MONOCLONAL-ANTIBODY DUE ABC-3 DIRECTED AGAINST TRANSITIONAL CELL-CARCINOMA .3. PROSPECTIVE TRIAL ON THE DIAGNOSTIC-VALUE OF IMMUNOCYTOLOGY USING MONOCLONAL-ANTIBODY DUE ABC-3

Recently, the development of monoclonal antibody Due ABC 3 directed against transitional cell carcinoma has been reported. With this monoclonal antibody an in vitro test system for diagnosis and followup of patients with transitional cell carcinoma has been developed. The clinical value of this assay, designated as quantitative immunocytology, was evaluated in a prospective trial and compared to conventional cytology. We investigated 74 voided urine specimens obtained from patients with histologically proved transitional cell carcinoma and 60 specimens from donors without clinical evidence of transitional cell carcinoma. Sensitivity was 66% versus 47% for immunocytology and conventional cytology. Specificity of conventional cytology (92%) was higher compared to immunocytology (58%). Statistical analysis demonstrated a significantly higher sensitivity of the combined analysis of conventional cytology and immunocytology (p < 0.001) compared to conventional cytology alone, without significant differences in specificity. The results obtained with immunocytology were impaired by the great number of nonevaluable specimens. Poor preservation of cells, severe pyuria or an insufficient number of urothelial cells prevented evaluation in 25% of the cases, while only 6% could not be evaluated by conventional cytology. The ability of immunocytology to improve the sensitivity of conventional cytology makes this technique a promising adjunct to the noninvasive diagnosis of transitional cell carcinoma.