Dual-parameter immunoflow cytometry in diagnosis and follow-up of patients with bladder cancer

Objectives: The aim of this study was to evaluate the clinical significance of a dual-parameter immunoflow cytometry (DPI-FCM) assay in the detection of tumor cells in barbotage specimens of bladder cancer patients. Methods: DPI-FCM is an automated method, based on the utilization of two monoclonal antibodies (mAbs) either used for a preselection of urothelial cells (mAb Due AUT 2) or the analysis of the expression of a differentiation antigen within the preselected urothelial cells (mAb Due ABC 3), The ratio of ABC 3-positive urothelial cells was used to discriminate between the normal and malignant state of the urothelium. At the time of examination 40 patients had endoscopically overt bladder tumors. Another 30 patients without endoscopically visible tumors were examined before routine rebiopsy, Thirty barbotage specimens from patients with diseases not related to bladder cancer were examined as controls. Results: Overall, the sensitivity of DPI-FCM in patients with endoscopically overt and invisible residual tumors was 95 and 83%, respectively, regardless of concomitant urinary tract infection. The sensitivity of DPI-FCM for both patient groups was 86, 95 and 94% for tumor grades 1, 2 and 3, respectively. The specificity of the method in 30 patients with no history of bladder cancer was 93%, Conclusions: DPI-FCM appears to be a highly reliable method of recognizing tumor cells in bladder barbotage specimens even in patients with concomitant urinary tract infection. The procedure may be of value in monitoring bladder cancer patients for tumor recurrence.