Impact of Implementing the Paris System for Reporting Urinary Cytology: A Single-institutional Experience With Emphasis on Diagnostic Yield of High-grade Urothelial Carcinoma and Low-grade Urothelial Neoplasm

摘要

Background/Aim: The Paris System (TPS) has recently been proposed as a method to standardize urinary cytology reporting. In this study, we evaluated the impact of implementing TPS compared to the traditional reporting system. Patients and Methods: In total, 299 urine samples were reclassified according to TPS. We examined correlations between cytological and histological diagnoses, and calculated probabilities for detecting high-grade urothelial carcinoma (HGUC). Results: TPS resulted in a decrease in the proportion of cases diagnosed as atypical urothelial cell (AUC) (43% to 31%). Among the AUC cases, the proportion of histologically confirmed HGUC cases rose (75% to 80%), as did the proportion of low-grade urothelial neoplasms (57% to 71%). All probabilities for detecting HGUC significantly increased using TPS. Conclusion: TPS improved the diagnostic yield of urinary cytology. The implementation of TPS is expected to be a major step towards standardizing urinary cytology reporting and providing clear information to clinicians.