A Key Feature of Atypical Cells in Urinary Sediment for Urothelial Carcinoma Screening

Abstract

Objective: This study aimed to determine the potential of atypical cell nuclei identified by urinary sediment testing for urothelial carcinoma screening.

Methods: The study subjects consisted of 38 health checkup examinees in whom atypical cell nuclei had been found by urinary sediment testing during health checkups. Urologists assessed the presence or absence of urothelial carcinoma. The types of atypical cell nuclei were defined according to “Examination of Urinary Sediment 2010”, a document approved by the Japanese Committee for Clinical Laboratory Standards, as follows: enlarged nuclei, increased chromatin amount, irregular nuclear shape, and enlarged nucleoli. The relationship between these four types of atypical cell nuclei and urothelial carcinoma was determined in a retrospective cross-sectional study.

Results: Among the four types of atypical cell nuclei, irregular nuclear shape had the highest accuracy with a sensitivity of 0.826, a specificity of 0.933, and a likelihood ratio of 12.391. The rates of atypical cell nuclei found in subjects with (n=23) and without (n=15) urothelial carcinoma were as follows: enlarged nuclei, 91% vs. 80%; increased chromatin amount, 100% vs. 93%; irregular nuclear shape, 83% vs. 7%; and enlarged nucleoli, 35% vs. 20%. The irregular nuclear shape had the highest positive predictive value (95%). Multiple logistic regression analysis showed that irregular nuclear shape (odds ratio, 85.30; 95% confidence interval, 7.2–1010.0) was related to urothelial carcinoma (p<0.001).

Conclusion: Urinary sediment testing during health checkups is likely to be useful for urothelial carcinoma screening.