ProEx C as an adjunct marker to improve cytological detection of urothelial carcinoma in urinary specimens
Article first published online: 30 JAN 2013
Copyright © 2013 American Cancer Society
Volume 121, Issue 6, pages 320–328, June 2013
How to Cite
Moatamed, N. A., Rao, J.-Y., Alexanian, S., Cobarrubias, M., Levin, M., Lu, D. and Apple, S. K. (2013), ProEx C as an adjunct marker to improve cytological detection of urothelial carcinoma in urinary specimens. Cancer Cytopathology, 121: 320–328. doi: 10.1002/cncy.21264
- Issue published online: 13 JUN 2013
- Article first published online: 30 JAN 2013
- Manuscript Accepted: 29 OCT 2012
- Manuscript Revised: 27 OCT 2012
- Manuscript Received: 1 SEP 2012
- urine cytology;
- ProEx C;
- urothelial atypia;
ProEx C is an antibody cocktail targeting the expression of topoisomerase IIα and minichromosome maintenance protein-2. ProEx C staining is being used to assist in diagnoses of the gynecological specimens. This study was designed to determine the utility of ProEx C in urine cytology samples for improving the detection of urothelial carcinomas where a significant number of urine cytology specimens are diagnosed as “atypia.”
Sixty urinary specimens (12 negative, 13 positive, and 35 atypical cases) were stained with ProEx C, and ProEx C results were recorded as positive when nuclear staining was only seen in at least one morphologically atypical urothelial cell.
All 12 benign cytology samples showed negative staining with ProEx C. Twelve of 13 cases that had a malignant cytologic diagnosis showed a positive nuclear staining of the malignant cells. Eighteen of 35 cases with atypical cytologic diagnoses showed positive nuclear staining. Of the 35 cases with “atypia,” 17 had a malignant histopathologic follow-up. In this study, ProEx C stain had an overall sensitivity of 78.4%, specificity of 95.7%%, positive predictive value of 96.7%, and negative predictive value of 73.3% for the detection of urothelial carcinoma.
ProEx C stain is a useful adjunct test to urine cytologic analysis, even in specimens with limited cellularity. In urinary smears, this test is most useful in stratification of the “atypical” diagnoses into benign and malignant subsets. To the authors' knowledge, this is the first study of ProEx C application in urine cytology as an adjunct marker for detection of urothelial carcinoma. Cancer (Cancer Cytopathol) 2013;121:320–8. © 2013 American Cancer Society.