Bladder wash cytology and flow cytometry for the diagnosis of transitional cell carcinoma of the urinary bladder.

: The role of bladder wash (BW) cytology and flow cytometry in the diagnosis of low-grade transitional cell carcinoma (TCC) of the bladder is yet to be demonstrated. We have studied a series of BW specimens by both conventional cytology and flow cytometry: there were 16 BW from patients with histologically proven TCC and 14 BW from patients with clinical suspicion of tumor or under follow-up for previous TCC in which no evidence of tumor was found by cystoscopy and multiple biopsies. As control group, 21 BW were studied from patients undergoing cystoscopy for causes other than TCC. In conclusion, the conventional cytologic study of BW specimens was highly sensitive for grade II-III TCC, but missed most grade I TCC; flow cytometric analysis did not improve significantly the detection rate in low-grade TCC.