With the advent of the Paris System for the Reporting of Urinary Cytology, there will be changes to everyday practice. As the studies of high- and low-grade urothelial neoplasms have revealed them to be different disease processes, the Paris System focuses on the detection of high-grade urothelial carcinoma, as it is the most clinically significant. The cytologic features, nuclear-to-cytoplasmic ratio, nuclear hyperchromasia, and nuclear irregularities, are the criteria for progressing the diagnosis to high-grade, and the finding of papillary clusters is the sole architectural criterion to make the diagnosis of low-grade urothelial neoplasm. Any finding that does not suggest an increased risk of a high-grade lesion is diagnosed as negative for high-grade urothelial carcinoma. The purpose of this article is to highlight some of the most important changes through the review of exemplary cases. For each case, there is a vignette, a description of the findings on urine cytology, and a discussion of the rationale for the final diagnostic category.
From the Medical University of South Carolina, Charleston.
Reprints: Kathryn G. Lindsey, MD, Medical University of South Carolina, 165 Ashley Avenue, Suite 309, MSC 908, Charleston, SC 29425. E-mail: email@example.com.
The authors have no funding or conflicts to declare.