Purpose: Both BTA TRAK and NMP22 urine concentrations have shown a sensitivity superior to urine cytology in the detection of bladder cancer. We compared these tumor markers with urine cytology performed on 3 consecutive samples and evaluated by an expert cytopathologist.
Patients and methods: The investigations were conducted on 94 patients undergoing a diagnostic cystoscopy for a high suspicion of bladder cancer (group 1) and on 102 patients with previous history of transitional cell carcinoma awaiting a follow-up cystoscopy (group 2). Biopsy specimens were obtained also from tumor negative patients. Immunoassays for BTA TRAK and NMP22 were carried out according to standard methods. The choice of the cut-off was based on the ground of sensitivity and specificity curves intersection. Urine cytology results were expressed as positive, negative and 'dubious'.
Results: Overall sensitivity was 56% for NMP22 (cut-off 11 U/ml) and 57% for BTA TRAK (cut-off 60 U/ml). When dubious results were considered as positive cases, urine cytology achieved a sensitivity of 73.3%. Assuming dubious cases as negative results, urine cytology sensitivity resulted 59.3%. When the 2 groups of patients were evaluated separately with different cut-off, there was no significant gain in sensitivity for BTA TRAK and NMP22 over urine cytology.
Conclusions: Urine cytology performed on 3 samples showed the highest sensitivity and specificity. The diagnostic advantage of urine cytology over BTA TRAK and NMP22 was maintained when patients were stratified by tumor grade.
Copyright 2000 S. Karger AG, Basel