Abstract
Objective : The URO17® Bladder Cancer Kit (URO17 test) is a new immunocytochemistry-based test used to detect keratin 17 (K17)-positive urothelial carcinoma (UC) cells in urinary cytology specimens. We used the URO17 test to evaluate auto-smear urine specimens.
Study Design : A total of 176 patients who underwent urinary cytology examination and received clinicopathological diagnoses within one year were enrolled in this study. Auto-smear specimens were stained using the URO17® antibody (mouse anti-human K17). Detection of more than 20 strongly stained cells was considered as representing a positive result in the URO17 test.
Results : Clinicopathologically, 101 cases were diagnosed as having malignancy, of which 98 were cases of UC. The sensitivity and specificity of urinary cytology for detecting UC were 63.3％ and 82.1％, and those of the URO17 test were 83.3％ and 76.9％, respectively. Presence of only a few UC cells and/or low expression of K17 in some cases of UC, or high expression of K17 in some non-neoplastic urothelial cells influenced the accuracy of the URO17 test. In regard to low-grade UC, the URO17 test was positive in 14 of the 18 patients (77.8％), whereas urinary cytology indicated malignancy or suspicion of malignancy in only 6 of the 18 patients (33.3％).
Conclusions : The same samples were used for the URO17 test, a simple immunocytochemical assay for keratin 17, as for the urinary cytology. However, higher-quality urine specimens (e.g., liquid-based cytology specimens) may improve the accuracy of the URO17 test.
