for risk ranking this UTUC subtype.

Methods: We performed whole-genome sequencing (WGS) on 90 UTUC Chinese patients to extract mutational signatures. Genome sequencing data for urinary cell-free DNA from 26 UTUC patients were utilized to noninvasively identify the mutational signatures. Genome sequencing for primary tumors on 8 out of 26 patients was also performed. Metastasis-free survival (MFS) and cancer-specific survival (CSS) were measured using Kaplan-Meier methods.

Results: Data analysis showed that a substantial proportion of patients harbored the AA mutational signature and were associated with AA-containing herbal drug intake, female gender, poor renal function, and multifocality. Field cancerization was found to partially contribute to multifocality. Nevertheless, AA Sig subtype UTUC patients exhibited favorable outcomes of CSS and MFS compared to the No-AA Sig subtype. Additionally, AA Sig subtype patients showed a higher tumor mutation burden, higher numbers of predicted neoantigens, and infiltrating lymphocytes, suggesting the potential for immunotherapy. We also confirmed the AA signature in AA-treated human renal tubular HK-2 cells. Notably, the AA subtype could be ascertained using a clinically applicable sequencing strategy (low coverage) in both primary tumors and urinary cell-free DNA as a basis for therapy selection.

Conclusion: The AA mutational signature as a screening tool defines low-risk UTUC with therapeutic relevance. The AA mutational signature, as a molecular prognostic marker using either ureteroscopy and/or urinary cell-free DNA, is especially useful for diagnostic uncertainty when kidney-sparing treatment and/or immune checkpoint inhibitor therapy were considered.

Association between urologic malignancies and end-stage renal disease: A meta-analysis

AIM

Previous studies have suggested a higher incidence of urologic malignancies in end-stage renal disease (ESRD) patients. However, incidence trends of urologic malignancies in ESRD patients remain unclear. The aims of the present study were: (i) to investigate the pooled incidence/incidence trends; and (ii) to assess the risk of urologic malignancies in ESRD patients.

METHODS

A literature search was conducted using MEDLINE, EMBASE and Cochrane Database from inception through April 2017. Studies that reported incidence or odds ratios of urologic malignancies among ESRD patients were included. Pooled odds ratios (OR) and 95%CI were calculated using a random-effect model. The protocol for this meta-analysis is registered with PROSPERO (International Prospective Register of Systematic Reviews; no. CRD42017067687).

RESULTS

Nineteen observational studies with 1 931 073 ESRD patients were enrolled. The pooled estimated incidence of kidney cancer and urothelial cancers (carcinomas of the bladder, ureters, and renal pelvis) in ESRD patients were 0.3% (95%CI: 0.2-0.5%) and 0.5% (95%CI: 0.3-0.8%), respectively. Meta-regression showed significant positive correlation between incidence of urologic malignancies in ESRD patients and year of study (slopes = +0.05 and +0.07, P < 0.001 for kidney cancer and urothelial cancers, respectively). Compared to non-ESRD status, ESRD was significantly associated with both kidney cancer (pooled OR 6.04; 95% CI 4.70-7.77) and urothelial cancers (pooled OR 4.37; 95% CI 2.40-7.96).

CONCLUSION

Our study demonstrates a significant association between ESRD and urologic malignancies. The overall estimated incidence rates of kidney cancer and urothelial cancers are 0.4% and 0.5%, respectively. There is a significant positive correlation between the incidence of urologic malignancies and year of study.

Outcomes of stage II-IV upper-tract urothelial carcinoma and adjuvant chemotherapy for locally advanced cancer

The present retrospective study aimed to examine the outcomes of stage II-IV upper-tract urothelial carcinoma (UTUC) and determine whether adjuvant chemotherapy is a beneficial treatment for patients with locally advanced UTUC (specifically, stage III-IV). The analysis included 126 patients with muscle-invasive UTUC who were treated between June 2003 and June 2012. All patients underwent laparoscopic or open nephroureterectomy and bladder cuff excision. Overall survival (OS), disease-free survival (DFS), distant metastasis-free survival (DMFS) and locoregional recurrence-free survival (LRFS) were assessed. Outcomes were compared between groups of patients with stage II (high-stage localized) disease, stage III-IV (high-stage locally advanced) disease treated with chemotherapy, and stage III-IV disease not treated with chemotherapy. Among patients with high-stage locally advanced UTUC (stage III-IV), those who received adjuvant chemotherapy had significantly better rates of OS (67.1 vs. 33.7%; P=0.004), DFS (70.2 vs. 46.0%; P=0.030) and DMFS (86.3 vs. 65.2%; P=0.048) at 5-years compared with those who did not undergo adjuvant chemotherapy. However, there was no significant difference between the 5-year LRFS rates in these two groups (78.2 vs. 62.5%; P=0.525). Importantly, the survival curve of patients with high-stage UTUC who received adjuvant chemotherapy was similar to that of patients with low-stage UTUC who underwent surgery only. Multivariate analysis revealed that adjuvant chemotherapy was an independent risk factor for OS [without adjuvant chemotherapy vs. with adjuvant chemotherapy: Hazard ratio (HR), 0.29; 95% confidence interval (CI), 0.129-0.654; P=0.003] and DFS (without adjuvant chemotherapy vs. with adjuvant chemotherapy: HR, 0.381; 95% CI, 0.168-0.865; P=0.021). In conclusion, adjuvant chemotherapy may improve the outcome for patients with high-stage locally advanced UTUC.