Immunocytology in the assessment of patients with asymptomatic hematuria

Painless hematuria has remained a diagnostic challenge in daily urological practice. Key problem in the assessment of these patients is the discrimination between malignant and non-malignant conditions. In this prospective study the role of immunocytology in the evaluation of patients with hematuria was investigated. Ucyt is a commercially available immunocytological assay based upon microscopical detection of tumor-associated antigens on the membrane of urothelial cells by immunofluorescence. Between October 2000 and July 2007, 301 consecutive patients with a first episode of painless hematuria without prior transitional cell carcinoma were included. Urine samples were obtained from all patients and examined cytologically and immunocytologically. Clinical assessment by physical examination, laboratory tests, endoscopy and imaging in 228 cases with microhematuria and 66 cases with gross hematuria yielded bladder cancer in 10 (4.6%) and 17 (27%) patients, respectively. Clinical workup demonstrated that composition of both groups was entirely different. Sensitivity of cystoscopy and immunocytology was similar in both groups. Furthermore, a negative finding in cystoscopy and immunocytology virtually excluded the presence of urothelial cancer. However, while predictive values of immunocytology were clearly superior to cytology in gross hematuria, cytology performed better in the microhematuria cohort. Combination of cystoscopy and immunocytology yield 100% sensitivity in the assessment of patients with painless hematuria. Based upon performance characteristics the authors recommend to replace urine cytology by a more sensitive marker like immunocytology in gross hematuria. In patients with microhematuria immunocytology could be used to select for patients at risk for urothelial cancer and thus spare negative patients from further examinations.