A review of urinary cytology in the setting of upper tract urothelial carcinoma

A urine-based liquid biopsy for detection of upper tract urothelial carcinoma: a self-matched study

BACKGROUND

To establish the pathological diagnosis of UTUC before treatment is profitable. At present, the conventional pathological diagnostic methods have certain problems. Besides, the urine-based DNA methylation test have been already utilized to detect bladder cancer.

OBJECTIVE

To evaluate the sensitivity and specificity of DNA methylation plus 17 genes mutation test and compare the combined test with cytology.

MATERIALS AND METHODS

We included 45 patients from April 2019 to May 2022, all of whom underwent radical nephroureterectomy (RNU), nephrectomy, diagnostic ureteroscopy or tissue biopsy. Before surgery, the urine samples were collected for DNA methylation plus 17 genes mutation test and cytology. The test performance was calculated, and comparative ROC curves were drawn.

RESULTS

The median age of the patients was 67 years. The Kappa value of the DNA methylation plus 17 genes mutation test and tissue pathology was 0.59 (p<0.001). The sensitivity/specificity/PPV/NPV of DNA methylation plus 17 genes mutation test was 86/80/94/62% compared with 29/100/100/29% for cytology. The AUC of DNA methylation plus 17 genes mutation test was 0.829 (p<0.001).The mutated gene proportion of UTUC patients was 51.43% for TERT and 25.71% for TP53.

CONCLUSION

The test performance of DNA methylation plus 17 genes mutation test was satisfactory, which may replace cytology in the future. Further multicenter studies with larger samples are needed to confirm the clinical value of this promising method.

NOVELTY & IMPACT STATEMENTS

We evaluated the diagnostic efficacy of a urine-based liquid biopsy for the detection of UTUC and compared the combined test with cytology. We found satisfactory results and concluded that the test could partly replace cytology. Further studies are needed.

Liquid Biopsy-Based Accurate Diagnosis and Genomic Profiling of Hard-to-Biopsy Tumors via Parallel Single-Cell Genomic Sequencing of Exfoliated Tumor Cells

Liquid biopsy provides a convenient and safer procedure for the diagnosis and genomic profiling of tumors that are inaccessible to biopsy by analyzing exfoliated tumor cells (ETCs) or tumor-derived cell-free DNA (cfDNA). However, its primary challenge lies in its limited accuracy in comparison to tissue-based approaches. We report a parallel single-ETC genomic sequencing (Past-Seq) method for the accurate diagnosis and genomic profiling of hard-to-biopsy tumors such as cholangiocarcinoma (CCA) and upper tract urothelial carcinoma (UTUC). For CCA, a prospective cohort of patients with suspicious biliary strictures (n = 36) was studied. Parallel single-cell whole genome sequencing and whole exome sequencing were performed on bile ETCs for CCA diagnosis and resolving mutational profiles, respectively, along with bile cfDNA sequenced for comparison. Concordant single-cell copy number alteration (CNA) profiles in multiple ETCs provided compelling evidence for generating a malignant diagnosis. Past-Seq yielded bile-based accurate CCA diagnosis (96% sensitivity, 100% specificity, and positive predictive value), surpassing pathological evaluation (56% sensitivity) and bile cfDNA CNA analysis (13% sensitivity), and generated the best performance in the retrieval tissue mutations. To further explore the applicability of Past-Seq, 10 suspicious UTUC patients were investigated with urine specimens, and Past-Seq exhibited 90% sensitivity in diagnosing UTUC, demonstrating its broad applicability across various liquid biopsies and cancer types.

Blood-based liquid biopsy: A promising noninvasive test in diagnosis, surveillance, and prognosis of patients with upper tract urothelial carcinoma

OBJECTIVES

To assess the efficacy of blood-based liquid biopsy in the diagnosis, surveillance, and prognosis of upper tract urothelial carcinoma (UTUC).

METHODS AND MATERIALS

In this prospective study, peripheral blood samples were collected from patients with primary UTUC before surgery with curative intent and follow-up visits at University of Southern California between May 2021 and September 2022. The samples were analyzed using the third-generation comprehensive high-definition single-cell assay (HDSCA3.0) to detect rare events, including circulating tumor cells (CTCs) and oncosomes, based on the immunofluorescence signals of DAPI (D), cytokeratin (CK), CD45/CD31 (CD), and vimentin (V). The findings of pre-surgery liquid biopsies were compared with those of blood samples from normal donors (NDs) and matched follow-up liquid biopsies. The association between liquid biopsy findings and clinical data, including recurrence-free survival (RFS), was also assessed.

RESULTS

Twenty-eight patients with UTUC were included, of whom 21 had follow-up samples. Significant differences in specific rare analytes were detected in the preoperative samples compared to the NDs. In the post- vs. presurgery matched analysis, a significant decrease was detected in total-, CK-, and CK|V oncosomes, as well as in D-, D|V-, and D|V|CD cells. With a median follow-up of 11 months, 8 patients had disease recurrence. Survival analysis demonstrated that patients with >1.95 preoperative CK|V oncosomes (p = 0.020) and those with >4.18 D|CK|V cells (p = 0.050) had worse RFS compared to other patients.

CONCLUSIONS

This study demonstrated promising initial evidence for the biomarker role of CTCs and oncosomes in the diagnosis and surveillance of patients with UTUC.

Large-scale Prospective Validation Study of a Multiplex RNA Urine Test for Noninvasive Detection of Upper Tract Urothelial Carcinoma

BACKGROUND

Current approaches for diagnosis and monitoring of upper tract urothelial carcinoma (UTUC) are often invasive, costly, and not efficient for early-stage and low-grade tumors.

OBJECTIVE

To validate a noninvasive urine-based RNA test for accurate UTUC diagnosis.

DESIGN, SETTING, AND PARTICIPANTS

Urine samples were prospectively collected from 61 patients with UTUC and 99 controls without urothelial carcinomas, in five clinical centers between October 2022 and August 2023 prior to any invasive test (cystoscope or ureteroscope) or treatment. All samples were analyzed with a urine-based RNA test composed of eight genes (CA9, CCL18, ERBB2, IGF2, MMP12, PPP1R14D, SGK2, and SWINGN). The test results were presented with a risk score for each participant, which was applied to categorize patients into low- or high-risk groups.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The diagnosis of UTUC was based mainly on preoperative radiological examination criteria and confirmed by postoperative pathological results. The recursive feature elimination and support vector machine algorithms, χ2, and Student t test were used.

RESULTS AND LIMITATIONS

The eight-gene urine test accurately detected UTUC patients and controls with an area under the curve (AUC) of 0.901 in a single-center testing cohort (n = 93) and an AUC of 0.926 in a multicenter clinical validation cohort (n = 66). In the merged validation cohort, the eight-gene urine test achieved high sensitivity of 90.16%, specificity of 88.89%, and overall accuracy of 89.38%. Remarkably, excellent performance was achieved in 11 low-grade UTUC patients with accuracy of 100%. However, this study collected the urine of UTUC patients only at a single preoperative time point and did not perform continuous tests during the pathological process of UTUC in the surveillance population.

CONCLUSIONS

Our results demonstrated that the eight-gene urine test can differentiate accurately between UTUC and other urological diseases with high sensitivity and specificity. In clinical practice, it may be used for identifying UTUC patients effectively, leading to reduced reliance on ureteroscopy and blind surgery.

PATIENT SUMMARY

In this study, we investigated a multiplex RNA urine test for noninvasive upper tract urothelial carcinoma (UTUC) diagnosis before treatment. We found that the risk scores derived from the multiplex RNA urine test differed significantly between UTUC patients and corresponding controls.

Do Urine Cytology and FISH Analysis Have a Role in the Follow-Up Protocol of Upper Tract Urothelial Carcinoma?

BACKGROUND

Current guidelines recommend a stringent follow-up regimen that includes interval cystoureteronephscopy, CT urography, and selective urine cytology sampling for upper tract urothelial carcinoma (UTUC) patients undergoing endoscopic treatment and management. There are no recommendations regarding FISH analysis. Our purpose was to assess the efficacy of cytology and FISH as part of the follow-up protocol and its significance to clinical decision-making in this scenario.

METHODS

The medical records of all patients who managed endoscopically for UTUC at our institute between 2014 and 2022 were retrospectively analyzed. Demographic and clinical data, histology, cytology, and FISH results were collected. FISH analysis was considered malignant according to Paris criteria.

RESULTS

During the study period, 62 patients underwent 561 ureteroscopies as part of the treatment and follow-up regimen of low-grade UTUC. Urine from the affected upper tract was sampled for cytology in 377 procedures, and FISH analyses were performed in 273. In 75.4% of FISH analyses, the result was different from the cytology results: FISH found malignant aberrations in 15.5% of cases where cytology was benign. Furthermore, FISH classified all the cells defined as atypical via cytology as either benign or malignant. In only one case (0.17%), the urinary cytology report changed the follow-up regimen.

CONCLUSION

Cytology may be omitted from the follow-up protocol of low-grade UTUC. In the handful of cases cytology does assist the diagnosis of UTUC, there is an additional benefit to performing FISH analysis, particularly when cellular atypia is reported in the cytology results.

Head-to-head comparisons of 68Ga-PSMA-11 and 18F-FDG PET/CT in evaluating patients with upper tract urothelial carcinoma: a prospective pilot study

PURPOSE

To prospectively compare the uptake of 68Ga-prostate specific membrane antigen (68Ga-PSMA)-11 and 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in upper tract urothelial carcinoma (UTUC) and investigate the correlation between radiological parameters and pathological features of UTUC.

METHODS

Clinicopathologic and imaging data were collected from 10 UTUC patients who underwent preoperative 68Ga-PSMA-11 and 18F-FDG PET/CT scans. The diagnostic capabilities of both imaging techniques were analyzed and compared in UTUC. Angiogenesis in the malignancies was assessed using Chalkley counting and the expression of folate hydrolase 1 (FOLH1) and glucose transporter 1 (GLUT1) in UTUC were evaluated in the surgical specimens. Double immunofluorescence staining of PSMA and CD34 was used to examine tumor neovascularization. Tracer uptake and expression were compared and explored. Additionally, 10 patients with clear cell renal cell carcinoma (ccRCC) were included for prospective, comparative research.

RESULTS

Ten UTUC patients with 12 malignant lesions and another 10 ccRCC patients were included. 18F-FDG PET/CT demonstrated a more effective detection of UTUC foci compared to 68Ga-PSMA-11 PET/CT (the SUVmax of 18.48 ± 6.73 vs. 4.38 ± 1.45, P < 0.01). Immunohistochemical analysis revealed a statistically significant difference in the expression of PSMA and GLUT1 in UTUC (P = 0.048), with higher pathological grades showing more intense GLUT1 staining than PSMA (75% vs. 12.5%). The Chalkley counting of angiogenesis in ccRCC was significantly higher than that in UTUC (229.34 vs. 71.67), which was proportional to 68Ga-PSMA-11 PET/CT SUVmax (both P < 0.05).

CONCLUSION

18F-FDG PET/CT holds better clinical potential for evaluating UTUC and detecting lymph node metastasis compared to 68Ga-PSMA-11 PET/CT, likely due to the relatively scant expression of FOLH1 in tumor neovascular endothelium while the abundant expression of GLUT1 in malignancy. Furthermore, the lower neovascular density in UTUC should not be overlooked.

Feasibility and tissue concordance of genomic sequencing of urinary cytology in upper tract urothelial carcinoma

BACKGROUND

There is limited ability to accurately diagnose and clinically stage patients with upper tract urothelial carcinoma (UTUC). The most easily available and widely used urinary biomarker is urine cytology, which evaluates cellular material yet lacks sensitivity. We sought to assess the feasibility of performing next-generation sequencing (NGS) on urine cytology specimens from patients with UTUC and evaluate the genomic concordance with tissue from primary tumor.

METHODS

In this retrospective study, we identified 48 patients with a diagnosis of UTUC treated at Memorial Sloan Kettering Cancer Center (MSK) between 2019 and 2022 who had banked or fresh urine samples. A convenience cohort of matching, previously sequenced tumor tissue was used when available. Urine specimens were processed and the residual material, including precipitated cell-free DNA, was sequenced using our tumor-naïve, targeted exome sequencing platform that evaluates 505 cancer-related genes (MSK-IMPACT). The primary outcome was at least 1 detectable mutation in urinary cytology specimens. The secondary outcome was concordance to matched tissue (using ANOVA or Chi-Square, as indicated).

RESULTS

Genomic sequencing was successful for 45 (94%) of the 48 urinary cytology patient samples. The most common mutations identified were TERT (62.2%), KMT2D (46.7%), and FGFR3 (35.6%). All patients with negative urine cytology and low-grade tissue had successful cytology sequencing. Thirty-six of the 45 patients had matching tumor tissue available; concordance to matched tissue was 55% overall (131 of the total 238 oncogenic or likely oncogenic somatic mutations identified). However, in 94.4% (n = 34/36) of patients, the cytology had at least 1 shared mutation with tissue. Eleven (30.6%) patients had 100% concordance between cytology and tissue.

CONCLUSIONS

Sequencing urinary specimens from selective UTUC cytology is feasible in nearly all patients with UTUC. Prospective studies are underway to investigate a clinical role for this promising technology.

MCM4 expression is associated with high-grade histology, tumor progression and poor prognosis in urothelial carcinoma

BACKGROUND

We previously reported Minichromosome maintenance 4 (MCM4) overexpression in gastric cancer. However, the clinicopathological significance of MCM4 in urothelial carcinoma (UC) has not been investigated. To clarify the clinicopathological significance of MCM4 in UC, we investigated MCM4 expression with immunohistochemistry (IHC).

METHODS

We analyzed the expression and distribution of MCM4 in 124 upper tract urothelial carcinoma (UTUC) samples by IHC. Additionally, using 108 urine samples, we analyzed MCM4 Immunocytochemistry (ICC) expression in urine cytology.

RESULTS

In normal urothelium, MCM4 expression was weak or absent. Meanwhile, the strong nuclear expression of MCM4 was observed in UTUC tissues, and it was detected in 77 (62%) of a total of 124 UTUC cases. MCM4-positive UTUC cases were associated with nodular/flat morphology, high grade, high T stage, and poor prognosis. Moreover, MCM4 expression was significantly higher in the invasive front than in the tumor surface. Similar results were also obtained in TCGA bladder cancer cohort. Additionally, MCM4 expression was associated with high expression of Ki-67, HER2, EGFR, and p53 in UTUC. Among representative cancer-related molecules, MCM4 had an independent predictive value for progression-free survival and high-grade UC. ICC for MCM4 was also performed on urine cytology slides and showed that the nuclear expression of MCM4 was more frequently found in UC cells than in non-neoplastic cells. The diagnostic accuracy of urine cytology was improved by combining MCM4 immunostaining with cytology.

CONCLUSION

These results suggest that MCM4 might be a useful predictive biomarker for high-grade histology, tumor progression and poor prognosis in UC. Moreover, ICC for MCM4 might be helpful for UC detection as additional markers in the cytomorphology-based diagnosis.

Clinicopathological significance of TUBB3 in upper tract urothelial carcinoma and possible application in urine cytology

βIII-Tubulin, encoded by the TUBB3 gene, is a microtubule protein. We previously reported that TUBB3 is overexpressed in renal cell carcinoma. We investigated the clinicopathological significance of TUBB3 in upper tract urothelial carcinoma (UTUC) by immunohistochemistry. In normal tissue, TUBB3 expression was weak or absent. In contrast, TUBB3 overexpression was observed in urothelial carcinoma (UC) tissues in 51 (49%) of 103 UTUC cases. TUBB3 overexpression was associated with nodular/flat morphology, high-grade disease, high T stage, and a poor prognosis. Similar results were obtained in The Cancer Genome Atlas bladder cancer cohort. TUBB3 expression was also associated with high Ki-67 labeling index, CD44v9, HER2, EGFR, and p53 expression in UTUC. Among representative cancer-related molecules, TUBB3 was an independent predictor of progression-free survival and high-grade UC. Finally, using urine cytology samples, we analyzed TUBB3 expression by immunocytochemistry. TUBB3 expression was more frequently found in UC cells than in nonneoplastic cells. The diagnostic accuracy of urine cytology was improved when combined with TUBB3 immunostaining. The findings suggest the importance of TUBB3 in tumor progression and its potential application as a biomarker for high-grade disease and the prognosis of UC. Moreover, combination with TUBB3 immunostaining might improve the diagnostic accuracy of urine cytology.

Dual immunocytochemical staining of annexin A10 and p53 in low-grade and papillary urothelial carcinoma contributes to improvement of diagnostic accuracy in urine cytology

BACKGROUND

Urothelial carcinoma (UC) is a common type of human cancer and, although urine cytology is a useful method for identifying high-grade UC (HGUC), its ability to diagnose low-grade UC (LGUC) is limited. The authors previously reported that annexin A10 (ANXA10) expression was strongly linked to both papillary and early stage LGUC and was inversely correlated with p53 expression in upper tract UC (UTUC) and bladder UC. However, it remains largely unknown whether ANXA10 is useful as a diagnostic marker for urine cytology.

METHODS

In this study, the authors used 104 biopsy and 314 urine cytology samples to investigate the efficacy of ANXA10 and p53 expression by immunohistochemistry and immunocytochemistry.

RESULTS

In immunohistochemistry analysis, expression levels of ANXA10 and p53 were either weak or absent in noncancerous tissues, whereas ANXA10 overexpression was observed patients with LGUC, and strong expression of p53 was identified in patients with HGUC. In immunocytochemistry analysis, sensitivity was not good for the detection of UC, especially UTUC, by cytology alone, but it was improved by combining cytology with ANXA10 and p53 to detect both bladder UC and UTUC. Receiver operating characteristic curve analysis also confirmed the diagnostic superiority of cytology combining ANXA10 and p53 for the detection of all UCs, including both HGUC and LGUC (area under the curve, 0.84).

CONCLUSIONS

To the authors' knowledge, this is the first report that the combination of ANXA10 and p53 has potential application as a diagnostic immunomarker for improving the diagnostic accuracy of urine cytology.

Diagnosis of Low-Grade Urothelial Neoplasm in the Era of the Second Edition of the Paris System for Reporting Urinary Cytology

BACKGROUND

The Paris System for Reporting Urinary Cytology (TPS) is considered the gold standard when it comes to diagnostic classifications of urine specimens. Its second edition brought some important changes, including the abolition of the diagnostic category of "low-grade urothelial neoplasm (LGUN)", acknowledging the inability of cytology to reliably discern low-grade urothelial lesions.

METHODS

In this retrospective study, we assessed the validity of this change, studying the cytological diagnoses of histologically diagnosed low-grade urothelial carcinomas during a three-year period. Moreover, we correlated the sum of the urinary cytology diagnoses of this period with the histological diagnoses, whenever available.

RESULTS

Although all the cytological diagnoses of LGUN were concordant with the histological diagnoses, most low-grade urothelial carcinomas were misdiagnosed cytologically. Subsequently, the positive predictive value (PPV) of urinary cytology for the diagnosis of LGUN was 100%, while the sensitivity was only 21.7%. Following the cyto-histopathological correlation of the sum of the urinary cytology cases, the sensitivity of urinary cytology for the diagnosis of high-grade urothelial carcinoma (HGUC) was demonstrated to be 90.1%, the specificity 70.8%, the positive predictive value (PPV) 60.3%, the negative predictive value (NPV) 93.6% and the overall accuracy 77.2%, while for LGUN, the values were 21.7%, 97.2%, 87.5%, 58.6% and 61.9%, respectively. Risk of high-grade malignancy was 0% for the non-diagnostic (ND), 4.8% for the non-high-grade urothelial carcinoma (NHGUC), 33.3% for the atypical urothelial cells (AUCs), 65% for the suspicious for high-grade urothelial carcinoma (SHGUC), 100% for the HGUC and 12.5% for the LGUN diagnostic categories.

CONCLUSIONS

This study validates the incorporation of the LGUN in the NHGUC diagnostic category in the second edition of TPS. Moreover, it proves the ability of urinary cytology to safely diagnose HGUC and stresses the pivotal role of its diagnosis.

Cutoff values of PD-L1 expression in urinary cytology samples for predicting response to immune checkpoint inhibitor therapy in upper urinary tract urothelial carcinoma

BACKGROUND

The objective of this study was to determine the cutoff value of PD-L1 expression that can predict response to immune checkpoint inhibitor (ICI) immunotherapy for upper tract urothelial carcinoma (UTUC).

METHODS

The concordance of PD-L1 expression between paired surgical resection specimens (SRSs) and urine cell blocks (UCBs) (cohort 1) was studied in a retrospective set of 58 UTUC patients to determine its suitability as a predictor of ICI immunotherapy efficacy. PD-L1 expression in UCBs obtained before neoadjuvant ICI immunotherapy was verified in a prospective set of 12 UTUC patients (cohort 2). PD-L1 (SP263 clone) expression was assessed for percentage (tumor proportional score) of tumor cell (TC) showing PD-L1 staining.

RESULTS

The authors found an overall agreement of 94.4% (51 of 54) between UCBs and SRSs in cohort 1 (positive percent agreement = 100%, negative percent agreement = 93.8%, r value = 0.63). PD-L1 expression in <10% and ≥10% of tumor cells (TCs) of UCBs were the best predictors of negative (<25%) and positive (≥25%) expression in TCs of SRSs, respectively (concordance = 98.1%, r value = 0.93). These findings were verified in cohort 2: at the 10% cutoff for PD-L1 expression, the best response predictive value was 83.3% (5 of 6) in PD-L1-positive patients, and the nonresponse predictive value was 50% (3 of 6) in PD-L1-negative patients. The sensitivity, specificity, and area under the receiver operating characteristic curve values for predicting ICI immunotherapy efficacy based on PD-L1-expressing TCs in UCBs were 62.5%, 75%, and 0.688, respectively.

CONCLUSIONS

Immunocytochemistry of UCBs is reliable for determining PD-L1 expression, which can predict the efficacy of ICI immunotherapy at a cutoff of 10%.

Clinicopathological significance of the overexpression of MUC1 in upper tract urothelial carcinoma and possible application as a diagnostic marker

Mucin 1 (MUC1) overexpression has been reported in many malignancies and is associated with a poor prognosis. However, the clinicopathological significance of MUC1 in upper tract urothelial carcinoma (UTUC) has not been investigated. We analyzed the expression and distribution of MUC1 in UTUC by immunohistochemistry. In normal urothelium, MUC1 expression was observed on the surface of umbrella cells. Meanwhile, the strong expression of MUC1 was observed in cell membranes and cytoplasm in UTUC tissues, and it was detected in 64 (58%) of a total of 110 UTUC cases. MUC1-positive UTUC cases were associated with nodular/flat morphology, high grade, high T stage, and lymphatic and venous invasion and poor prognosis. Additionally, MUC1 expression was associated with high expression of Ki-67, programmed death-ligand 1 (PD-L1), CD44 variant 9 (CD44v9), human epidermal growth factor receptor 2 (HER2), epidermal growth factor receptor (EGFR), and p53 in UTUC. Furthermore, immunocytochemistry for MUC1 on urine cytology slides demonstrated that the strong staining of MUC1 was more frequently found in tumor cells than in nonneoplastic cells. The diagnostic accuracy of urine cytology was improved by combining MUC1 immunostaining with cytology. These results suggest that MUC1 may be a prognostic biomarker in UTUC, and MUC1 exression has a potential application as a diagnostic immunomarker for urine cytology.

The Diagnostic Dilemma of Urothelial Tissue Fragments in Urinary Tract Cytology Specimens

Since the release of The Paris System for Reporting Urinary Cytology (TPS), the assessment of urine cytology specimens has primarily focused on the detection of high-grade urothelial carcinoma (HGUC) and carcinoma in situ (CIS). Fortunately, the malignant cells in these lesions tend to be loosely cohesive, resulting in the natural exfoliation of individual malignant cells into the urine. However, HGUC/CIS lesions occasionally exfoliate larger fragments which can be difficult to assess due to cellular overlap and fragment three-dimensionality. Furthermore, reactive benign urothelial fragments and fragments from low-grade urothelial neoplasms (LGUN) may also be seen in urine specimens and contain atypical cytomorphologic features. As a result, the significance of urothelial tissue fragments (UTFs) is often unclear. Herein, we discuss the literature on UTFs before and after the implementation of TPS, as well as strategies to help overcome this diagnostic challenge.

Indeterminate atypia in urinary tract cytology: Does it really matter?

The study of atypia in urinary cytology has been ongoing for decades but most studies have focused primarily on test performance in patients with concurrent biopsies and/or limited follow-up periods. While these data are useful, many studies fail to consider patient factors that may alter the pretest probability, which can subsequently affect test performance. An isolated diagnosis of malignancy in urinary cytology usually has a high positive predictive value and allows a urologist to conduct a rigorous workup of the patient to establish a tissue diagnosis. However, it is less certain how an atypical diagnosis impacts patient care, given that many patients have a history of bladder cancer and are already under surveillance with cystoscopy at regular screening intervals. Furthermore, a discrete negative urine cytology is unlikely to allow a patient to forego a cystoscopy procedure due to limitations in the sensitivity of urine cytology. Over the last several years, the introduction of The Paris System for Reporting Urinary Cytology (TPS) has improved the predictive value of atypical diagnoses, but additional studies are needed to evaluate the performance of these diagnoses in specific clinical situations. Such data could better inform urologists on how to manage patients with atypical diagnoses. This review discussed the diagnosis of atypia in urinary cytology and the impact of such a diagnosis in various clinical contexts.

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.