Urinary tract cytology: a cytologic-histopathologic correlation with The Paris System, an institutional study

Are we on track for diagnosing high-grade urothelial carcinoma with a minimum quantity of five malignant cells in lower tract specimens? Critical analysis of The Paris System Quantitation Criteria

BACKGROUND

The Paris System for Reporting Urinary Cytology (TPS) has gained universal acceptance as the standard for reporting urine cytology requiring at least 5-10 malignant cells to diagnose high-grade urothelial carcinoma (HGUC) in lower and upper urinary tract specimens, respectively. These quantitation criteria are still subject to discussion, and this study specifically aims to validate the quantitation criterion of HGUC in lower urinary tract.

DESIGN

The authors reviewed two cohorts of lower urinary tract cases. The first cohort consisted of 100 liquid-based ThinPrep slides with the diagnosis of HGUC having positive histology on concurrent or follow-up biopsies within 3 months. The second cohort was 36 HGUC cases with negative histology on concurrent biopsies and within 3 months. The number of high-grade cells (HGCs) meeting the TPS qualitative criteria were counted under the light microscope driven in a grid-like manner.

RESULTS

The first 100 urine samples showed five cases (5.0%) with three HGCs, three cases (3.0%) had four HGCs, five cases (5.0%) showed five HGCs, and 25 cases (25.0%) had between 6-10 HGCs. The risk of high-grade malignancy (ROHM) in cases with five or more HGCs was 100%, whereas those with three HGCs was 60.0%. The second cohort of HGUC was considered "positive" despite a negative histology.

CONCLUSION

This study confirms that quantitation is an essential key to diagnose HGUC. The current TPS criterion of a minimum of five malignant cells in lower tract is robust with a ROHM of 100%. Diagnosing HGUC with less than five HGCs runs the risk of lowering the ROHM.

The Role of Novel Bladder Cancer Diagnostic and Surveillance Biomarkers-What Should a Urologist Really Know?

The aim of this review is to analyze and describe the current landscape of bladder cancer diagnostic and surveillance biomarkers. We researched the literature from 2016 to November 2021 to find the most promising new molecules and divided them into seven different subgroups based on their function and location in the cell. Although cystoscopy and cytology are still the gold standard for diagnosis and surveillance when it comes to bladder cancer (BCa), their cost is quite a burden for national health systems worldwide. Currently, the research is focused on finding a biomarker that has high negative predictive value (NPV) and can exclude with a certainty the presence of the tumor, considering missing it could be disastrous for the patient. Every subgroup has its own advantages and disadvantages; for example, protein biomarkers cost less than genomic ones, but on the other hand, they seem to be less precise. We tried to simplify this complicated topic as much as possible in order to make it comprehensible to doctors and urologists that are not as familiar with it, as well as encourage them to actively participate in ongoing research.

The Paris System for Reporting Urinary Cytology: A Meta-Analysis

The Paris System (TPS) for Reporting Urinary Cytology is a standardized, evidence-based reporting system, comprising seven diagnostic categories: nondiagnostic, negative for high-grade urothelial carcinoma (NHGUC), atypical urothelial cells (AUC), suspicious for high-grade urothelial carcinoma (SHGUC), HGUC, low-grade urothelial neoplasm (LGUN), and other malignancies. This study aimed to calculate the pooled risk of high-grade malignancy (ROHM) of each category and demonstrate the diagnostic accuracy of urine cytology reported with TPS. Four databases (PubMed, Embase, Scopus, Web of Science) were searched. Specific inclusion and exclusion criteria were applied, while data were extracted and analyzed both qualitatively and quantitatively. The pooled ROHM was 17.70% for the nondiagnostic category (95% CI, 0.0650; 0.3997), 13.04% for the NHGUC (95% CI, 0.0932; 0.1796), 38.65% for the AUC (95% CI, 0.3042; 0.4759), 12.45% for the LGUN (95% CI, 0.0431; 0.3101), 76.89 for the SHGUC (95% CI, 0.7063; 0.8216), and 91.79% for the HGUC and other malignancies (95% CI, 0.8722; 0.9482). A summary ROC curve was created and the Area Under the Curve (AUC) was 0.849, while the pooled sensitivity was 0.669 (95% CI, 0.589; 0.741) and false-positive rate was 0.101 (95% CI, 0.063; 0.158). In addition, the pooled DOR of the included studies was 21.258 (95% CI, 14.336; 31.522). TPS assigns each sample into a diagnostic category linked with a specific ROHM, guiding clinical management.

Application of the Paris Reporting System for Urine Cytology: The Three-Year Experience of a Single Tertiary Care Institute in Thailand

INTRODUCTION

Urothelial carcinoma is one of the most common human cancers, both in Thailand and worldwide. Urine cytology is a screening tool used to detect urothelial carcinoma. The Paris System for Reporting Urinary Cytology (TPSRUC) was first published in 2016 to standardize the procedures, reporting, and management of urothelial carcinoma. Diagnostic categories include negative for high-grade urothelial carcinoma (NHGUC), atypical urothelial cells (AUCs), suspicious for HGUC (SHGUC), HGUC, low-grade urothelial neoplasm, and other malignancies.

MATERIAL AND METHODS

In a retrospective review, urine cytology specimens from 2016 to 2019 were reevaluated using the TPSRUC. The risk of high-grade malignant neoplasm (ROHM) for each diagnostic category was calculated. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of prediction of high-grade malignant neoplasms were evaluated for cases with histological follow-up specimens.

RESULTS

In total, 2,178 urine cytology specimens were evaluated, of which 456 cases had follow-up histological specimens. The ROHM in each diagnostic category was as follows: NHGUC, 17.4%; AUC, 49.9%; SHGUC, 81.2%; HGUC, 91.3%; and other malignant neoplasms, 87.5%. The sensitivity, specificity, PPV, NPV, and accuracy for high-grade malignant neoplasm prediction were 63%, 92.8%, 89%, 73.1%, and 78.5% when AUC was included as malignant in the comparison and 82.6%, 74.7%, 75.1%, 82.3%, and 78.5% when AUC was not considered malignant.

CONCLUSIONS

TPSRUC provides reliable results that are reproducible by different interpreters and is a helpful tool for the detection of HGUC.