The primary purpose of urinary cytology is to detect high-grade urothelial carcinoma (HGUC).

The Paris System working group, consisting of cytopathologists, anatomo-pathologists and urologists proposed and published a standardized reporting system that includes specific diagnostic categories and cytomorphological criteria for a reliable HCUG diagnosis.

The Paris System for Reporting Urinary Cytology (TPS) was first published in 2016 with the clear goal of standardizing cytologic diagnostic criteria and providing uniform reporting in order to improve patient classification and associated clinical management.

Since the introduction of TPS, there is an improvement in the screening potential and surveillance of urinary cytology, with a reduction in the high rates of unknow diagnoses, improving sensitivity and providing a proper risk classification for patients.

The parameters that define adequacy in urinary cytology are the cellularity and the volume of urine submitted for analysis; 30 ml appears to be a reasonable volume to minimize the number of inadequate samples and identify high-grade urothelial carcinoma (HGUC).

• Barkan GA, Wojcik EM, Nayar R, Savic-Prince S, Quek ML, Kurtycz DF, Rosenthal DL. The Paris System for Reporting Urinary Cytology: The Quest to Develop a Standardized Terminology. Adv Anat Pathol. 2016 Jul;23(4):193-201. doi: 10.1097/PAP.0000000000000118. PMID: 27233050.
• Pastorello RG, Barkan GA, Saieg M. Experience on the use of The Paris System for Reporting Urinary Cytopathology: review of the published literature. J Am Soc Cytopathol. 2021 Jan-Feb;10(1):79-87. doi: 10.1016/j.jasc.2020.10.002. Epub 2020 Oct 10. PMID: 33160893.
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