Implementing The Paris System for Reporting Urinary Cytology results in a decrease in the rate of the "atypical" category and an increase in its prediction of subsequent high-grade urothelial carcinoma

Cancer Cytopathol. 2018 Mar;126(3):207-214. doi: 10.1002/cncy.21958. Epub 2017 Dec 26.

Abstract

Background: In the current study, the authors evaluated the impact of implementing The Paris System for Reporting Urinary Cytology (PSRUC) on the prevalence of various cytological categories and their association with a subsequent diagnosis of high-grade urothelial carcinoma (HGUC).

Methods: A comparative study was conducted over the 6-month period before PSRUC implementation (2013), including 1653 patients and 2371 specimens versus a 6-month period after implementation of the PSRUC (2016), including 1478 patients and 2392 specimens. The following cytological categories were correlated with the subsequent biopsy result when available (355 cases): negative for HGUC (NHGUC), atypical urothelial cells (AUC), suspicious for HGUC, and HGUC.

Results: Although 18.6% of specimens were diagnosed as AUC in 2013, the percentage was 14.4% in 2016 (P < .0001). Concurrently, the prevalence of the "benign" category increased from 2013 to 2016 (75.4% vs 80%; P < .0001). After implementation of the PSRUC, there was no significant change noted with regard to the association between the categories of NHGUC, suspicious for HGUC, and HGUC and a subsequent HGUC biopsy diagnosis. However, the predictive value of an AUC diagnosis increased from 28.3% to 46.1% (P = .077). Most important, after the implementation of the PSRUC, there was a significant difference noted with regard to the predictive association for HGUC between the NHGUC and AUC groups (13.6% vs 46.1%; P = .003), a difference that was not found to be statistically significant before implementation of the PSRUC (18% vs 28.3%; P = .175).

Conclusions: There was a much higher risk of HGUC conveyed by AUC cytology after implementation of the PSRUC, justifying more aggressive investigations of patients who receive an AUC diagnosis. Cancer Cytopathol 2018;126:207-14. © 2017 American Cancer Society.

Keywords: Paris System for Reporting Urinary Cytology; atypical; correlation; cytology; performance; urine.

MeSH terms

  • Carcinoma, Transitional Cell / diagnosis*
  • Carcinoma, Transitional Cell / pathology*
  • Cytodiagnosis
  • Humans
  • Neoplasm Grading
  • Urinary Bladder Neoplasms / diagnosis*
  • Urinary Bladder Neoplasms / pathology*