The Value Of UCyt Immunofluorescence And CK20 Immunoctyochemistry Detection As Diagnostic Adjuncts To Urine Liquid-based Cytology Examination

Objectives: To investigate the value of urine liquid-based cytology (LBC), uCyt immunofluorescence and CK20 ICC (cytokeratin 20 immunoctyochemistry, CK20 ICC) detection in the diagnoses of urothelial carcinoma (UC).Materials and methods: This study included two parts of prospective and retrospective investigations. In the prospective investigation, we randomly collected voided urine from inpatients in Cancer Hospital of Chinese Academy of Medical Science (CHCAMS), and voided urine from the health for healthy control. LBC, uCyt immunofluorescence and CK20 ICC tests were performed in these cases. In the retrospective study, we selected liquid-based slides with cytological diagnoses≥AUC (atypical urothelial cells) from the cytological department of CHCAMS, and performed CK20 ICCis (ICC in situ) detection on these slides. All the examinations were made without knowing each other. Finally, taking histology diagnoses as gold standard, the data was analyzed.Results: Totally, 232 had histology results, including 155 UC, 38 non-urothelial malignancy and 39 benign lesions. There were 133 cases and 22 healthy controls in the prospective investigation, and there were 99 cases in the retrospective investigation.1. Sensitivity of LBC, uCyt immunofluorescence and CK20 ICC detection was 48.3%, 81.8% and 76.2%, respectively; specificity was 98.3%, 91.4% and 96.7%, respectively, uCyt immunofluorescence and CK20 ICC detection had a good coincidence (Kappa Value=0.674).2. 42.9% UC had cytological diagnoses of SuCA( suspicious carcinoma) and AUC, and in these cases, the positive rates of uCyt immunofluorescence and CK20 ICC detection was 81.1% and 76.5%, respectively; but in the benign lesions with cytological diagnoses of SuCA and AUC, the positive rates of uCyt immunofluorescence and CK20 ICC detection was 40.0% and 0.0%, respectively. The rates in UC and benign lesions had significant difference(uCyt P=0.039, CK20 ICC P＜0.001).3. Sensitivity of LBC was 36.4%, 38.7% and 78.3% for UC G1,G1-2,G2,G2-3 and G3, that of uCyt immunofluorescence was found to be 75.8%, 83.3% and 87.0%. Whereas that of CK20 ICC detection were 65.6%, 75.0% and 90.9%, respectively. When LBC was combined with uCyt immunofluorescence, the sensitivity reached 75.8%(25/33), 80.6%(25/31) and 95.7%(22/23); when adding CK20 ICC detection to LBC examination, sensitivity reached 72.7%(24/33), 74.2%(23/31) and 91.3 %(21/23). Sensitivity reached 78.8 %(26/33), 90.3%(28/31) and 95.7%(22/23) when three of them were combined together.4. The positive rate of CK20 ICCis detection was 92.4%, higher than that in CK20 ICC detection, but the difference had no significance (P=0.133). In the UC with cytological diagnoses of SuCA and AUC, the positive rate of CK20 ICCis detection was 91.9%; but in the benign lesions with cytological diagnoses of SuCA and AUC, the positive rate was 4.8%, respectively. The two positive rates had significant difference (P＜0.001).5. In the non-urothelial malignancy cases, the positive rate of CK20 was 17.2% (5/29), and the positive rate of uCyt was 11.5% (3/26). Both of the rates were significantly lower than that in UC(P＜0.05).Conclusions: In the diagnoses of UC, uCyt immunofluorescence and CK20 ICC detection could assist LBC to differentiate SuCA and AUC, and improved the sensitivity of LBC, especially for low grade UC. uCyt immunofluorescence and CK20 ICC detection had a good coincidence. CK20 ICCis was a simple and effective method, and its positive rate to UC was higher than CK20 ICC.