Introduction: Discriminating between malignant and nonmalignant conditions remains a challenge in the evaluation of patients with asymptomatic microhematuria. In this prospective study the role of immunocytology in the assessment microhematuria was studied.
Material and methods: uCyt is a commercially available immunocytological assay based on microscopical detection of tumor-associated antigens in urothelial cells by immunofluorescence. Between September 2000 and December 2006, 222 consecutive patients with newly diagnosed painless microhematuria without prior transitional cell carcinoma were included. All urine samples were examined cytologically and immunocytologically. A total of 211 samples (95%) were assessable.
Results: Clinical examination by physical examination, cystoscopy, laboratory tests, and imaging yielded bladder cancer in ten cases (4%). Further diagnoses were BPH (27%), cystitis (including IC) (12%), urolithiasis (9%), urethral or ureteral strictures (6%), papilloma (2%), and"further conditions" (16%). In 52 patients (23%) reasons for hematuria were not identified. Immunocytology was positive in 8 of 10 bladder tumors (80%) and negative in 178 patients with non-tumor-related hematuria (89%).
Conclusions: The high sensitivity and good specificity of immunocytology is comparable with that reported in the literature despite a very low disease prevalence in this population. If assessment of these patients would have only been based on immunocytology, 180 costly and invasive diagnostic procedures would have been saved, with only 29 individuals (14%) undergoing these examinations unnecessarily. The authors conclude that these findings justify further investigation of this issue.