Cytospin performance when using Paris system for reporting urinary cytology

OBJECTIVES: The Paris System (TPS) for Reporting Urine Cytology has significantly improved the approach to evaluating urine cytology. TPS criteria were defined mainly according to ThinPrep and SurePath preparations, as they are widely utilized. The objective of this study is to validate urine cytology interpretation according to the TPS classification using cytospin technique in relation to the gold slandered histology. MATERIAL AND METHODS: This retrospective study examined and analyzed 316 urine specimens from King Abdulaziz University Hospital between 2015 and 2020. Cytospin technique is performed for all cases. Slides were recategorized using TPS criteria, then compared with the original histology diagnosis. RESULTS: According to the TPS, 108 cases were classified as 101 AUC (32%), 95 NEG (30%), 59 HGUC (18.7%), 31 SHGUC (9.8%), and 30 (9.5%) others. The computed sensitivity of cytospin in urine cytology was 94.7%, with 73.9% specificity, a positive predictive value of 85.6%, a negative predictive value of 89.5%, and overall accuracy of 86.8%. CONCLUSION: Urine cytology testing is considered to be a non-invasive and sensitive method to screen for urothelial carcinoma. TPS defined standards are reliable on cytospin prepared slides for reporting urine cytology.